{"PMID":31512372,"Year":2019,"Title":"MicroRNAs expression profiling in Egyptian colorectal cancer patients.","Abstract":"Egypt has increased incidence and high rate of early onset colorectal cancer (CRC). This study aimed to profile the expression levels of 84 circulating microRNAs (miRNAs) in Egyptian CRC patients and to evaluate the diagnostic accuracy of some selected miRNAs as diagnostic biomarkers for CRC patients. A total of 129 subjects (84 CRC patients and 45 healthy controls) were enrolled in two independent sample sets: the screening set (39 subjects) and the validation set (90 subjects). The expression profiles of 84 miRNAs were studied by miRNA PCR array in the screening set. Then four miRNAs (let-7c, 21, 26a, 146a) were selected to be studied by quantitative real-time PCR in the validation set. The PCR array results revealed significant up regulation of 20 miRNAs and downregulation of two miRNAs in CRC patients compared to the healthy subjects. Moreover, the expression levels of the four selected miRNAs were significantly higher in CRC serum samples than controls. The ROC analysis revealed that miRNAs (let-7c, 21, 26a and 146a) can effectively discriminate between CRC patients and the controls. The combination of the four miRNAs showed AUC of 0.950 (95% CI [0.898-1.002], p = .001). However, the combination of miR-21 and miR-26a showed the best diagnostic accuracy with AUC of 0.953 (95% CI [0.908-0.999], p = .001). The current data suggest that miRNAs (let-7c, 21, 26a, 146a) could play an important role in CRC development and they can be used as diagnostic biomarkers for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31505885,"Year":2019,"Title":"In Vitro and In Silico Mechanistic Insights into miR-21-5p-Mediated Topoisomerase Drug Resistance in Human Colorectal Cancer Cells.","Abstract":"Although chemotherapy for treating colorectal cancer has had some success, drug resistance and metastasis remain the major causes of death for colorectal cancer patients. MicroRNA-21-5p (hereafter denoted as miR-21) is one of the most abundant miRNAs in human colorectal cancer. A Kaplan-Meier survival analysis found a negative prognostic correlation of miR-21 and metastasis-free survival in colorectal cancer patients (The Cancer Genome Atlas Colon Adenocarcinoma/TCGA-COAD cohort). To explore the role of miR-21 overexpression in drug resistance, a stable miR-21-overexpressing clone in a human DLD-1 colorectal cancer cell line was established. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay found that miR-21 overexpression induced drug resistance to topoisomerase inhibitors (SN-38, doxorubicin, and etoposide/VP-16). Mechanistically, we showed that miR-21 overexpression reduced VP-16-induced apoptosis and concomitantly enhanced pro-survival autophagic flux without the alteration of topoisomerase expression and activity. Bioinformatics analyses suggested that miR-21 overexpression induced genetic reprogramming that mimicked the gene signature of topoisomerase inhibitors and downregulated genes related to the proteasome pathway. Taken together, our results provide a novel insight into the role of miR-21 in the development of drug resistance in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31482406,"Year":2019,"Title":"Assessment of Serum MicroRNA-21 Gene Expression for Diagnosis and Prognosis of Colorectal Cancer.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are small, non-coding RNAs that are involved in carcinogenesis through posttranscriptional gene regulatory activity. The current study aimed to evaluate serum miR-21 expression levels as potential biomarkers for diagnosis and prognosis of colorectal cancer (CRC) patients. METHODS: Quantitative real-time RT-PCR was applied to determine the relative expression level of miR-21 in serum. At the same time, the sensitivity and specificity of this marker were evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: miR-21 expression levels of serum were 3.4 and 1.25 in patient and control, respectively (p < 0.05). The sensitivity and specificity of miR-21 were found to be 95.8% and 91.7%, respectively. The high expression level of serum miR-21 were associated with higher local recurrence, TNM staging, PT staging, venous invasion, liver metastasis, and recurrence (p < 0.05). CONCLUSION: The results of this study indicated that miR-21 expression levels in serum can be considered as a novel non-invasive biomarker for early detection and prognosis of CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31469874,"Year":2019,"Title":"MicroRNA regulation in colorectal cancer tissue and serum.","Abstract":"Colorectal cancer is recognized as the fourth leading cause of cancer-related deaths worldwide. Thus, there is ongoing search for potential new biomarkers allowing quicker and less invasive detection of the disease and prediction of the treatment outcome. Therefore, the aim of our study was to identify colorectal cancer specific miRNAs expressed in cancerous and healthy tissue from the same patient and to further correlate the presence of the same miRNAs in the circulation as potential biomarkers for diagnosis. In the current study we detected a set of 40 miRNAs differentially regulated in tumor tissue when comparing with healthy tissue. Additionally, we found 8 miRNAs differentially regulated in serum of colorectal cancer patients. Interestingly, there was no overlap in miRNAs regulated in tissue and serum, suggesting that serum regulated miRNAs may be not actively secreted from colorectal tumor cells. However, four of differentially expressed miRNAs, including miR-21, miR-17, miR-20a and miR-32 represent the miRNAs characteristic for different tumor types, including breast, colon, lung, pancreas, prostate and stomach cancer. This finding suggests important groups of miRNAs which can be further validated as markers for diagnosis of tumor tissue and regulation of carcinogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31359311,"Year":2019,"Title":"MicroRNAs play an important role in contributing to arsenic susceptibility in the chronically exposed individuals of West Bengal, India.","Abstract":"Arsenic exposure by groundwater contamination is a menace which threatens more than 26 million individuals of West Bengal. Interestingly, with similar levels of arsenic exposure, only 15-20% of the population show arsenic-induced skin lesions, the hallmarks of chronic arsenic toxicity, but the rest do not. In this study, our aim was to identify whether microRNAs (miRNA) have any role to play in causing such arsenic susceptibility. Global plasma miRNA profiling was done in 12 arsenic-exposed individuals with skin lesions and 12 exposed individuals without skin lesions. Two hundred two miRNAs were found to be differentially regulated between the two study groups. Results were validated by quantitative real-time PCR in 30 exposed subjects from each of the groups, which showed that among others miR-21, miR-23a, miR-27a, miR-122, miR-124, miR-126, miR-619, and miR-3613 were significantly upregulated and miR-1282 and miR-4530 were downregulated in the skin lesion group compared with the no skin lesion group. Bioinformatic analyses predicted that these altered miRNAs have targets in 7 different biochemical pathways, including glycerophospholipid metabolism, colorectal cancer, glycosphingolipid biosynthesis, T cell receptor signaling, and neurotrophin signaling pathways; glycerophospholipid metabolism pathway being the most enriched pathway. Association study show that these microRNAs contribute significantly to the increased prevalence of other non-dermatological health effects like conjunctival irritations of the eyes and respiratory distress in the study subjects. To our knowledge, this is the first study of its kind involving miRNA expressions contributing to arsenic susceptibility in the exposed population of West Bengal.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31263200,"Year":2019,"Title":"Faecal microRNAs as a non-invasive tool in the diagnosis of colonic adenomas and colorectal cancer: A meta-analysis.","Abstract":"MicroRNAs (miRNAs) are proposed as potential biomarkers for the diagnosis of numerous diseases. Here, we performed a meta-analysis to evaluate the utility of faecal miRNAs as a non-invasive tool in colorectal cancer (CRC) screening. A systematic literature search, according to predetermined criteria, in five databases identified 17 research articles including 6475, 783 and 5569 faecal-based miRNA tests in CRC, adenoma patients and healthy individuals, respectively. Sensitivity, specificity, positive/negative likelihood and diagnostic odds ratios, area under curve (AUC), summary receiver operator characteristic (sROC) curves, association of individual or combinations of miRNAs to cancer stage and location, subgroup, meta-regression and Deeks' funnel plot asymmetry analyses were employed. Pooled miRNAs for CRC had an AUC of 0.811, with a sensitivity of 58.8% (95% confidence interval [CI]: 51.7-65.5%) and specificity of 84.8% (95% CI: 81.1-87.8%), whilst for colonic adenoma, it was 0.747, 57.3% (95% CI: 40.8-72.3%) and 76.1% (95% CI: 66.1-89.4%), respectively. The most reliable individual miRNA was miR-21, with an AUC of 0.843, sensitivity of 59.3% (95% CI: 26.3-85.6%) and specificity of 85.6% (95% CI: 72.2-93.2%). Paired stage analysis showed a better diagnostic accuracy in late stage CRC and sensitivity higher in distal than proximal CRC. In conclusion, faecal miR-21, miR-92a and their combination are promising non-invasive biomarkers for faecal-based CRC screening.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31234350,"Year":2019,"Title":"Plasma microRNA Levels Combined with CEA and CA19-9 in the Follow-Up of Colorectal Cancer Patients.","Abstract":"Colorectal cancer (CRC) ranks among the most common cancers worldwide. Surgical removal remains the best strategy for treatment of resectable tumors. An important part of caring for patients after surgery is monitoring for early detection of a possible relapse of the disease. Efforts are being made to improve the sensitivity and specificity of routinely used carcinoembryonic antigen (CEA) with the use of additional biomarkers such as microRNAs. The aim of our study was to evaluate the prognostic potential of microRNAs and their use as markers of disease recurrence. The quantitative estimation of CEA, CA19-9, and 22 selected microRNAs (TaqMan Advanced miRNA Assays) was performed in 85 paired (preoperative and postoperative) blood plasma samples of CRC patients and in samples taken during the follow-up period. We have revealed a statistically significant decrease in plasma levels for miR-20a, miR-23a, miR-210, and miR-223a (p = 0.0093, p = 0.0013, p = 0.0392, and p = 0.0214, respectively) after surgical removal of the tumor tissue. A statistically significant relation to prognosis (overall survival; OS) was recorded for preoperative plasma levels of miR-20a, miR-21, and miR-23a (p = 0.0236, p = 0.0316, and p =0.0271, respectively) in a subgroup of patients who underwent palliative surgery. The best discrimination between patients with favorable and unfavorable outcomes was achieved by a combination of CEA, CA19-9 with miR-21, miR-20a, and miR-23a (p < 0.0001). The use of these microRNAs for early disease recurrence detection was affected by a low specificity in comparison with CEA and CA19-9. CEA and CA19-9 had high specificity but low sensitivity. Our results show the benefit of combining currently used standard biomarkers and microRNAs for precise prognosis estimation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31216561,"Year":2019,"Title":"Stool-Based miR-92a and miR-144* as Noninvasive Biomarkers for Colorectal Cancer Screening.","Abstract":"OBJECTIVES: Current noninvasive screening tests for colorectal cancer (CRC) have insufficient sensitivity. MicroRNA (miRNA) levels in stool have potential as markers for noninvasive screening of CRC. We evaluated the diagnostic value of stool miRNA levels and determined the optimal miRNA subtypes for detecting CRC. METHODS: Stool samples were collected from 29 patients with CRC and 29 healthy controls. The stool levels of miR-21, miR-92a, miR-200c, miR-144*, miR-135a, miR-135b, miR-106a, and miR-17-3p were determined by real-time quantitative reverse transcription polymerase chain reaction. The sensitivity and specificity of the miRNAs for CRC were determined by receiver operating characteristics analysis. RESULTS: Among the eight tested miRNAs, the mean stool levels of miR-21, miR-92a, miR-144*, and miR-17-3p differed significantly between the CRC group and the control group (p =0.014, 0.001, <0.001, and 0.008, respectively). The sensitivities and specificities of miR-21, miR-92, miR-144*, and miR-17-3p were 79.3 and 48.3%, 89.7 and 51.7%, 78.6 and 66.7%, and 67.9 and 70.8%, respectively. In a multivariate analysis, miR-92a and miR-144* were significantly associated with the presence of CRC (p = 0.03 and 0.011, respectively). CONCLUSIONS: The stool levels of miR-92a and miR-144* showed good sensitivity and fair specificity for detection of CRC, and thus may be useful as noninvasive biomarkers for this disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31115212,"Year":2019,"Title":"Combined Plasma MicroRNA and Fecal Occult Blood Tests in Early Detection of Colorectal Cancer.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies and a major cause of cancer-related death worldwide. Fecal occult blood tests (FOBT) are non-invasive colorectal cancer screening tests. In recent years plasma microRNAs (miRNAs) have shown great potential in early non-invasive cancer detection. METHODS: FOBT (immunochemical) and a panel of 12 plasma miRNAs were tested in two independent groups: 57 CRC patients and 125 neoplasm free controls, in addition to 58 advanced adenoma patients and 67 neoplasm free controls. miRNA levels were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Plasma levels of 7 miRNAs (miR-18a, miR-20a, miR-21, miR-92a, miR-133a, miR-143, miR-145) differed significantly between CRC patients and neoplasm free controls. miRNA plasma levels did not differ between advanced adenoma patients and controls. For 7 dysregulated miRNAs in CRC patients, AUCs ranged from 0.585 to 0.632 for CRC detection, in comparison to an AUC of 0.857 for iFOBT. The combination of miR-133a and iFOBT achieved a higher AUC (0.894) than iFOBT alone. At 97.8% specificity, miRNAs showed much lower sensitivities than iFOBT, but the miRNA panel and iFOBT in combination detected CRC with a higher sensitivity than iFOBT alone. CONCLUSIONS: The diagnostic performance of miRNAs was poorer than iFOBT. Nevertheless, plasma miRNA profiles offer an innovative non-invasive approach for early CRC detection. The potential advantage of combining plasma miRNA profiles with iFOBT needs to be further studied in a larger cohort of patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31102171,"Year":2019,"Title":"MicroRNA Expression and Correlation with mRNA Levels of Colorectal Cancer-Related Genes.","Abstract":"INTRODUCTION: MicroRNAs (miRNAs), as a family of non-coding RNAs, have opened a new window in cancer biology and transcriptome. It has been revealed that miRNAs post-transcriptionally regulate the gene expression and involve in colorectal cancer (CRC) development and progression. Our aim was to examine the differential expression of miRNAs in a CRC and to correlate their expression levels with mRNA levels of CRC-related genes (K-ras, APC, p53). MATERIALS AND METHODS: Seventy-two colorectal tumor tissues from patients with newly diagnosed CRC and 72 matched normal adjacent tissues were analyzed. Relative expression of seven CRC-related miRNAs (miR-21, miR-31, miR-20a, miR-133b, and miR-145, miR-135b and let-7g) and three CRC-related genes (K-ras, APC, p53) was detected using the SYBR Green quantitative real-time PCR technique. The correlation between gene expression levels and clinicopathological features was evaluated. RESULTS: Our results showed a significant difference between the two groups for the expression level of miR-21, miR-31, miR-145, and miR-20a (P < 0.001). Also, a significant difference between the two groups for the expression level of K-ras was found (P < 0.001). Further analysis revealed an inverse significant correlation between miR-145 and K-ras (R(2) = 0.662, P < 0.001), while a positive correlation was observed between miR-21 and K-ras (R(2) = 0.732, P < 0.001). CONCLUSION: Dysregulation of miRNAs and correlation with molecular signaling pathways designated a biological role for miRNAs in various cellular mechanisms underlying CRC. On the other hand, the pattern of miRNAs expression and its correlation with transcriptional status are helpful to discovery biomarkers and design therapeutics for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31095784,"Year":2019,"Title":"The diagnostic efficacy of circulating miRNAs in monitoring the early development of colitis-induced colorectal cancer.","Abstract":"Early detection of colorectal cancer and monitoring the progress in colon carcinogenesis stages is essential to reduce mortality. Therefore, there is continuous search for noninvasive biomarkers with high stability and good sensitivity and specificity. miRNAs have attracted attention as promising biomarkers as they are stably expressed in circulation. The aim of our study is to evaluate the aberrant expression of circulating miRNAs during the stepwise progress of colitis-associated colon cancer. This was accomplished through assessing the expression levels of five miRNAs (miR-141, miR-15b, miR-17-3p, miR-21, and miR-29a) in serum and their corresponding tissue samples through the different cycles of colorectal carcinogenesis cascade using the azoxymethane/dextran sulfate sodium murine model. We also compared the diagnostic performance of these selected miRNAs with the conventional tumor biomarkers CEA and CA 19-9. The results of our study revealed that the expression levels of those miRNAs were dynamically changing in accordance with the tumor development state. Moreover, their aberrant expression in serum was statistically correlated with that in tissue. Our data also revealed that serum miR-15b, miR-21, and miR-29a showed the best performance in terms of diagnostic power. Our findings highlight the efficiency of these circulating miRNAs not only for early diagnostics purposes, but also for monitoring progress in the colorectal carcinogenesis process, and therefore encouraging integrating these noninvasive biomarkers into the clinical diagnostic settings beside the traditional diagnostic markers for accurate screening of the early progress of colon carcinogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31089750,"Year":2019,"Title":"A panel of serum exosomal microRNAs as predictive markers for chemoresistance in advanced colorectal cancer.","Abstract":"BACKGROUND: Chemoresistance is a common problem for cancer treatment worldwide. Circulating exosomal microRNAs (miRNAs) have been considered as promising biomarkers of cancers. However, few studies have assessed the relationship between serum/plasma exosomal microRNAs and chemoresistance in colorectal cancer (CRC). METHODS: Based on previous microarray analysis, we selected 30 miRNAs which are aberrantly expressed during CRC progression and then detected their expression levels in three pairs of oxaliplatin/5-fluorouracil-resistant CRC cell lines and the corresponding secreted exosomes. Six candidate exosomal miRNAs were identified for further evaluating potential value in predicting chemotherapeutic effect in advanced CRC patients. Finally, the molecular mechanisms of these miRNAs in drug resistance were explored by bioinformatics preliminarily. RESULTS: We observed that the expression of 14 miRNAs was significantly higher in three drug-resistant CRC cells comparing with their parental cells. Among these miRNAs, miR-21-5p, miR-1246, miR-1229-5p, miR-135b, miR-425 and miR-96-5p are also up-regulated in exosomes from culture media of resistant cells. Clinical sample analysis confirmed that the expression levels of miR-21-5p, miR-1246, miR-1229-5p and miR-96-5p in serum exosomes were significantly higher in chemoresistant patients in contrast with chemosensitive controls. ROC curve showed that the combination of the four miRNAs had an area of under the curve (AUC) of 0.804 (P < 0.05). In addition, GO analysis and KEGG pathway analysis revealed that these miRNAs were enriched in PI3K-Akt signaling pathway, FoxO signaling pathway and autophagy pathway. CONCLUSIONS: Our study demonstrates that a panel of serum exosomal miRNAs containing miR-21-5p, miR-1246, miR-1229-5p and miR-96-5p could significantly distinguish the chemotherapy-resistant group from advanced colorectal cancer patients. Targeting these miRNAs may promote chemosensitivity to oxaliplatin and 5-fluorouracil, and might be promising strategy for CRC treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31064190,"Year":2019,"Title":"Dynamic Changes in Circulating MicroRNA Levels in Liver Cancer Patients Undergoing Thermal Ablation and Transarterial Chemoembolization.","Abstract":"BACKGROUND: Hepatic cancer patients who cannot undergo surgical resection of tumour are candidates for methods of interventional radiology - transarterial chemoembolization (TACE) or thermal ablative (TA) therapy. Both methods are causing characteristic changes in liver tissue (inflammatory immune response, hypoxia, elevated temperature, tissue destruction) which are accompanied with systemic secretion of cytokines or microRNAs (miRNAs). The aim of our study was to investigate whether the level of circulating miRNAs related to hypoxia (miR-21 and miR-210), liver injury (miR-122) and epithelial-mesenchymal transition (miR-200a) could reflect systemic effect of these intervention techniques. MATERIALS AND METHODS: Study consisted of 10 primary hepatocellular carcinoma patients treated with TACE and 10 patients with liver metastases of colorectal cancer treated with TA. Thermal ablation was performed using the radiofrequency or microwave generator (RITA, Microsulis, AngioDynamics,Inc), for TACE drug eluting beads (DCBeads, Biocompatibles Ltd.) were used. Tumours were evaluated using RECIST (Response Evaluation Criteria in Solid Tumours), mRECIST (modified RECIST) criterion and volumetry. For all patients we determined concentrations of miRNA in blood plasma samples from four time points (before intervention, immediately after intervention, 24 hours after intervention, 1 week after intervention) using TaqMan(R) Assays and quantitative real time polymerase chain reaction method. RESULTS: After both intervention techniques we observed changes in circulating miRNA levels. In TA cases we observed significant increase of miR-122 and miR-200a concentrations immediately after intervention, on the contrary in TACE we observed increase in miRNA concentration at time point 24 hours after intervention (miR-21, miR-210, miR-122, miR-200a). Increased concentration of circulating miRNA was followed by subsequent decline to initial level. These changes were consistent with presumed biological effect of TA and TACE on tumour tissue. CONCLUSION: Data of this pilot study show potential usage of circulating miRNA for monitoring of systemic effect of thermal ablative and intraarterial therapies. This work was created at Masaryk University as part of the project MUNI/A/1574/2018 and it was supported by Czech Ministry of Health grants No. 15-32484A, 16-31765A and 16-31314A. The authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 1. 3. 2019 Accepted: 4. 3. 2019.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":31046485,"Year":2019,"Title":"Circulating cell-free nucleic acids as biomarkers in colorectal cancer screening and diagnosis - an update.","Abstract":"Introduction: Screening methods for one of the most frequently diagnosed malignancy, colorectal cancer (CRC), have limitations. Circulating cell-free nucleic acids (cfNA) hold clinical relevance as screening, prognostic and therapy monitoring markers. Area covered: In this review, we summarize potential CRC-specific cfNA biomarkers, the recently developed sample preparation techniques, their applications, and pitfalls. Expert opinion: Automated extraction of cfDNA is highly reproducible, however, cfDNA yield is less compared to manual isolation. Quantitative and highly sensitive detection techniques (e.g. digital PCR, NGS) can be applied to analyze genetic and epigenetic changes. Detection of DNA mutations or methylation in cfDNA and related altered levels of mRNA, miRNA, and lncRNA may improve early cancer recognition, based on specific, CRC-related patterns. Detection of cfDNA mutations (e.g. TP53, KRAS, APC) has limited diagnostic sensitivity (40-60%), however, methylated DNA including SEPT9, SFRP1, SDC2 can be applied with higher sensitivity (up to 90%) for CRC. Circulating miRNAs (e.g. miR-21, miR-92, miR-141) provide comparably high sensitivity for CRC as the circulating tumor cell mRNA markers (e.g. EGFR, CK19, CK20, CEA). Automation of cfNA isolation coupled with quantitative analysis of CRC-related, highly sensitive biomarkers may enhance CRC screening and early detection in the future.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30999696,"Year":2019,"Title":"Co-Detection of miR-21 and TNF-alpha mRNA in Budding Cancer Cells in Colorectal Cancer.","Abstract":"MicroRNA-21 (miR-21) is upregulated in many cancers including colon cancers and is a prognostic indicator of recurrence and poor prognosis. In colon cancers, miR-21 is highly expressed in stromal fibroblastic cells and more weakly in a subset of cancer cells, particularly budding cancer cells. Exploration of the expression of inflammatory markers in colon cancers revealed tumor necrosis factor alpha (TNF-alpha) mRNA expression at the invasive front of colon cancers. Surprisingly, a majority of the TNF-alpha mRNA expressing cells were found to be cancer cells and not inflammatory cells. Because miR-21 is positively involved in cell survival and TNF-alpha promotes necrosis, we found it interesting to analyze the presence of miR-21 in areas of TNF-alpha mRNA expression at the invasive front of colon cancers. For this purpose, we developed an automated procedure for the co-staining of miR-21, TNF-alpha mRNA and the cancer cell marker cytokeratin based on analysis of frozen colon cancer tissue samples (n = 4) with evident cancer cell budding. In all four cases, TNF-alpha mRNA was seen in a small subset of cancer cells at the invasive front. Evaluation of miR-21 and TNF-alpha mRNA expression was performed on digital slides obtained by confocal slide scanning microscopy. Both co-expression and lack of co-expression with miR-21 in the budding cancer cells was noted, suggesting non-correlated expression. miR-21 was more often seen in cancer cells than TNF-alpha mRNA. In conclusion, we report that miR-21 is not linked to expression of the pro-inflammatory cytokine TNF-alpha mRNA, but that miR-21 and TNF-alpha both take part in the cancer expansion at the invasive front of colon cancers. We hypothesize that miR-21 may protect both fibroblasts and cancer cells from cell death directed by TNF-alpha paracrine and autocrine activity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30880765,"Year":2019,"Title":"Evaluation of circulating miR-21 and miR-222 as diagnostic biomarkers for gastric cancer.","Abstract":"Introduction: Gastric cancer is responsible for a large number of death worldwide and its high death rate is associated with a lack of noninvasive tools in GC diagnosis. MicroRNAs (miRNAs), as gene regulators, were shown to dysregulate in different types of cancer. Moreover, it is proven that miRNAs are stable in serum/plasma, so they can be used as a potential noninvasive marker in GC diagnosis. The objective of this study is to investigate the plasma miRNA expression in GC samples compared to controls as a potential biomarker in cancer diagnosis. Materials and Methods: Expression levels of miR-21 and miR-222 were assessed using quantitative real-time polymerase chain reaction in plasma of 30 GC patients and 30 healthy controls. Diagnostic value of selected miRNAs was evaluated using receiver operating characteristic curve. Target prediction was done using bioinformatics tools to investigate the signaling pathways and function of the selected miRNAs. Results: Our results demonstrated that the expression levels of miR-21 and miR-222 were significantly higher in GC plasma than in the controls (P < 0.0001, P = 0.043). The sensitivity and specificity for miR-21 and in plasma were 86.7% and 72.2% and for miR-222 were 62.5% and 56.2%, respectively. Bioinformatics analysis revealed that most target genes of miR-21 and miR-222 are involved in cancer-related signaling pathway such as tumor initiation and progression. Conclusion: Our results indicated that miR-21 and miR-222 in plasma samples can be served as a potential noninvasive tool in GC detection. Furthermore, the miRNA target prediction manifested that miR-21 and miR-222 involve in key processes associated with GC initiation and development.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30862187,"Year":2019,"Title":"Bifidobacterium longum Suppresses Murine Colorectal Cancer through the Modulation of oncomiRs and Tumor Suppressor miRNAs.","Abstract":"The modulatory role of the Bifidobacterium longum (BL), isolated from women breast milk, on some oncogenic and tumor suppressor miRNAs as well as IL-1beta and IL6 targeted-miRNAs was investigated using murine colorectal cancer (CRC) induced on the top of inflammatory ulcerative colitis model. The investigation of the oncomiRs miR-21a and miR-155, which regulate IL-6 and IL-1beta expression, indicated that both was depressed by BL-administration in healthy and in CRC-mice. BL-administration induced the tumor suppressor miRNAs (miR-145 and miR-15a) expression in both of the healthy and in CRC-mice. The miR-146a expression, which regulates both of IL-1beta and IL-6 expression, was decreased after the BL-administration in both of the healthy and in CRC-mice. In CRC-mice, NF-Kb concentration was elevated, however this NF-Kb induction was diminished after the treatment with BL. BL highly enhanced the IL-1beta and IL-6 mRNA and protein concentrations in healthy mice. The administration of BL to CRC-mice resulted in a dramatic increase in IL-1beta mRNA and IL-1beta concentration, which in contrast was accompanied with a decrease in the IL-6 mRNA and IL-6 concentration. BL-administration resulted in a drop in the aberrant crypt foci number in CRC-mice and increased necrosis and fibrosis of the colon cells. The modulatory influence of B. longum on microRNAs may provide an important therapeutic impact in CRC through inhibition of the proliferation, invasion, apoptosis, and cell cycle of tumor cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30811964,"Year":2019,"Title":"Curcumol inhibits colorectal cancer proliferation by targeting miR-21 and modulated PTEN/PI3K/Akt pathways.","Abstract":"AIMS: The purpose of this study was to demonstrate how curcumol affected the expression of miR-21 and whether its effects on miR-21 was associated with the activation of PTEN/PI3K/Akt pathways in CRC cells. MAIN METHODS: MTT and xenograft assay were used to examine how curcumol inhibits colorectal cancer (CRC) cells' growth. Q-PCR and western blot analysis were employed to test the role of miR-21 in the inhibition of curcumol on proliferation and PTEN/PI3K/Akt pathways of CRC cells. KEY FINDINGS: We found that curcumol effectively inhibited CRC cells from proliferating via the PTEN/PI3K/Akt pathways and reduced expression of miR-21 both in vitro and in vivo. miR-21 mimics were found to decrease the protein level of PTEN and increase the expression of PI3K, phospho-Akt (p-Akt) and NF-kappaB, while miR-21 sponge (miR-21-SP) enhanced the expression of PTEN and reduced the activity of PI3K, Akt and NF-kappaB. Furthermore, miR-21-SP strengthened the role of curcumol in up-regulating PTEN and inhibiting PI3K/Akt pathways, but miR-21 reversed the effect of curcumol on the PTEN/PI3K/Akt pathways. SIGNIFICANCE: Our research demonstrated that curcumol reduced the proliferation of CRC cells through PTEN/PI3K/Akt by targeting miR-21 and miR-21 could be a target molecule of curcumol for CRC treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30686821,"Year":2019,"Title":"Early modifications of circulating microRNAs levels in metastatic colorectal cancer patients treated with regorafenib.","Abstract":"Biomarkers able to improve the cost/benefit ratio are urgently needed for metastatic colorectal cancer patients that are eligible to receive regorafenib. Here, we measured plasma levels of ten circulating microRNAs (c-miRNAs) and we investigated their early changes during treatment, as well as possible correlation with clinical outcome. Ten literature-selected c-miRNAs were quantified by qRT-PCR on plasma samples collected at baseline (d1) and after 15 days of treatment (d15). C-miRNAs showing significant changes were further analyzed to establish correlations with outcome. A decision tree-based approach was employed to define a c-miRNA signature able to predict the outcome. Results achieved in an exploratory cohort were tested in a validation group. In the exploratory cohort (n = 34), the levels of c-miR-21 (p = 0.06), c-miR-141 (p = 0.04), and c-miR-601 (p = 0.01) increased at d15 compared with d1. A c-miRNA signature involving c-miR-21, c-miR-221, and c-miR-760 predicted response to treatment (p < 0.0001) and was significantly associated to PFS (HR = 10.68; 95% CI 3.2-35.65; p < 0.0001). In the validation cohort (n = 36), the increase in c-miR-21 (p = 0.02) and c-miR-601 (p = 0.02) levels at d15 was confirmed, but the associations with outcome were not. Our data indicate that early changes of c-miRNA levels might be influenced by regorafenib treatment. However, further studies are needed to establish the predictive power of such modifications.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30681889,"Year":2019,"Title":"SAV1, regulated by microRNA-21, suppresses tumor growth in colorectal cancer.","Abstract":"This study investigated the role and action of the Salvador 1 protein (SAV1, also called WW45) in colorectal cancer (CRC). For this, CRC SW480 and HCT116 cells were infected with lentiviruses of SAV1 overexpression vector (lenti-SAV1) and SAV1 short hairpin RNA (sh-SAV1) to overexpress and silence SAV1 respectively, or transfected with microRNA-21 (miR-21) mimic to overexpress miR-21. Relative mRNA levels of SAV1 and relative miR-21 levels in CRC tissues or cells were detected. The effects of SAV1 and miR-21 on cell proliferation and apoptosis were evaluated using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and annexin V - fluorescein isothiocyanate (FITC) - propidium iodide (PI) flow cytometry, respectively. Our results revealed that SAV1 was downregulated in CRC tissues compared with the adjacent noncancerous tissues. Furthermore, SAV1 overexpression inhibited proliferation and promoted apoptosis in SW480 and HCT116 cells, whereas knockdown of SAV1 exerted the opposite effect. Additionally, the tumorigenesis of SW480 cells in xenografted mice was significantly inhibited by SAV1 overexpression but promoted by SAV1 knockdown. MiR-21 levels significantly and negatively correlated with SAV1 expression in CRC tissues. More importantly, miR-21 overexpression significantly abolished the SAV1-mediated inhibition of proliferation and stimulation of apoptosis of SW480. In conclusion, SAV1 suppresses tumor growth in CRC and is regulated by miR-21.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30670982,"Year":2018,"Title":"Plasma MicroRNA Pair Panels as Novel Biomarkers for Detection of Early Stage Breast Cancer.","Abstract":"Introduction: Breast cancer is the second leading cause of cancer death among females. We sought to identify microRNA (miRNA) markers in breast cancer, and determine whether miRNA expression is predictive of early stage breast cancer. The paired panel of microRNAs is promising. Methods: Global miRNA expression profiling was performed on three pooling samples of plasma from breast cancer, benign lesion and normal, using next generation sequencing technology. Thirteen microRNAs (hsa-miR-21-3p, hsa-miR-192-5p, hsa-miR-221-3p, hsa-miR-451a, hsa-miR-574-5p, hsa-miR-1273g-3p, hsa-miR-152, hsa-miR-22-3p, hsa-miR-222-3p, hsa-miR-30a-5p, hsa-miR-30e-5p, hsa-miR-324-3p, and hsa -miR-382-5p) were subsequently validated using real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) in a cohort of 53 breast cancer, 40 benign lesions and 38 normal cases. The pairwise miRNA ratios were calculated as biomarkers to classify breast cancer. Results: According to the model used to predict breast cancer from benign lesions, a panel of five miRNA pairs had high diagnostic power with an AUC of 0.942. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of this model after 10-fold cross validation were 0.881, 0.775, 0.827, and 0.756, respectively. In addition, the other panels of miRNA pairs distinguishing the breast cancer from normal and non-cancer patients had good performance. Conclusion: Certain MicroRNA pairs were identified and deemed effective in breast cancer screening, especially when distinguishing cancer from benign lesions.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30604369,"Year":2019,"Title":"Epigenetic Alternations of MicroRNAs and DNA Methylation Contribute to Liver Metastasis of Colorectal Cancer.","Abstract":"BACKGROUND: Liver metastasis is a major cause of mortality in colorectal cancer (CRC). Epigenetic alternations could serve as biomarkers for cancer diagnosis and prognosis. In this study, we analyzed microarray data in order to identify core genes and pathways which contribute to liver metastasis in CRC under epigenetic regulations. MATERIALS AND METHODS: Data of miRNAs (GSE35834, GSE81582), DNA methylation (GSE90709, GSE77955), and mRNA microarrays (GSE68468, GSE81558) were downloaded from GEO database. Differentially expressed genes (DEGs), differentially expressed miRNAs (DEMs), and differentially methylated genes (DMGs) were obtained by GEO2R. The target genes of DEMs were predicted by miRWalk. Functional and enrichment analyses were conducted by DAVID database. Protein-protein interaction (PPI) network was constructed in STRING and visualized using Cytoscape. RESULTS: In liver metastasis, miR-143-3p, miR-10b-5p, miR-21-5p, and miR-518f-5p were down-regulated, while miR-122-5p, miR-885-5p, miR-210-3p, miR-130b-5p, miR-1275, miR-139-5p, miR-139-3p, and miR-1290 were up-regulated compared with primary CRC. DEGs targeted by altered miRNAs were enriched in pathways including complement, PPAR signaling, ECM-receptor interaction, spliceosome, and focal adhesion. In addition, aberrant DNA methylation-regulated genes showed enrichment in pathways of amino acid metabolism, calcium signaling, TGF-beta signaling, cell cycle, spliceosome, and Wnt signaling. CONCLUSION: Our study identified a series of differentially expressed genes which are associated with epigenetic alternations of miRNAs and DNA methylation in colorectal liver metastasis. Up-regulated genes of SLC10A1, MAPT, SHANK2, PTH1R, and C2, as well as down-regulated genes of CAB39, CFLAR, CTSC, THBS1, and TRAPPC3 were associated with both miRNA and DNA methylation, which might become promising biomarker of colorectal liver metastasis in future.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30598580,"Year":2018,"Title":"Relationship between Fusobacterium nucleatum, inflammatory mediators and microRNAs in colorectal carcinogenesis.","Abstract":"AIM: To examine the effect of Fusobacterium nucleatum (F. nucleatum) on the microenvironment of colonic neoplasms and the expression of inflammatory mediators and microRNAs (miRNAs). METHODS: Levels of F. nucleatum DNA, cytokine gene mRNA (TLR2, TLR4, NFKB1, TNF, IL1B, IL6 and IL8), and potentially interacting miRNAs (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p, miR-135b-5p) were measured by quantitative polymerase chain reaction (qPCR) TaqMan((R)) assays in DNA and/or RNA extracted from the disease and adjacent normal fresh tissues of 27 colorectal adenoma (CRA) and 43 colorectal cancer (CRC) patients. KRAS mutations were detected by direct sequencing and microsatellite instability (MSI) status by multiplex PCR. Cytoscape v3.1.1 was used to construct the postulated miRNA:mRNA interaction network. RESULTS: Overabundance of F. nucleatum in neoplastic tissue compared to matched normal tissue was detected in CRA (51.8%) and more markedly in CRC (72.1%). We observed significantly greater expression of TLR4, IL1B, IL8, and miR-135b in CRA lesions and TLR2, IL1B, IL6, IL8, miR-34a and miR-135b in CRC tumours compared to their respective normal tissues. Only two transcripts for miR-22 and miR-28 were exclusively downregulated in CRC tumour samples. The mRNA expression of IL1B, IL6, IL8 and miR-22 was positively correlated with F. nucleatum quantification in CRC tumours. The mRNA expression of miR-135b and TNF was inversely correlated. The miRNA:mRNA interaction network suggested that the upregulation of miR-34a in CRC proceeds via a TLR2/TLR4-dependent response to F. nucleatum. Finally, KRAS mutations were more frequently observed in CRC samples infected with F. nucleatum and were associated with greater expression of miR-21 in CRA, while IL8 was upregulated in MSI-high CRC. CONCLUSION: Our findings indicate that F. nucleatum is a risk factor for CRC by increasing the expression of inflammatory mediators through a possible miRNA-mediated activation of TLR2/TLR4.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30575905,"Year":2018,"Title":"The ratio of miR-21/miR-24 as a promising diagnostic and poor prognosis biomarker in colorectal cancer.","Abstract":"OBJECTIVE: Optimal management of cancer treatment will be guided by sensitive and specific biomarkers. Searching for potential biomarkers is always a hot spot in cancer research, including colorectal cancer (CRC). MicroRNAs (miRNAs) have been recently proposed as biomarkers for cancers. PATIENTS AND METHODS: Based on previous miRNA analysis in our hospital and data mining, we hypothesized that the ratio of miR-21/miR-24 (miR-21/24) may serve as plasma biomarkers in CRC patients. The plasma levels of miR-21 and miR-24 were analyzed from the 186 CRC patients before surgery and 97 healthy controls by qRT-PCR. Receiver operating characteristic (ROC) analysis was further used to evaluate the difference in diagnostic accuracy associated with the expression of miR-21, miR-24 and their ratio. Chi-square2-test or Fisher's exact test was performed to determine the relationship between the ratio of miR-21/24 and clinicopathological parameters. Kaplan-Meier and log-rank testing were performed to evaluate the effect of miR-21/24 ratio on the survival of colon cancer. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated by Cox regression models. RESULTS: ROC curves revealed that the diagnostic accuracy AUC (area under the curve) in CRC tissue of miR-24, miR-21, and the ratio of miR-21/24 were 0.8971, 0.9128 and 0.9875, respectively. Notably, the ratio of miR-21/24, with the best accuracy among these miRNAs, was significantly correlated with several important prognosis factors in CRC, such as tumor size, TNM stage, lymph metastasis and histologic differentiation (all p<0.05). By Kaplan-Meier survival analysis and Cox regression analysis, the ratio of miR-21/24 was shown to be a significant survival risk factor for CRC patients. CONCLUSIONS: We showed that the plasma ratio of miR-21/24 is a potentially powerful tool for detecting CRC and predicting prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30569605,"Year":2019,"Title":"Genetic variant in miR-21 binding sites is associated with colorectal cancer risk.","Abstract":"Single nucleotide polymorphisms (SNPs) within binding sites of microRNAs (miRNAs) could modify cancer susceptibility by changing the binding affinity of miRNAs on their target mRNA 3'-untranslated regions (UTRs). MicroRNA-21 (miR-21) is involved in the development of colorectal cancer. However, the relationship between SNPs within the binding sites of miR-21 and colorectal cancer risk has not been widely investigated. A case-control study including 1147 patients and 1203 controls was performed to evaluate the association of SNPs in miR-21 binding sites and colorectal cancer risk. Dual-luciferase reporter assays and functional assays were performed to evaluate the effects of miR-21. The SNP rs6504593 C allele conferred an increased risk of colorectal cancer compared with the T allele in an additive model (odds ratio [OR] = 1.19, 95% confidence interval [CI] = 1.04-1.36, P = 0.011). Dual-luciferase reporter assays demonstrated that the rs6504593 T allele negatively post-transcriptionally regulated IGF2BP1 by altering the binding affinity of miR-21. Additionally, colorectal cancer cells transiently transfected with miR-21 mimics promoted cell proliferation and suppressed apoptosis, whereas inhibition of miR-21 decreased cell growth. These data suggest that the miR-21 binding site SNP rs6504593 in the IGF2BP1 3'-UTR may alter IGF2BP1 expression and contribute to colorectal cancer risk.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30417287,"Year":2018,"Title":"Non-Invasive Evaluation of Extracellular Matrix Formation in the Intestinal Epithelium.","Abstract":"Differentiation of colorectal cancer Caco-2 cells was assessed using Affymetrix Human Gene 1.0 ST arrays and by the main electrical parameters measured by bioimpedance spectroscopy. Transepithelial electrical resistance (TEER) was maximum on day 7, then decreased by day 11, and remained stable. The baseline resistance was maximum on day 4, minimum on day 7, but then gradually increased over 2 weeks, which can be explained by the formation of the basement membrane components or the apical mucous layer. Caco-2 cells express components of laminin-111 and laminin-511. A synchronous increase in the expression of mucin 3 mRNA (MUC3A/MUC3B) and mucin 17 mRNA (MUC17) and reduced expression of miR-21 and miR-622 microRNA genes were observed. Possible use of the described approach for studying the formation of extracellular matrix is discussed.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30401711,"Year":2019,"Title":"M2 Macrophage-Derived Exosomes Promote Cell Migration and Invasion in Colon Cancer.","Abstract":"Clinical and experimental evidence has shown that tumor-associated macrophages promote cancer initiation and progression. However, the macrophage-derived molecular determinants that regulate colorectal cancer metastasis have not been fully characterized. Here, we demonstrate that M2 macrophage-regulated colorectal cancer cells' migration and invasion is dependent upon M2 macrophage-derived exosomes (MDE). MDE displayed a high expression level of miR-21-5p and miR-155-5p, and MDE-mediated colorectal cancer cells' migration and invasion depended on these two miRNAs. Mechanistically, miR-21-5p and miR-155-5p were transferred to colorectal cancer cells by MDE and bound to the BRG1 coding sequence, downregulating expression of BRG1, which has been identified as a key factor promoting the colorectal cancer metastasis, yet is downregulated in metastatic colorectal cancer cells. Collectively, these findings show that M2 macrophages induce colorectal cancer cells' migration and invasion and provide significant plasticity of BRG1 expression in response to tumor microenvironments during malignant progression. This dynamic and reciprocal cross-talk between colorectal cancer cells and M2 macrophages provides a new opportunity for the treatment of metastatic colorectal cancer. SIGNIFICANCE: These findings report a functional role for miRNA-containing exosomes derived from M2 macrophages in regulating migration and invasion of colorectal cancer cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30388154,"Year":2018,"Title":"miR-21, miR-99b and miR-375 combination as predictive response signature for preoperative chemoradiotherapy in rectal cancer.","Abstract":"INTRODUCTION: Preoperative chemoradiotherapy (CRT) is a standard treatment for locally advanced rectal cancer patients. Despite the benefits of CRT, its use in non-responder patients can be associated with increased toxicities and surgical resection delay. The identification of CRT response biomarkers, such as microRNAs, could improve the management of these patients. We have studied the microRNA expression in pretreatment endoscopy biopsies from rectal cancer patients treated with CRT to identify potential microRNAs able to predict CRT response and clinical outcome of these patients. MATERIAL AND METHODS: RNA from pretreatment endoscopy biopsies from 96 rectal cancer patients treated with preoperative CRT were studied. Pathological response was graded according to the tumor regression grade (TRG) Dworak classification. In the screening phase, 377 miRNAs were studied in 12 patients with extreme responses (TRG0-1 vs TRG4). The potential role as predictive biomarkers for CRT response, disease-free survival (DFS) and overall survival (OS) of the miRNAs identified in the screening phase were validated in the whole cohort. RESULTS: In the screening phase, an 8-miRNAs CRT-response signature was identified: let-7b, let-7e, miR-21, miR-99b, miR-183, miR-328, miR-375 and miR-483-5p. In the validation phase, miR-21, miR-99b and miR-375 emerged as CRT response-related miRNAs while miR-328 and let-7e emerged as prognostic markers for DFS and OS. Interestingly, ROC curve analysis showed that the combination of miR-21, miR-99b and miR-375 had the best capacity to distinguish patients with maximum response (TRG4) from others. CONCLUSIONS: miR-21, miR-99b and miR-375 could add valuable information for individualizing treatment in locally advanced rectal cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30381824,"Year":2019,"Title":"Detection of circulating microRNAs with Ago2 complexes to monitor the tumor dynamics of colorectal cancer patients during chemotherapy.","Abstract":"Because of the different forms of circulating miRNAs in plasma, Argonaute2 (Ago2)-miRNAs and extracellular vesicles (EV-miRNAs), we examined the two forms of extracellular miRNAs in vitro and developed a unique methodology to detect circulating Ago2-miRNAs in small volumes of plasma. We demonstrated that Ago2-miR-21 could be released into the extracellular fluid by active export from viable cancer cells and cytolysis in vitro. As miR-21 and miR-200c were abundantly expressed in both metastatic liver sites and primary lesions, we evaluated Ago2-miR-21 as a candidate biomarker of both active export and cytolysis while Ago2-miR-200c as a biomarker of cytolysis in plasma obtained from colorectal cancer (CRC) patients before treatment and in a series of plasma obtained from CRC patients with liver metastasis who received systemic chemotherapy. The measurement of Ago2-miR-21 allowed us to distinguish CRC patients from subjects without CRC. The trend in DeltaCt values for Ago2-miR-21 and -200c during chemotherapy could predict tumor response to ongoing treatment. Thus, capturing circulating Ago2-miRNAs from active export can screen patients with tumor burdens, while capturing them from passive release by cytolysis can monitor tumor dynamics during chemotherapy treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30361805,"Year":2018,"Title":"miR-21 expression analysis in budding colon cancer cells by confocal slide scanning microscopy.","Abstract":"MicroRNA-21 (miR-21) expression in stromal fibroblastic cells in colorectal cancer is well-documented, whereas miR-21 expression in tumor budding cells (TBCs) is poorly described. TBCs are locally invasive carcinoma cells with increased metastatic properties and characteristics of epithelial to mesenchymal transition. This study was conducted to better characterize the expression of miR-21 in TBCs. First, chromogenic miR-21 in situ hybridization (ISH) staining was performed in 58 colon adenocarcinomas with evident TBCs. Then, to obtain unambiguous identification of miR-21 in the TBCs, twenty cases were selected for an additional multiplex fluorescence analysis combining miR-21 ISH with cytokeratin and laminin-5gamma2 immunofluorescence. Employing confocal slide scanning microscopy, comprehensive digital images of the invasive front (10-40 mm(2)) were obtained from 16 of the 20 cases, and miR-21 expression was evaluated in cytokeratin-positive TBCs. The high resolution of the confocal digital slide images allowed a detailed examination of the confocal stacks of the multiplex-stained tissue sections. The cases with the highest fraction of miR-21 positive TBCs were all stage III cancers defined by the presence of regional lymph node metastasis. Some of the miR-21 positive TBCs were also laminin-5gamma2 positive. The confocal image stacks also revealed that some TBCs were actually directly connected to malignant glands. In conclusion, miR-21 expression was unambiguously identified in TBCs by evaluation of digital slides obtained by confocal slide scanning microscopy. In addition, the digital confocal slides provided a more detailed understanding of local cancer cell invasion by allowing evaluation of the cell structures in three dimensions.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30357530,"Year":2019,"Title":"Role of miRNA-210, miRNA-21 and miRNA-126 as diagnostic biomarkers in colorectal carcinoma: impact of HIF-1alpha-VEGF signaling pathway.","Abstract":"Colorectal cancer (CRC) is a major cause of death worldwide. Novel non-invasive, high diagnostic value screening test is urgently needed to improve survival rate, treatment and prognosis. Stable, small, circulating microRNA (miRNA) offers unique opportunities for the early diagnosis of several diseases. It acts as tumor oncogenes or suppressors and involve in cell death, survival, and metastasis. Communication between miRNA and carcinogenesis is critical but it still not clear and needs further investigation. The aim of our study is to evaluate the role of miR-210, miR-21, miR-126, as non-invasive diagnostic biomarkers for screening, early detection of CRC, studying their correlation with prognostic variables, and clarifying the roles of miRNAs on HIF-1alpha-VEGF signaling pathway. The expression of miR-210, miR-21 and miR-126 was performed using qRT-PCR in adenocarcinoma (no = 35), adenomas (no = 51), and neoplasm free controls (no = 101). Serum levels of VEGF and HIF-1alpha was determined by ELISA Kit. The results show that the expression of miR-210, miR-21, VEGF, HIF-1alpha was significantly up-regulated while that miRNA-126 was down-regulated in both adenocarcinoma and adenomas compared with controls (p < 0.001 for each). No significant difference was noted comparing patients with adenocarcinoma and adenomas. The three miRNAs correlated with VEGF, HIF-alpha. The miR-210 and miR-21 associated with TNM classification and clinical staging of adenocarcinoma (p < 0.001) and they show high diagnostic value with sensitivity and specificity 88.6%, 90.1% and 91.4%, 95.0% respectively. Our study revealed that circulating miR-210, miR-21 were up-regulated while miR-126 was down-regulated in CRC and adenomas patients, they all correlated with TNM staging and they had high diagnostic value. HIF-1alpha VEGF signaling pathways regulated by miRNAs played a role in colon cancer initiation. To the best of our knowledge, this is the first study of this miRNAs panel in CRC in our community. These data suggested that these biomarkers could be a potential novel, non-invasive marker for early diagnosis, screening and predicting prognosis of CRC. Understanding the molecular functions by which miRNAs affect cancer and understanding its roles in modulating the signaling output of VEGF might be fruitful in reducing the incidence and slowing the progression of this dark malignancy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30348685,"Year":2018,"Title":"Expression of Circulating miR-155, miR-21, miR-221, miR-30a, miR-34a and miR-29a: Comparison of Colonic and Rectal Cancer.","Abstract":"BACKGROUND: Colorectal cancer is an increasing cause of death. Circulating microRNAs (miRs) could be great diagnostic and prognostic biomarkers of colorectal cancer, but further continuation of their utility is needed for their comprehensive application. MATERIALS AND METHODS: Twenty-seven patients with colonic cancer, 16 with rectal cancer and 12 healthy volunteers as controls, were involved in this study. Expression of miR-155, miR-21, miR-221, miR-30a, miR-34a and miR-29a were determined by reverse transcription polymerase chain reaction (RT-PCR) from sera of patients. RESULTS: Expression of miR-155, miR-21 and miR-221 was significantly higher in rectal cancer than in colonic cancer. There was no difference found between those with TNM1 cancer and controls for both cancer types. miR-155, miR-34a and miR-29a were down-regulated in all patients with cancer compared to controls. We did not find any statistically significant up-regulation of miR-221 in patients with colonic cancer compared to controls. In contrast, in patients with rectal cancer, miR-221 expression was higher than in controls. Advanced stage was also linked to higher miR-221 expression compared to early stage. Slight, but statistically significant increase was observed in miR-30a expression in patients with colon cancer compared to control individuals. CONCLUSION: Our results partly support previous findings. Here we report on differences in the expression of circulating microRNA between colonic and rectal tumours for the first time.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30336280,"Year":2018,"Title":"Prognostic significance of circulating microRNA-21 expression in esophageal, pancreatic and colorectal cancers; a systematic review and meta-analysis.","Abstract":"BACKGROUND: Literature has shown that aberrantly expressed microRNAs may have implications in certain cancers. A wealth of studies signal potential prognostic role of microRNA-21 in GIT cancers. This meta-analysis quantitatively determines prognostic significance of circulating microRNA-21 in esophageal squamous cell carcinoma (ESCC), pancreatic ductal adenocarcinoma (PDAC) and colorectal carcinoma (CRC). METHODS: Databases of Medline, Wiley online library, Cochrane library, Taylor and Francis Online, CINAHL, Springer, Proquest, ISI Web of knowledge, ScienceDirect, and Emerald were searched using MeSH terms serum/tissue microRNA-21, prognosis, esophagus squamous cell carcinoma, pancreatic ductal adenocarcinoma, colorectal cancer. A systematic algorithm was used that selected 15 relevant studies. Meta-analysis was conducted using forest plot and a summary effect model was employed. RESULTS: This meta-analysis reports significant prognostic value of miR-21 in predicting worse overall survival (OS) in ESCC, PDAC, and CRC with pooled hazard ratio (HR) of 3.49 (95% CI 2.58-4.71, p-value<0.01). Subgroup analysis for ESCC showed a pooled HR of 3.46 (95% CI 1.88-635, p value of <0.01), worse overall survival (OS) with the pooled HR of 3.14 (95% CI 2.22-4.43, p value<0.01) for CRC and a pooled HR of 3.77 (95% CI 1.63-8.73, p value<0.01) for PDAC. CONCLUSION: This research infers that microRNA-21 expression is a powerful prognostic tool. Expression of micro-RNA-21 is associated with poor OS and poorer disease-free survival in ESCC, PDAC and CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30332981,"Year":2019,"Title":"Deregulation of miR-21 and miR-29a in Cervical Cancer Related to HPV Infection.","Abstract":"BACKGROUND: Early diagnosis is an important factor to improve the survival of Invasive Cervical Cancer (ICC) patients. Molecular biomarkers such as micro RNA (miRNA) can be used in the early detection of ICC. The expression of miR-21 and miR-29a are deregulated in many types of human cancers. OBJECTIVE: The aim of this study was to investigate the differences in miR-21 and miR-29a expression patterns in the Human Papilloma Virus (HPV) infection and various grades of cervical cancer among Iranian women. METHODS: Small RNAs were extracted from positive for HPV, cervical cancer and healthy samples from 43, 50 and 46 individuals, respectively. Expression levels of miR-21 and miR-29a were analyzed by SYBR Green real-time RT-PCR using specific primers, and 5s rRNA as the internal reference gene. RESULTS: Results have shown a significant increase in miR-21 and decrease in miR-29 in cancerous samples in comparison with the control groups (P < 0.0001). CONCLUSION: This study illustrated that miR-21 and miR-29a could be operated as an oncogene and tumor-suppressor in cervical cancer progression. More studies are needed to demonstrate the role of miR-21 and miR-29a as potential biomarkers for the diagnosis of cervical cancer in future investigations.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30239392,"Year":2018,"Title":"MiR-486-5p Downregulation Marks an Early Event in Colorectal Carcinogenesis.","Abstract":"BACKGROUND: MicroRNAs are dysregulated in colorectal cancer and subsets correlated with advanced tumor stage and metastasis. Data are lacking on microRNA dysregulation from early to late-stage disease. OBJECTIVE: The purpose of this study was to identify a microRNA signature associated with the primary tumor and metastatic site in stage IV disease and to examine whether the signature is evident in earlier stages. DESIGN: A microRNA profile was generated and then explored in normal colon tissue (n = 5), early stage (stage I and II; n = 10), and late-stage (stage III and IV; n = 14) colorectal primary tumors via polymerase chain reaction to delineate molecular events that may promote colorectal carcinogenesis. SETTING: Genome-wide microRNA expression profiling was performed. PATIENTS: A total of 14 patient-matched stage IV primary colorectal cancer tumors and corresponding liver metastases were included. MAIN OUTCOME MEASURES: MicroRNA array technology was used to identify microRNA expression-predictive metastatic potential in the primary tumor. RESULTS: A distinct 9-member signature group of microRNAs was concurrent in stage IV primary colorectal cancer and their corresponding liver metastases, when compared with surrounding unaffected colon and liver tissue (microRNA-18b, microRNA-93, microRNA-182, microRNA-183, microRNA21, microRNA-486-5p, microRNA-500a, microRNA-552, and microRNA-941). Of the microRNA panel, only microRNA486-5p was differentially expressed in early stage colorectal cancer samples compared with normal tissue (p = 0.001) and additionally differentially expressed between late-stage colorectal cancer samples and normal tissue (p < 0.01). LIMITATIONS: Our microRNA profile was generated in a small subset of patients and will require validation in more samples. CONCLUSIONS: We identified a distinct microRNA signature in primary colon and matched metastatic disease. On additional investigation, 1 microRNA was differentially expressed in both early and late-stage cancer patient samples, and it may herald an early event in colorectal carcinogenesis. This study warrants additional investigation with a larger patient cohort to better understand the effect of microRNAs in carcinogenesis. See Video Abstract at http://links.lww.com/DCR/A723.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30226598,"Year":2018,"Title":"miR215p targets PDHA1 to regulate glycolysis and cancer progression in gastric cancer.","Abstract":"Pyruvate dehydrogenase A1 (PDHA1) is a component of the pyruvate dehydrogenase enzyme complex, which links glycolysis and the tricarboxylic acid cycle, and is important for cancer metabolism shift. PDHA1 downregulation has been revealed in several types of cancer to enhance glycolysis. However, the role of PDHA1 in gastric cancer remains largely unknown. In the present study, we found that PDHA1 was significantly downregulated in gastric cancer, and associated with poor prognosis. PDHA1 downregulation promoted gastric cancer glycolysis and cancer progression. miR215p directly targeted PDHA1 to suppress PDHA1 expression, and promote glycolysis as well as cell proliferation in gastric cancer. Moreover, miR215p was significantly upregulated in gastric cancer and negatively associated with PDHA1 expression in gastric cancer samples. Our results indicated that miR215p targeted PDHA1 to regulate a metabolic switch and cancer progression in gastric cancer, and reveal the potential role of the miR215p/PDHA1 axis in gastric cancer treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30213464,"Year":2018,"Title":"MiRNAs as molecular biomarkers in stage II egyptian colorectal cancer patients.","Abstract":"AIM: To assess the role of aberrant miRNAs expressions in stage II CRC patients from Egypt. METHODS: Tumor tissue samples were obtained from 124 CRC stage II patients compared to 100 healthy controls for assessing miRNAs expression using; 1) a cataloged 84-miRNAs PCR array panel, and 2) another five miRNAs (miR-21, miR-137, miR-145, miR-320 and miR-498) that have been reported in previous studies to have a role in CRC, by quantitative real time PCR (qPCR). The results were correlated to patients' characteristics, response to treatment and survival. RESULTS: There were 17 out of 84 miRNAs differentially expressed in the CRC patients. Twenty six miRNAs were significantly differentially expressed in the female CRC patients, while 16 miRNAs were significantly differentially expressed in the male CRC patients. Only, five miRNAs (miR-21, Let-7a-5p, miR-100-5p, miR-200c-3p and miR-23b-3p) were significantly common deregulated in CRC patients regardless gender. miR-21 was overexpressed in 48.4% of the patients and it was significantly downregulated in females and over expressed in males. In univariate analysis; performance status, over-expression of miR-21 and miR-498 and reduced miR-137, miR-145, and miR-320 associated significantly with reduced DFS and OS whereas in multivariate analysis; miR-498 and miR-320 were independent prognostic factors for DFS and miR-21 was independent prognostic factors for OS. CONCLUSION: miRNAs expression differs significantly between male and female stage II CRC patients, miR-21, Let-7a-5p, miR-100-5p, miR-200c-3p and miR-23b-3p could be used as common diagnostic biomarkers for CRC. On the other hand, a three miRNAs panel (miR-21, miR-498 and miR-320) can predict recurrence and survival in those patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30212824,"Year":2018,"Title":"The CircRNA-ACAP2/Hsa-miR-21-5p/ Tiam1 Regulatory Feedback Circuit Affects the Proliferation, Migration, and Invasion of Colon Cancer SW480 Cells.","Abstract":"BACKGROUND/AIMS: Circular RNAs (circRNAs), a type of RNA that is widely expressed in human cells, have essential roles in the development and progression of cancer. CircRNAs contain microRNA (miRNA) binding sites and can function as miRNA sponges to regulate gene expression by removing the inhibitory effect of an miRNA on its target gene. METHODS: We used the bioinformatics software TargetScan and miRanda to predict circRNA-miRNA and miRNAi-Mrna interactions. Rate of inhibiting of proliferation was measured using a WST-8 cell proliferation assay. Clone formation ability was assessed with a clone formation inhibition test. Cell invasion and migration capacity was evaluated by performing a Transwell assay. Relative gene expression was assessed using quantitative real-time polymerase chain reaction and relative protein expression levels were determined with western blotting. circRNA and miRNA interaction was confirmed by dual-luciferase reporter and RNA-pull down assays. RESULTS: In the present study, the miRNA hsa-miR-21-5p was a target of circRNA-ACAP2, and T lymphoma invasion and metastasis protein 1 (Tiam1) was identified as a target gene of hsa-miR-21-5p. CircRNA-ACAP2 and Tiam1 were shown to be highly expressed in colon cancer tissue and colon cancer SW480 cells, but miR-21-5p was expressed at a low level. SW480 cell proliferation was suppressed when the expression of circRNA-ACAP2 and Tiam1 was decreased and the expression of miR-21-5p was increased in vivo and in vitro. SW480 cell migration and invasion were also inhibited under the same circumstance. The circRNA-ACAP2 interaction regulated the expression of miR-21-5p, and miR-21-5p regulated the expression of Tiam1. Down-regulation of circRNA-ACAP2 promoted miR-21-5p expression, which further suppressed the transcription and translation of Tiam1. CONCLUSION: The present study shows that the circRNA-ACAP2/hsa-miR-21-5p/Tiam1 regulatory feedback circuit could affect the proliferation, migration, and invasion of colon cancer SW480 cells. This was probably due to the fact that circRNA-ACAP2 could act as a miRNA sponge to regulate Tiam1 expression by removing the inhibitory effect of miR-21-5p on Tiam1 expression. The results from this study have revealed new insights into the pathogenicity of colon cancer and may provide novel therapeutic targets for the treatment of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30184100,"Year":2018,"Title":"Colorectal cancer-derived small extracellular vesicles establish an inflammatory premetastatic niche in liver metastasis.","Abstract":"Liver metastases develop in more than half of the patients with colorectal cancer (CRC) and are associated with a poor prognosis. The factors influencing liver metastasis of CRC are poorly characterized, but this information is urgently needed. We have now discovered that small extracellular vesicles (sEVs; exosomes) derived from CRC can be specifically targeted to liver tissue and induce liver macrophage polarization toward an interleukin-6 (IL-6)-secreting proinflammatory phenotype. More importantly, we found that microRNA-21-5p (miR-21) was highly enriched in CRC-derived sEVs and was essential for creating a liver proinflammatory phenotype and liver metastasis of CRC. Silencing either miR-21 in CRC-sEVs or Toll-like receptor 7 (TLR7) in macrophages, to which miR-21 binds, abolished CRC-sEVs' induction of proinflammatory macrophages. Furthermore, miR-21 expression in plasma-derived sEVs was positively correlated with liver metastasis in CRC patients. Collectively, our data demonstrate a pivotal role of CRC-sEVs in promoting liver metastasis by inducing an inflammatory premetastatic niche through the miR-21-TLR7-IL-6 axis. Thus, sEVs-miR-21 represents a potential prognostic marker and therapeutic target for CRC patients with liver metastasis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30134821,"Year":2018,"Title":"Overexpression of miR-21-5p promotes proliferation and invasion of colon adenocarcinoma cells through targeting CHL1.","Abstract":"BACKGROUND: This study aims to investigate the effect of miR-21-5p on process of colon adenocarcinoma (COAD) cells and its connection with neural cell adhesion molecule L1 (CHL1). METHODS: Different expressions of mRNAs and miRNAs were calculated with microarray analysis. QRT-PCR and western blot were performed to quantify miR-21-5p and CHL1 expression. Flow Cytometry, MTT assay, colony formation assay, transwell assay and ELISA were performed to evaluate propagation and invasiveness of COAD cells. Dual luciferase reporter assay was employed to scrutinize the relationship between miR-21-5P and CHL1. We performed in vivo experiment to detect the impact of miR-21-5p and CHL1 on COAD tumor growth. RESULTS: Expression level of miR-21-5p increased in both COAD tissues and cells. MTT and Cell cycle assay showed that overexpression of miR-21-5p accelerated proliferation of COAD cells. Transwell assay indicated that miR-21-5p promoted cell invasion. The result of dual luciferase reporter assay indicated that miR-21-5p targeted CHL1 directly and inhibited its expression. The result of in vivo experiments showed that down-regulation of miR-21-5p decreased the volume and weight of tumor, while knockdown of CHLI stimulated tumor growth. CONCLUSIONS: The overexpression of miR-21-5p can promote propagation and invasiveness of COAD cells through inhibiting the expression of CHL1.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":30066857,"Year":2018,"Title":"Establishment of three novel cell lines derived from African American patients with colorectal carcinoma: A unique tool for assessing racial health disparity.","Abstract":"The incidence and mortality rates of colorectal carcinoma (CRC) are higher among African Americans (AAs) compared with Caucasian Americans (CAs). To assess the molecular properties associated with racial health disparity, three cell lines derived from colorectal tumors of three AA subjects were established. Cellular and molecular characterization of the cell lines designated CHTN06, SB501 and SB521 was performed using standard technologies, including immunofluorescence, electron microscopy, karyotyping, reverse transcription-polymerase chain reaction, ELISA and immunoblot analysis. The histology and morphology of CHTN06 xenografts were examined by hematoxylin and eosin staining. A total of three AA CRC cell lines derived from primary tumors were established and characterized. These cell lines were successfully cultured without immortalization and were found to be tumorigenic as mouse xenografts. In the present study, immunoblotting and immunofluorescence confirmed the expression of proteins known to be dysregulated in CRC, such as p53, DNA mismatch repair proteins and villin-1. Oncogenic miRNAs (i.e., miR-17, miR-21, miR-182, miR-210 and miR-222) were overexpressed in the AA CRC lines compared with the CA CRC lines (HT-29, HCT116 and SW480). Additionally, the AA CRC cell lines exhibited a differential inflammatory profile compared with HT-29 (CA CRC cell line); specifically noted was IL-8 secretion in response to inflammatory stimuli. In conclusion, three novel cell lines derived from AA CRC tissues were generated. These cell lines were characterized as epithelial in nature and exhibited differential expression of several miRNAs and inflammatory responses compared with commercially available cell lines of CA origin. The CRC cell lines CHTN06, SB501 and SB521 represent novel tools that may be used to provide diverse in vitro and in vivo models for studying CRC and racial health disparity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29936770,"Year":2018,"Title":"[Clinical application value of combined detection of serum miR-378 and miR-21 in gastric cancer].","Abstract":"Objective: To investigate the clinical value of combined detection of serum miR-378 and miR-21 in gastric cancer (GC). Methods: Eighty-seven patients with GC and 78 patients with colorectal cancer(CRC) from National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences were selected, 83 individuals undergoing healthy physical examination were selected as the healthy controls. The levels of serum miR-378 and miR-21 were detected by quantitative real-time PCR (RT-qPCR) (result data were transformed as log2 for analysis). Results: Relative expression levels of miR-378 in the serum were -1.24, -3.25 and -2.73 in healthy controls, GC and CRC patients, respectively. Compared with the healthy controls, the levels of serum miR-378 were significantly decreased in GC and CRC patients (both P<0.05). Relative expression levels of miR-21 in the serum were 0.11, 2.34 and 2.47 in healthy controls, GC and CRC patients, respectively. Compared with the healthy controls, the levels of serum miR-21 were significantly up-regulated in GC and CRC patients (both P<0.05). Moreover, the serum level of miR-378 in GC patients was inversely associated with tumor clinical stage (P<0.05). However, the level of miR-21 showed no significant differences among patients with different clinical and pathological characteristics (all P>0.05). The area under the receiver operating characteristic curve (AUC), sensitivity and specificity of miRNA-378 to diagnose GC was 0.770, 82.0% and 66.0%, respectively, and were 0.900, 85.0%, and 88.0% of miR-21, respectively. The AUC, sensitivity and specificity of combined detection of serum miR-378 and miR-21 to diagnose GC were 0.930, 92.0% and 87.0%, respectively, while the AUC of combined detection of serum CEA and CA-199 was 0.767, the AUC of combined all of the four factors was 0.946. Conclusion: The combined detection of serum miR-378 and miR-21 have a certain effect on diagnosis of GC.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29930763,"Year":2018,"Title":"Extensive screening of microRNA populations identifies hsa-miR-375 and hsa-miR-133a-3p as selective markers for human rectal and colon cancer.","Abstract":"MicroRNAs (miRNAs) are approximately 22-nt molecules exerting control of protein expression in cancer tissues. The current study determined the full spectrum of miRNA dysregulation in freshly isolated human colon or rectal cancer biopsies as well as in controls of healthy adjacent tissue (total of n = 100) using an Illumina sequencing technology. In this work, we aimed to identify miRNAs that may serve as future marker to discern between these two subtypes. DESeq2 analysis revealed 53 significantly dysregulated miRNAs in colon cancer, 67 miRNAs in rectal cancer, and 97 miRNAs in both at a Padj value < 0.05 and >/= 10 read counts. 65% of miRNAs were upregulated in colon as well as rectal cancer. Highest significant dysregulation (Padj < 0.00001) was detected for hsa-miR-21-5p, -215-5p and -378a in both colon and rectal cancer. Among the group of miRNAs with Padj < 0.05 and more than 2-fold expression differences, hsa-miR-375 was detected in rectal cancer only, and hsa-miR-133a-3p only in colon cancer. Receiver operating characteristic (ROC) analysis confirmed highly distinct sensitivities for hsa-miR-375 to detect rectal cancer (area under the curve (AUC): 0.9), while hsa-miR-133a-3p (AUC: 0.89) had the highest sensitivity for detecting colon cancer. We conclude that hsa-miR-375 and hsa-miR-133a-3p may serve as new markers of rectal or colon cancer and should be further investigated to search for different etiologies of colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29928882,"Year":2018,"Title":"CircRNA circ_0026344 as a prognostic biomarker suppresses colorectal cancer progression via microRNA-21 and microRNA-31.","Abstract":"Recently, circular RNA (circRNA) is identified as a novel class of noncoding RNA with important roles in human diseases, such as cancer. However, how circRNA participates in colorectal cancer (CRC) remains unclear. In this study, we aimed to illustrate the role of circ_0026344 in CRC progression. We showed that circ_0026344 expression was downregulated in CRC tissues compared to adjacent normal tissues. Moreover, the level of circ_0026344 was inversely correlated with CRC advance and lymphoid node metastasis. Additionally, circ_0026344 low expression predicted poor prognosis in CRC patients. We identified circ_0026344 as a miRNA sponge for microRNA-21 (miR-21) and microRNA-31 (miR-31) whose expression levels were elevated in CRC tissues. And the level of circ_0026344 was reversely correlated with both miR-21 and miR-31 levels in CRC tissues. Functionally, we found that ectopic expression of circ_0026344 decreased the growth and invasion of CRC cells while promoting apoptosis in vitro. The xenograft experiment indicated that circ_0026344 overexpress led to CRC growth inhibition in vivo. Rescue assays further demonstrated that circ_0026344 exerted biological functions by sponging miR-21 and miR-31 in CRC. In conclusion, this study revealed that circ_0026344/miR-21/miR-31 regulatory signaling was implicated in CRC progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29780253,"Year":2018,"Title":"A 5-serum miRNA panel for the early detection of colorectal cancer.","Abstract":"Objective: The study aimed to screen microRNAs (miRNAs) that can be used for the early detection of colorectal cancer (CRC) based on differential expression of miRNA in serum. Materials and methods: A three-stage study was designed with a total of 217 CRCs, 168 colorectal adenomas (CRAs), and 190 healthy controls (HCs). A quantitative reverse transcription polymerase chain reaction was performed in three stages. We screened 528 miRNA expression profiles in the sera of 40 patients (CRC n=20, CRA n=10, and HC n=10) for candidate miRNAs, then 210 serum samples (CRC n=90, CRA n=60, and HC n=60) were used for screening of candidate miRNAs. Three hundred and twenty-five independent individual samples (CRC n=107, CRA n=98, and HC n=120) were used to validate the most differentially-expressed miRNAs in the screening stage, and binary logistic regression was used in the validation stage. A receiver operating characteristic curve was drawn to evaluate the diagnostic accuracy. Results: A 5-serum miRNA panel (miRNA-1246, miRNA-202-3p, miRNA-21-3p, miRNA-1229-3p, and miRNA-532-3p) effectively distinguished CRCs from HCs with 91.6% sensitivity and 91.7% specificity. The area under the curve (AUC) was 0.960 (95% confidence interval [CI]: 0.937-0.983). In addition, the panel also accurately distinguished CRCs from CRAs with 94.4% sensitivity and 84.7% specificity. The AUC was 0.951 (95% CI: 0.922-0.980). Conclusion: Our 5-serum miRNA panel accurately distinguished CRCs from CRAs and HCs with high sensitivity and specificity. The 5-serum miRNA panel may be a promising prospect for application as a nonintrusive and inexpensive method for the early detection of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29779016,"Year":2018,"Title":"Integrated analysis of colorectal cancer microRNA datasets: identification of microRNAs associated with tumor development.","Abstract":"Colorectal cancer (CRC) is one of the leading cause of cancer death worldwide. Currently, no effective early diagnostic biomarkers are available for colorectal carcinoma. Therefore, there is a need to discover new molecules able to identify pre-cancerous lesions. Recently, microRNAs (miRNAs) have been associated with the onset of specific pathologies, thus the identification of miRNAs associated to colorectal cancer may be used to detect this pathology at early stages. On these bases, the expression levels of miRNAs were analyzed to compare the miRNAs expression levels of colorectal cancer samples and normal tissues in several miRNA datasets. This analysis revealed a group of 19 differentially expressed miRNAs. To establish the interaction between miRNAs and the most altered genes in CRC, the mirDIP gene target analysis was performed in such group of 19 differentially expressed miRNAs. To recognize miRNAs able to activate or inhibit genes and pathways involved in colorectal cancer development DIANA-mirPath prediction analysis was applied. Overall, these analyses showed that the up-regulated hsa-miR-183-5p and hsa-miR-21-5p, and the down-regulated hsa-miR-195-5p and hsa-miR-497-5p were directly related to colorectal cancer through the interaction with the Mismatch Repair pathway and Wnt, RAS, MAPK, PI3K, TGF-beta and p53 signaling pathways involved in cancer development.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29777792,"Year":2018,"Title":"Human cancer cells suppress behaviors of endothelial progenitor cells through miR-21 targeting IL6R.","Abstract":"Deep vein thrombosis (DVT) is a severe clinical process and has a high rate of fatality. Cancer patients have a high incidence rate of venous thrombosis complication and increase the mortality of cancer patients for 2-8 times. The mechanisms involved in human cancers and venous thrombosis remains unclear. In this study, we determined miR-21 expressed higher in human breast cancer, colon cancer and hepatocellular cancer tissues compared with normal tissues and expressed higher in exosomes of breast cancer and hepatocellular cancer cell lines compared with normal cells. MiR-21 dramatically suppressed proliferation, migration and invasion of endothelial progenitor cells (EPCs), which performed promoting role in thrombus repairment and resolution. High levels of miR-21 in exosomes of human cancers dramatically inhibited behaviors of EPCs, and depletion of miR-21 abrogated the decreased proliferation, migration and invasion of EPCs induced by human cancer cells. Moreover, IL6R (interleukin 6 receptor) was identified to be a direct target of miR-21 and promoted cell proliferation, migration and invasion of EPCs. Therefore, the miR-21-IL6R pathway contributed to behaviors of EPCs and consequently mediated the vein thrombosis in patients with cancer. MiR-21-IL6R pathway based therapeutic methods would be beneficial to decrease the complicated venous thrombosis in cancer patients and promote thrombus resolution.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29750053,"Year":2018,"Title":"Prognostic value of microRNAs in colorectal cancer: a meta-analysis.","Abstract":"Background: Numerous studies have shown that miRNA levels are closely related to the survival time of patients with colon, rectal, or colorectal cancer (CRC). However, the outcomes of different investigations have been inconsistent. Accordingly, a meta-analysis was conducted to study associations among the three types of cancers. Materials and methods: Studies published in English that estimated the expression levels of miRNAs with survival curves in CRC were identified until May 20, 2017 by online searches in PubMed, Embase, Web of Science, and the Cochrane Library by two independent authors. Pooled HRs with 95% CIs were used to estimate the correlation between miRNA expression and overall survival. Results: A total of 63 relevant articles regarding 13 different miRNAs, with 10,254 patients were ultimately included. CRC patients with high expression of blood miR141 (HR 2.52, 95% CI 1.68-3.77), tissue miR21 (HR 1.31, 95% CI 1.12-1.53), miR181a (HR 1.52, 95% CI 1.26-1.83), or miR224 (HR 2.12, 95% CI 1.04-4.34), or low expression of tissue miR126 (HR 1.55, 95% CI 1.24-1.93) had significantly poor overall survival (P<0.05). Conclusion: In general, blood miR141 and tissue miR21, miR181a, miR224, and miR126 had significant prognostic value. Among these, blood miR141 and tissue miR224 were strong biomarkers of prognosis for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29673421,"Year":2019,"Title":"Long Noncoding RNA LINC01296 Harbors miR-21a to Regulate Colon Carcinoma Proliferation and Invasion.","Abstract":"Increasing evidence has demonstrated that aberrant expressions of long noncoding RNAs (lncRNAs) are closely correlated to various malignancies, as well as colon carcinoma (CC). The aim of this study was to investigate the role of lncRNA long intergenic noncoding RNA 001296 (LINC01296) in tumorigenesis of CC. The result of the quantitative real-time polymerase chain reaction (qRT-PCR) demonstrated that LINC01296 was upregulated in CC cancerous tissues and cell lines compared to adjacent normal tissue and normal liver cell lines. LINC01296 overexpression was associated with poor prognosis and lower survival rate. Moreover, LINC01296 silencing inhibited the proliferation and invasion of CC cells in vitro detected by epithelial-mesenchymal transition (EMT). Bioinformatics analysis revealed that miR-21a targeted the 3'-UTR of LINC01296. Rescue experiments confirmed that miR21a could reverse the function of LINC01296 on CC cells. Together, our findings indicated that overexpression of LINC01296 is associated with poor survival of CC patients and promotes CC cell progression by regulating miR-21a, providing a prognostic biomarker and therapeutic target.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29633600,"Year":2018,"Title":"The Role of MicroRNA Signature as Diagnostic Biomarkers in Different Clinical Stages of Colorectal Cancer.","Abstract":"OBJECTIVES: Colorectal cancer (CRC) is one of the most common cancers and a major cause of cancer-related death worldwide. The early diagnosis of colorectal tumors is one of the most important challenges in cancer management. MicroRNAs (miRNAs) have provided new insight into CRC development and have been suggested as reliable and stable biomarkers for diagnosis and prognosis. This study's objective was to analyze the differential expression of miRNAs at differentstages of CRC searching for possible correlation with clinicopathological features to examine their potential value as diagnostic biomarkers. MATERIALS AND METHODS: In this case-control study, plasma and matched tissue samples were collected from 74 CRC patients at stage II-IV as well as blood samples from 32 healthy controls. After exhaustive study of the current literature, eight miRNAs including miR-200c, 20a, 21, 31,135b, 133b,145 and let-7g were selected. The expression level of the miRNAs was assayed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Statistical analysis, including t test , Mann-Whitney U, Kruskall-Wallis tests and receiver operating characteristic (ROC) curve was applied, where needed. RESULTS: Significantly elevated levels of miR-21, miR-31, miR-20a, miR-135b, and decreased levels of miR- 200c, miR-145 and let-7 g were detected in both plasma and matched tissue samples compared to the healthy group (P<0.05). However, no significant differences were observed in the expression level of plasma and tissue miR-133b (P>0.05). ROC for tissue miRNAs showed an area under the ROC curve (AUC) of 0.98 and P<0.001 for miR-21, 0.91 and P<0.001 for miR-135b, 0.91 and P<0.001 for miR-31, and 0.92 and P<0.001 for miR-20a. CONCLUSIONS: Our results indicate that the expression levels of microRNAs are systematically altered in CRC tissue and plasma. In conclusion, detection of miR-21, miR-135b, miR-31 and miR-20a levels in the tissue might be helpful to illuminate the molecular mechanisms underlying CRC carcinogenesis and serve as tumor-associated biomarkers for diagnosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29600711,"Year":2018,"Title":"JQ-1 Inhibits Colon Cancer Proliferation via Suppressing Wnt/beta-Catenin Signaling and miR-21.","Abstract":"Bromodoamin and extraterminal (BET) protein inhibitors are a novel class of cancer therapeutics. Here we aim to investigate the efficacy and mechanism of JQ-1, a potent BET inhibitor, in colon cancer therapy. JQ-1 was used to treat SW480 colon cancer mouse xenografts. The tumor size and mouse survival were recorded. Cell apoptosis was evaluated by Annex V-FIC/PI flow cytometry. ChIP-q-PCR analysis was used to assess the H3K27 trimethylation (H3K27m3) of the p16 promoter. Wnt signaling was evaluated by Nkd2 and beta-catenin levels. RT-PCR was used to evaluate the level of miR-21. MiR-21 was overexpressed with a lentiviral system and was used to evaluate the relationship between miR-21 and JQ-1. JQ-1 significantly reduced tumor growth, improved mouse survival, and induced apoptosis. JQ-1 epigenetically inhibited the H3K27me3 promoter activity, promoting p16 expression. Nkd2 and beta-catenin were upregulated and downregulated by JQ-1, respectively. MiR-21 was downregulated by JQ-1. MiR-21 overexpression compensated for proliferation inhibition by JQ-1. Nkd2 levels were also downregulated by miR-21 overexpression. JQ-1 is effective in inhibiting colon cancer. We revealed that the mechanism of JQ-1 action is associated with its regulation of Wnt/beta-catenin signaling and miR-21 levels.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29589310,"Year":2018,"Title":"RT-qPCR for Fecal Mature MicroRNA Quantification and Validation.","Abstract":"By routinely and systematically being able to perform quantitative stem-loop reverse transcriptase (RT) followed by TaqMan(R) minor-groove binding (MGB) probe, real-time quantitative PCR analysis on exfoliated enriched colonocytes in stool, using human (Homo sapiens, hsa) micro(mi)RNAs to monitor changes of their expression at various stages of colorectal (CRC) progression, this method allows for the reliable and quantitative diagnostic screening of colon cancer (CC). Although the expression of some miRNA genes tested in tissue shows less variability in normal or cancerous patients than in stool, the noninvasive stool by itself is well suited for CC screening. An miRNA approach using stool promises to offer more sensitivity and specificity than currently used genomic, methylomic, or proteomic methods for CC screening.To present an application of employing miRNAs as diagnostic markers for CC screening, we carried out global microarray expression studies on stool colonocytes isolated by paramagnetic beads, using Affymetrix GeneChip miRNA 3.0 Array, to select a panel of miRNAs for subsequent focused semiquantitative PCR analysis studies. We then conducted a stem-loop RT-TaqMan(R) MGB probes, followed by a modified real-time qPCR expression study on 20 selected miRNAs for subsequent validation of the extracted immunocaptured total small RNA isolated from stool colonocytes. Results showed 12 miRNAs (miR-7, miR-17, miR-20a, miR-21, miR-92a, miR-96, miR-106a, miR-134, miR-183, miR-196a, miR-199a-3p, and miR214) to have an increased expression in stool of CC patients, and that later TNM stages exhibited more increased expressions than adenomas, while 8 miRNAs (miR-9, miR-29b, miR-127-5p, miR-138, miR-143, miR-146a, miR-222, and miR-938) showed decreased expressions in stool of CC patients, which becomes more pronounced as the cancer progresses from early to late TNM stages (0-IV).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29573205,"Year":2018,"Title":"Plasma miRNA can detect colorectal cancer, but how early?","Abstract":"Colorectal cancer (CRC) is a major cause of deaths worldwide but has a good prognosis if detected early. The need for efficient, preferable non- or minimally invasive, inexpensive screening tools is therefore critical. We analyzed 12 miRNAs in pre- and postdiagnostic plasma samples to evaluate their potential as CRC screening markers. We used a unique study design with two overlapping cohorts, allowing analysis of pre- and postdiagnostic samples from 58 patients with CRC and matched healthy controls. Plasma concentrations of miR-15b, -16, -18a, -19a, 21, -22, -25, -26a, -29c, -142-5p, -150, and -192 were measured by semi-quantitative real-time PCR. Concentrations of miR-18a, -21, -22, and -25 in plasma from patients with CRC were significantly altered compared to healthy controls. Combined as a multimarker panel, they detected CRC with an AUC of 0.93. Furthermore, levels of these three miRNAs also showed different levels in the prediagnostic case samples close to diagnosis. Only miR-21-levels were elevated several years before diagnosis. Plasma levels of miR-18a, -21, -22, and -25 show promise as screening biomarkers for CRC. However, based on our unique analysis of prediagnostic and postdiagnostic samples from the same patients, we conclude that circulating miRNAs elevated at diagnosis may not automatically be suitable for CRC screening, if the increase occurs too close to clinical diagnosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29564561,"Year":2018,"Title":"Development and endoscopic appearance of colorectal tumors are characterized by the expression profiles of miRNAs.","Abstract":"Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We previously reported to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. In this report, we focused on colorectal adenoma (tubular or tubulovillous adenoma), or tubular early carcinoma or type 2 adenocarcinoma, familial adenomatous polyposis (FAP), ulcerative colitis-associated tumor (UCAT), and sessile serrated adenoma/polyp (SSA/P). We tried to clarify the relationship between the expression of the miRNAs and the colorectal tumor development. The expression levels of miR-143, -145, and -34a were reduced in most of the polypoid and FAP tumors compared with those in the flat elevated, UCAT, SSA/P ones. In type 2 adenocarcinomas, the expression profile of these miRNAs was similar to those of the polypoid and FAP tumors. The expression levels of miR-7 and -21 were up-regulated in non-granular type of laterally spreading tumor, UCAT, and SSA/P compared with those in polypoid and FAP tumors. These findings indicated that the expression of onco-related miRNAs was closely associated with the development and endoscopic appearance of colorectal tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29552756,"Year":2018,"Title":"Correlation between miR-21 and miR-145 and the incidence and prognosis of colorectal cancer.","Abstract":"PURPOSE: The purpose of this study was to investigate the expression of microRNA (miR)-21 and miR-145 in serum and tumor tissues of patients with colorectal cancer (CRC), and to explore the correlation between the expression of these miRs and the clinicopathological parameters and prognosis of CRC patients. METHODS: Serum specimens, frozen tumor tissue and adjacent normal tissue of 50 CRC patients who were hospitalized in our hospital from February 2009 to February 2011 were collected, along with serum specimens of 30 healthy people (control). The expression levels of miR-21 and miR-145 in serum, tumor tissues and adjacent normal tissues were detected by quantitative real time polymerase chain reaction (qRT-PCR). The correlation between the expression of the two miRs in serum was analyzed by Spearman method. The relationship between the expression of miR- 21 and miR-145 in serum and the pathological parameters and prognosis of patients with CRC were analyzed using clinical data. RESULTS: The expression level of miR-21 in CRC tissue was significantly higher than that in adjacent normal tissues, while the expression of miR-145 in CRC tissue was significantly lower than that in adjacent normal tissues. The expression level of miR-21 in the serum of CRC patients was significantly higher compared with healthy people, while the expression of miR-145 in the serum of CRC patients was significantly lower than that in healthy people. The expression of miR-21 and miR-145 in the serum was positively correlated with their expression in tumor tissue. High expression level of miR-21 in the serum was correlated with tumor size, grade of differentiation, invasion, metastasis and clinical stage, and low expression level of miR-145 in the serum was correlated with tumor size, grade of differentiation, invasion, metastasis and clinical stage. The 5-year overall survival (OS) was 52% (26/50). Single factor survival analysis showed that miR-21 and miR-145 were the influencing factors of OS of patients with CRC. CONCLUSIONS: High expression of miR-21 and low expression of miR-145 are closely related to the development and progression of CRC, especially with the grade of differentiation, invasion, metastasis and clinical stage. MiR-21 and miR-145 in the serum can be used as markers for early screening of CRC and indicators for prognosis prediction.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29549908,"Year":2018,"Title":"Ten-eleven translocation 1 (TET1) gene is a potential target of miR-21-5p in human colorectal cancer.","Abstract":"DNA 5-methylcytosine (5-mC) methylation, a key epigenetic mark, is critical for biological and pathological processes. Aberrant DNA methylation occurs in all tumor types and correlates with tumor suppressor gene silencing. DNA methylation is thought to be very stable, and active DNA demethylation remains a long-standing enigma. Recently, the ten-eleven translocation (TET) family of oxygenases are found to oxidize 5-mC to 5-hydroxymethylcytosine (5-hmC), which is prerequisite for active DNA demethylation. Both TET1 expression and global 5-hmC content are significantly reduced in colorectal cancer (CRC), the top leading cause of cancer-related death in the world. However, the involving molecular mechanisms are still unclear. The oncogenic microRNA (miRNA) miR-21-5p has recently identified as a diagnostic and prognostic biomarker in CRC. In this study, TET1 was predicted as a novel target of miR-21-5p by using a web-based predictive software starBase v2.0. We found that the 3'-UTR region of TET1 gene contains a miR-21-5p-binding site. Examination of tumor tissues from CRC patients found that loss of TET1 was associated with the progression of CRC to advance stages. In addition, negative correlation of miR-21-5p and TET1 expression was also observed. Transfection of the synthetic miR-21-5p mimic or inhibitor into the colorectal cancer cells could inhibit or increase the TET1-3'-UTR luciferase activity, respectively. Our results demonstrate that TET1 is a potential target of miR-21-5p in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29542167,"Year":2018,"Title":"Inhibition of microRNA-21-3p suppresses proliferation as well as invasion and induces apoptosis by targeting RNA-binding protein with multiple splicing through Smad4/extra cellular signal-regulated protein kinase signalling pathway in human colorectal cancer HCT116 cells.","Abstract":"MicroRNA-21-3p (miR-21-3p), the passenger strand of pre-mir-21, has been found to be high-expressing in various cancers and to be associated with tumour malignancy, which is proposed as a novel focus in malignant tumours. Colorectal cancer (CRC), currently known as one of the most prevalent malignancy, is a leading cause of cancer death. This study aimed to investigate the key role of miR-21-3p in CRC by inhibiting its expression using transfection with miR-21-3p inhibitors into human CRC HCT116 cells. Results showed that the expression of miR-21-3p was higher than other CRC cells used in the study including Lovo, HT29, Colo320 and SW480 cells, inhibition of which suppressed the proliferation and induced cell cycle arrest in HCT116 cells. Besides, transfection with miR-21-3p inhibitors also attenuated cell migration and invasion, and induced apoptosis as well. Moreover, luciferase assay confirmed RBPMS as a direct target of miR-21-3p in HCT116 cells. Further, miR-21-3p inhibitors increased the nuclear accumulation of Smad4 and reduced phosphorylation of ERK. Interestingly, we found that silence of RBPMS using RNA interference (siRNA) not only elevated the cell viability but also increased the phosphorylation of ERK and reversed the nuclear accumulation of Smad4 induced by miR-21-3p inhibitors in HCT116 cells. Data suggest that inhibition of miR-21-3p suppresses cell proliferation, invasion as well as migration and induces apoptosis by directly targeting RBPMS through Smad4/ERK signalling pathway in HCT116 cells. Our study demonstrates miR-21-3p as a potent target for suppressing tumour progression of CRC which may have implications in CRC therapy in the future.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29518480,"Year":2018,"Title":"Longitudinal monitoring reveals dynamic changes in circulating tumor cells (CTCs) and CTC-associated miRNAs in response to chemotherapy in metastatic colorectal cancer patients.","Abstract":"We evaluated the changes in CTC count and CTC-associated miRNAs during the course of chemotherapy in patients with metastatic colorectal cancer. Blood samples were collected from 9 metastatic colorectal cancer patients prior to chemotherapy and at every other chemotherapy session during the course of treatment. CTCs were isolated and enumerated using a size-exclusion method (CellSievo, Singapore). CTC-associated miRNAs were isolated using a paper-based, partitioning method, and analyzed using reverse transcription quantitative real-time PCR (MiRXES, Singapore). CTC count trends generally correlated with disease progression defined by radiological measurements and trends in carcinoembryonic antigen (CEA) levels; hence CTC counts may be useful in cases where CEA is not elevated. CTC-associated miRNAs identified were miR-15b, miR-16, miR-19a, miR-21, miR-25, miR-30d, miR-126, miR-185, miR-221, miR-222, and miR-324-5p. The expression of CTC-associated miRNAs did not appear to correlate with CTC count and exhibited inter-individual heterogeneity. This pilot study suggests that analysis of CTC changes during the course of treatment may be useful in monitoring response to therapy in metastatic colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29484416,"Year":2018,"Title":"Prognostic impact of sarcopenia and its correlation with circulating miR-21 in colorectal cancer patients.","Abstract":"Severe malnutrition accompanied by sarcopenia and cachexia, is strongly associated with the surgical and oncological outcomes in cancer patients. The aim of the present study was to clarify the clinical significance of sarcopenia and its correlation with sarcopenia-associated miRNA in colorectal cancer (CRC). A total of 167 CRC patients were enrolled in the present study. We evaluated psoas muscle mass index (PMI) and intramuscular adipose tissue content (IMAC). The expression of miR-21 in CRC tissues and preoperative serum was evaluated using quantitative PCR. Despite the lack of significant correlation between IMAC and disease-correlated factors, decreased PMI was significantly associated with well-established clinicopathological factors for disease progression. Decreased PMI was an independent prognostic factor for both overall survival and disease-free survival and was an independent risk factor for various types of metastasis. In contrast to the expression of tissue miR-21, the expression of serum miR-21 was significantly increased in CRC patients with low PMI. Furthermore, postoperative PMI was drastically improved compared with preoperative PMI in CRC patients with potentially curative resections. In conclusion, skeletal muscle mass may be a prognostic and predictive biomarker for distant metastasis in CRC patients and quantification of serum miR-21 expression could help clinicians make decisions regarding nutrition intervention strategies in CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29456985,"Year":2018,"Title":"Evaluation of miR-21 Inhibition and its Impact on Cancer Susceptibility Candidate 2 Long Noncoding RNA in Colorectal Cancer Cell Line.","Abstract":"Background: Both microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) have been shown to have a critical role in the regulation of cellular processes such as cell growth and apoptosis, as well as cancer progression and metastasis. lncRNAs are aberrantly expressed in many diseases including cancer. Although it is well known that miRNAs can target a large number of protein-coding genes, little is known whether miRNAs can also target lncRNAs. In the present study, we determine whether miR-21 can regulate lncRNA cancer susceptibility candidate 2 (CASC2) in colorectal cancer. Materials and Methods: LS174T cells were transfected with locked nucleic acid (LNA)-anti-miR-21 and scrambled LNA for 24, 48 and 72 h. The expression of miR-21 and lncCASC2 was evaluated by quantitative reverse transcriptase polymerase chain reaction. Results: However, contrary to what we expected and reported by others, lncCASC2 quantity was significantly reduced in LNA treated LS174T cells compared to the scrambled treated and normal untreated cells (P < 0.05). Conclusion: The interaction of miRNA and lncRNA are not as simple as suggested by other reports. Moreover, it could be complex molecular mechanisms underlying the communication of various noncoding RNA elements.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29404790,"Year":2019,"Title":"MicroRNA Expression Levels and Histopathological Features of Colorectal Cancer.","Abstract":"INTRODUCTION: Non-coding RNAs have opened a new window in cancer biology. MicroRNAs (miRNAs), as a family of non-coding RNAs, play an important role in the gene regulation. The aberrant expression of these small molecules has been documented to involve in colorectal cancer (CRC) pathogenesis. This study aimed to examine the expression of miRNAs in CRC and to correlate their expression levels with histological markers (Ki-67 and CD34). MATERIALS AND METHODS: Tumor tissues and matched normal adjacent tissues were collected from 36 patients with newly diagnosed CRC. Immunohistochemical (IHC) staining of tumor tissues was performed for Ki-67 (proliferation) and CD34 (angiogenesis) markers, and the immunoexpression staining scores were obtained. A polyadenylation SYBER Green quantitative real-time PCR technique was used to quantify the expression of a panel of five CRC-related miRNAs (hsa-miR-21, 31, 20a, 133b, and 145). Histopathological (H) scores and miRNA expression levels were correlated with clinicopathological features including the degree of differentiation, staging, and lymphovascular invasion. RESULTS: Our results showed the significant difference between the two groups for the expression level of hsa-miR-21, hsa-miR-31, hsa-miR-145, and miR-20a (P < 0.001), but not for hsa-miR-133b (P = 0.57). Further analysis revealed an inverse significant correlation between hsa-miR-145 and Ki-67 (r = - 0.942, P < 0.001). While a positive correlation was observed between hsa-miR-21 and Ki-67 (r = 0.920, P < 0.001), and hsa-miR-21 and CD34 (r = 0.981, P < 0.001). Also, a positive correlation between hsa-miR-31 and Ki-67 (r = 0.913, P < 0.001), hsa-miR-31 and CD34 (r = 0.798, P < 0.05), hsa-miR-20a and Ki-67 (r = 0.871, P < 0.001), and hsa-miR-20a and CD34 (r = 0.890, P < 0.001) was found. CONCLUSION: Dysregulation of miRNAs and correlation with molecular histopathology indicate a biological role for miRNAs in various cellular processes including cell proliferation and angiogenesis in CRC development. On the other hand, the pattern of miRNA expression and its correlation with histological markers are potentially valuable to apply as diagnostic biomarkers for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29363233,"Year":2018,"Title":"Serum microRNA signatures and metabolomics have high diagnostic value in colorectal cancer using two novel methods.","Abstract":"Recently, many new diagnostic biomarkers have been developed for colorectal cancer. We chose 2 methods with high diagnostic efficiency, the detection of serum microRNA and metabolomics based on gas chromatography/mass spectrometry (GC/MS), and aimed to establish appropriate models. We reviewed the diagnostic value of all microRNA identified by previous diagnostic tests. We selected appropriate microRNA to validate their diagnostic efficiency, and determined the optimal combination. We included 85 patients with colorectal cancer (CRC) and 78 healthy controls (HC) and detected the expression of the microRNA. GC/MS analysis was conducted, and we used 3 multivariate statistical methods to establish diagnostic models. The concentrations of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were detected for comparison with the novel models. Ultimately, 62 published studies and 63 microRNA were included in this review. MiR-21, miR-29a, miR-92a, miR-125b and miR-223 were selected to further validate their diagnostic value. The serum levels of the 5 microRNA in CRC patients were significantly higher than those in the HC. The combination of miR-21, miR-29a, miR-92a and miR-125b had the highest area under the curve (AUC) at 0.952, with a sensitivity of 84.7% and a specificity of 98.7%. The GC/MS analysis exhibited an excellent diagnostic value and the AUC reached 1.0. With regard to traditional biomarkers, the AUC of CEA and CA19-9 were 0.808 and 0.705, respectively. The application prospects are good for microRNA and metabolomics as new diagnostic methods because of their high diagnostic value compared with traditional biomarkers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29355387,"Year":2017,"Title":"Gender-dependent expression of leading and passenger strand of miR-21 and miR-16 in human colorectal cancer and adjacent colonic tissues.","Abstract":"miRNAs are small regulatory RNA molecules involved in posttranscriptional gene silencing. Their biosynthesis results in the formation of duplex consisting of a leading and a passenger strand of mature miRNA. The leading strand exhibits the main activity but recent findings indicate a certain role of the passenger strand as well. Deregulated levels of miRNA were found in many types of cancers including colorectal cancer. miR-21 and miR-16 were indicated as possible markers of colorectal cancer, however, small attention to gender differences in their expression was paid so far. Therefore, the aim of our study was to investigate the expression of miR-21-5p, miR-21-3p, miR-16-5p and miR-16-3p in human colorectal cancer tissue and compare it to the adjacent tissues taken during surgery in men and women separately. Our results showed an up-regulation of all measured miRNAs in tumor tissue compared to adjacent tissues. As expected, tumors and adjacent tissues exhibited a significantly higher expression of leading miRNAs compared to passenger strand of miR-21 and miR-16. The expression of leading and passenger strand of miR-21 and miR-16 positively correlated exhibiting the highest correlation coefficient in the distal tissue. The expression pattern showed gender-dependent differences, with higher levels of miRNA in men than in women. Our findings indicate a gender-related expression pattern of miRNA, which should be considered as an important factor in generating new prognostic or diagnostic biomarkers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29283887,"Year":2017,"Title":"Exosomal microRNAs derived from colorectal cancer-associated fibroblasts: role in driving cancer progression.","Abstract":"Colorectal cancer is a global disease with increasing incidence. Mortality is largely attributed to metastatic spread and therefore, a mechanistic dissection of the signals which influence tumor progression is needed. Cancer stroma plays a critical role in tumor proliferation, invasion and chemoresistance. Here, we sought to identify and characterize exosomal microRNAs as mediators of stromal-tumor signaling. In vitro, we demonstrated that fibroblast exosomes are transferred to colorectal cancer cells, with a resultant increase in cellular microRNA levels, impacting proliferation and chemoresistance. To probe this further, exosomal microRNAs were profiled from paired patient-derived normal and cancer-associated fibroblasts, from an ongoing prospective biomarker study. An exosomal cancer-associated fibroblast signature consisting of microRNAs 329, 181a, 199b, 382, 215 and 21 was identified. Of these, miR-21 had highest abundance and was enriched in exosomes. Orthotopic xenografts established with miR-21-overexpressing fibroblasts and CRC cells led to increased liver metastases compared to those established with control fibroblasts. Our data provide a novel stromal exosome signature in colorectal cancer, which has potential for biomarker validation. Furthermore, we confirmed the importance of stromal miR-21 in colorectal cancer progression using an orthotopic model, and propose that exosomes are a vehicle for miR-21 transfer between stromal fibroblasts and cancer cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29134398,"Year":2017,"Title":"MicroRNAs and their role for T stage determination and lymph node metastasis in early colon carcinoma.","Abstract":"Worldwide, colon cancer is among the most common cancer entities. Understanding the molecular background is the key to enable accurate stage determination, which is crucial to assess optimal therapy options. The search for preoperative biomarkers is ongoing. In recent years, several studies have proposed a diagnostic and prognostic role for miRNAs in cancer. Aim of this study was to evaluate miRNA expression patterns correlating with tumor stage, especially lymph node metastasis, in primary colon carcinoma tissue. Screening was accomplished using GeneChip((R)) miRNA v3.0 arrays (Thermo Fisher Scientific, Waltham, MA, USA) and validated via TaqMan((R)) qPCR assays (Thermo Fisher Scientific, Waltham, MA, USA) to investigate miRNA expressions in 168 FFPE and 83 fresh frozen colon carcinoma samples. Regarding lymph node status, analyses displayed no significantly differential miRNA expression. Interestingly, divergent expression of miR-18a-5p, miR-20a-5p, miR-21-5p, miR-152-3p and miR-1973 was detected in stage pT1. Although miRNAs might not represent reliable biomarkers regarding lymph node metastasis status, they could support risk assessment in stage T1 tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":29112225,"Year":2018,"Title":"Global and targeted circulating microRNA profiling of colorectal adenoma and colorectal cancer.","Abstract":"BACKGROUND: Circulating microRNAs (miRNAs) are emerging as promising biomarkers for cancer. The objective of the current study was to investigate the potential of circulating cell-free miRNAs as biomarkers for colorectal cancer (CRC) and its precursor lesion, colorectal adenoma. METHODS: The serum levels of 800 miRNAs were assessed in a discovery set of 21 patients with CRC, 19 patients with adenoma, and 21 healthy controls using the NanoString miRNA analysis platform. Significantly differentially expressed miRNAs were examined further in a validation cohort of 34 patients with CRC, 33 patients with adenoma, and 35 healthy controls using Fluidigm quantitative polymerase chain reaction assays. RESULTS: The ratios between the expression values of the differentially expressed miRNAs were computed. Three miRNA ratios (miR-17-5p/miR-135b, miR-92a-3p/miR135b, and miR-451a/miR-491-5p) were validated for discriminating patients with adenoma and those with CRC from the healthy control group, and 5 miRNA ratios (let-7b/miR-367-3p, miR-130a-3p/miR-409-3p, miR-148-3p/miR-27b, miR-148a-3p/miR-409-3p, and miR-21-5p/miR-367-3p) were validated for discriminating patients with CRC from those with adenoma and healthy controls. The area under the receiver operating characteristic curve values for the 3 miRNA ratios in discriminating patients with adenoma from healthy controls were 0.831 and 0.735, respectively, in the discovery and validation sets. The area under the receiver operating characteristic curve values for the 5 miRNA ratios in discriminating patients with CRC from those with adenoma were 0.797 and 0.732, respectively, in the discovery and validation sets. Pathway analysis revealed that target genes regulated by the miRNAs from the miRNA ratios were enriched mainly in metabolism-related and inflammation-related pathways. CONCLUSIONS: The data from the current study suggest that circulating miRNAs can distinguish patients with CRC and those with adenoma and may represent novel biomarkers for the early, noninvasive detection of CRC. Cancer 2018;124:785-96. (c) 2017 American Cancer Society.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28978119,"Year":2017,"Title":"Systematic literature review and clinical validation of circulating microRNAs as diagnostic biomarkers for colorectal cancer.","Abstract":"Because patients with colorectal cancer (CRC) are usually diagnosed at an advanced stage and current serum tumor markers have limited diagnostic efficacy, there is an urgent need to identify reliable diagnostic biomarkers. To better define the diagnostic potential of microRNAs (miRNAs) for CRC, we performed a comprehensive evaluation of reported circulating CRC miRNA markers. After a systematic literature review, we selected 30 candidate miRNAs and used quantitative real-time polymerase chain reaction to examine their expression in a training cohort of 120 plasma samples (CRC vs healthy controls (HC) = 60:60). Expression data was confirmed in a validation cohort of 160 plasma samples (CRC vs HC = 80:80). We ultimately identified 5 dysregulated circulating miRNAs (miR-15b, miR-17, miR-21, miR-26b, and miR-145), of which miR-21 and miR-26b proved to have the best diagnostic performance in the training and validation cohorts, respectively. Based on these results, we propose a novel blood-based diagnostic model, integrating 5 CRC-related miRNAs and serum carcinoembryonic antigen (CEA), which provides better diagnostic performance than the combined 5 miRNAs, CEA alone, or any single miRNA. We propose that the novel CRC diagnostic model presented here will be useful for overcoming the limitations faced by current non-invasive diagnostic strategies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28964256,"Year":2017,"Title":"A novel mechanism of lncRNA and miRNA interaction: CCAT2 regulates miR-145 expression by suppressing its maturation process in colon cancer cells.","Abstract":"BACKGROUND: Although both long and micro RNAs are emerging as important functional components in colorectal cancer (CRC) progression and metastasis, the mechanism of their interaction remains poorly understood. CCAT2 (Colon cancer-associated transcript-2), a long noncoding RNA (lncRNA), has been reported to be over-expressed in CRC and is found to promote tumor growth. miRNAs, a class of naturally occurring short RNAs negatively control the expression of target genes by cleaving mRNA or through translation repression. Recently, we reported that miR-145 and miR-21 cooperate to regulate colon cancer stem cell (CSC) proliferation and differentiation. Considering that CCAT2 is mainly located in the nucleus and miRNA maturation process begins in the nucleus, we hypothesize that CCAT2 selectively blocks miR-145 maturation process, resulting in decreased mature miR-145 affecting colon CSC proliferation and differentiation. METHODS: The levels of CCAT2 were manipulated by transfection of CCAT2 expression plasmid or knockdown by siRNA or by CRISPR/Cas9. Quantitative RT-PCR was performed to examine the expression of CCAT2 and pri-, pre- and mature miR-145/21. Fluorescence in situ hybridization (FISH) was used to visualize CCAT2 in the cells. In vitro processing of pri-miRNA-145 was performed using T7 RNA polymerase and recombinant human Dicer. RESULTS: We have observed that modulated expression of CCAT2 regulates the expression of miR-145 in colon cancer HCT-116 and HT-29 cells. Knockout of CCAT2 increases miR-145 and negatively regulates miR-21 in HCT-116 cells, impairs proliferation and differentiation. In contrast, stable up-regulation of CCAT2 decreases mature miR-145 and increases the expression of several CSC markers in colon cancer cells. We have also observed that CCAT2 is enriched in the nucleus and correlates with the expression of pre-miR-145 but not pre-miR-21 in HCT-116 cells. These results indicate CCAT2 selectively blocks miR-145 maturation by inhibiting pre-miR-145 export to cytoplasm. Further, we revealed that CCAT2 blocks cleavage of pre-miR-145 by Dicer in vitro. CONCLUSIONS: Our results identify CCAT2 as a negative regulator of miRNA-145 biogenesis, and expose a novel mechanism of lncRNA-miRNA crosstalk.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28957811,"Year":2017,"Title":"MicroRNA-21 (Mir-21) Promotes Cell Growth and Invasion by Repressing Tumor Suppressor PTEN in Colorectal Cancer.","Abstract":"BACKGROUND/AIMS: MicroRNA-21 (miR-21) has been demonstrated to play an important role in carcinogenesis; however, its mechanism of action in colorectal cancer (CRC) has not been fully elucidated. The aim of the present study was to explore the oncogenic function of miR-21 and its molecular mechanism in CRC. METHODS: A total of 105 paired tumor and tumor-adjacent normal tissue specimens from CRC patients and two CRC cell lines (HCT-116 and SW480) were studied. The protein and mRNA expression levels of PTEN and miR-21 were examined using western blot analysis and real-time reverse transcription-PCR (qRT-PCR). Furthermore, we transfected CRC cells with different combinations of ectopic-expression vector or shRNA expression vector of miR-21 and phosphatase and tensin homolog (PTEN) to modulate the expression levels of miR-21 and PTEN respectively, and then analyzed the phenotypic alterations of CRC cells. Tumorigenesis was also evaluated by xenografting HCT-116 cells into nude mice. RESULTS: In this study, we showed that miR-21 expression was significantly up-regulated in CRC compared to that in normal tissues. Patients with advanced Tumor-Node-Metastasis (TNM) stage, lymph node metastasis, local invasion and higher serum carcinoembryonic antigen (CEA) levels displayed significantly high expression of miR-21. The PTEN protein level in CRC tissues and cells was inversely correlated with miR-21 expression. Furthermore, the transfection of CRC cells with pre-miR-21 could inhibit apoptosis and promote cellular proliferation, invasion, cell cycle progression and growth of xenografts in nude mice, whereas the transfection of miR-21-specific shRNA resulted in the opposite phenomena. In addition, silencing or elevating PTEN protein could partially reverse the effect of miR-21-specific shRNA or pre-miR-21 on apoptosis, cell cycle distribution, and invasion of CRC cells. Moreover, over-expression or knockdown of miR-21 altered the protein expression of PTEN and phosphorylated Akt (p-AKT). CONCLUSION: miR-21 can modulate the malignant phenotypes such as proliferation, anti-apoptosis, cell cycle progression and invasion of CRC cells by down-regulating PTEN protein expression. The results of study might improve our understanding of the regulatory mechanism of miR-21 and provide useful targets and approaches for the clinical diagnosis and therapy of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28954383,"Year":2017,"Title":"Long non-coding RNA CASC7 inhibits the proliferation and migration of colon cancer cells via inhibiting microRNA-21.","Abstract":"Recent evidences highlight the crucial regulatory roles of long noncoding RNAs (lncRNA) in tumor biology. LncRNA CASC7 is a approximately 9.3kb lncRNA whose function is currently unknown. The present study aimed to investigate the expression of CASC7 in patients with colorectal cancer (CRC) and its effect on CRC cells. The expression levels of CASC7, miR-21 and ING3 were estimated by reverse transcription-quantitative polymerase chain reaction (RT-PCR) or western blot in CRC tissues and CRC cell lines (SW480 and HCT-116). The relationship between miR-21 and CASC7 or ING3 was analyzed by RNA immunoprecipitation (RIP), RNA pull-down and luciferase reporter assay. In addition, the biological roles of CASC7 were examined using cell counting kit-8 assay, flow cytometry, and migration and invasion assays following the downregulation or upregulation of CASC7 by small interfering RNA or pcDNA-CASC7, respectively. In this study, CASC7 expression was significantly decreased in CRC tissues and CRC cell lines. Further functional experiments suggested that CASC7 overexpression could inhibit cell viability, migration and invasion, and promote apoptosis in CRC cells. CASC7 and ING3 were both a target of miR-21 in CRC cells, and CASC7 could control ING3 expression by regulating miR-21. Moreover, we have found that CASC7 inhibited colon cancer cell proliferation and migration via miR-21/ING3 axis. These observations suggested that CASC7 played an important role in CRC pathogenesis and may be considered as a novel diagnostic marker of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28821160,"Year":2017,"Title":"Leuconostoc mesenteroides-derived anticancer pharmaceuticals hinder inflammation and cell survival in colon cancer cells by modulating NF-kappaB/AKT/PTEN/MAPK pathways.","Abstract":"Promising results from different studies on the effect of probiotics in cancer prevention and therapy have so far been reported. However, the molecular mechanism of the interaction of probiotics with cancer cells is yet to be fully understood. In the present study, Leuconostoc mesenteroides was isolated from traditional dairy products, and its probiotic characteristics were determined. HT-29 cells were treated with conditioned-medium of designated bacteria and the cell apoptosis was studied at cellular and molecular level using DAPI staining, flow cytometry, DNA ladder assays, and real-time quantitative-PCR (q-PCR). Based on our findings, L. mesenteroides promoted apoptosis in colon cancer cell line by upregulation of MAPK1, Bax, and caspase 3, and downregulation of AKT, NF-kappaB, Bcl-XL expressions and some key oncomicroRNAs such as miRNA-21 and miRNA-200b significantly (p<\/=0.03). The results indicated the likelihood of the examined probiotic as an alternative or complementary treatment modality in signaling-targeted cancer therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28734015,"Year":2017,"Title":"Different miR-21-3p isoforms and their different features in colorectal cancer.","Abstract":"MiR-21, the only microRNA (miRNA) found to be overexpressed in any type of solid tumor, its guide stand, miR-21-5p, has been studied a lot in colorectal cancer (CRC); however, few researchers focused on its passenger strand, miR-21-3p. In our study, based on The Cancer Genome Atlas (TCGA) data, we found that there were more varieties and quantities of miR-21-3p isoforms in microsatellite instability (MSI)-type CRC. We further examined the role of miR-21-3p by in vitro and in vivo studies. MiR-21-3p may be an oncogene in CRC by promoting cellular mobility through epithelial-mesenchymal transition. However, different isoforms, especially miR-21-3p 0 | 2, may be a favorable prognostic marker for CRC survival, probably due to increased complementary effect of miR-21-5p and/or target genes. Further study investigating the underlying mechanism of miRNA isoforms is needed.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28693154,"Year":2017,"Title":"Association between the expression of microRNAs and the response of patients with locally advanced rectal cancer to preoperative chemoradiotherapy.","Abstract":"Preoperative chemoradiotherapy (CRT) followed by mesorectal excision is the standard treatment for patients with locally advanced rectal cancer (LARC). The balance between treatment efficacy and toxicity is a major issue in the clinical management of these patients. There is a requirement for the identification of predictive molecular biomarkers for the response of patients to CRT. The present study aimed to analyze the association between microRNA (miRNA/miR) expression and treatment efficacy in patients with LARC who were treated with preoperative CRT. From previous clinical trials, 55 patients for the test cohort and 130 patients for the validation cohort met the criteria for the present investigation. Through reverse transcription-quantitative polymerase chain reaction analysis, the expression of miR-21, -31, -125b, -145 and -630 in the diagnostic biopsies was analyzed. The primary endpoint of tumor regression was evaluated according to Mandard's Tumor Regression Grade (TRG) system. In the test cohort, a significant association was identified between low miRNA-145 expression and TRG1+2 (P=0.0003). Similarly, this association was identified in the validation cohort, although it did not reach statistical significance. Furthermore, a significant association between high miRNA-21 expression and TRG1+2 (P=0.035) was observed in the validation cohort. The remaining miRNAs analyzed were not associated with TRG. The results of the present study highlight the clinical importance of miRNAs in LARC and underline the necessity for validation studies in this setting.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28690395,"Year":2017,"Title":"An Assessment of Database-Validated microRNA Target Genes in Normal Colonic Mucosa: Implications for Pathway Analysis.","Abstract":"BACKGROUND: Determination of functional pathways regulated by microRNAs (miRNAs), while an essential step in developing therapeutics, is challenging. Some miRNAs have been studied extensively; others have limited information. In this study, we focus on 254 miRNAs previously identified as being associated with colorectal cancer and their database-identified validated target genes. METHODS: We use RNA-Seq data to evaluate messenger RNA (mRNA) expression for 157 subjects who also had miRNA expression data. In the replication phase of the study, we replicated associations between 254 miRNAs associated with colorectal cancer and mRNA expression of database-identified target genes in normal colonic mucosa. In the discovery phase of the study, we evaluated expression of 18 miR-NAs (those with 20 or fewer database-identified target genes along with miR-21-5p, miR-215-5p, and miR-124-3p which have more than 500 database-identified target genes) with expression of 17 434 mRNAs to identify new targets in colon tissue. Seed region matches between miRNA and newly identified targeted mRNA were used to help determine direct miRNA-mRNA associations. RESULTS: From the replication of the 121 miRNAs that had at least 1 database-identified target gene using mRNA expression methods, 97.9% were expressed in normal colonic mucosa. Of the 8622 target miRNA-mRNA associations identified in the database, 2658 (30.2%) were associated with gene expression in normal colonic mucosa after adjusting for multiple comparisons. Of the 133 miRNAs with database-identified target genes by non-mRNA expression methods, 97.2% were expressed in normal colonic mucosa. After adjustment for multiple comparisons, 2416 miRNA-mRNA associations remained significant (19.8%). Results from the discovery phase based on detailed examination of 18 miRNAs identified more than 80 000 miRNA-mRNA associations that had not previously linked to the miRNA. Of these miRNA-mRNA associations, 15.6% and 14.8% had seed matches for CRCh38 and CRCh37, respectively. CONCLUSIONS: Our data suggest that miRNA target gene databases are incomplete; pathways derived from these databases have similar deficiencies. Although we know a lot about several miRNAs, little is known about other miRNAs in terms of their targeted genes. We encourage others to use their data to continue to further identify and validate miRNA-targeted genes.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28560697,"Year":2017,"Title":"The Cardiotoxic Mechanism of Doxorubicin (DOX) and Pegylated Liposomal DOX in Mice Bearing C-26 Colon Carcinoma: a Study Focused on microRNA Role for Toxicity Assessment of New Formulations.","Abstract":"PURPOSE: MicroRNAs (miRs) are a group of small non-coding RNAs that regulate transcriptional or post-transcriptional gene expression. The aim of the present study was to investigate the role of miR -1, -21 and -145 and their targets in cardiotoxicity-induced by DOX and pegylated liposomal DOX. METHODS: BALB/c mice subjected to subcutaneous injection of C-26 tumor cells. Eight days after tumor inoculation, animals were divided into 6 groups: control, liposome, DOX (6 and 9 mg/kg) and PL-DOX (6 and 9 mg/kg). The formulations were administered one time per week for four weeks. 24 h after the last injection, mice were sacrificed; blood and heart samples were taken. Western blot analysis was done on protein extracts to investigate the expression of cardiac caspase-3, -8, Bax, Bcl2, Programmed cell death 4 (PDCD4) and BCL2/Adenovirus E1B 19 kDa Interacting Protein 3 (BNIP3). The expression levels of miR -1, -21 and -145 were also evaluated by quantitative real-time PCR. RESULTS: Mice treated with both DOX formulations showed a marked inhibition in tumor growth. Western blot analysis indicated that the expression level of cardiac caspase-3, caspase-8, Bax and BNIP3 were up-regulated due to DOX injection (9 mg/kg). Exposure of mice with DOX resulted in a significant increase in cardiac miR-1 and miR-21 expression level. PL-DOX treatment did not change the proteins and miRs expression. CONCLUSION: The results suggest that miR -1, -21 and -145 may involve in cardiotoxicity induced by DOX. Evaluation of miRs signaling pathways might be of potential value for toxicity assessment of new formulations. Graphical Abstract The cardiotoxic mechanism of doxorubicin (DOX) and pegylated liposomal DOX (PL-DOX).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28418912,"Year":2017,"Title":"Human microRNA expression in sporadic and FAP-associated desmoid tumors and correlation with beta-catenin mutations.","Abstract":"Desmoid tumors (DT) are rare, benign, fibroblastic neoplasm with challenging histological diagnosis. DTs can occur sporadically or associated with the familial adenomatous polyposis coli (FAP). Most sporadic DTs are associated with beta-catenin gene (CTNNB1) mutations, while mutated APC gene causes FAP disease. microRNAs (miRNAs) are involved in many human carcinogenesis.The miRNA profile was analyzed by microarray in formalin-fixed, paraffin-embedded (FFPE) specimens of 12 patients (8 sporadic, 4 FAP-associated) and 4 healthy controls. One hundred and one mRNAs resulted dysregulated, of which 98 in sporadic DTs and 8 in FAP-associated DTs, 5 were shared by both tumors. Twenty-six miRNAs were then validated by RT-qPCR in 23 sporadic and 7 FAP-associated DT samples matched with healthy controls. The qPCR method was also used to evaluate the CTNNB1 mutational status in sporadic DTs. The correlation between sporadic DTs and miRNA expression showed that miR-21-3p increased in mutated versus wild-type DTs, while miR-197-3p was decreased. The mRNA expression of Tetraspanin3 and Serpin family A member 3, as miR-21-3p targets, and L1 Cell Adhesion Molecule, as miR-197-3p target, was also evaluate. CTNNB1 mutations associated to miRNA dysregulation could affect the genesis and the progression of this disease and help histological diagnosis of sporadic DTs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28376502,"Year":2017,"Title":"Circulating Exosomal MicroRNA-21 as a Biomarker in Each Tumor Stage of Colorectal Cancer.","Abstract":"OBJECTIVE: We clarified the predictive and prognostic value of circulating plasma exosomal microRNA-21 (miR-21) in each TNM stage of colorectal cancer (CRC) patients. METHODS: The microRNA (miRNA) profiles of the plasma exosomes, primary tumor tissues, and liver metastasis tissues from the same CRC patients were examined using a microarray. For validation analysis, the plasma exosome samples from 326 CRC patients were measured by TaqMan miRNA assays. RESULTS: In the miRNA microarray analyses, miR-21 showed the highest upregulation in exosomes, primary tumor tissues, and liver metastasis tissues. Significant correlations were demonstrated between exosomal miR-21 and tissue miR-21 levels. As for the relationship to the pathological condition, exosomal miR-21 showed a significant association with liver metastasis and TNM stage. The overall survival (OS) rates and disease-free survival (DFS) rates in high-exosomal-miR-21 patients were significantly worse than those in low-miR-21 patients. Exosomal miR-21 levels were an independent prognostic factor for OS and DFS in CRC patients with TNM stage II or III, and for OS in patients with TNM stage IV. CONCLUSION: Plasma exosomal miR-21 levels are a useful biomarker for the prediction of recurrence and poor prognosis in CRC patients with TNM stage II, III, or IV.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28347230,"Year":2017,"Title":"Inhibition of microRNA-21 via locked nucleic acid-anti-miR suppressed metastatic features of colorectal cancer cells through modulation of programmed cell death 4.","Abstract":"Colorectal cancer is among the most lethal of malignancies, due to its propensity to metastatic spread and multifactorial-chemoresistance. The latter property supports the need to identify novel therapeutic approaches for the treatment of colorectal cancer. MicroRNAs are endogenous non-coding small RNA molecules that function as post-transcriptional regulators of gene expression. Recently, programmed cell death 4 has been identified as a protein that increases during apoptosis. This gene is among the potential targets of miR-21 (OncomiR). Locked nucleic acid-modified oligonucleotides have recently emerged as a potential therapeutic option for targeting microRNAs. The aim of this study was to explore the functional role of locked nucleic acid-anti-miR-21 in the LS174T cell line in vitro and in vivo models. LS174T cells were treated with locked nucleic acid-anti-miR-21 for 24, 48, and 72 h in vitro. The expression of miR-21 and PDCD4 at messenger RNA (mRNA) level was evaluated by quantitative real-time polymerase chain reaction, while the protein level of PDCD4 was determined by Western blotting. Cell migratory behavior and the cluster-forming ability of cells were assessed before and after therapy. The disseminated tumor cells were assessed in the chick chorioallantoic membrane model by Alu quantitative polymerase chain reaction. Locked nucleic acid-anti-miR-21 was transfected successfully into the LS174T cells and inhibited the expression of miR-21. Locked nucleic acid-anti-miR-21 inhibited the migration and the number of cells forming clusters. Moreover, we found that locked nucleic acid-anti-miR-21 transfection was associated with a significant reduction in metastatic properties as assessed by the in ovo model. Our findings demonstrated the novel therapeutic potential of locked nucleic acid-anti-miR-21 in colon adenocarcinoma with high miR-21 expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28289824,"Year":2017,"Title":"A miRNA signature for an environmental heterocyclic amine defined by a multi-organ carcinogenicity bioassay in the rat.","Abstract":"Heterocyclic amines (HCAs) produced during high-temperature cooking have been studied extensively in terms of their genotoxic/genetic effects, but recent work has implicated epigenetic mechanisms involving non-coding RNAs. Colon tumors induced in the rat by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) have altered microRNA (miRNA) signatures linked to dysregulated pluripotency factors, such as c-Myc and Kruppel-like factor 4 (KLF4). We tested the hypothesis that dysregulated miRNAs from PhIP-induced colon tumors would provide a \"PhIP signature\" for use in other target organs obtained from a 1-year carcinogenicity bioassay in the rat. Downstream targets that were corroborated in the rat were then investigated in human cancer datasets. The results confirmed that multiple let-7 family members were downregulated in PhIP-induced skin, colon, lung, small intestine, and Zymbal's gland tumors, and were associated with c-myc and Hmga2 upregulation. PhIP signature miRNAs with the profile mir-21(high)/mir-126(low)/mir-29c(low)/mir-215(low)/mir-145(low) were linked to reduced Klf4 levels in rat tumors, and in human pan-cancer and colorectal cancer. It remains to be determined whether this PhIP signature has predictive value, given that more than 20 different genotoxic HCAs are present in the human diet, plus other agents that likely induce or repress many of the same miRNAs. Future studies should define more precisely the miRNA signatures of other HCAs, and their possible value for human risk assessment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28236743,"Year":2017,"Title":"Direct binding of microRNA-21 pre-element with Regorafenib: An alternative mechanism for anti-colorectal cancer chemotherapy?","Abstract":"The Regorafenib is a broad-spectrum kinase inhibitor that has been approved to treat colorectal cancer (CRC). However, evidences have shown that the agent is also implicated in drug interaction with microRNA-21 (miR-21), an oncogenic miRNA which plays a key role in resisting programmed cell death in CRC cells. Here, we supposed that, instead of kinase inhibition, Regorafenib can directly bind to and then stabilize miR-21 pre-element, thus preventing RNase Dicer-meditated cleavage of the pre-element to mature miR-21. In order to verify the notion, an in silico-in vitro integrated investigation of the direct intermolecular interaction between Regorafenib and miR-21 pre-element was performed by using active pocket identification, RNA-ligand docking, molecular dynamics (MD) simulation, binding energetic analysis, and fluorescence-based assay. It was revealed that the Regorafenib can bind at the major groove-like stem region of miR-21 pre-element through three geometrically satisfactory hydrogen bonds (H-bonds) as well as a number of hydrophobic forces and pi-pi stacking, conferring strong specificity and high stability to the RNA-ligand complex system (Kd=0.73muM). Separate inversion mutation of two base pairs (G6C, C12G) and (A13U, U4A) that are involved in the H-bonding can considerably impair the affinity of Regorafenib to miR-21 pre-element, with Kd increase to 27 and 96muM, respectively. All these supported that Regorafenib can directly bind to miR-21 pre-element at molecular level and the binding mode can be properly modeled by using the proposed integrated strategy. This study would provide a potential, alternative mechanism for anti-colorectal cancer chemotherapy with Regorafenib.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28207045,"Year":2017,"Title":"Remodelling of microRNAs in colorectal cancer by hypoxia alters metabolism profiles and 5-fluorouracil resistance.","Abstract":"Solid tumours have oxygen gradients and areas of near and almost total anoxia. Hypoxia reduces sensitivity to 5-fluorouracil (5-FU)-chemotherapy for colorectal cancer (CRC). MicroRNAs (miRNAs) are hypoxia sensors and were altered consistently in six CRC cell lines (colon cancer: DLD-1, HCT116 and HT29; rectal cancer: HT55, SW837 and VACO4S) maintained in hypoxia (1 and 0.2% oxygen) compared with normoxia (20.9%). CRC cell lines also showed altered amino acid metabolism in hypoxia and hypoxia-responsive miRNAs were predicted to target genes in four metabolism pathways: beta-alanine; valine, leucine, iso-leucine; aminoacyl-tRNA; and alanine, aspartate, glutamate. MiR-210 was increased in hypoxic areas of CRC tissues and hypoxia-responsive miR-21 and miR-30d, but not miR-210, were significantly increased in 5-FU resistant CRCs. Treatment with miR-21 and miR-30d antagonists sensitized hypoxic CRC cells to 5-FU. Our data highlight the complexity and tumour heterogeneity caused by hypoxia. MiR-210 as a hypoxic biomarker, and the targeting of miR-21 and miR-30d and/or the amino acid metabolism pathways may offer translational opportunities.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28192117,"Year":2017,"Title":"NR2F2 inhibits Smad7 expression and promotes TGF-beta-dependent epithelial-mesenchymal transition of CRC via transactivation of miR-21.","Abstract":"Metastasis is one of the most decisive factors influencing CRC patient prognosis and current studies suggest that a molecular mechanism known as EMT broadly regulates cancer metastasis. NR2F2 is a key molecule in the development of CRC, but the roles and underlying mechanisms of NR2F2 in TGF-beta induced EMT in CRC remain largely unknown. In the current study, we were interested to examine the role of NR2F2 in the TGF-beta-induced EMT in CRC. Here, we found NR2F2 was upregulated in CRC cells and promotes TGF-beta-induced EMT in CRC. Using comparative miRNA profiling TGF-beta pre-treated CRC cells in which NR2F2 had been knocked down with that of control cells, we identified miR-21 as a commonly downregulated miRNA in HT29 cells treated with TGF-beta and NR2F2 siRNA, and its downregulation inhibiting migration and invasion of CRC cells. Moreover, we found NR2F2 could transcriptional activated miR-21 expression by binding to miR-21 promoter in HT29 by ChIP and luciferase assay. In the last, our data demonstrated that Smad7 was the direct target of miR-21 in CRC cells. Thus, NR2F2 could promote TGF-beta-induced EMT and inhibit Smad7 expression via transactivation of miR-21, and NR2F2 may be a new common therapeutic target for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28177881,"Year":2017,"Title":"A panel of microRNA signature in serum for colorectal cancer diagnosis.","Abstract":"Dysregulated expression of specific microRNAs (miRNAs) in serum has been recognised as promising diagnostic biomarkers for colorectal cancer (CRC). In the initial screening phase, a total of 32 differentially expressed miRNAs were selected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) based Exiqon panel with 3 CRC pool samples and 1 normal control (NC) pool. Using qRT-PCR, selected serum miRNAs were further confirmed in training (30 CRC VS. 30 NCs) and testing stages (136 CRC VS. 90 NCs). We identified that serum levels of miR-19a-3p, miR-21-5p and miR-425-5p were significantly higher in patients with CRC than in NCs. The areas under the receiver operating characteristic (ROC) curve of the three-miRNA panel were 0.86, 0.74 and 0.87 for the training, testing and the external validation stages (30 CRC VS. 18 NCs), respectively. Significantly, elevated expression of the three miRNAs was also observed in CRC tissues (n = 24). Furthermore, the expression levels of the three miRNAs were significantly elevated in exosomes from CRC serum samples (n = 10). In conclusion, we identified a serum three-miRNA panel for the diagnosis of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28176652,"Year":2018,"Title":"Mechanisms for the Inhibition of Colon Cancer Cells by Sulforaphane through Epigenetic Modulation of MicroRNA-21 and Human Telomerase Reverse Transcriptase (hTERT) Down-regulation.","Abstract":"BACKGROUND: Epigenetic modulations such as histone modifications are becoming increasingly valued for their ability to modify genes without altering the DNA sequence. Many bioactive compounds have been shown to alter genetic and epigenetic profiles in various cancers. Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables such as kale, cabbage and broccoli sprouts, is one of the most potent histone deacetylase inhibitors (HDACis) to date. Recently, it has been identified that HDACis may play a vital role in regulating microRNAs (miRs) and human telomerase reverse transcriptase (hTERT). OBJECTIVE: The aim of our study was to identify if aberrant HDAC, hTERT and miR levels could be regulated through novel dietary-based approaches in colorectal cancer (CRC) cells. METHODS: We evaluated the in vitro epigenetic effects of SFN on CRC cells by MTT assay, cellular density assay, real-time reverse transcriptase-polymerase chain reaction (RT-PCR), cell cycle analysis, western-blot assay, HDAC activity assay and teloTAGGG telomerase PCR Elisa assay. RESULTS: We demonstrated the inhibitory effects of physiologically relevant concentrations of SFN in both HCT116 and RKO CRC cells, and showed for the first time that SFN treatment decreased cell density, significantly inhibited cell viability and induced apoptosis in CRC cells. We also found that practical doses of SFN significantly down-regulated oncogenic miR-21, HDAC and hTERT mRNA, protein and enzymatic levels in CRC cells. CONCLUSION: Our studies suggest that the regulation of HDAC, hTERT and miR-21 is a promising approach for delaying and/or preventing CRC and may be accomplished via the consumption of SFN in cruciferous vegetables.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":28035913,"Year":2017,"Title":"MicroRNA-137 chemosensitizes colon cancer cells to the chemotherapeutic drug oxaliplatin (OXA) by targeting YBX1.","Abstract":"The mechanisms underlying oxaliplatin (OXA) resistance in colon cancer cells are not fully understood. MicroRNAs (miRNAs) play important roles in tumorigenesis and drug resistance. However, the relationship between miRNA and OXA resistance in colon cancer cells has not been previously explored. In this study, we utilized microRNA microarray analysis and real-time PCR to verify that miR-93, miR-191, miR-137, miR-181 and miR-491-3p were significantly down-regulated and that miR-96, miR-21, miR-22, miR-15b and miR-92 were up-regulated in both HCT-15/OXA and SW480/OXA cell lines. Blocking miR-137 caused a significant inhibition of OXA-induced cytotoxicity, therefore, miR-137 was chosen for further research. An in vitro cell viability assay showed that knockdown of miR-137 in HCT-15 and SW480 cells caused a marked inhibition of OXA-induced cytotoxicity. Moreover, we found that miR-137 was involved in repression of YBX1 expression through targeting its 3'-untranslated region. Furthermore, down-regulation of miR-137 conferred OXA resistance in parental cells, while over-expression of miR-137 sensitized resistant cells to OXA, which was partly rescued by YBX1 siRNA. The results of this study may aid the development of therapeutic strategies to overcome colon cancer cell resistance to OXA.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27982722,"Year":2017,"Title":"TargetLink, a new method for identifying the endogenous target set of a specific microRNA in intact living cells.","Abstract":"MicroRNAs are small non-coding RNAs acting as posttranscriptional repressors of gene expression. Identifying mRNA targets of a given miRNA remains an outstanding challenge in the field. We have developed a new experimental approach, TargetLink, that applied locked nucleic acid (LNA) as the affinity probe to enrich target genes of a specific microRNA in intact cells. TargetLink also consists a rigorous and systematic data analysis pipeline to identify target genes by comparing LNA-enriched sequences between experimental and control samples. Using miR-21 as a test microRNA, we identified 12 target genes of miR-21 in a human colorectal cancer cell by this approach. The majority of the identified targets interacted with miR-21 via imperfect seed pairing. Target validation confirmed that miR-21 repressed the expression of the identified targets. The cellular abundance of the identified miR-21 target transcripts varied over a wide range, with some targets expressed at a rather low level, confirming that both abundant and rare transcripts are susceptible to regulation by microRNAs, and that TargetLink is an efficient approach for identifying the target set of a specific microRNA in intact cells. C20orf111, one of the novel targets identified by TargetLink, was found to reside in the nuclear speckle and to be reliably repressed by miR-21 through the interaction at its coding sequence.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27910062,"Year":2017,"Title":"Plasma and saliva miR-21 expression in colorectal cancer patients.","Abstract":"MicroRNA-21 (miR-21) expression was quantified by real-time qRT-PCR in peripheral blood and saliva samples obtained from patients diagnosed with colorectal cancer (CRC) of varying degrees of malignancy and healthy volunteers. All patients had adenocarcinoma located in the distal colon at different stages. Significant differences were detected between the control group and the total experimental group of CRC patients (plasma, P = 0.0001; saliva, P = 5e-12). MiR-21 expression was also significantly different in certain subgroups of patients with CRC disease stages II-IV as compared to the control group. No correlation of miR-21 expression was found with regard to gender and age of patents. Also, there were no significant individual correlations and linear regression of miR-21 expression in the plasma and saliva. The estimated diagnostic sensitivity and specificity of miR-21 expression were respectively 65 and 85% in the plasma, and 97 and 91% in the saliva. Our data suggest that miR-21 in both the saliva and plasma could be a proper biomarker for CRC screening, although the saliva miR-21 expression test looks preferable due to its higher sensitivity, specificity, and technical simplicity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27876571,"Year":2017,"Title":"Fusobacterium nucleatum Increases Proliferation of Colorectal Cancer Cells and Tumor Development in Mice by Activating Toll-Like Receptor 4 Signaling to Nuclear Factor-kappaB, and Up-regulating Expression of MicroRNA-21.","Abstract":"BACKGROUND & AIMS: Nearly 20% of the global cancer burden can be linked to infectious agents. Fusobacterium nucleatum promotes tumor formation by epithelial cells via unclear mechanisms. We aimed to identify microRNAs (miRNAs) induced by F nucleatum and evaluate their ability to promote colorectal carcinogenesis in mice. METHODS: Colorectal cancer (CRC) cell lines were incubated with F nucleatum or control reagents and analyzed in proliferation and would healing assays. HCT116, HT29, LoVo, and SW480 CRC cell lines were incubated with F nucleatum or phosphate-buffered saline (PBS [control]) and analyzed for miRNA expression patterns and in chromatin immunoprecipitation assays. Cells were incubated with miRNAs mimics, control sequences, or small interfering RNAs; expression of reporter constructs was measured in luciferase assays. CRC cells were incubated with F nucleatum or PBS and injected into BALB/C nude mice; growth of xenograft tumors was measured. C57BL adenomatous polyposis coli(min/+), C57BL miR21a(-/-), and C57BL mice with full-length miR21a (controls) were given F nucleatum by gavage; some mice were given azoxymethane and dextran sodium sulfate to induce colitis and colon tumors. Intestinal tissues were collected and tumors were counted. Serum samples from mice were analyzed for cytokine levels by enzyme-linked immunosorbent assay. We performed in situ hybridization analyses to detect enrichment of F nucleatum in CRC cells. Fusobacterium nucleatum DNA in 90 tumor and matched nontumor tissues from patients in China were explored for the expression correlation analysis; levels in 125 tumor tissues from patients in Japan were compared with their survival times. RESULTS: Fusobacterium nucleatum increased proliferation and invasive activities of CRC cell lines compared with control cells. CRC cell lines infected with F nucleatum formed larger tumors, more rapidly, in nude mice than uninfected cells. Adenomatous polyposis coli(min/+) mice gavaged with F nucleatum developed significantly more colorectal tumors than mice given PBS and had shorter survival times. We found several inflammatory factors to be significantly increased in serum from mice given F nucleatum (interleukin 17F, interleukin 21, and interleukin 22, and MIP3A). We found 50 miRNAs to be significantly up-regulated and 52 miRNAs to be significantly down-regulated in CRCs incubated with F nucleatum vs PBS; levels of miR21 increased by the greatest amount (>4-fold). Inhibitors of miR21 prevented F nucleatum from inducing cell proliferation and invasion in culture. miR21a(-/-) mice had a later appearance of fecal blood and diarrhea after administration of azoxymethane and dextran sodium sulfate, and had longer survival times compared with control mice. The colorectum of miR21a(-/-) mice had fewer tumors, of smaller size, and the miR21a(-/-) mice survived longer than control mice. We found RASA1, which encodes an RAS GTPase, to be one of the target genes consistently down-regulated in cells that overexpressed miR21 and up-regulated in cells exposed to miR21 inhibitors. Infection of cells with F nucleatum increased expression of miR21 by activating Toll-like receptor 4 signaling to MYD88, leading to activation of the nuclear factor-kappaB. Levels of F nucleatum DNA and miR21 were increased in tumor tissues (and even more so in advanced tumor tissues) compared with non-tumor colon tissues from patients. Patients whose tumors had high amounts of F nucleatum DNA and miR21 had shorter survival times than patients whose tumors had lower amounts. CONCLUSIONS: We found infection of CRC cells with F nucleatum to increase their proliferation, invasive activity, and ability to form xenograft tumors in mice. Fusobacterium nucleatum activates Toll-like receptor 4 signaling to MYD88, leading to activation of the nuclear factor-kappaB and increased expression of miR21; this miRNA reduces levels of the RAS GTPase RASA1. Patients with both high amount of tissue F nucleatum DNA and miR21 demonstrated a higher risk for poor outcomes.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27798914,"Year":2016,"Title":"miR-21, miR-221 and miR-150 Are Deregulated in Peripheral Blood of Patients with Colorectal Cancer.","Abstract":"The Aim of this study was to evaluate the expression levels of miR-21, miR-221, miR-150, let-7a and miR-126a in peripheral blood of 71 patients with colorectal cancer and 80 matched healthy control individuals. We determined expression levels of these microRNAs in peripheral blood samples and used small nucleolar RNA (RNU48) as an internal control. Expression levels of miR-21 (p<0.0001) and miR-221 (p<0.0001) were significantly higher, whereas expression levels of miR-150 (p=0.0054) were significantly lower in the blood samples of patients with colorectal cancer in comparison to the control group. The combination of these three microRNAs enabled us to distinguish patients with colorectal cancer from healthy donors with a sensitivity of 80% and specificity of 74% (p<0.0001). We did not observe any correlation of the studied microRNAs with clinicopathological features of colorectal cancer, indicating that expression of these microRNAs is more likely related to the host response to the tumour than the tumour itself.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27798874,"Year":2016,"Title":"Prognostic Significance of MicroRNA-21 Expression in Patients with Unresectable Metastatic Colon Cancer.","Abstract":"BACKGROUND/AIM: MicroRNA (miR)-21 is overexpressed in most solid tumors and a high expression of miR-21 in tumor tissue is associated with a poor clinical outcome. The aim of this study was to clarify the association between the miR-21 expression in the tumor and the chemotherapeutic outcomes and survival for unresectable metastatic colon cancer (CC). MATERIALS AND METHODS: Formalin-fixed, paraffin-embedded (FFPE) samples of primary tumor were obtained from 32 patients who underwent primary tumor resection and received palliative chemotherapy for unresectable metastatic CC. MiR-21 was extracted from the FFPE and the expression of miR-21 was evaluated using quantitative real time-polymerase chain reaction (RT-PCR). The expression of miR-21 was calculated with 2-DeltaDeltaCT. RESULTS: A high miR-21 expression was associated with reduced progression-free survival (PFS) (p=0.0109) and tended to reduce overall survival (OS) (p=0.0675). CONCLUSION: miR-21 expression might be a useful prognostic marker for chemotherapeutic outcome and survival in patients with unresectable metastatic CC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27775664,"Year":2016,"Title":"A Comprehensive MicroRNA Expression Profile of Liver and Lung Metastases of Colorectal Cancer with Their Corresponding Host Tissue and Its Prognostic Impact on Survival.","Abstract":"MicroRNAs are small non-coding RNAs with a length of 18-25 nucleotides. They can regulate tumor invasion and metastasis by changing the expression and translation of their target mRNAs. Their expression is substantially altered in colorectal cancer cells as well as in the adjacent tumor-associated stroma. Both of these compartments have a mutual influence on tumor progression. In the development of metastases, cancer cells initially interact with the host tissue. Therefore, compartment-specific expression signatures of these three locations-tumor, associated stroma, and host tissue-can provide new insights into the complex tumor biology of colorectal cancer. Frozen tissue samples of colorectal liver (n = 25) and lung metastases (n = 24) were laser microdissected to separate tumor cells and the adjacent tumor-associated stroma cells. Additionally, normal lung and liver tissue was collected from the same patients. We performed a microarray analysis in four randomly selected liver metastases and four randomly selected lung metastases, analyzing a total of 939 human miRNAs. miRNAs with a significant change >2-fold between the tumor, tumor stroma, and host tissue were analyzed in all samples using RT-qPCR (11 miRNAs) and correlated with the clinical data. We found a differential expression of several miRNAs between the tumor, the tumor-associated stroma, and the host tissue compartment. When comparing liver and lung metastases, miR-194 showed a 1.5-fold; miR-125, miR-127, and miR-192 showed a 2.5-fold; miR-19 and miR-215 a 3-fold; miR-145, miR-199-3, and miR-429 a 5-fold; miR-21 a 7-fold; and, finally, miR-199-5 a 12.5-fold downregulation in liver metastases compared to lung metastases. Furthermore miR-19, miR-125, miR-127, miR-192, miR-194, miR-199-5, and miR-215 showed a significant upregulation in the normal liver tissue compared to the normal lung tissue. Univariate analysis identified an association of poor survival with the expression of miR-125 (p = 0.05), miR-127 (p = 0.001), miR-145 (p = 0.005), miR-192 (p = 0.015), miR-194 (0.003), miR-199-5 (p = 0.008), miR-215 (p < 0.001), and miR-429 (p = 0.03) in the host liver tissue of the liver metastases. Colorectal liver and lung metastases have a unique miRNA expression profile. miRNA expression in the host tissue of colorectal liver metastases seems to be able to influence tumor progression and survival. These findings can be used in the development of tailored therapies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27760147,"Year":2016,"Title":"Diagnostic Potential of Cell-Free and Exosomal MicroRNAs in the Identification of Patients with High-Risk Colorectal Adenomas.","Abstract":"BACKGROUND: Although there is a growing interest in developing circulating microRNA (miRNA) as noninvasive diagnostic biomarkers for the detection of high-risk colorectal adenomas and early-stage CRCs, but the comparative diagnostic significance of serum vs. exosomal miRNAs remains unexplored. METHODS: Based upon published literature, we performed an initial discovery step by investigating the expression of a miRNA panel in 20 normal colonic mucosa, 27 adenomas, and 19 CRC tissues. We performed subsequent validation by quantifying expression of candidate miRNAs in total serum and in exosomes from 26 adenoma patients and 47 healthy controls, and evaluated their clinical significance and potential diagnostic value in colorectal adenomas. RESULTS: We observed that the expression of four miRNAs, miR-21, miR-29a, miR-92a, and miR-135b, was significantly higher in colorectal adenomas vs. normal colonic mucosa. During validation, expression of miR-21, miR-29a and miR-92a in serum was significantly higher in adenomas vs. healthy controls, significantly correlated with adenoma size and total adenoma number within the colorectum, and significantly discriminated patients with advanced adenomas. In contrast, although exosomal miR-21 and miR-29a levels in adenoma patients were significantly higher than those of healthy volunteers, only exosomal miR-21 significantly correlated with adenoma size and total adenoma number, and could discriminate patients with high-risk adenomas. CONCLUSION: Compared to exosomal miRNAs, serum levels of miR-21, miR-29a and miR-92a are superior diagnostic biomarkers in patients with high-risk adenomatous polyps.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27729841,"Year":2016,"Title":"In Silico Study of miRNA Based Gene Regulation, Involved in Solid Cancer, by the Assistance of Argonaute Protein.","Abstract":"Solid tumor is generally observed in tissues of epithelial or endothelial cells of lung, breast, prostate, pancreases, colorectal, stomach, and bladder, where several genes transcription is regulated by the microRNAs (miRNAs). Argonaute (AGO) protein is a family of protein which assists in miRNAs to bind with mRNAs of the target genes. Hence, study of the binding mechanism between AGO protein and miRNAs, and also with miRNAs-mRNAs duplex is crucial for understanding the RNA silencing mechanism. In the current work, 64 genes and 23 miRNAs have been selected from literatures, whose deregulation is well established in seven types of solid cancer like lung, breast, prostate, pancreases, colorectal, stomach, and bladder cancer. In silico study reveals, miRNAs namely, miR-106a, miR-21, and miR-29b-2 have a strong binding affinity towards PTEN, TGFBR2, and VEGFA genes, respectively, suggested as important factors in RNA silencing mechanism. Furthermore, interaction between AGO protein (PDB ID-3F73, chain A) with selected miRNAs and with miRNAs-mRNAs duplex were studied computationally to understand their binding at molecular level. The residual interaction and hydrogen bonding are inspected in Discovery Studio 3.5 suites. The current investigation throws light on understanding miRNAs based gene silencing mechanism in solid cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27672217,"Year":2017,"Title":"The role of miRNA-21 and epithelial mesenchymal transition (EMT) process in colorectal cancer.","Abstract":"AIMS: The study was conducted to assess the expression levels of epithelial mesenchymal transition (EMT) proteins (E-cadherin, N-cadherin, snail-1 and vimentin) and miRNA-21. In addition, we correlated these data with clinicopathological features in Colorectal cancer. METHODS: H&E slides from a total of 59 formalin fixed paraffin embedded tissue blocks were examined by a pathologist to demarcate normal and tumour regions. Immunohistochemical analysis of mismatch repair proteins (MLH1, MSH2 and MSH6) and EMT markers (E-cadherin, N-cadherin, snail-1 and vimentin) was performed. The miRNA-21 expression levels were determined using qRT-PCR and the data was analysed using the relative quantification method. The Fisher's exact and Pearson's chi(2) tests were used to correlate snail-1, E-cadherin, miRNA-21 and clinicopathological data. RESULTS: Our results showed a statistically significant correlation between high miRNA-21 expression levels and E-cadherin positive cases. There was also an association between high miRNA-21 expression levels and negative snail-1 expression. No significant correlation was seen between miRNA-21 expression levels and clinicopathological features. Moreover, high expression levels of miRNA-21 were significantly associated with the sporadic cases. CONCLUSIONS: Our data suggest that miRNA-21 in association with E-cadherin and snail-1 does not play a significant role in the development and progression of this disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27565378,"Year":2016,"Title":"Investigating intra-tumor heterogeneity and expression gradients of miR-21, miR-92a and miR-200c and their potential of predicting lymph node metastases in early colorectal cancer.","Abstract":"INTRODUCTION: miR-21, miR-92a and miR-200c are regulators of pathways involved in migration, intravasation and metastasis, and their tumor expression levels have been proposed as potential prognostic markers in colorectal cancer (CRC). In two parallel cohorts we examine intra-tumor expression levels in early stage CRC tissue in order to determine intra-tumor heterogeneity, potential systematic intra-tumor expression gradients of the miRNAs and to investigate the association to metastatic disease in early stage CRC. MATERIAL AND METHODS: Two parallel studies on archived formalin-fixed paraffin-embedded (FFPE) CRC tissue. Intra-tumor and inter-patient variances were analyzed in 9 early metastatic CRCs by measuring expression levels by qRT-PCR on isolated tissue samples from luminal, central and invasive border zones. Associations between miRNA expression levels and early metastasizing tumors was investigated in FFPE tissue from invasive border and central tumor zones from 47 early metastatic CRCs matched with 47 non-metastatic CRCs. Intra-tumor expression gradients were analyzed on both cohorts. RESULTS: Mean intra-tumor coefficient of variation in the heterogeneity cohort was 38.5% (range: 33.1-49.0%) only slightly less than variation between patients (45.1%, range 37.0-49.5%). We demonstrated systematic expression gradients between tumor zones equal to a 3.23 (p=0.003) and 1.36 (p=0.014) fold lower expression in invasive areas for miR-200c, 1.52 (p<0.001) and 1.27 (p=0.021) fold lower expression in invasive areas for miR-92a. For miR-21 we found a 1.75 (p<0.001) and 1.21 (p=0.064) fold higher expression in invasive areas compared to luminal and central zones, respectively. No significant difference in expression levels between metastatic and non-metastatic tumors was demonstrated, nor a difference in intra-tumor gradients between metastatic and non-metastatic tumors. CONCLUSION: This study provides evidence for moderate intra-tumor and inter-patient heterogeneities of three well-described potential prognostic markers in CRC. We demonstrate intra-tumor expression gradients indicating a differentiated expression of the target miRNAs between functional tumor zones, but the potential role as markers of early metastatic disease is still not fully clarified.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27495250,"Year":2016,"Title":"MicroRNA-21 promotes proliferation, migration, and invasion of colorectal cancer, and tumor growth associated with down-regulation of sec23a expression.","Abstract":"BACKGROUND: MicroRNA-21 (miR-21) is up-regulated in many cancers, including colorectal cancer (CRC). Nevertheless, the function of miR-21 in CRC and the mechanism underlying that function is still unclear. METHODS: After analyzing the expression of miR-21 and Sec23A in CRC cell lines, we transfected the highest miR-21 expressing cell line, SW-480, with a plasmid containing an miR-21 inhibitor and the lowest miR-21 expressing cell line, DLD-1, with a plasmid containing an miR-21 mimic and measured the effects on the expression of Sec23A and on cell proliferation, migration, and invasion. We also evaluated the effect of knocking down Sec23A on miR-21 expression and its effects on cell proliferation, migration, and invasion. Finally, we assessed the effect of miR-21 in a xenograft tumor model in mice. Tumor tissues from these mice were subjected to immunohistochemical staining to detect the expression of Sec23A. RESULTS: Genetic deletion of miR-21 suppressed the proliferation, migration, and invasion of SW-480 cells, while over-expression of miR-21 promoted proliferation, migration, and invasion of DLD-1 cells. Inhibition of miR-21 increased the expression of Sec23A protein in SW-480 cells while over-expression of miR-21 significantly suppressed the expression of Sec23A protein and Sec23A mRNA in DLD-1 cells. Knockdown of Sec23A increased the expression of miR-21 in SW480 and DLD-1 cells and their proliferation (DLD-1 only), migration, and invasion. Over-expression of miR-21 promoted tumor growth in BALB/c nude mice and suppressed tumor expression of Sec23A. CONCLUSION: These findings provide novel insight into the molecular functions of miR-21 in CRC, which may serve as a potential interesting target.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27471839,"Year":2016,"Title":"A Highly Predictive Model for Diagnosis of Colorectal Neoplasms Using Plasma MicroRNA: Improving Specificity and Sensitivity.","Abstract":"OBJECTIVE: To develop a plasma-based microRNA (miRNA) diagnostic assay specific for colorectal neoplasms, building upon our prior work. BACKGROUND: Colorectal neoplasms [colorectal cancer (CRC) and colorectal advanced adenoma (CAA)] frequently develop in individuals at ages when other common cancers also occur. Current screening methods lack sensitivity, specificity, and have poor patient compliance. METHODS: Plasma was screened for 380 miRNAs using microfluidic array technology from a \"Training\" cohort of 60 patients, (10 each) control, CRC, CAA, breast cancer, pancreatic cancer, and lung cancer. We identified uniquely dysregulated miRNAs specific for colorectal neoplasia (P < 0.05, false discovery rate: 5%, adjusted alpha = 0.0038). These miRNAs were evaluated using single assays in a \"Test\" cohort of 120 patients. A mathematical model was developed to predict blinded sample identity in a 150 patient \"Validation\" cohort using repeat-sub-sampling validation of the testing dataset with 1000 iterations each to assess model detection accuracy. RESULTS: Seven miRNAs (miR-21, miR-29c, miR-122, miR-192, miR-346, miR-372, and miR-374a) were selected based upon P value, area under the curve (AUC), fold change, and biological plausibility. Area under the curve (+/-95% confidence interval) for \"Test\" cohort comparisons were 0.91 (0.85-0.96) between all neoplasia and controls, 0.79 (0.70-0.88) between colorectal neoplasia and other cancers, and 0.98 (0.96-1.0) between CRC and colorectal adenomas. In our \"Validation\" cohort, our mathematical model predicted blinded sample identity with 69% to 77% accuracy, 67% to 76% accuracy, and 86% to 90% accuracy for each comparison, respectively. CONCLUSIONS: Our plasma miRNA assay and prediction model differentiate colorectal neoplasia from patients with other neoplasms and from controls with higher sensitivity and specificity compared with current clinical standards.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27432735,"Year":2017,"Title":"Investigation of MicroRNA-21 Expression Levels in Serum and Stool as a Potential Non-Invasive Biomarker for Diagnosis of Colorectal Cancer.","Abstract":"BACKGROUND: Most cancer studies focus on exploring non-invasive biomarkers for cancer detection. In the present study, we sought to investigate the expression level of microRNA-21 (miR-21), as a potential diagnostic marker, in serum and stool samples from 40 patients with colorectal cancer (CRC) and 40 healthy controls. METHODS: Quantitative real-time RT-PCR was applied to determine the relative expression level of miR-21 in serum and stool. At the same time, the sensitivity and specificity of this marker was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: miR-21 expression levels of serum and stool were up-regulated 12.1 (P<0.05, 95% CI: 5.774-34.045) and 10.0 (P<0.05, 95% CI: 0.351-16.260) times in CRC patients, respectively, when compared to the control group. The sensitivity and specificity of miR-21 was found to be 86.05% and 72.97%, respectively (an area under the ROC curve [AUC] of 0.783). The stool miR-21 level in CRC patients was much higher than that in the healthy controls, showing a sensitivity of 86.05% and a specificity of 81.08% (AUC: 0.829). The expression level of miR-21 in stool was able to significantly distinguish CRC tumor, node, metastasis stages III-IV from stages I-II, with a sensitivity and specificity of 88.1% and 81.6%, respectively (AUC: 0.872). CONCLUSION: The results of this study indicated that miR-21 expression levels in serum and stool can be considered as a potential diagnostic biomarker for the diagnosis of CRC patients. However, more studies are required to confirm the validity of miR-21 as a valuable non-invasive diagnostic tool for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27380811,"Year":2016,"Title":"Serum microRNA expression profile as a diagnostic panel for gastric cancer.","Abstract":"PURPOSE: Previously, we identified six miRNAs that are differentially expressed in colorectal cancer compared with healthy controls. Here, we tested them in gastric cancer GC. METHODS: We performed quantitative RT-PCR on serum samples from 92 patients with gastric cancer and 89 controls for the six miRNAs, and analyzed their risk scores to evaluate the diagnostic value of the serum miRNA profiling system. RESULTS: After a two-phase selection and validation process, five miRNAs were found to significantly differ in expression between gastric cancer samples and control samples, including miR-21, miR-31, miR-92a, miR-181b, and miR-203. Risk score analysis showed that this miRNA panel could distinguish gastric cancer cases from controls with high sensitivity and specificity. Under receiver operating characteristic curves, areas under the curve for tumor identification were 0.933 (95% confidence interval [CI]: 0.86-1.007) for the training set and 0.919 (95% CI: 0.863-0.975) for the validation set-markedly higher than those of carcinoembryonic antigen (0.624) and carbohydrate antigen 19-9 (0.603). CONCLUSIONS: The signature of these five miRNAs is a novel and noninvasive biomarker for gastric cancer, and could facilitate and simplify its diagnosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27364574,"Year":2016,"Title":"Locked nucleic acid anti-miR-21 inhibits cell growth and invasive behaviors of a colorectal adenocarcinoma cell line: LNA-anti-miR as a novel approach.","Abstract":"Colorectal cancer (CRC) is the third leading cause of cancer-related death and has an extremely poor prognosis. Dysregulation of microRNAs (miRNAs) has been shown to be involved in the pathogenesis and progression of many malignancies. Recent data suggest that microRNA-21 (miR-21) is significantly elevated in different types of cancer, especially colon adenocarcinoma. Against this background, locked nucleic acid (LNA)-modified oligonucleotides have recently been suggested as a novel approach for targeting miRNAs as antisense-based gene silencing. The aim of the current study was to explore the functional role of LNA-anti-miR-21 in a colon adenocarcinoma LS174T cell line. LS174T cells were transfected with LNA-anti-miR-21 for 24, 48 and 72 h. Quantitative real-time reverse transcriptase-PCR (qRT-PCR) was performed to assess miR-21 expression by LNA-anti-miR-21. The viability of the cells was evaluated by MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay and Annexin V/propidium iodide staining assay was used to detect apoptosis. Moreover, invasive behavior of the cells was evaluated before and after therapy by transwell assay. LNA-anti-miR-21 was successfully transfected in human LS174T cells and suppressed the endogenous miR-21. LNA-anti-miR-21 inhibited the cells' growth followed by induction of apoptosis. LNA-anti-miR-21 (50 pmol/mul) reduced the invasive behaviors of LS174T cells after 24 h, compared with untreated cells and scrambled LNA-transfected cells. However, this effect was more pronounced after 72 h. Our findings suggest the therapeutic potential of LNA-anti-miR-21 in a colon adenocarcinoma for targeting miR-21 expression. Further studies are warranted to investigate the molecular mechanisms underlying this novel inhibitor in colorectal cancer to establish its potential value for treatment of CRC patients with high miR-21 expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27350731,"Year":2016,"Title":"MicroRNA-21 promotes phosphatase gene and protein kinase B/phosphatidylinositol 3-kinase expression in colorectal cancer.","Abstract":"AIM: To explore the regulatory mechanism of the target gene of microRNA-21 (miR-21), phosphatase gene (PTEN), and its downstream proteins, protein kinase B (AKT) and phosphatidylinositol 3-kinase (PI3K), in colorectal cancer (CRC) cells. METHODS: Quantitative real-time PCR (qRT-PCR) and Western blot were used to detect the expression levels of miR-21 and PTEN in HCT116, HT29, Colo32 and SW480 CRC cell lines. Also, the expression levels of PTEN mRNA and its downstream proteins AKT and PI3K in HCT116 cells after downregulating miR-21 were investigated. RESULTS: Comparing the miR-21 expression in CRC cells, the expression levels of miR-21 were highest in HCT116 cells, and the expression levels of miR-21 were lowest in SW480 cells. In comparing miR-21 and PTEN expression in CRC cells, we found that the protein expression levels of miR-21 and PTEN were inversely correlated (P < 0.05); when miR-21 expression was reduced, mRNA expression levels of PTEN did not significantly change (P > 0.05), but the expression levels of its protein significantly increased (P < 0.05). In comparing the levels of PTEN protein and downstream AKT and PI3K in HCT116 cells after downregulation of miR-21 expression, the levels of AKT and PI3K protein expression significantly decreased (P < 0.05). CONCLUSION: PTEN is one of the direct target genes of miR-21. Thus, phosphatase gene and its downstream AKT and PI3K expression levels can be regulated by regulating the expression levels of miR-21, which in turn regulates the development of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27349026,"Year":2016,"Title":"Plasma Expression Levels of Circulating miR-21 are not Useful for Diagnosing and Monitoring Colorectal Cancer.","Abstract":"BACKGROUND: Recent evidence suggests that microRNAs play an important role in cancer diagnostics. We assessed plasma microRNA-21 levels in patients with colorectal cancer (CRC) at different stages and in patients with benign polyps. METHODS: Plasma levels of miR-21 were assessed by quantitative reverse transcription polymerase chain reaction assay in plasma samples of 76 CRC patients and in 20 patients with benign polyps. Differences between groups were evaluated with Mann-Whitney and Kruskal-Wallis tests. RESULTS: No significant differences of miR-21 plasma levels were observed between CRC patients and subjects with benign polyps (p > 0.05). Also, no significant differences were found between CRC patients with advanced (III-IV) or early cancer stages (I-II) (p > 0.05). CONCLUSIONS: These results do not support the hypothesis that circulating miR-21 expression is increased in adenoma-carcinoma-advanced carcinoma sequence. Accordingly, plasma miR-21 assessment does not appear to be a useful biomarker for diagnosing and staging CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27258547,"Year":2016,"Title":"Intratumoral Heterogeneity of MicroRNA Expression in Rectal Cancer.","Abstract":"INTRODUCTION: An increasing number of studies have investigated microRNAs (miRNAs) as potential markers of diagnosis, treatment and prognosis. So far, agreement between studies has been minimal, which may in part be explained by intratumoral heterogeneity of miRNA expression. The aim of the present study was to assess the heterogeneity of a panel of selected miRNAs in rectal cancer, using two different technical approaches. MATERIALS AND METHODS: The expression of the investigated miRNAs was analysed by real-time quantitative polymerase chain reaction (RT-qPCR) and in situ hybridization (ISH) in tumour specimens from 27 patients with T3-4 rectal cancer. From each tumour, tissue from three different luminal localisations was examined. Inter- and intra-patient variability was assessed by calculating intraclass correlation coefficients (ICCs). Correlations between RT-qPCR and ISH were evaluated using Spearman's correlation. RESULTS: ICCsingle (one sample from each patient) was higher than 50% for miRNA-21 and miRNA-31. For miRNA-125b, miRNA-145, and miRNA-630, ICCsingle was lower than 50%. The ICCmean (mean of three samples from each patient) was higher than 50% for miRNA-21(RT-qPCR and ISH), miRNA-125b (RT-qPCR and ISH), miRNA-145 (ISH), miRNA-630 (RT-qPCR), and miRNA-31 (RT-qPCR). For miRNA-145 (RT-qPCR) and miRNA-630 (ISH), ICCmean was lower than 50%. Spearman correlation coefficients, comparing results obtained by RT-qPCR and ISH, respectively, ranged from 0.084 to 0.325 for the mean value from each patient, and from -0.085 to 0.515 in the section including the deepest part of the tumour. CONCLUSION: Intratumoral heterogeneity may influence the measurement of miRNA expression and consequently the number of samples needed for representative estimates. Our findings with two different methods suggest that one sample is sufficient for adequate assessment of miRNA-21 and miRNA-31, whereas more samples would improve the assessment of miRNA-125b, miRNA-145, and miRNA-630. Interestingly, we found a poor correlation between the expression estimates obtained by RT-qPCR and ISH, respectively.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27247088,"Year":2016,"Title":"Identifying High-Risk Stage II Colon Cancer Patients: A Three-MicroRNA-Based Score as a Prognostic Biomarker.","Abstract":"BACKGROUND: The potential benefit of adjuvant chemotherapy in surgically resected patients with stage II colorectal cancer is controversial. The current guidelines, which are based solely on clinical factors, have limited usefulness, and a clear need exists for biomarkers to supplement the clinical information. MicroRNAs (miRNAs) have previously been shown to be useful cancer biomarkers. In the present study, we assessed the usefulness of a miRNA score to help identify the subset of high-risk patients likely to benefit from adjuvant chemotherapy. PATIENTS AND METHODS: Six miRNAs previously identified as prognostic markers in Asian patients (miR-21-5p, miR-20a-5p, miR-103a-3p, miR-106b-5p, miR-143-5p, and miR-215) were studied in tumor samples from 71 white patients with stage II colon cancer. RESULTS: Three miRNAs (miR-103a-3p, miR-143-5p, and miR-215) emerged as independent prognostic markers on multivariate analysis and were used to construct a miRNA-based score that classified patients into high- and low-risk groups. The patients in the high-risk group had significantly shorter disease-free survival compared with their low-risk counterparts (P = .003). The time-dependent receiver operating characteristic curve analysis showed that our 3-miRNA score improved the prediction of outcome when added to the clinical features (P = .023). CONCLUSION: Our 3-miRNA score added valuable prognostic information to the clinical features in stage II colon cancer. Further research in this field could provide useful tools to determine whether adjuvant chemotherapy would benefit patients with stage II colon cancer after surgery.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27222255,"Year":2016,"Title":"Downregulation of lncRNA CASC2 by microRNA-21 increases the proliferation and migration of renal cell carcinoma cells.","Abstract":"Several long non-coding RNAs (lncRNAs) have been identified that may have a crucial role in tumor progression and metastasis. The lncRNA cancer susceptibility candidate 2 (CASC2) has previously been reported to act as a tumor suppressor gene in glioma and colorectal cancer. However, the expression and function of CASC2 in renal cell carcinoma (RCC) remains to be elucidated. The present study confirmed that CASC2 was downregulated in human RCC tissues and human RCC cell lines (786O and A498). Restoration of CASC2 expression via transfection with a pcDNA3.1(+)CASC2 vector was able to inhibit cell proliferation and migration in 786O and A498 cells, as compared with in the cells transfected with a pcDNA3.1(+) empty vector. MicroRNA21 (miR21) has been reported to be upregulated in human RCC tissues and cell lines, and is associated with the malignant progression of RCC. In the present study, bioinformatics analysis and dualluciferase reporter assays confirmed that CASC2 was a direct target gene of miR21. miR21 was able to decrease the expression of CASC2 in 786O and A498 cells. Furthermore, overexpression of miR21 partly abrogated CASC2mediated inhibition of 786O and A498 cell proliferation and migration. The present study provides evidence indicating that CASC2 targeted by miR21 acts as a tumor suppressor in RCC. Therefore, CASC2 may be considered a novel target for the diagnosis and treatment of RCC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27153478,"Year":2016,"Title":"Associations between markers of colorectal cancer stem cells, mutation, microRNA and the clinical features of ulcerative colitis.","Abstract":"AIM: Several factors have been implicated in the pathogenesis of colorectal cancer (CRC) associated with ulcerative colitis (UC). We investigated markers of cancer cell pluripotency, including CD44 and CD166, microRNA-21 (miR-21) and microRNA-215 (miR-215), and APC, K-ras and DCC mutations in biopsy specimens from patients with UC to evaluate any correlations with clinical risk factors. METHOD: We observed 18 patients with UC and collected two biopsy specimens from each patient at diagnosis and at a follow-up end-point. We examined the expression of CD44, CD166, miR-21 and miR-215, and APC, K-ras and DCC mutations. We compared these markers at the two time points and assessed their associations with clinical characteristics, including the duration of colitis, histological alterations and the age of the patient at the onset of UC. RESULTS: Most (16/18) patients had alleviation of mucosal inflammation or remained stable during follow-up; one patient developed dysplasia and one had severe aggravation of the lesion during follow-up. Enhanced expression of CD44, CD166 and miR-21 with miR-215 was found in the specimens obtained at follow-up, despite alleviation of mucosal lesions. Coherence of cancer stem cell markers and miRNAs was seen in patients who had significant worsening of inflammation, dysplasia and a long duration of colitis. APC mutation occurred in only one patient; this patient had the longest duration of UC (23 years). CONCLUSION: Enhanced markers of CRC in follow-up colonic mucosal samples support the conclusion that the duration of UC plays the most important role in UC-related carcinogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27142899,"Year":2016,"Title":"Serological under expression of microRNA-21, microRNA-34a and microRNA-126 in colorectal cancer.","Abstract":"PURPOSE: This paper describes the ability of miRNA value predict oncological outcomes in CRC patients and correlates to clinical and pathologic variables. METHODS: We prospectively analyzed the serological expression of microRNA-21, microRNA-34a, and microRNA-126 in 37 stage II - IV CRC patients and correlate to seven fit counterparts. Serological microRNAs were extracted using the miRNeasy Mini Kit(r) (Qiagen, Hilden, Germany). Quantification of microRNAs was performed using TaqMan Master Mix(r) reagent (Applied Biosystems, USA). RESULTS: We obtained serological underexpression microRNA-21, microRNA-34a, and microRNA-126 in CRC group. However, miRNAs serological values do not impact prognosis. Furthermore, miRNAs was not influenced by CEA values, TNM staging, and histological subtype. CONCLUSION: Despite lower expression of miR-21, miR-34a and miR-126 in the CRC group, no association with poor prognosis was found.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27135244,"Year":2016,"Title":"Circulating Serum miRNAs as Diagnostic Markers for Colorectal Cancer.","Abstract":"AIM: The study was designed to assess the possibility of using circulating miRNAs (serum miRNAs) as diagnostic biomarkers in colorectal cancer (CRC) and to identify their possibility as candidates for targeted therapy. METHODS: The study involved two sample sets: 1- a training set which included 90 patients with colorectal related disease (30 with CRC, 18 with inflammatory bowel disease (IBD), 18 with colonic polyps (CP) and 24 with different colonic symptoms but without any colonoscopic abnormality who were enrolled as control group) and 2- a validation set which included 100 CRC patients. Serum miRNAs were extracted from all subjects to assess the expression profiles for the following miRNAs (miR-17, miR-18a, miR-19a, miR-19b, miR-20a, miR-21, miR-146a, miR-223, miR-24, miR-454, miR-183, miR-135a, miR- 135b and miR- 92a) using the custom miScript miRNA PCR-based sybergreen array. The area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic performance of the studied miRNAs for colorectal cancer diagnosis. RESULTS: Data analysis of miRNA from the training set showed that; compared to control group, only miR-19b was significantly up-regulated in patients with IBD group (fold change = 5.24, p = 0.016), whereas in patients with colonic polyps, miR-18a was significantly up-regulated (fold change = 3.49, p-value = 0.018). On the other hand, miR-17, miR-19a, miR-20a and miR-223 were significantly up-regulated (fold change = 2.35, 3.07, 2.38 and 10.35; respectively and p-value = 0.02, 0.015, 0.017 and 0.016; respectively in CRC patients. However, the validation set showed that only miR-223 was significantly up-regulated in CRC patients (fold change = 4.06, p-value = 0.04). CONCLUSION: Aberrant miRNA expressions are highly involved in the cascade of colorectal carcinogenesis. We have found that (miR-17, miR-19a, miR-20a and miR-223) could be used as diagnostic biomarkers for CRC. On the other hand, miR-19b and miR-18a could be used as diagnostic biomarkers for CP and IBD respectively.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27082112,"Year":2016,"Title":"Infinity: An In-Silico Tool for Genome-Wide Prediction of Specific DNA Matrices in miRNA Genomic Loci.","Abstract":"MOTIVATION: miRNAs are potent regulators of gene expression and modulate multiple cellular processes in physiology and pathology. Deregulation of miRNAs expression has been found in various cancer types, thus, miRNAs may be potential targets for cancer therapy. However, the mechanisms through which miRNAs are regulated in cancer remain unclear. Therefore, the identification of transcriptional factor-miRNA crosstalk is one of the most update aspects of the study of miRNAs regulation. RESULTS: In the present study we describe the development of a fast and user-friendly software, named infinity, able to find the presence of DNA matrices, such as binding sequences for transcriptional factors, on ~65kb (kilobase) of 939 human miRNA genomic sequences, simultaneously. Of note, the power of this software has been validated in vivo by performing chromatin immunoprecipitation assays on a subset of new in silico identified target sequences (CCAAT) for the transcription factor NF-Y on colon cancer deregulated miRNA loci. Moreover, for the first time, we have demonstrated that NF-Y, through its CCAAT binding activity, regulates the expression of miRNA-181a, -181b, -21, -17, -130b, -301b in colon cancer cells. CONCLUSIONS: The infinity software that we have developed is a powerful tool to underscore new TF/miRNA regulatory networks. AVAILABILITY AND IMPLEMENTATION: Infinity was implemented in pure Java using Eclipse framework, and runs on Linux and MS Windows machine, with MySQL database. The software is freely available on the web at https://github.com/bio-devel/infinity. The website is implemented in JavaScript, PHP and HTML with all major browsers supported.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27022275,"Year":2016,"Title":"Screening miRNAs for early diagnosis of colorectal cancer by small RNA deep sequencing and evaluation in a Chinese patient population.","Abstract":"PURPOSE: This study aims to screen microRNAs (miRNAs), for an early diagnosis of colorectal cancer, by deep sequencing and evaluation of total miRNAs using clinical samples from a Chinese patient population. METHODS: Total small RNAs from normal colonic mucosa, colonic adenomas, and colorectal cancer tissues were prepared for miRNA analysis by deep sequencing. The sequencing data were then analyzed by bioinformatics for candidate diagnostic miRNAs, which were further validated for their up- or downregulation status. RESULTS: Comparison of cancer tissues with normal mucosa identified 99 upregulated and 90 downregulated miRNAs. Comparison of adenomas and normal mucosa found 114 upregulated and 107 downregulated miRNAs. Comparison of cancer and adenoma tissues found 70 upregulated and 27 downregulated miRNAs. Selected up- and downregulated miRNAs were validated for their expressions in 12 cases of patients with cancer and polyps. Specifically, for the upregulated miRNAs, miR-18a-5p and miR-21-3p were significantly upregulated in adenomas and cancer tissues, compared with the normal mucosa; miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, and miR-200c-3p were significantly upregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissues when compared with the normal mucosa. miR-183-5p and miR-96-5p were significantly upregulated in adenoma tissues when compared with normal mucosa, but these differences were not significant in cancer tissues when compared to normal mucosa. For the downregulated miRNAs, miR-133a-3p was significantly downregulated in both adenoma and cancer tissues when compared to normal mucosa; miR-204-5p, miR-125b-5p, miR-139-5p, miR-100-5p, and miR-30a-5p were significantly downregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissue compared to normal mucosa. CONCLUSION: The findings of this study show that a number of miRNAs might be important in the diagnosis and prognosis of colorectal cancer in Chinese patients using the method of small RNA deep sequencing. Upregulation of miR-18a-5p and miR-21-3p or downregulation of miR-133a-3p in adenoma and cancer tissues may serve as an index for early screening of colorectal cancer. Other miRNAs, such as miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, miR-200c-3p, miR-183-5p, and miR-96-5p, which were either up- or downregulated, in cancer tissues, but not in adenoma tissues, have limited significance in early diagnosis. Further study is needed to determine a screening index with diagnostic value.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":27013928,"Year":2016,"Title":"Time course analysis based on gene expression profile and identification of target molecules for colorectal cancer.","Abstract":"BACKGROUND: The study aimed to investigate the expression changes of genes in colorectal cancer (CRC) and screen the potential molecular targets. METHODS: The GSE37178 of mRNA expression profile including the CRC samples extracted by surgical resection and the paired normal samples was downloaded from Gene Expression Omnibus database. The genes whose expressions were changed at four different time points were screened and clustered using Mfuzz package. Then DAVID was used to perform the functional and pathway enrichment analysis for genes in different clusters. The protein-protein interaction (PPI) networks were constructed for genes in the clusters according to the STRING database. Furthermore, the related-transcription factors (TFs) and microRNAs (miRNAs) were obtained based on the resources in databases and then were combined with the PPI networks in each cluster to construct the integrated network containing genes, TFs and miRNAs. RESULTS: As a result, 314 genes were clustered into four groups. Genes in cluster 1 and cluster 2 showed a decreasing trend, while genes in cluster 3 and cluster 4 presented an increasing trend. Then 18 TFs (e.g., TCF4, MEF2C and FOS) and 18 miRNAs (e.g., miR-382, miR-217, miR-1184, miR-326 and miR-330-5p) were identified and three integrated networks for cluster 1, 3, and 4 were constructed. CONCLUSIONS: The results implied that expression of PITX2, VSNL1, TCF4, MEF2C and FOS are time-related and associated with CRC development, accompanied by several miRNAs including miR-382, miR-217, miR-21, miR-1184, miR-326 and miR-330-5p. All of them might be used as potential diagnostic or therapeutic target molecules for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26963002,"Year":2016,"Title":"Expression Profiles of miRNA Subsets Distinguish Human Colorectal Carcinoma and Normal Colonic Mucosa.","Abstract":"OBJECTIVES: MicroRNAs (miRNAs) are small, non-protein-coding RNA molecules that are commonly dysregulated in colorectal tumors. The objective of this study was to identify smaller subsets of highly predictive miRNAs. METHODS: Data come from population-based studies of colorectal cancer conducted in Utah and the Kaiser Permanente Medical Care Program. Tissue samples were available for 1,953 individuals, of which 1,894 had carcinoma tissue and 1,599 had normal mucosa available for statistical analysis. Agilent Human miRNA Microarray V.19.0 was used to generate miRNA expression profiles; validation of expression levels was carried out using quantitative PCR. We used random forest analysis and verified findings with logistic modeling in separate data sets. Important microRNAs are identified and bioinformatics tools are used to identify target genes and related biological pathways. RESULTS: We identified 16 miRNAs for colon and 17 miRNAs for rectal carcinoma that appear to differentiate between carcinoma and normal mucosa; of these, 12 were important for both colon and rectal cancer, hsa-miR-663b, hsa-miR-4539, hsa-miR-17-5p, hsa-miR-20a-5p, hsa-miR-21-5p, hsa-miR-4506, hsa-miR-92a-3p, hsa-miR-93-5p, hsa-miR-145-5p, hsa-miR-3651, hsa-miR-378a-3p, and hsa-miR-378i. Estimated misclassification rates were low at 4.83% and 2.5% among colon and rectal observations, respectively. Among independent observations, logistic modeling reinforced the importance of these miRNAs, finding the primary principal components of their variation statistically significant (P<0.001 among both colon and rectal observations) and again producing low misclassification rates. Repeating our analysis without those miRNAs initially identified as important identified other important miRNAs; however, misclassification rates increased and distinctions between remaining miRNAs in terms of classification importance were reduced. CONCLUSIONS: Our data support the hypothesis that while many miRNAs are dysregulated between carcinoma and normal mucosa, smaller subsets of these miRNAs are useful and informative in discriminating between these tissues.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26958084,"Year":2016,"Title":"Evaluation of Plasma miR-21 and miR-152 as Diagnostic Biomarkers for Common Types of Human Cancers.","Abstract":"Stable blood based miRNA species have allowed for the differentiation of patients with various types of cancer. Therefore, specific blood-based miRNA might be considered as a methodology which could be informative of the presence of cancer potentially from multiple distinct organ sites. Recently, miR-21 has been identified as an \"oncomir\" in various tumors while miR-152 as a tumor suppressor. In this study, we investigated whether circulating miR-21 and miR-152 can be used for early detection of lung cancer (LuCa), colorectal carcinoma (CRC), breast cancer (BrCa) and prostate cancer (PCa), with distinguishing cancer from various benign lesions on these organ sites. We measured the two miRNA levels by using real-time RT-PCR in plasma samples from a total of 204 cancer patients, 159 various benign lesions, and 228 normal subjects. We observed significantly elevated expression of miR-21 and miR-152 in LuCa, CRC, and BrCa when compared with normal controls. We also found upregulation of plasma miR-21 and miR-152 levels in patients with benign lesions of lung and breast, as compared to normal controls, respectively. No significant expression variation of the two miRNAs was observed in PCa or prostatic benign lesions as compared to healthy controls. Receiver operating characteristic (ROC) analyses revealed that miR-21 and/or miR-152 can discriminate LuCa, CRC and BrCa from normal controls. Our results suggest that plasma miR-21 and miR-152 may serve as non-specific noninvasive biomarkers for early screening of LuCa, CRC, and BrCa, but not PCa.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26957558,"Year":2016,"Title":"MicroRNA MIR21 (miR-21) and PTGS2 Expression in Colorectal Cancer and Patient Survival.","Abstract":"PURPOSE: Prostaglandin-endoperoxide synthase 2 (PTGS2, cyclooxygenase-2; a target of aspirin) produces inflammatory mediator prostaglandin E2 (PGE2), and contributes to colorectal neoplasia development. PTGS2-driven inflammatory responses can induce tumor expression of microRNA MIR21 (miR-21) that can increase local PGE2 level by downregulating PGE2-metabolizing enzymes. We hypothesized that the prognostic association of tumor MIR21 expression level in colorectal carcinoma might depend on inflammatory tumor microenvironment and be stronger in tumors expressing high-level PTGS2. EXPERIMENTAL DESIGN: Utilizing 765 rectal and colon cancer specimens in the Nurses' Health Study and the Health Professionals Follow-up Study, we measured MIR21 expression by quantitative reverse transcription PCR, and PTGS2 expression by immunohistochemistry. Cox proportional hazards regression model was used to assess statistical interaction between MIR21 and PTGS2 in colorectal cancer-specific survival analysis, controlling for potential confounders including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation level, and KRAS, BRAF, and PIK3CA mutations. RESULTS: Tumor MIR21 expression level was associated with higher colorectal cancer-specific mortality (Ptrend = 0.029), and there was a statistically significant interaction between MIR21 and PTGS2 (Pinteraction = 0.0004). The association between MIR21 expression and colorectal cancer-specific mortality was statistically significant in PTGS2-high cancers (multivariable hazard ratio of the highest vs. lowest quartile of MIR21, 2.28; 95% confidence interval, 1.42-3.67; Ptrend = 0.0004) but not in PTGS2-absent/low cancers (Ptrend = 0.22). CONCLUSIONS: MIR21 expression level in colorectal carcinoma is associated with worse clinical outcome, and this association is stronger in carcinomas expressing high-level PTGS2, suggesting complex roles of immunity and inflammation in tumor progression. Clin Cancer Res; 22(15); 3841-8. (c)2016 AACR.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26954494,"Year":2016,"Title":"Support Vector Machine Based on microRNA Expression Profiles to Predict Histological Origin of Ampullary Carcinoma: Case Report of a Patient Affected From Adenocarcinoma of the Papilla of Vater With Lynch Syndrome.","Abstract":"Adenocarcinomas of Vater's papilla (PVAC) may originate from either the pancreatic duct or the intestinal epithelium. Conflicting data have been reported about the frequency of the 2 anatomical entities and their influence on patients' prognosis. To ascertain the anatomical origin of PVAC in a family member of a Lynch syndrome kindred, we searched for microRNA (miRNA) expression profiles on resected tumor specimens. The support vector machine was trained on our previous miRNAs expression data sets of pancreatic and colorectal tissue samples and used to classify the site of origin of the tumor in our patient. The support vector machine worked by contrasting the profiles of miRNAs in patients with pancreatic ductal and colorectal cancers to that of our patient, which was finally classified as pancreatic ductal adenocarcinoma accordingly to alterations of 55 miRNAs. The PVAC might be originated from ductal epithelium rather than from the intestinal mucosa of the papilla in the case at issue. Alteration of miR-548b-3p, miR-551a, miR-21, miR-92a, miR-let-7i, and miR-181a* emerged as potentially associated with cancer genetic susceptibility in PVAC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26853468,"Year":2016,"Title":"Inhibition of colon cancer growth by docosahexaenoic acid involves autocrine production of TNFalpha.","Abstract":"The omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has anti-inflammatory and anti-cancer properties. Among pro-inflammatory mediators, tumor necrosis factor alpha (TNFalpha) plays a paradoxical role in cancer biology with induction of cancer cell death or survival depending on the cellular context. The objective of the study was to evaluate the role of TNFalpha in DHA-mediated tumor growth inhibition and colon cancer cell death. The treatment of human colorectal cancer cells, HCT-116 and HCT-8 cells, with DHA triggered apoptosis in autocrine TNFalpha-dependent manner. We demonstrated that DHA-induced increased content of TNFalpha mRNA occurred through a post-transcriptional regulation via the down-regulation of microRNA-21 (miR-21) expression. Treatment with DHA led to nuclear accumulation of Foxo3a that bounds to the miR-21 promoter triggering its transcriptional repression. Moreover, inhibition of RIP1 kinase and AMP-activated protein kinase alpha reduced Foxo3a nuclear-cytoplasmic shuttling and subsequent increase of TNFalpha expression through a decrease of miR-21 expression in DHA-treated colon cancer cells. Finally, we were able to show in HCT-116 xenograft tumor-bearing nude mice that a DHA-enriched diet induced a decrease of human miR-21 expression and an increase of human TNFalpha mRNA expression limiting tumor growth in a cancer cell-derived TNFalpha dependent manner. Altogether, the present work highlights a novel mechanism for anti-cancer action of DHA involving colon cancer cell death mediated through autocrine action of TNFalpha.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26852921,"Year":2016,"Title":"Colorectal cancer characterization and therapeutic target prediction based on microRNA expression profile.","Abstract":"Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer death. However, the molecular mechanisms underlying CRC initiation, growth and metastasis are poorly understood. In this study, based on our previous work for comprehensively analyzing miRNA sequencing data, we examined a series of colorectal cancer microRNAs expression profiles data. Results show that all these CRC samples share the same four pathways including TGF-beta signaling pathway, which is important in colorectal carcinogenesis. Twenty-one microRNAs that evolved in the four overlapped pathways were then discovered. Further analysis selected miR-21 as an important regulator for CRC through TGF-beta pathways. This study develops methods for discovering tumor specific miRNA cluster as biomarker and for screening new cancer therapy targets based on miRNA sequencing.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26845148,"Year":2016,"Title":"MiRNA-21 Expression Decreases from Primary Tumors to Liver Metastases in Colorectal Carcinoma.","Abstract":"OBJECTIVE: Metastasis is the major cause of death in colorectal cancer patients. Expression of certain miRNAs in the primary tumors has been shown to be associated with progression of colorectal cancer and the initiation of metastasis. In this study, we compared miRNA expression in primary colorectal cancer and corresponding liver metastases in order to get an idea of the oncogenic importance of the miRNAs in established metastases. METHODS: We analyzed the expression of miRNA-21, miRNA-31 and miRNA-373 in corresponding formalin-fixed paraffin-embedded (FFPE) tissue samples of primary colorectal cancer, liver metastasis and healthy tissues of 29 patients by quantitative real-time PCR. RESULTS: All three miRNAs were significantly up-regulated in the primary tumor tissues as compared to healthy colon mucosa of the respective patients (p < 0.01). MiRNA-21 and miRNA-31 were also higher expressed in liver metastases as compared to healthy liver tissues (p < 0.01). No significant difference of expression of miRNA-31 and miRNA-373 was observed between primary tumors and metastases. Of note, miRNA-21 expression was significantly reduced in liver metastases as compared to the primary colorectal tumors (p < 0.01). CONCLUSION: In the context of previous studies demonstrating increased miRNA-21 expression in metastatic primary tumors, our findings raise the question whether miRNA-21 might be involved in the initiation but not in the perpetuation and growth of metastases.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26790446,"Year":2016,"Title":"Contribution of in vitro comparison of colorectal carcinoma cells from primary and metastatic lesions to elucidation of mechanisms of tumor progression and response to anticancer therapy.","Abstract":"Colorectal cancer has been a leading cause of cancer-related morbidity and mortality. For the research and individualization of therapy, primary cell lines of the colorectal cancer appear to be still an invaluable tool. We evaluated the differences in metastatic potential between four isolated primary colon cancer cells and cells derived from their lymph node metastasis. These results were compared with correspond immortalized cells-SW480 and SW620, respectively. The ability to migrate was tested using real-time measurement in xCELLigence system. Expressions of molecules involved in adhesion and invasion processes were examined using RT-PCR and western blot analysis. Furthermore, impact of cytotoxic effect of selected chemotherapeutics (irinotecan, oxaliplatin) and biological therapy (bevacizumab, cetuximab, panitumumab) was assessed by the WST assay. As expected, cell lines derived from lymph node migrated more aggressively and higher expression of adhesion molecules ICAM-1, EpCAM, and N-cadherin was detected. The expression of MMP-2 and -9 was elevated, on the other hand, in cell lines derived from primary tumor cancer cells as well as the expression of miR-21, miR-29a, and miR-200a. The most pronounced cytotoxic effect has been recorded with oxaliplatin and irinotecan (IC50 = 48.23 resp. 0.11 mug/ml), especially in cells originating from lymph node metastases. In total, comparison of isolated cell lines and immortalized cell lines has shown many similarities, as well as several differences. Adhesion/invasion molecules and several miRNAs, which play an important role in tumor development and the invasive and migratory behavior, could be a useful therapeutic target in malignant colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26787105,"Year":2016,"Title":"The prognostic effect of PTEN expression status in colorectal cancer development and evaluation of factors affecting it: miR-21 and promoter methylation.","Abstract":"BACKGROUND: PTEN is a tumor suppressor gene which is involved in cellular proliferation, differentiation, and apoptosis. Loss or down-regulation of PTEN plays an important role in human cancers development. In this study, we investigated the effect of miR-21 and promoter methylation on the PTEN expression status in CRC tissues and analyzed association of the PTEN expression status with clinicopathological features in patients with CRC. RESULTS: The PTEN expression was positively detected in 67.2 % CRC tissues and all adjacent non-cancerous samples. PTEN mRNA level was negatively correlated with miR-21 level (r = -0.595, P < 0.001). PTEN expression was also correlated directly with the PTEN mRNA level (r = 0.583, P < 0.001) and conversely with miR-21 level (r = -0.632, P < 0.001). PTEN Promoter methylation was significantly associated with PTEN expression status (p = 0.013). PTEN expression was negatively associated with tumor size (p = 0.007) and advanced tumor stage (P = 0.011). Multivariate analysis indicated that tumor stage, tumor differentiation and PTEN expression status were independent prognostic factors for overall carcinoma in CRC patients (P < 0.05). The Kaplan-Meier curve indicated a negative correlation between PTEN expression levels and survival of CRC patients (P = 0.013). CONCLUSIONS: This study suggests a high frequency of miR-21 overexpression and aberrant promoter methylation in down-regulation of PTEN expression in colorectal carcinoma. Loss of PTEN may be a prognostic factor for patients with CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26781797,"Year":2015,"Title":"Serum expression levels of miR-17, miR-21, and miR-92 as potential biomarkers for recurrence after adjuvant chemotherapy in colon cancer patients.","Abstract":"The present study examined whether miR-17, miR-21, miR-29a, and miR-92 that are dysregulated in colon cancer (CC) can serve as potential predictive markers for relapse of disease after radical surgery and adjuvant chemotherapy. Real-time reverse transcription quantitative polymerase chain reaction was used to measure the expression levels of the miRNAs in serum samples from 37 patients with CC and 7 healthy individuals, tested as a control group. The area under the receiver operating characteristic curve (AUC) was then used to evaluate the predictive performance of the four miRNAs alone or in combination and compare it with carcinoembryonic antigen. The expression of miR-17, miR-21 and miR-92 were significantly higher in serum of patients with disease relapse. The AUCs for miR-17, miR-21, miR-92 for Nx patients were 0.844, 0.948, and 0.935, respectively (p < 0.05). Combining the four miRNAs for stage III patients increased the diagnostic performance, yielding an AUC of 0.881, with a sensitivity of 83.3% and a specificity of 85.7% (p < 0.05). Our study suggests that the expression levels of serum miR-21, miR-17, and miR-92 in patients with CC who underwent radical surgery and adjuvant chemotherapy may have diagnostic value for differentiating between recurred and non-recurred patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26716902,"Year":2016,"Title":"Leukemia inhibitory factor promotes EMT through STAT3-dependent miR-21 induction.","Abstract":"Leukemia inhibitory factor (LIF) is a multi-function cytokine. Its role in cancer is not well-understood. Recent studies including ours show that LIF is frequently overexpressed in many types of human tumors and promotes the progression and metastasis of tumors. However, the underlying mechanism of LIF's promoting effects on tumor progression and metastasis is poorly defined. Epithelial-mesenchymal transition (EMT) plays an important role in tumor metastasis. This study reports that LIF promotes EMT in human tumor cells. Overexpression of LIF promotes tumor cells to acquire mesenchymal features, including morphological changes of cells from epithelial-like to mesenchymal-like, increased expression levels of mesenchymal markers and decreased expression of epithelial markers. Knockdown of endogenous LIF reverses EMT in cancer cells. We further identified that LIF induces the expression of microRNA-21 (miR-21), which in turn mediates the promoting effect of LIF on EMT. LIF induces miR-21 expression through the activation of STAT3. Importantly, blocking miR-21 function greatly abolished the promoting effect of LIF on EMT and the migration ability of cancer cells. Taken together, results from this study identified an important function and a novel underlying mechanism of LIF in EMT and tumor metastasis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26678076,"Year":2016,"Title":"miRNA Isolation from FFPET Specimen: A Technical Comparison of miRNA and Total RNA Isolation Methods.","Abstract":"MiRNA remain stable for detection and PCR-based amplification in FFPE tissue samples. Several miRNA extraction kits are available, however miRNA fraction, as part of total RNA can be isolated using total RNA purification methods, as well. Our primary aim was to compare four different miRNA and total RNA isolation methods from FFPE tissues. Further purposes were to evaluate quantitatively and qualitatively the yield of the isolated miRNA. MiRNAs were isolated from normal colorectal cancer FFPE specimens from the same patients. Two miRNA isolation kits (High Pure miRNA Isolation Kit, miRCURY RNA Isolation Kit) and two total RNA isolation kits were compared (High Pure RNA Paraffin Kit, MagNA Pure 96 Cellular RNA LV Kit). Quantity and quality were determined, expression analysis was performed by real-time PCR using qPCR Human Panel I + II (Exiqon) method detecting 742 human miRNAs in parallel. The yield of total RNA was found to be higher than miRNA purification protocols (in CRC: Ex: 0203 +/- 0021 mug; HPm: 1,45 +/- 0,8 mug; HPp: 21,36 +/- 4,98 mug; MP: 8,6 +/- 5,1 mug). MiRNAs were detected in lower relative quantity of total RNA compared to the miRNA kits. Higher number of miRNAs could be detected by the miRNA isolation kits in comparison to the total RNA isolation methods. (Ex: 497 +/- 16; HPm: 542 +/- 11; HPp: 332 +/- 36; MP: 295 +/- 74). Colon specific miRNAs (miR-21-5p;-34-5p) give satisfying results by miRNA isolation kits. Although miRNA can be detected also after total RNA isolation methods, for reliable and reproducible miRNA expression profiling the use of miRNA isolation kits are more suitable.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26646696,"Year":2016,"Title":"Signature miRNAs in colorectal cancers were revealed using a bias reduction small RNA deep sequencing protocol.","Abstract":"To explore the role of miRNAs in colorectal cancers (CRC), we have deep sequenced 48 pairs of frozen CRC samples, of which 44 pairs produced high quality sequencing data. By using a combined approach of our bias reduction small RNA (smRNA) deep sequencing protocol and Illumina small RNA TruSeq method for sample bar coding, we have obtained data from samples of relatively large size with bias reduced digital profile results. This novel approach allowed us to validate many previously published results using various techniques to profile miRNAs in CRC tissues or cell lines and to characterize 'true' miRNA signatures highly expressed in colon/rectum (CR) or CRC tissues. According to our results, miR-21, a miRNA that is up-regulated in CRC, and miR-143, a miRNA that is down-regulated in CRC, are the two miRNAs that dominated the miRNA population in CR tissues, and probably are also the most important miRNAs in CRCs. These two miRNAs, together with the other eight miRNAs, miR-148a, -194, -192, 200b, -200c, -10b, -26a, and -145, with descending expressing levels, constituted the top 10 highly expressed miRNAs in CR/CRC. Using TaqMan miRNA qPCR, we detected the relative expression of some of the CRC miRNAs in 10 CRC cell lines, validated their dysregulation under cancer condition, and provided possible explanation for their dysregulation, which could be caused by APC, KRAS, or TP53 mutations. We believe these results will provide a new direction in future miRNA-related CRC development studies, and application of miRNAs in CRC diagnosis/prognosis, and therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26523217,"Year":2015,"Title":"Down-regulation of miR-135b in colon adenocarcinoma induced by a TGF-beta receptor I kinase inhibitor (SD-208).","Abstract":"OBJECTIVES: Transforming growth factor-beta (TGF-beta) is involved in colorectal cancer (CRC). The SD-208 acts as an anti-cancer agent in different malignancies via TGF-beta signaling. This work aims to show the effect of manipulation of TGF-beta signaling on some miRNAs implicated in CRC. MATERIALS AND METHODS: We investigated the effects of SD-208 on SW-48, a colon adenocarcinoma cell line. The cell line was treated with 0.5, 1 and 2 muM concentrations of SD-208. Then, the xenograft model of colon cancer was established by subcutaneous inoculation of SW-48 cell line into the nude mice. The animals were treated with SD-208 for three weeks. A quantitative real-time PCR was carried out for expression level analysis of selected oncogenic (miR-21, 31, 20a and 135b) and suppressor-miRNAs (let7-g, miR-133b, 145 and 200c). Data were analyzed using the 2-CT method through student's t-test via the GraphPad Prism software. RESULTS: Our results revealed that SD-208 could significantly down-regulate the expression of one key onco-miRNA, miR-135b, in either SW-48 colon cells (P=0.006) or tumors orthotopically implanted in nude mice (P=0.018). Our in silico study also predicted that SD-208 could modulate the expression of potential downstream tumor suppressor targets of the miR135b. CONCLUSION: Our data provide novel evidence that anticancer effects of SD-208 (and likely other TGF-beta inhibitors) may be owing to their ability to regulate miRNAs expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26503645,"Year":2015,"Title":"Improved synthesis and biological evaluation of Tc-99m radiolabeled AMO for miRNA imaging in tumor xenografts.","Abstract":"MicroRNAs (miRNAs) have been considered as important biomarkers for malignant tumors. In this study, we introduced an improved (99m)Tc labeling method for noninvasive visualization of overexpressed miRNAs in tumor-bearing mice. Anti-miRNA-21 oligonucleotide (AMO) with partial 2'-O-methyl and phosphorothioate modification was designed and chemically synthesized. After conjugated with NHS-MAG3, AMO was labeled with (99m)Tc. Optimization was made to shorten reaction time and to improve labeling efficiency. Labeling efficiency was 97%, and specific activity was 2.78 MBq/ng. During 12 h, (99m)Tc-AMO showed no significant degradation by gel electrophoresis. Its radiochemical purity was stable, between 95.8% and 99.1%. Further, (99m)Tc-AMO decreased the level of miR-21 and increased the expression of PTEN protein at cellular level, shown by qRT-PCR and Western blot. Fluorescent protein labeled AMO displayed specific distribution and good stability in tumor cells. After the administration in tumor-bearing mice, (99m)Tc-AMO showed more radioactive uptake in the miR-21 over-expressed tumors than scramble control. Biodistribution results further proved the significant difference of tumor uptake between (99m)Tc-AMO and (99m)Tc-control. Therefore, this study presents an improved method with shorten time to prepare a (99m)Tc radiolabeled AMO. In addition, it supports the role of (99m)Tc-AMO for noninvasive visualization of miR-21 in malignant tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26465597,"Year":2015,"Title":"microRNA-17 Is the Most Up-Regulated Member of the miR-17-92 Cluster during Early Colon Cancer Evolution.","Abstract":"Deregulated microRNAs play a role in the development and progression of colon cancer, but little is known about their tissue and cell distribution in the continuum of normal mucosa through the premalignant adenoma to invasive adenocarcinoma. The aim of this study was to examine the expression pattern of the miR-17-92 cluster (miR-17, miR-18, miR-19, miR-20 and miR-92) as well as miR-21, miR-31, miR-135b, and miR-145 in early clinically diagnosed colon cancer. MicroRNAs were analysed by chromogenic in situ hybridisation in the normal-adenoma-adenocarcinoma sequence of nine adenocarcinomas developed in mucosal colon polyps. Subsequently, the expression of selected microRNAs was validated in 24 mucosal colon cancer polyps. Expression of miR-17 was confined to the epithelial cells, and the expression levels increased in the transitional zone from normal to adenomatous tissue. The miR-17-92 cluster members, miR-19b, miR-20a, and miR-92a, followed the same expression pattern, but miR-17 was the most predominant. An increased expression of miR-21 was found in the tumour-associated stroma with the most dramatic increase from adenoma to adenocarcinoma, while the number of positive miR-145 fibroblast-like cells in the normal lamina propria (stroma) decreased in a stepwise manner throughout the normal-adenoma-adenocarcinoma sequence. It is concluded that the expression of miR-17, miR-21, and miR-145 changes at early stages of the normal-adenoma-adenocarcinoma sequence. Thus, these microRNAs may play a role in the development of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26462034,"Year":2015,"Title":"Clinical value of integrated-signature miRNAs in colorectal cancer: miRNA expression profiling analysis and experimental validation.","Abstract":"MicroRNA (miRNA) expression profiling of colorectal cancer (CRC) are often inconsistent among different studies. To determine candidate miRNA biomarkers for CRC, we performed an integrative analysis of miRNA expression profiling compared CRC tissues and paired neighboring noncancerous colorectal tissues. Using robust rank aggregation method, we identified a miRNA set of 10 integrated-signature miRNAs. In addition, the qRT-PCR validation demonstrated that 9 miRNAs were consistent dysregulated with the integrative analysis in CRC tissues, 4 miRNAs (miR-21-5p, miR-183-5p, miR-17-5p and miR-20a-5p) were up-regulated expression, and 5 miRNAs (miR-145-5p, miR-195-5p, miR-139-5p, miR-378a-5p and miR-143-3p) were down-regulated expression (all p < 0.05). Consistent with the initial analysis, 7 miRNAs were found to be significantly dysregulated in CRC tissues in TCGA data base, 4 miRNAs (miR-21-5p, miR-183-5p, miR-17-5p and miR-20a-5p) were significantly up-regulated expression, and 3 miRNAs (miR-145-5p, miR-139-5p and miR-378a-5p) were significantly down-regulated expression in CRC tissues (all p < 0.001). Furthermore, miR-17-5p (p = 0.011) and miR-20a-5p (p = 0.003) were up-regulated expression in the III/IV tumor stage, miR-145-5p (p = 0.028) and miR-195-5p (p = 0.001) were significantly increased expression with microscopic vascular invasion in CRC tissues, miR-17-5p (p = 0.037) and miR-145-5p (p = 0.023) were significantly increased expression with lymphovascular invasion. Moreover, Cox regression analysis of CRC patients in TCGA data base showed miR-20a-5p was correlated with survival (hazard ratio: 1.875, 95%CI: 1.088-3.232, p = 0.024). Hence, the finding of current study provides a basic implication of these miRNAs for further clinical application in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26436952,"Year":2015,"Title":"MiR expression profiles of paired primary colorectal cancer and metastases by next-generation sequencing.","Abstract":"MicroRNAs (miRs) have been recognized as promising biomarkers. It is unknown to what extent tumor-derived miRs are differentially expressed between primary colorectal cancers (pCRCs) and metastatic lesions, and to what extent the expression profiles of tumor tissue differ from the surrounding normal tissue. Next-generation sequencing (NGS) of 220 fresh-frozen samples, including paired primary and metastatic tumor tissue and non-tumorous tissue from 38 patients, revealed expression of 2245 known unique mature miRs and 515 novel candidate miRs. Unsupervised clustering of miR expression profiles of pCRC tissue with paired metastases did not separate the two entities, whereas unsupervised clustering of miR expression profiles of pCRC with normal colorectal mucosa demonstrated complete separation of the tumor samples from their paired normal mucosa. Two hundred and twenty-two miRs differentiated both pCRC and metastases from normal tissue samples (false discovery rate (FDR) <0.05). The highest expressed tumor-specific miRs were miR-21 and miR-92a, both previously described to be involved in CRC with potential as circulating biomarker for early detection. Only eight miRs, 0.5% of the analysed miR transcriptome, were differentially expressed between pCRC and the corresponding metastases (FDR <0.1), consisting of five known miRs (miR-320b, miR-320d, miR-3117, miR-1246 and miR-663b) and three novel candidate miRs (chr 1-2552-5p, chr 8-20656-5p and chr 10-25333-3p). These results indicate that previously unrecognized candidate miRs expressed in advanced CRC were identified using NGS. In addition, miR expression profiles of pCRC and metastatic lesions are highly comparable and may be of similar predictive value for prognosis or response to treatment in patients with advanced CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26419959,"Year":2016,"Title":"MicroRNA MIR21 and T Cells in Colorectal Cancer.","Abstract":"The complex interactions between colorectal neoplasia and immune cells in the tumor microenvironment remain to be elucidated. Experimental evidence suggests that microRNA MIR21 (miR-21) suppresses antitumor T-cell-mediated immunity. Thus, we hypothesized that tumor MIR21 expression might be inversely associated with T-cell density in colorectal carcinoma tissue. Using 538 rectal and colon cancer cases from the Nurses' Health Study and the Health Professionals Follow-up Study, we measured tumor MIR21 expression by a quantitative reverse-transcription PCR assay. Densities of CD3(+), CD8(+), CD45RO (PTPRC)(+), and FOXP3(+) cells in tumor tissue were determined by tissue microarray immunohistochemistry and computer-assisted image analysis. Ordinal logistic regression analysis was conducted to assess the association of MIR21 expression (ordinal quartiles as a predictor variable) with T-cell density (ordinal quartiles as an outcome variable), adjusting for tumor molecular features, including microsatellite instability; CpG island methylator phenotype; KRAS, BRAF, and PIK3CA mutations; and LINE-1 methylation. We adjusted the two-sided alpha level to 0.012 for multiple hypothesis testing. Tumor MIR21 expression was inversely associated with densities of CD3(+) and CD45RO(+) cells (Ptrend < 0.0005). The multivariate odds ratio of the highest versus lowest quartile of MIR21 for a unit increase in quartile categories of CD3(+) or CD45RO(+) cells was 0.44 [95% confidence interval (CI), 0.28 to 0.68] or 0.41 (95% CI, 0.26-0.64), respectively. Our data support a possible role of tumor epigenetic deregulation by noncoding RNA in suppressing the antitumor T-cell-mediated adaptive immune response and suggest MIR21 as a potential target for immunotherapy and prevention in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26418978,"Year":2015,"Title":"[Drug resistance of colon cancer cells to 5-fluorouracil mediated by microRNA-21].","Abstract":"OBJECTIVE To explore downstream regulatory pathway of microRNA-21 (miR-21) in colon cancer cells (RKO) through detecting miR-21 and its target PDCD4, and the influence of miR-21 regulation on the sensitivity of RKO cells to 5-fluorouracil (5-FU). METHODS 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the effect of 5-FU on the viability of RKO cells with knockout of miR-21 or high expression of PDCD4. Real-time was used to determine the expression of PDCD4, ABCC5 and CD44 in RKO cell after knockout of miR-21. RESULTS MTT assay reveals that the IC50 of 5-FU in RKO-WT cells (52.82 +/- 0.06 umol/L) was about 67% higher than in miR-21 knockout cells (32.23 +/- 0.05 umol/L) (P < 0.05), and the apoptosis ratio elevated after knockout of miR-21. High expression of PDCD4, a target gene of miR-21, can negatively regulate the expression of ABC transporter ABCC5 and the stem cell marker CD44. CONCLUSION MiR-21 can mediate the drug resistance to 5-FU by inhibiting its target PDCD4, which can regulate the expression of ABCC5 and CD44 genes.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26295583,"Year":2015,"Title":"Genome Wide Expression Profiling of Cancer Cell Lines Cultured in Microgravity Reveals Significant Dysregulation of Cell Cycle and MicroRNA Gene Networks.","Abstract":"Zero gravity causes several changes in metabolic and functional aspects of the human body and experiments in space flight have demonstrated alterations in cancer growth and progression. This study reports the genome wide expression profiling of a colorectal cancer cell line-DLD-1, and a lymphoblast leukemic cell line-MOLT-4, under simulated microgravity in an effort to understand central processes and cellular functions that are dysregulated among both cell lines. Altered cell morphology, reduced cell viability and an aberrant cell cycle profile in comparison to their static controls were observed in both cell lines under microgravity. The process of cell cycle in DLD-1 cells was markedly affected with reduced viability, reduced colony forming ability, an apoptotic population and dysregulation of cell cycle genes, oncogenes, and cancer progression and prognostic markers. DNA microarray analysis revealed 1801 (upregulated) and 2542 (downregulated) genes (>2 fold) in DLD-1 cultures under microgravity while MOLT-4 cultures differentially expressed 349 (upregulated) and 444 (downregulated) genes (>2 fold) under microgravity. The loss in cell proliferative capacity was corroborated with the downregulation of the cell cycle process as demonstrated by functional clustering of DNA microarray data using gene ontology terms. The genome wide expression profile also showed significant dysregulation of post transcriptional gene silencing machinery and multiple microRNA host genes that are potential tumor suppressors and proto-oncogenes including MIR22HG, MIR17HG and MIR21HG. The MIR22HG, a tumor-suppressor gene was one of the highest upregulated genes in the microarray data showing a 4.4 log fold upregulation under microgravity. Real time PCR validated the dysregulation in the host gene by demonstrating a 4.18 log fold upregulation of the miR-22 microRNA. Microarray data also showed dysregulation of direct targets of miR-22, SP1, CDK6 and CCNA2.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26271186,"Year":2015,"Title":"Variability in microRNA recovery from plasma: Comparison of five commercial kits.","Abstract":"Numerous studies have indicated that microRNAs (miRNAs) are present and stable in multiple biological fluids, suggesting a great potential as biomarkers for molecular diagnostics and prognostics. Variations in the amount of starting material and isolation method to obtain miRNA may introduce bias and contribute to quantification errors. Given these concerns, we compared five commercially available kits for serum/plasma miRNA isolation to determine whether the plasma miRNA profile varies with the isolation method. We isolated miRNAs in blood plasma from colorectal cancer patients and healthy donors with five commercially available kits: Exiqon, Norgen, Macherey-Nagel, Qiagen, and Zymo Research. First, we assessed the robustness of the RNA isolation process and the quality of isolated miRNAs with the miRCURY microRNA QC PCR Panel (Exiqon), which contains six RNA spike-ins for quality control of RNA isolation (UniSp2, -4, and -5), complementary DNA (cDNA) synthesis (UniSp6 and cel-miR-39-3p), and polymerase chain reaction (PCR) amplification (UniSp3). This panel also includes circulating human miR-103, miR-191, miR-23a, and miR-451. Second, to evaluate the variability in miRNA profiling in relation to the extraction method, we analyzed plasma levels of candidate miRNA biomarkers for colorectal cancer (miR-18a, miR-21, and miR-29a). To determine PCR efficiencies per amplicon and per sample, we used LinRegPCR software. We found that all isolation methods were suitable for extracting miRNA from plasma samples and that all had similar Cq values in the three steps analyzed: RNA isolation, cDNA synthesis, and quantitative reverse transcription (qRT)-PCR. However, although the PCR replicates were excellent, the intersample variability of the spike-ins was unsatisfactorily high and all kits yielded suboptimal PCR efficiencies for some amplicons. Overall, our results underline the great difficulties involved in measuring miRNAs in plasma. The use of spike-ins is critical to control technical factors that affect final miRNA levels. We recommend that researchers investigating circulating miRNAs verify the PCR efficiency for each amplicon because quantification may be influenced by sample and PCR components.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26250566,"Year":2016,"Title":"Circulating U2 small nuclear RNA fragments as a novel diagnostic biomarker for primary central nervous system lymphoma.","Abstract":"BACKGROUND: Primary central nervous system lymphomas (PCNSLs) are highly aggressive tumors. Chemotherapy has improved prognosis significantly; however, early diagnosis is crucial for effective treatment. Presently, the diagnosis of PCNSL depends on histopathology of tumor biopsies. We have previously demonstrated differential expression of microRNAs in cerebrospinal fluid (CSF) samples from patients with PCNSL. Based on promising findings about circulating U2 small nuclear RNA fragments (RNU2-1f) as novel blood-based biomarkers for pancreatic, colorectal, and lung cancer, we investigated RNU2-1f in the CSF of PCNSL patients. METHODS: CSF was collected from patients with PCNSL (n = 72) and control patients with various neurologic disorders (n = 47). Sequential CSF samples were collected from 9 PCNSL patients. RNU2-1f levels were measured by real-time polymerase chain reaction. RESULTS: Measurement of RNU2-1f levels in CSF enabled the differentiation of patients with PCNSL from controls with an area under the curve (AUC) of 0.909 with a sensitivity of 68.1% and a specificity of 91.4%. The diagnostic accuracy was further improved by combined determination of RNU2-1f and miR-21, resulting in AUC of 0.987 with a sensitivity of 91.7% and a specificity of 95.7%. In consecutive measurements of RNU2-1f, which were performed in 9 patients at different stages of the disease course, RNU2-1f CSF levels paralleled the course of the disease. CONCLUSIONS: Our data suggest that the measurement of RNU2-1f detected in CSF can be used as a diagnostic marker and also as a possible marker for treatment monitoring. These promising results need to be evaluated within a larger patient cohort.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26193421,"Year":2015,"Title":"The S100P/RAGE signaling pathway regulates expression of microRNA-21 in colon cancer cells.","Abstract":"S100P signaling through the receptor for advanced glycation end-products (RAGE) contributes to colon cancer invasion and metastasis, but the mechanistic features of this process are obscure. Here, we investigate whether activation of S100P/RAGE signaling regulates oncogenic microRNA-21 (miR-21). We show that exogenous S100P up-regulates miR-21 levels in human colon cancer cells, whereas knockdown of S100P results in a decrease of miR-21. Furthermore, blockage of RAGE with anti-RAGE antibody suppresses S100P induction of miR-21. In addition, we found that S100P induction of miR-21 expression involves ERK and is suppressed by the MEK inhibitor U0126. Also, S100P treatment stimulates the enrichment of c-Fos, and AP-1 family members, at the miR-21 gene promoter.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26184038,"Year":2015,"Title":"IL6 Mediates Immune and Colorectal Cancer Cell Cross-talk via miR-21 and miR-29b.","Abstract":"UNLABELLED: Tumors are surrounded and infiltrated by a variety of stromal cell types, including fibroblasts, immune cells, and vascular endothelial cells, which interact with malignant cells to generate the tumor microenvironment (TME). This complex environment is thought to be regulated by the tumor in order to promote its survival and progression and thus constitutes a potential target for cancer therapy. However, intercellular communication within the microenvironment is not yet well understood. The current study investigates the mechanism by which cancer and immune cells communicate using an in vitro coculture model. It is demonstrated that IL6, a proinflammatory cytokine, secreted by immune cells promotes colorectal cancer cell invasiveness. In addition, in the presence of IL6, the cancer cells were able to secrete circulating miRNAs miR-21 and miR-29b to further induce immune cell IL6 production. Activated immune cells were also found to release miR-21 into the TME. Taken together, these mechanistic findings provide a better understanding of intercellular communication between immune and cancer cells in the TME and offer insight into some of the key players that mediate this cross-talk. IMPLICATIONS: This study demonstrates that cocultured cancer and immune cells communicate via IL6 and circulating miRNAs to sustain chronic inflammation and promote prometastatic cancer cell behavior. In addition, critical players are identified that mediate intercellular communication in the TME and suggest possible therapeutic approaches that target the microenvironment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26038573,"Year":2015,"Title":"Serum miR-21, miR-29a, and miR-125b Are Promising Biomarkers for the Early Detection of Colorectal Neoplasia.","Abstract":"PURPOSE: Circulating microRNAs (miRNA) are emerging as promising diagnostic biomarkers for colorectal cancer, but their usefulness for detecting early colorectal neoplasms remains unclear. This study aimed to identify serum miRNA biomarkers for the identification of patients with early colorectal neoplasms. EXPERIMENTAL DESIGN: A cohort of 237 serum samples from 160 patients with early colorectal neoplasms (148 precancerous lesions and 12 cancers) and 77 healthy subjects was analyzed in a three-step approach that included a comprehensive literature review for published biomarkers, a screening phase, and a validation phase. RNA was extracted from sera, and levels of miRNAs were examined by real-time RT-PCR. RESULTS: Nine miRNAs (miR-18a, miR-19a, miR-19b, miR-20a, miR-21, miR-24, miR-29a, miR-92, and miR-125b) were selected as candidate biomarkers for initial analysis. In the screening phase, serum levels of miR-21, miR-29a, and miR-125b were significantly higher in patients with early colorectal neoplasm than in healthy controls. Elevated levels of miR-21, miR-29a, and miR-125b were confirmed in the validation phase using an independent set of subjects. Area under the curve (AUC) values for serum miR-21, miR-29a, miR-125b, and their combined score in discriminating patients with early colorectal neoplasm from healthy controls were 0.706, 0.741, 0.806, and 0.827, respectively. Serum levels of miR-29a and miR-125b were significantly higher in patients who had only small colorectal neoplasms (<\/=5 mm) than in healthy subjects. CONCLUSIONS: Because serum levels of miR-21, miR-29a, and miR-125b discriminated patients with early colorectal neoplasm from healthy controls, our data highlight the potential clinical use of these molecular signatures for noninvasive screening of patients with colorectal neoplasia.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26036630,"Year":2015,"Title":"Absolute quantification of cell-free microRNAs in cancer patients.","Abstract":"The hypothesis to use microRNAs (miRNAs) circulating in the blood as cancer biomarkers was formulated some years ago based on promising initial results. After some exciting discoveries, however, it became evident that the accurate quantification of cell-free miRNAs was more challenging than expected. Difficulties were linked to the strong impact that many, if not all, pre- and post- analytical variables have on the final results. In this study, we used currently available high-throughput technologies to identify miRNAs present in plasma and serum of patients with breast, colorectal, lung, thyroid and melanoma tumors, and healthy controls. Then, we assessed the absolute level of nine different miRNAs (miR-320a, miR-21-5p, miR-378a-3p, miR-181a-5p, miR-3156-5p, miR-2110, miR-125a-5p, miR-425-5p, miR-766-3p) in 207 samples from healthy controls and cancer patients using droplet digital PCR (ddPCR) technology. We identified miRNAs specifically modulated in one or more cancer types, according to tissue source. The significant reduction of miR-181a-5p levels in breast cancer patients serum was further validated using two independent cohorts, one from Italy (n = 70) and one from US (n = 90), with AUC 0.66 and 0.73 respectively. This study finally powers the use of cell-free miRNAs as cancer biomarkers and propose miR-181a-5p as a diagnostic breast cancer biomarker.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25994220,"Year":2016,"Title":"Novel evidence for an oncogenic role of microRNA-21 in colitis-associated colorectal cancer.","Abstract":"OBJECTIVE: miR-21 was found to be overexpressed in the colon tissues and serum of patients with UC and colorectal cancer (CRC); however, the exact roles of miR-21 in colitis-associated CRC remain unclear. The aim of our study was to investigate the biological mechanisms of miR-21 in colitis-associated colon cancer (CAC). DESIGN: miR-21 expression was examined in the tumours of 62 patients with CRC from China and 37 colitis-associated neoplastic tissues from Japan and Austria. The biological functions of miR-21 were studied using a series of in vitro, in vivo and clinical approaches. RESULTS: miR-21 levels were markedly upregulated in the tumours of 62 patients with CRC, 22 patients with CAC, and in a mouse model of CAC. Following azoxymethane and dextran sulfate sodium intervention, miR-21-knockout mice showed reduced expression of proinflammatory and procarcinogenic cytokines (interleukin (IL) 6, IL-23, IL-17A and IL-21) and a decrease in the size and number of tumours compared with the control mouse group. The absence of miR-21 resulted in the reduced expression of Ki67 and the attenuated proliferation of tumour cells with a simultaneous increase in E-cadherin and decrease in beta-catenin and SOX9 in the tumours of CAC mice. Furthermore, the absence of miR-21 increased the expression of its target gene PDCD4 and subsequently modulated nuclear factor (NF)-kappaB activation. Meanwhile, miR-21 loss reduced STAT3 and Bcl-2 activation, causing an increase in the apoptosis of tumour cells in CAC mice. CONCLUSIONS: These observations provide novel evidence for miR-21 blockade to be a key strategy in reducing CAC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25989926,"Year":2015,"Title":"Fecal microRNA profile in patients with colorectal carcinoma before and after curative surgery.","Abstract":"PURPOSE: The purpose of this study was to explore the potential role of deranged fecal microRNA (miRNA) pattern as a reliable warning signal of colorectal cancer (CRC), a subset of fecal CRC-related miRNAs was evaluated in CRC patients, before and after surgery, and in healthy controls. METHODS: Twenty CRC patients and 20 age/sex-matched healthy volunteers with negative colonoscopy entered the study. Cancer biopsy, colonic mucosa from the resected specimens, and fecal samples from patients and controls were screened for 13 miRNAs involved in CRC onset and progressions by reverse transcription quantitative PCR (RT-qPCR). Postoperative evaluation of fecal miRNAs was carried out after a median follow-up of 18 months (range 12-30). RESULTS: Two out 13 miRNAs (RNU6B, miR-16-3p) were used as internal controls leaving 11 available for analysis. Cancer tissue contained significantly higher expression of all miRNAs, compared to normal mucosa (p < 0.05). Expression of preoperative levels of five fecal miRNAs, (miR-19-b-3p, miR-20a-5p, miR-21-3p, miR92a-3p, miR141) was significantly higher in CRC patients compared to controls and significantly decreased after curative surgery. Three out of these five miRNAs (miR20a-5p, miR21-3p, and miR141) returned to values comparable to normal controls. CONCLUSIONS: A set of three specific fecal miRNAs is overexpressed before surgery, and return within the normal range after cancer removal could be considered as an appealing opportunity for a new reliable tool for CRC secondary prevention. However, their role needs to be explored in large prospective trials and compared with the existing screening tools.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25953218,"Year":2015,"Title":"MicroRNA-21 predicts response to preoperative chemoradiotherapy in locally advanced rectal cancer.","Abstract":"PURPOSE: The treatment of choice for locally advanced rectal cancer is preoperative chemoradiotherapy. Despite half of patients do not respond and suffer unnecessary toxicities and surgery delays, there are no biomarkers to guide preoperative CRT outcome. MicroRNA-21 has been related to acquisition of 5-fluorouracil resistance; however, its potential predictive value of response to preoperative chemoradiotherapy in locally advanced rectal cancer remains unknown. METHODS: Nighty-two patients diagnosed with locally advanced rectal cancer who were preoperatively treated with chemoradiotherapy were selected for this study. Moreover, microRNA-21 expression was quantified in formalin-fixed paraffin-embedded biopsies from this cohort, and the results obtained were correlated with clinical and molecular characteristics, pathological response, and outcome. RESULTS: MicroRNA-21 was found overexpressed in 77.6% cases, and significantly correlated with tumor grade after preoperative chemoradiotherapy (P = 0.013) and with pathological response (P = 0.013). The odds ratio of having miR-21 overexpression and not getting a respond to chemoradiotherapy resulted in 9.75 CI 2.24 to 42. Sensitivity, specificity, negative predictive values, and positive predictive value were 86.6, 60, 42.8, and 92%, respectively. Multivariate analysis confirmed the clinical significance of miR-21 determining preoperative chemoradiotherapy response. CONCLUSIONS: MicroRNA-21 expression efficiently predicts preoperative chemoradiotherapy pathological response in locally advanced rectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25928322,"Year":2015,"Title":"miR-21 and miR-145 cooperation in regulation of colon cancer stem cells.","Abstract":"BACKGROUND: Acquired drug resistance is one of the major reasons for failing cancer therapies. Although the reasons are not fully understood, they may be related to the presence of cancer stem cells (CSCs). We have reported that chemo-resistant (CR) colon cancer cells, highly enriched in CSCs, exhibit a marked up-regulation of miR-21 and that down-regulation of this miR renders the CR cells more susceptible to therapeutic regimens. However, the underlying molecular mechanism is poorly understood. The aim of this investigation is to unravel this mechanism. METHODS: The levels of miR-145 and miR-21 were manipulated by transfection of mature, antago-miRs or pCMV/miR-145 expression plasmid. Quantitative RT-PCR or/and Western blots were performed to examine the expression of CD44, beta-catenin, Sox-2, PDCD4, CK-20 and k-Ras. Colonosphere formation and SCID mice xenograft studies were performed to evaluate the tumorigenic properties of CSC-enriched colon CR cells. RESULTS: We investigated the role that microRNAs (miRs), specifically miR-21 and miR-145 play in regulating colon CSCs. We found the expression of miR-21 to be greatly increased and miR-145 decreased in CR colon cancer cells that are highly enriched in CSC, indicating a role for these miRNAs in regulating CSCs. In support of this, we found that whereas forced expression of miR-145 in colon cancer cells greatly inhibits CSCs and tumor growth, up-regulation of miR-21 causes an opposite phenomenon. In addition, administration of mature miR-145 or antagomir-21 (anti-sense miR-21) greatly suppresses the growth of colon cancer cell xenografts in SCID mice. This was associated with decreased expression of CD44, beta-catenin, Sox-2 and induction of CK-20 indicating that administration of miR-145 or antagomir-21 decreases CSC proliferation and induces differentiation. In vitro studies further demonstrate that miR-21 negatively regulates miR-145 and vice versa. k-Ras appears to play critical role in regulation of this process, as evidenced by the fact that the absence of k-Ras in CR colon cancer cells increases miR-145 expression, suppresses miR-21, and interrupts the negative cooperation between miR-21 and miR-145. CONCLUSIONS: Our current observations suggest that miR-21, miR-145, and their networks play critical roles in regulating CSCs growth and/or differentiation in the colon cancer and progression of chemo-resistance.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25925209,"Year":2015,"Title":"Differential expressions of cancer-associated genes and their regulatory miRNAs in colorectal carcinoma.","Abstract":"Colorectal cancer is one of the frequently seen malignancies in the world. To date, several oncogenes and tumor suppressor genes have been identified and linked to colorectal cancer pathogenesis. Although recent advances in the diagnosis and therapy of colorectal cancer are promising, identifying novel genetic contributors is still high priority. In the present study, expression profile of some cancer-related genes and their regulatory miRNA molecules were evaluated by using a high-throughput real-time PCR method. For the study, a total of 54 patients diagnosed with CRC and normal colon tissue samples of 42 healthy controls were included. For the expression analysis, total RNA was extracted from FFPE tissue samples and converted to cDNA. All expression analyses were assessed by using Fluidigm Microfluidic Dynamic Array chips for 96 samples and the reactions were held in Fluidigm BioMark HD System Real-Time PCR. As a result of the study, expression of the ADAMTS1, FHIT, RUNX1, RUNX3 and WWOX genes was shown to be significantly altered in CRC tissues in contrast to normal tissue samples. Moreover, miR-378a-3p, miR-155-5p, miR-193b-3p, miR-96-5p, miR-17-5p, miR-27a-3p, miR-133b, miR-203a, miR-205-5p, miR-34c-5p, miR-130a-3p, miR-301a-3p, miR-132-3p, miR-222-3p, miR-34a-5p, miR-21-5p, miR-29a-3p and miR-29b-3p were found to be significantly deregulated in CRC. Consequently, results of the current study strongly suggest the involvement of novel cancer-related genes and their regulatory miRNAs in CRC physiopathology.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25856691,"Year":2015,"Title":"The role of circulating microRNAs as novel biomarkers in diagnosing colorectal cancer: a meta-analysis.","Abstract":"OBJECTIVES: Several microRNAs (miRNAs) have been identified as potential circulating biomarkers in a number of different cancers including colorectal cancer (CRC). This study aims to assess the diagnostic performance of circulating miRNAs in detecting CRC through meta-analysis of all eligible relevant studies. MATERIALS AND METHODS: An extensive literature search was performed and studies that estimated the diagnostic accuracy of miRNAs in CRC were identified. Data from the eligible studies were collected and pooled; sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratios, weighted symmetric summary ROC curve and the area under the curve (AUC) were calculated. Heterogeneity was evaluated using the Q-test and I(2)-statistics. In addition, subgroup analyses and meta-regression analyses were carried out to explore the potential sources of significant heterogeneity. RESULTS: A total of 16 studies were included in the meta-analysis according to the inclusion criteria. The overall analysis showed that circulating miRNAs have a relatively good diagnostic performance in CRC, with a sensitivity of 78%, a specificity of 79% and an AUC of 0.87. Subgroup analyses showed that a single miRNA-21 test, as opposed to a panel miRNAs test, significantly improved the diagnostic accuracy with 83.4% sensitivity, 91.6% specificity, and AUC increasing to 0.94. CONCLUSION: Circulating miRNAs, especially miRNA-21, are promising diagnostic biomarkers in CRC. However, more prospective studies are required to further explore their diagnostic role and their usefulness in clinical practice.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25788261,"Year":2015,"Title":"Stratifying risk of recurrence in stage II colorectal cancer using deregulated stromal and epithelial microRNAs.","Abstract":"MicroRNAs (miRNAs) enable colonic epithelial cells to acquire malignant characteristics and metastatic capabilities. Recently, cancer relevant miRNAs deregulated during disease progression have also been identified in tumor-associated stroma.By combining laser-microdissection (LMD) with high-throughput screening and high-sensitivity quantitation techniques, miRNA expression in colorectal cancer (CRC) specimens and paired normal colonic tissue was independently characterized in stromal and epithelial tissue compartments. Notably, deregulation of the key oncogene miR-21 was identified exclusively as a stromal phenomenon and miR-106a, an epithelial phenomenon in the malignant state.MiRNAs identified in this study successfully distinguished CRC from normal tissue and metastatic from non-metastatic tumor specimens. Furthermore, in a separate cohort of 50 consecutive patients with CRC, stromal miR-21 and miR-556 and epithelial miR-106a expression predicted short disease free survival (DFS) and overall survival (OS) in stage II disease: miR-21 (DFS: HR = 2.68, p = 0.015; OS: HR = 2.47, p = 0.029); miR-556 (DFS: HR = 2.60, p = 0.018); miR-106a (DFS: HR = 2.91, p = 0.008; OS: HR = 2.25, p = 0.049); combined (All High vs. All Low. DFS: HR = 5.83, p = 0.002; OS: HR = 4.13, p = 0.007).These data support the notion that stromal as well as epithelial miRNAs play important roles during disease progression, and that mapping patterns of deregulated gene expression to the appropriate tumor strata may be a valuable aid to therapeutic decision making in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25773836,"Year":2015,"Title":"MicroRNA expression profile in patients with stage II colorectal cancer: a Turkish referral center study.","Abstract":"BACKGROUND: There are increasing data about microRNAs (miRNA) in the literature, providing abundant evidence that they play important roles in pathogenesis and development of colorectal cancer. In this study, we aimed to investigate the miRNA expression profiles in surgically resected specimens of patients with recurrent and non-recurrent colorectal cancer. MATERIALS AND METHODS: The study population included 40 patients with stage II colorectal cancer (20 patients with recurrent tumors, and 20 sex and age matched patients without recurrence), who underwent curative colectomy between 2004 and 2011 without adjuvant therapy. Expression of 16 miRNAs (miRNA-9, 21, 30d, 31, 106a, 127, 133a, 133b, 135b, 143, 145, 155, 182, 200a, 200c, 362) was verified by quantitative real-time polymerase chain reaction (qRT-PCR) in all resected colon cancer tissue samples and in corresponding normal colonic tissues. Data analyses were carried out using SPSS 15 software. Values were statistically significantly changed in 40 cancer tissues when compared to the corresponding 40 normal colonic tissues (p<0.001). MiR-30d, miR-133a, miR-143, miR-145 and miR-362 expression was statistically significantly downregulated in 40 resected colorectal cancer tissue samples (p<0.001). When we compared subgroups, miRNA expression profiles of 20 recurrent cancer tissues were similar to all 40 cancer tissues. However in 20 non-recurrent cancer tissues, miR-133a expression was not significantly downregulated, moreover miR-133b expression was significantly upregulated (p<0.05). CONCLUSIONS: Our study revealed dysregulation of expression of ten miRNAs in Turkish colon cancer patients. These miRNAs may be used as potential biomarkers for early detection, screening and surveillance of colorectal cancer, with functional effects on tumor cell behavior.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25663768,"Year":2015,"Title":"MiR-21/RASA1 axis affects malignancy of colon cancer cells via RAS pathways.","Abstract":"AIM: To determine how the oncogene miR-21 regulates the RAS signaling pathways and affects colon cancer cell behaviors. METHODS: RAS p21 GTPase activating protein 1 (RASA1) protein expression in six colon cancer cell lines was assessed by Western blot. Colon cancer RKO cells were chosen for transfection because they are KRAS wild type colon cancer cells whose RASA1 expression is significantly decreased. RKO cells were transfected with vectors overexpressing or down-regulating either miR-21 or RASA1. Furthermore, a luciferase reporter assay was used to determine whether RASA1 is a gene target of miR-21. Then, changes in mRNA and protein levels of RASA1, RAS-GTP, and other components of the RAS signaling pathways were assessed in transfected RKO cells by real-time quantitative reverse transcription-polymerase chain reaction, Western blot and immunoprecipitation. Finally, cell proliferation, apoptosis, invasion, and tumor formation ability were assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide dye assay, flow cytometry, transwell assay, and animal experiment, respectively. RESULTS: RASA1 protein levels were significantly decreased in RKO cells compared with the other 5 colon cancer cell lines, and RASA1 was confirmed as a target gene of miR-21. Interestingly, RASA1 mRNA and protein levels in pre-miR-21-LV (up-regulation of miR-21) cells were lower than those in anti-miR-21-LV (down-regulation of miR-21) cells (P < 0.05). In addition, pre-miR-21-LV or siRASA1 (down-regulation of RASA1) cells showed higher cell proliferation, reduced apoptosis, increased expression of RAS-GTP, p-AKT, Raf-1, KRAS, and p-ERK1/2, and higher invasion and tumor formation ability, compared with control, anti-miR-21-LV or pcDNA3.1-RASA1 (up-regulation of RASA1) cells (P < 0.05). CONCLUSION: RASA1 is a target gene of miR-21, which promotes malignant behaviors of RKO cells through regulation of RASA1 expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25603978,"Year":2015,"Title":"MicroRNA-21 controls hTERT via PTEN in human colorectal cancer cell proliferation.","Abstract":"Colorectal cancer is a major health problem worldwide. The aim of this study was to determine a role of microRNA-21 (miRNA-21) in colorectal cancer (CRC) and to elucidate miRNA-21 regulation of hTERT by phosphatase and tensin homologue (PTEN). Protein and mRNA samples were extracted with 30 CRC samples and one CRC cell lines. The expression of miRNA-21, hTERT, PTEN in CRC tissues and CRC cell lines was measured by real-time fluorescent quantitative PCR, Western blotting. Cell viability was detected by MTT and cell cycle assay. In this study, we show that the expression of miRNA-21 was overexpressed in CRC tissue and CRC cell lines compared with the control group. The effects of miRNA-21 were then assessed in MTT assays through in vitro transfection with a miRNA-21 mimic or inhibitor. PTEN has been identified as a target gene of miRNA-21 in CRC cell lines. Moreover, Western blot and qRT-PCR analyses revealed that miRNA-21 increased the expression of human telomerase reverse transcriptase (hTERT) via the PTEN/ERK1/2. In addition, Western blot analyses confirmed that an inverse correlation between PTEN and hTERT levels of high miRNA-21 RNA-expressing CRC tissues and cell lines. Finally, these data indicate that miRNA-21 regulates hTERT expression via the PTEN/ERK1/2 signaling pathway, therefore controlling CRC cell line growth. MiRNA-21 may serve as a novel therapeutic target in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25586944,"Year":2015,"Title":"MicroRNA and targeted mRNA expression profiling analysis in human colorectal adenomas and adenocarcinomas.","Abstract":"BACKGROUND: Colorectal cancer (CRC) mainly develops from colorectal adenomas (CRAs). MicroRNAs (miRs) are short non-coding transcripts that regulate gene expression by binding to target mRNAs, preventing their expression. It was suggested that miRs were involved in cancer as tumour suppressors or oncogenes, thereby being also potential cancer biomarkers. We conducted an expression analysis of miRNAs and several of their target mRNAs, by using microarrays and quantitative Reverse Transcription-Polymerase Chain Reaction (RT-PCR) (RT-qPCR), in CRA and CRC, as compared to normal mucosa (NOR), in order to identify candidate miRNAs involved in CRC progression. RESULTS: Microarray, together with confirmatory RT-qPCR analyses, showed 17 significantly deregulated miRNAs in colorectal lesions. While, as expected, some miRNAs have been previously reported to be associated with CRC, including miR-21 and miR-145, others were new (miR-125a-5p and miR-320 family). Some miRNAs were specific for the CRC versus NOR comparison (miR-320b), or for the CRA versus NOR comparison (miR-15b or miR-16), but several of them (miR-21, miR-24, miR-145, mir-150, miR-378) were deregulated in both CRAs and CRCs, as compared to NOR. The impact of these changes in miR expression on target genes is suggested by the associated deregulation of these genes in CRA and CRC. CONCLUSIONS: We confirmed that several miRNAs were abnormally expressed in colorectal lesions, identified new deregulated miRs, and showed that several miRNAs could mark the transition from NOR to CRA, thereby marking progression from the early steps of cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25584614,"Year":2015,"Title":"Relationship between expression of onco-related miRNAs and the endoscopic appearance of colorectal tumors.","Abstract":"Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25569638,"Year":2015,"Title":"Differential MIR-21 expression in plasma from mesenteric versus peripheral veins: an observational study of disease-free survival in surgically resected colon cancer patients.","Abstract":"Findings on the role of plasma miR-21 expression in colorectal cancer are contradictory. Before reaching a peripheral vein (PV), microRNAs released by the tumor are dispersed throughout the body. We hypothesized that blood drawn from the mesenteric vein (MV) near the site of the primary tumor could provide more homogeneous information than blood drawn from the PV.We have analyzed miR-21 expression in matched samples of tumor tissue, normal tissue, MV plasma, and PV plasma in 57 surgically resected patients with colon cancer and correlated our findings with clinical characteristics and disease-free survival (DFS).miR-21 expression was higher in MV than PV plasma (P = 0.014) and in tumor than in normal tissue (P < 0.001). Patients with high levels of miR-21 in MV plasma had shorter DFS (P = 0.05) than those with low levels, and those with high levels in both MV and PV plasma had shorter DFS than all other patients (P = 0.01).Our findings suggest that the primary tumor in colon cancer releases high concentrations of miR-21 in the MV but that these concentrations are later diluted in the circulatory system. MV expression of miR-21 may be a stronger prognostic marker than PV expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25497975,"Year":2015,"Title":"Five functional polymorphisms of B7/CD28 co-signaling molecules alter susceptibility to colorectal cancer.","Abstract":"Polymorphisms within the 3'-untranslated region (3'-UTR) of genes have been proved to contribute to the risk of cancers. Here, we determined 16 putatively functional polymorphisms in the 3'-UTR of 11 B7/CD28 genes in 382 colorectal cancer patients and 714 healthy controls. Statistical analysis revealed that ICOS rs4404254-C-allele carriers (p=0.0014), rs1559931-A-allele carriers (p=0.0027), and rs4675379-C-allele carriers (p=0.026) were significantly fewer in patients than those in controls. B7-H4-rs13505-GG homozygotes were more prevalent in patients (p=0.03). CD80-rs7628626-GT was apparently less in the patients with lymph node metastasis (p=0.004) or in advanced stage (p=0.037). Furthermore, we found that these polymorphisms impacted the regulatory role of miR-21-3p, miR-186-5p, miR-323b-5p, miR-1207-5p, miR-1279, miR-2117, and miR-3692-3p in the expression of the B7/CD28 molecules. Our findings suggest that rs7628626, rs13505, rs4404254, rs1559931, and rs4675379, through disrupting the regulatory role of miRNAs in the expression of B7/CD28 molecules, contribute to the occurrence and progress of colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25496125,"Year":2014,"Title":"Overexpression of miR-21-5p as a predictive marker for complete tumor regression to neoadjuvant chemoradiotherapy in rectal cancer patients.","Abstract":"BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) followed by radical surgery is the preferred treatment strategy for locally advanced rectal cancer. However, complete tumor regression is observed in a significant proportion of patients after nCRT, making them ideal candidates for alternative treatment strategies to this considerably morbid procedure. Identification of such patients based on clinical findings (complete clinical response - cCR) is difficult mainly because it relies on subjective clinical and imaging studies. Our goal was to identify biomarkers capable of predicting complete response to nCRT. METHODS: We analyzed miRNA expression profile using deep sequencing in rectal tumor biopsies prior to nCRT. Differential expression was investigated by EdgeR for a training (n = 27) and a validation (n = 16) set of patients to identify miRNAs associated with treatment response (complete vs. incomplete). In vitro experiments with two cancer cell lines were also performed in order to evaluate the possible role of miRNAs on response to nCRT. RESULTS: We found 4 miRNAs differentially expressed between complete and incomplete responders to nCRT. In addition, validation was performed using an independent group of patients and miR-21-5p was confirmed as being overexpressed in complete responders. Overall sensitivity and specificity of miR-21-5p expression in predicting complete response to nCRT was 78% and 86% respectively. Interestingly, in a subset of patients with cCR followed by early local recurrence, the expression level of miR-21-5p was considerably low, similarly to incomplete responders. We also found SATB1, a miR-21-5p target gene and known multidrug resistance gene, whose expression was inversely correlated with miR-21-5p expression. Finally, we performed functional experiments and showed that miR-21-5p and SATB1 may be directly involved with poor response to nCRT in rectal cancer patients. CONCLUSIONS: This study suggests miR-21-5p as a promising predictive biomarker, which should aid in the selection of patients with cCR to nCRT that potentially could be spared from radical surgery.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25446261,"Year":2015,"Title":"Long non-coding RNA CASC2 suppresses malignancy in human gliomas by miR-21.","Abstract":"Long non-coding RNAs (lncRNAs) are aberrantly expressed in many diseases including cancer. LncRNA CASC2 (cancer susceptibility candidate 2) has been characterized as a tumor suppressor in endometrial cancer and colorectal cancer. However, the role and function of CASC2 in human gliomas remain unknown. In this study, we confirmed that CASC2 was lowly expressed in glioma tissues as well as in U251 and U87 glioma cell lines. Overexpression of CASC2 inhibited the malignancy of glioma cells, including proliferation, migration, and invasion, and promoted cell apoptosis. MicroRNA-21 (miR-21) has been reported to be overexpressed in human glioma tissues and cell lines, which is responsible for the malignant progression of glioma. We found that up-regulated CASC2 decreased the expression of miR-21 significantly and there is a reciprocal repression between CASC2 and miR-21 in an Argonaute2-dependent manner. Furthermore, bioinformatics, luciferase reporter assays and pull-down assay confirmed that miR-21 binds to CASC2 in a sequence-specific manner. Introduction of miR-21 largely abrogated CASC2-mediated inhibition of glioma cell proliferation, migration, and invasion, and promotion of cell apoptosis. This study demonstrated that CASC2 plays a tumor suppressive role in glioma via negative regulation of miR-21, which may be a novel therapeutic target for treating gliomas.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25421755,"Year":2015,"Title":"Clinical significance of microRNA-21 as a biomarker in each Dukes' stage of colorectal cancer.","Abstract":"The potential value of microRNAs (miRNAs) as prognostic biomarkers are of interest. It is known that microRNA-21 (miR-21) is implicated in the promotion, proliferation and progression of several types of human cancers. However, the prognostic significance of miR-21 in each tumor stage of colorectal cancer (CRC) remains elusive. The objective of this study was to clarify the prognostic value of miR-21 for CRC patients at each tumor stage. The expression levels of miR-21 in the tumor tissues and normal adjacent tumor tissues of 306 CRC patients were determined by TaqMan microRNA assays. In order to clarify the miRNA profile in CRC tissues, miRNA arrays were examined. In this analysis, miR-21, miR-224, miR-96, miR-31 and miR-155 showed marked upregulation, and miR-21 showed the highest level. Upon comparison of clinicopathological factors, miR-21 expression showed significant association with depth of invasion, lymphatic and venous invasion, liver metastasis and Dukes' stage. In the Kaplan-Meier survival curve analysis of all patients, overall survival (OS) and disease-free survival (DFS) rates of the patients with high miR-21 expression were significantly worse than these rates in patients with low miR-21 expression. In the Kaplan-Meier analysis of each tumor stage, the DFS of patients with high miR-21 expression was significantly worse than patients with low miR-21 levels in Dukes' stage A tumors. In Dukes' stage B and C, patients with high miR-21 expression showed a significantly worse OS and DFS than patients with low miR-21 expression. In Dukes' stage D, patients with high miR-21 expression showed a significantly worse OS than patients with low miR-21 expression. In the Cox multivariate analysis, it was shown that miR-21 expressions in CRC tissues is an independent prognostic factor in Dukes' stage B, C and D. In conclusion, miR-21 expression may be a valuable biomarker for prediction of poor prognosis in CRC patients with Dukes' stage B, C and D.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25405754,"Year":2014,"Title":"Technical factors involved in the measurement of circulating microRNA biomarkers for the detection of colorectal neoplasia.","Abstract":"BACKGROUND: Circulating miRNAs are emerging as promising blood-based biomarkers for colorectal and other human cancers; however, technical factors that confound the development of these assays remain poorly understood and present a clinical challenge. The aim of this study was to systematically evaluate the effects of factors that may interfere with the accurate measurement of circulating miRNAs for clinical purposes. METHODS: Blood samples from 53 subjects, including routinely drawn serum samples, matched plasma from 30 subjects, and matched serum samples drawn before and after bowel preparation for colonoscopy from 29 subjects were collected. Additionally, 38 serum specimens stored in the clinical laboratory for seven days were used to test the stability of miRNAs. Hemolysis controls with serial dilutions of hemoglobin were prepared. RNA was extracted from serum, plasma or hemolyzed controls with spiked-in cel-miR-39, and levels of miR-21, miR-29a, miR-125b and miR-16 were examined by real-time RT-PCR. Hemolysis was measured by spectrophotometry. RESULTS: The expression levels of miR-16 and the degree of hemolysis were significantly higher in plasma than in serum (P<0.0001). Measured miR-21, miR-29a, miR-125b and miR-16 expression increased with hemoglobin levels in hemolyzed controls. The degree of hemolysis in serum samples correlated significantly with the levels of miR-21 (P<0.0001), miR-29a (P = 0.0002), miR-125b (P<0.0001) and miR-16 (P<0.0001). All four miRNAs showed significantly lower levels in sera that had been stored at 4 degrees C for seven days (P<0.0001). Levels of miR-21 (P<0.0001), miR-29a (P<0.0001) and miR-16 (P = 0.0003), and the degree of hemolysis (P = 0.0002) were significantly higher in sera drawn after vs. before bowel preparation. CONCLUSIONS: The measured levels of miRNAs in serum and plasma from same patients varied in the presence of hemolysis, and since hemolysis and other factors affected miRNA expression, it is important to consider these confounders while developing miRNA-based diagnostic assays.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25310697,"Year":2014,"Title":"Inflammation and MiR-21 pathways functionally interact to downregulate PDCD4 in colorectal cancer.","Abstract":"Inflammation plays a direct role in colorectal cancer (CRC) progression; however the molecular mechanisms responsible for this effect are unclear. The inflammation induced cyclooxygenase 2 (COX-2) enzyme required for the production of Prostaglandin E2 (PGE2), can promote colorectal cancer by decreasing expression of the tumour suppressor gene Programmed Cell Death 4 (PDCD4). As PDCD4 is also a direct target of the oncogene microRNA-21 (miR-21) we investigated the relationship between the COX-2 and miR-21 pathways in colorectal cancer progression. Gene expression profile in tumour and paired normal mucosa from 45 CRC patients demonstrated that up-regulation of COX-2 and miR-21 in tumour tissue correlates with worse Dukes' stage. In vitro studies in colonic adenocarcinoma cells revealed that treatment with the selective COX-2 inhibitor NS398 significantly decreased miR-21 levels (p = 0.0067) and increased PDCD4 protein levels (p<0.001), whilst treatment with PGE2 up-regulated miR-21 expression (p = 0.019) and down-regulated PDCD4 protein (p<0.05). These findings indicate that miR-21 is a component of the COX-2 inflammation pathway and that this pathway promotes worsening of disease stage in colorectal cancer by inducing accumulation of PGE2 and increasing expression of miR-21 with consequent downregulation of the tumour suppressor gene PDCD4.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25292032,"Year":2014,"Title":"Detection of microRNA-21 expression as a potential screening biomarker for colorectal cancer: a meta-analysis.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is a major cause of cancer-related death and cancer-related incidence worldwide. The potential of microRNA-21 (miR-21) as a biomarker for CRC detection has been studied in several studies. However, the results were inconsistent. Therefore, we conducted the present meta-analysis to systematically assess the diagnostic value of miR-21 for CRC. MATERIALS AND METHODS: Using a random-effect model, the pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to evaluate the diagnostic performance of miR-21 for CRC. A summary receiver operating characteristic (SROC) curve and an area under the curve (AUC) were also generated to assess the diagnosis accuracy of miR-21 for CRC. Q test and I2 statistics were used to assess between- study heterogeneity. Publication bias was evaluated by the Deeks' funnel plot asymmetry test. RESULTS: A total of 986 CRC patients and 702 matched healthy controls from 8 studies were involved in the meta-analysis. The pooled results for SEN, SPE, PLR, NLR, DOR, and AUC were 57% (95%CI: 39%-74%), 87% (95%CI: 78%- 93%), 4.4 (95%CI: 2.4-8.0), 0.49 (95%CI: 0.32-0.74), 9 (95%CI: 4-22), and 0.83 (95%CI: 0.79-0.86), respectively. Subgroup analyses further suggested that blood-based studies showed a better diagnostic accuracy compared with feces-based studies, indicating that blood may be a better matrix for miR-21 assay and CRC detection. CONCLUSIONS: Our findings suggest that miR-21 has a potential diagnostic value for CRC with a moderate level of overall diagnostic accuracy. Hence, it could be used as auxiliary means for the initial screening of CRC and avoid unnecessary colonoscopy, which is an invasive and expensive procedure.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25239640,"Year":2014,"Title":"Clinical potential role of circulating microRNAs in early diagnosis of colorectal cancer patients.","Abstract":"Current procedures for diagnosis and biomarker examination of colorectal cancer (CRC) are invasive and unpleasant. There is a great need to identify sensitive and specific biomarkers for early diagnosis of CRC. Circulating microRNAs (miRNAs) are promising molecular markers for CRC prediction. We performed a comprehensive meta-analysis to integrate an evaluation index for diagnostic accuracy of circulating miRNAs in diagnosing CRC patients. Furthermore, we conducted an independent validation set of 49 CRC patients and 49 healthy controls. In our meta-analysis, we found that miR-21 yielded a pooled area under ROC curve (AUC) of 0.867 (sensitivity: 76%, specificity: 82%) in discriminating CRC from controls, and miR-92a yielded a summary AUC of 0.803 (sensitivity: 77%, specificity: 68%); miR-21 had a higher diagnostic efficiency than miR-92a. In the further validation, plasma miR-21 levels in CRC patients were significantly higher than levels observed in healthy subjects. A ROC curve analysis showed a consistent result. However, this phenotype was not present in miR-92a. Moreover, the expression trend of miR-21 in plasma samples was in line with that of tissue samples, along with the cellular level. Current evidences suggest that plasma miR-21 could be a reliable and non-invasive biomarker for CRC diagnosis. Studies with larger cohorts that include the diagnostic value of plasma miR-21 for CRC are warranted.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25178983,"Year":2014,"Title":"Diagnostic and prognostic value of microRNA-21 in colorectal cancer: an original study and individual participant data meta-analysis.","Abstract":"BACKGROUND: We aimed to systematically summarize the diagnostic and prognostic value of circulating/tissue miR21 in patients with colorectal cancer. METHODS: An original study was conducted to explore the potential value of circulating miR21 in colorectal cancer diagnosis and tissue miR21 in colorectal cancer prognosis. PUBMED and EMBASE were searched (to August, 2013) to identify eligible studies. To explore the diagnostic performance of circulating miR21, meta-analysis methods were used to pool sensitivity, specificity, positive and negative likelihood ratio, diagnostic OR and to construct a summary ROC curve. For prognostic meta-analysis, study-specific HRs of tissue miR21 for survival were summarized. Subgroup and sensitivity analyses were applied to explore heterogeneity. RESULTS: Finally, 14 studies (including our study) were included in the meta-analyses. The pooled sensitivity, specificity, and AUC of circulating miR21 were 0.76 [95% confidence interval (CI), 0.59-0.88], 0.81 (95% CI, 0.76-0.85), and 0.81 (95% CI, 0.78-0.85) in diagnosing colorectal cancer. Patients with higher expression of tissue miR21 had significant inferior overall survival (OS; pooled HR, 1.56; 95% CI, 1.16-2.11) and disease-free survival (DFS; pooled HR, 1.35; 95% CI, 1.08-1.69). The individual participant data (IPD) meta-analysis demonstrated that tissue miR21 level was independently associated with worse colorectal cancer OS (HR, 1.69; 95% CI, 1.07-2.67; P = 0.023), whereas this association seems to be confined to males (P = 0.007) but not for females (P = 0.845). CONCLUSIONS: Circulating miR21 level has potential value for colorectal cancer early detection, whereas high tissue miR21 level is associated with adverse colorectal cancer prognosis. IMPACT: miR21 is a promising biomarker for early detection and prognosis of colorectal cancer. Cancer Epidemiol Biomarkers Prev; 23(12); 2783-92. (c)2014 AACR.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25178939,"Year":2014,"Title":"Elevated level of microRNA-21 in the serum of patients with colorectal cancer.","Abstract":"In patients with colorectal cancer, circulating micro RNA-21 (miR-21) is overexpressed and may act as a potential diagnostic and prognostic biomarker. In the present study, serum miR-21 level was determined in patients with colorectal cancer and control subjects in an attempt to explore its potential clinical diagnostic and prognostic value. Serum levels of miR-21 were measured in 40 patients with colorectal adenocarcinoma and 40 control subjects using a quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) assay. Serum miR-21 levels were compared in the colorectal cancer patients and control subjects. Furthermore, the association between serum miR-21 level and the clinical stages of tumors was also examined in the patients. Serum miR-21 level was significantly elevated in colorectal adenocarcinoma patients relative to control subjects (P=0.0001), and it was revealed as a potential diagnostic biomarker for differentiating the patients from control subjects. Increased levels of serum miR-21 were associated with clinical stages of tumors in the patients (P=0.01). These results indicated that serum miR-21 levels could serve as a reliable diagnostic and prognostic biomarker for colorectal adenocarcinoma.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25092886,"Year":2014,"Title":"Dietary manipulation of oncogenic microRNA expression in human rectal mucosa: a randomized trial.","Abstract":"High red meat (HRM) intake is associated with increased colorectal cancer risk, while resistant starch is probably protective. Resistant starch fermentation produces butyrate, which can alter microRNA (miRNA) levels in colorectal cancer cells in vitro; effects of red meat and resistant starch on miRNA expression in vivo were unknown. This study examined whether a HRM diet altered miRNA expression in rectal mucosa tissue of healthy volunteers, and if supplementation with butyrylated resistant starch (HRM+HAMSB) modified this response. In a randomized cross-over design, 23 volunteers undertook four 4-week dietary interventions; an HRM diet (300 g/day lean red meat) and an HRM+HAMSB diet (HRM with 40 g/day butyrylated high amylose maize starch), preceded by an entry diet and separated by a washout. Fecal butyrate increased with the HRM+HAMSB diet. Levels of oncogenic mature miRNAs, including miR17-92 cluster miRNAs and miR21, increased in the rectal mucosa with the HRM diet, whereas the HRM+HAMSB diet restored miR17-92 miRNAs, but not miR21, to baseline levels. Elevated miR17-92 and miR21 in the HRM diet corresponded with increased cell proliferation, and a decrease in miR17-92 target gene transcript levels, including CDKN1A. The oncogenic miR17-92 cluster is differentially regulated by dietary factors that increase or decrease risk for colorectal cancer, and this may explain, at least in part, the respective risk profiles of HRM and resistant starch. These findings support increased resistant starch consumption as a means of reducing risk associated with an HRM diet.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25081869,"Year":2014,"Title":"Low expression levels of microRNA-124-5p correlated with poor prognosis in colorectal cancer via targeting of SMC4.","Abstract":"A component of polycomb repressor complex 2, enhancer of zeste homolog 2 (EZH2), plays an important role in tumor malignancy and metastasis, while milk fat globule-epidermal growth factor-factor 8 (MFGE8) plays a key role in tumor progression and prognosis. MicroRNAs (miRs) are also critically involved in various physiological and pathological processes. We here evaluated the relationship between overall survival (OS) in colorectal cancer patients and the expression of onco-miRs and miRs, which may target EZH2 and MFGE8. Plasma and formalin-fixed paraffin-embedded (FFPE) samples were obtained from 71 colorectal cancer patients. The expression levels of miRs complementary to EZH2 and MFGE8 mRNA and cancer malignancies were evaluated. The miRs analyzed were as follows: miR-16, miR-21, miR-26a, miR-34a, miR-98, miR-101-3p, miR-101-5p, miR-124-5p (also known as miR-124*), miR-126-3p, miR-126-5p, miR-210, miR-217, and miR-630. The plasma expression levels of MFGE8 in completely resected patients were significantly lower than those in unresectable patients. Lower miR-26a expression levels were correlated with a higher probability of OS. Higher miR-124-5p expression levels in plasma and FFPE samples were correlated with a higher probability of OS. The transfection of mimic miR-124-5p into WiDr and COLO201 cells inhibited the expression of structural maintenance of chromosomes 4 (SMC4) mRNA. Our results indicate that miR-124-5p may target the tumorigenesis gene, SMC4, which suggests that expression levels of miR-124-5p in plasma and FFPE samples; therefore, the expression of MFGE8, miR-26a, and miR-124-5p in plasma may be used as biomarkers to determine the prognosis of colorectal cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25051407,"Year":2014,"Title":"Redefining high-risk patients with stage II colon cancer by risk index and microRNA-21: results from a population-based cohort.","Abstract":"BACKGROUND: The aim of the present study was to analyse the prognostic value of microRNA-21 (miRNA-21) in patients with stage II colon cancer aiming at a risk index for this group of patients. METHODS: A population-based cohort of 554 patients was included. MicroRNA-21 was analysed by qPCR based on tumour tissue. An index was created using the coefficients obtained from a collective multiple Cox regression. The entire procedure was cross-validated (10-fold). The performance of the index was quantified by time-dependent receiver operating characteristics curves. RESULTS: High miRNA-21 expression was associated with an unfavourable recurrence-free cancer-specific survival (RF-CSS), hazard ratio 1.35 (95% confidence interval, 1.03-1.76) (P=0.028). The generated RF-CSS index divided the traditional high-risk patients into subgroups with 5-year RF-CSS rates of 87% and 73%, respectively (P<0.001). The overall survival (OS) index identified three different subgroups (P<0.001). Cross-validated 5-year OS rates were 88%, 68%, and 50%, respectively. CONCLUSIONS: This population-based study supports miRNA-21 as an additional prognostic biomarker in patients with stage II colon cancer. Furthermore, the introduction of a risk index may guide the use of postoperative adjuvant treatment in a more appropriate way compared with current practice.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":25040971,"Year":2014,"Title":"MicroRNAs as promising biomarkers for tumor-staging: evaluation of MiR21 MiR155 MiR29a and MiR92a in predicting tumor stage of rectal cancer.","Abstract":"OBJECTIVE: In this study, tumor-stage predictive abilities of miR21, miR155, miR29a and miR92a were evaluated in rectal cancer (RC). METHODS: Expression of miR21, miR155, miR29a and miR92a was detected and quantitated in tumor tissue and in adjacent normal tissue from 40 patients by TaqMan MicroRNA assay. RESULTS: Significant overexpression of miR21, miR155, miR29a and miR92a was observed in RC tissues. While high expression of miR21, miR155 and miR29a in N1-2 and C-D stages presented a potential correlation with N and Duke stages, partial correlation analysis suggested that only miR155 rather than miR21 and miR29a played a greater influencing role. Receiver operating characteristics (ROC) curve analysis showed that miR155 could discriminate N0 from N1-2 with 85.0% sensitivity and 85.0% specificity, N2 from N0-1 with 90.0% sensitivity and 96.7% specificity, and C-D stage from A-B stage with 81.0% sensitivity and 84.2% specificity. CONCLUSIONS: Increase in expression of miR155 might represent a novel predictor for RC N and Dukes staging.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24955156,"Year":2014,"Title":"Prognostic value of circulating microRNA-21 in digestive system cancers: a meta-analysis.","Abstract":"UNLABELLED: Circulating microRNAs show aberrant expression in patients with cancer. The aim of this study was to investigate the prognostic value of circulating microRNA-21 (miR-21) in digestive system cancers. METHODS: All the eligible studies were searched by Medline and EMBASE. The hazard ratios (HRs) for overall survival (OS), which compared the expression levels of circulating miR-21 in patients with digestive cancer was extracted and estimated. Pooled HRs and 95% confidence intervals (CI) were calculated. Then a meta-analysis was performed to clarify the prognostic value of the miR-21. RESULTS: A total of seven studies involving 907 subjects were included. The results suggested that higher circulating miR-21 could predict worse OS outcome with the pooled HR of 2.19 (95% CI 1.01-4.75, P = 0.05) in digestive system cancers. Subgroup analysis by ethnicity indicated circulating miR-21 was associated with OS in patients with digestive cancer among Asians with the pooled HR of 2.90 (95% CI 1.30-6.45, P = 0.009). However, subgroup analysis by digestive system site revealed that there is no associated with OS in patients with colorectal cancer with the pooled HR of 1.34 (95% CI 0.45-4.00, P = 0.60). CONCLUSION: The present findings suggest that circulating miR-21 is associated with poor survival in patients with digestive cancer and could be a prognostic biomarker for those patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24938624,"Year":2014,"Title":"MicroRNA target prediction: theory and practice.","Abstract":"The present study is one of the few that includes tissue samples in the evaluation of target prediction algorithms designed to detect microRNA (miRNA) sequences that might interact with particular messenger RNA (mRNA) sequences. Twelve different target prediction tools were used to find miRNA sequences that might interact with CCL20 gene expression. Different algorithms predicted controversial miRNA sequences for CCL20 regulation due to a different weighting of parameters. Hsa-miR-21 and hsa-miR-145 suggested by four or more programs were chosen for further investigation. Possible real interaction of these miRNA sequences with CCL20 gene expression was monitored using luciferase assays and expression analyses of tissue samples of colorectal adenocarcinoma by either qRT-PCR or ELISA. Folding status of seed-binding sites in complete mRNA and 3'UTR of CCL20 was predicted. Prediction of miRNA expression was attempted based on CCL20 expression data. Eight of the target prediction tools forecasted a role for hsa-miR-21 and four mentioned hsa-miR-145 in CCL20 gene regulation. Laboratory experimentation showed that CCL20 may serve as a target of hsa-miR-21 but not hsa-miR-145. Expression of the molecules resulted in no clear assertion. Folding of seed-binding sites was predicted to be relatively constant for the complete mRNA and 3'UTR. Predicting miRNA expression based on target gene expression was impossible. This might be attributable to the fact that effects of miRNA activity may oscillate between gene product repression and activation. Additional systematic studies are needed to address this issue.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24921248,"Year":2014,"Title":"MicroRNA profiles discriminate among colon cancer metastasis.","Abstract":"MicroRNAs are being exploited for diagnosis, prognosis and monitoring of cancer and other diseases. Their high tissue specificity and critical role in oncogenesis provide new biomarkers for the diagnosis and classification of cancer as well as predicting patients' outcomes. MicroRNAs signatures have been identified for many human tumors, including colorectal cancer (CRC). In most cases, metastatic disease is difficult to predict and to prevent with adequate therapies. The aim of our study was to identify a microRNA signature for metastatic CRC that could predict and differentiate metastatic target organ localization. Normal and cancer tissues of three different groups of CRC patients were analyzed. RNA microarray and TaqMan Array analysis were performed on 66 Italian patients with or without lymph nodes and/or liver recurrences. Data obtained with the two assays were analyzed separately and then intersected to identify a primary CRC metastatic signature. Five differentially expressed microRNAs (hsa-miR-21, -103, -93, -31 and -566) were validated by qRT-PCR on a second group of 16 American metastatic patients. In situ hybridization was performed on the 16 American patients as well as on three distinct commercial tissues microarray (TMA) containing normal adjacent colon, the primary adenocarcinoma, normal and metastatic lymph nodes and liver. Hsa-miRNA-21, -93, and -103 upregulation together with hsa-miR-566 downregulation defined the CRC metastatic signature, while in situ hybridization data identified a lymphonodal invasion profile. We provided the first microRNAs signature that could discriminate between colorectal recurrences to lymph nodes and liver and between colorectal liver metastasis and primary hepatic tumor.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24832083,"Year":2014,"Title":"MicroRNA-21 promotes tumour malignancy via increased nuclear translocation of beta-catenin and predicts poor outcome in APC-mutated but not in APC-wild-type colorectal cancer.","Abstract":"MiR-21 has been associated with poor prognosis in colon adenocarcinomas. However, in our preliminary data, the prognostic value of miR-21 levels was observed only in adenomatous polyposis coli (APC)-mutated tumours, not in APC-wild-type tumours. We explored whether beta-catenin nuclear translocation was synergistically promoted by miR-21 in APC-mutated cells but not in APC-wild-type cells. We enrolled 165 colorectal tumour to determine APC mutation, miR-21 levels and nuclear beta-catenin expression by direct sequencing, real-time PCR and immunohistochemistry. Overall survival and relapse-free survival were analysed by Kaplan-Meier and Cox regression models. The mechanistic action of beta-catenin nuclear translocation modulated by miR-21 and its effect on cell invasion were evaluated in a cell model. Positive nuclear beta-catenin expression was more commonly occurred in APC-mutated tumours than in APC-wild-type tumours. High miR-21 levels were relatively more common in tumours with positive nuclear beta-catenin expression than in those with negative nuclear beta-catenin expression. APC-mutated tumours with high miR-21 levels had shorter overall survival and relapse-free survival periods compared with others. However, the prognostic value of miR-21 levels was not observed in APC-wild-type tumours. Phosphorylation of beta-catenin at Ser552 via the miR-21-mediated PTEN/AKT axis plays a critical role in beta-catenin nuclear translocation in APC-mutated cells but not in APC-wild-type cells. Moreover, nuclear beta-catenin expression increased by miR-21 is responsible for the capability of invasiveness. In summary, nuclear translocation of beta-catenin increased by miR-21 promotes tumour malignancy and a poor outcome in APC-mutated patients but not in APC-wild-type colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24800242,"Year":2014,"Title":"MicroRNAs 146a and 147b biomarkers for colorectal tumor's localization.","Abstract":"The recently identified class of microRNAs (miRs) provided a new insight into cancer research, since abnormalities of members of microRNAs family have been found in various types of cancer. However, the relationship between five miRNAs (miR146a, miR155, miR21, miR135a, and miR147b) and colorectal cancer remains unclear. In the present study, we examined expression of these miRNAs in 25 pair-matched colon cancer tissues and normal colon mucosa. The expression levels of miR146a, miR155, miR21, miR135a, and miR147b were quantified by real-time PCR. We found that miR21, miR146a, and miR135a were all expressed at higher levels in colon tumors. On the other hand, miR146a and miR147b expressions are significantly higher in left colon compared to right colon. These two miRs, especially miR146a, seemed to be markers for the left colon tumors. Moreover, significant proportional and inverse correlations were found between miR expressions in tumor and healthy tissue, and the correlations profiles were different depending on cancer localization. Taken together, these results lead us to suggest the presence of different mechanisms regulating miRs expression and consequently their target genes in left and right colon. So the pathway of colorectal carcinogenesis would be different according to the site of the tumor.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24780321,"Year":2014,"Title":"Correlation of over-expressions of miR-21 and Notch-1 in human colorectal cancer with clinical stages.","Abstract":"AIM: The aim of the study was to identify expressions of Notch-1, microRNA-21 (miR-21), and phosphatase and tensin homolog (PTEN) in colorectal cancer (CRC), and to explore their relationship with clinical stages and metastatic status of CRC. MAIN METHODS: 102 CRC patients were enrolled and clinical data were analyzed. Expressions of Notch-1 and miR-21 in CRC and adjacent non-tumor tissues of these patients were measured by real time-PCR. Protein expressions of Notch-1 and PTEN of 12 paired tissues were determined by Western blot and immunohistochemistry. The correlations between gene expressions in different clinical stages as well as metastatic status were evaluated by linear regression. KEY FINDINGS: Notch-1 was over-expressed in 86.27% (88/102) CRC tissues, particularly in advanced stages, while miR-21 expression was increased to 74.51% (76/102) in CRC tissues compared with matched adjacent non-tumor tissues. The expressions of Notch-1 and miR-21 were positively correlated with CRC development, especially in advanced-stages (r(2)=0.3839, p<0.01). Expressions of PTEN were significantly down-regulated in CRC tissues and negatively correlated with expressions of Notch-1 (r(2)=0.5207, p<0.01) and miR-21 (r(2)=0.6996, p<0.01). SIGNIFICANCE: These data indicate that the crosstalk between Notch-1 and miR-21 is involved in CRC development through degradation of PTEN.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24709885,"Year":2014,"Title":"Identification of a circulating microRNA signature for colorectal cancer detection.","Abstract":"Prognosis of patients with colorectal cancer (CRC) is generally poor because of the lack of simple, convenient, and noninvasive tools for CRC detection at the early stage. The discovery of microRNAs (miRNAs) and their different expression profiles among different kinds of diseases has opened a new avenue for tumor diagnosis. We built a serum microRNA expression profile signature and tested its specificity and sensitivity as a biomarker in the diagnosis of CRC. We also studied its possible role in monitoring the progression of CRC. We conducted a two phase case-control test to identify serum miRNAs as biomarkers for CRC diagnosis. Using quantitative reverse transcription polymerase chain reactions, we tested ten candidate miRNAs in a training set (30 CRCs vs 30 controls). Risk score analysis was used to evaluate the diagnostic value of the serum miRNA profiling system. Other independent samples, including 83 CRCs and 59 controls, were used to validate the diagnostic model. In the training set, six serum miRNAs (miR-21, let-7g, miR-31, miR-92a, miR-181b, and miR-203) had significantly different expression levels between the CRCs and healthy controls. Risk score analysis demonstrated that the six-miRNA-based biomarker signature had high sensitivity and specificity for distinguishing the CRC samples from cancer-free controls. The areas under the receiver operating characteristic (ROC) curve of the six-miRNA signature profiles were 0.900 and 0.923 for the two sets of serum samples, respectively. However, for the same serum samples, the areas under the ROC curve used by the tumor markers carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were only 0.649 and 0.598, respectively. The expression levels of the six serum miRNAs were also correlated with CRC progression. Thus, the identified six-miRNA signature can be used as a noninvasive biomarker for the diagnosis of CRC, with relatively high sensitivity and specificity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24705249,"Year":2014,"Title":"Circulating exosomal microRNAs as biomarkers of colon cancer.","Abstract":"PURPOSE: Exosomal microRNAs (miRNAs) have been attracting major interest as potential diagnostic biomarkers of cancer. The aim of this study was to characterize the miRNA profiles of serum exosomes and to identify those that are altered in colorectal cancer (CRC). To evaluate their use as diagnostic biomarkers, the relationship between specific exosomal miRNA levels and pathological changes of patients, including disease stage and tumor resection, was examined. EXPERIMENTAL DESIGN: Microarray analyses of miRNAs in exosome-enriched fractions of serum samples from 88 primary CRC patients and 11 healthy controls were performed. The expression levels of miRNAs in the culture medium of five colon cancer cell lines were also compared with those in the culture medium of a normal colon-derived cell line. The expression profiles of miRNAs that were differentially expressed between CRC and control sample sets were verified using 29 paired samples from post-tumor resection patients. The sensitivities of selected miRNAs as biomarkers of CRC were evaluated and compared with those of known tumor markers (CA19-9 and CEA) using a receiver operating characteristic analysis. The expression levels of selected miRNAs were also validated by quantitative real-time RT-PCR analyses of an independent set of 13 CRC patients. RESULTS: The serum exosomal levels of seven miRNAs (let-7a, miR-1229, miR-1246, miR-150, miR-21, miR-223, and miR-23a) were significantly higher in primary CRC patients, even those with early stage disease, than in healthy controls, and were significantly down-regulated after surgical resection of tumors. These miRNAs were also secreted at significantly higher levels by colon cancer cell lines than by a normal colon-derived cell line. The high sensitivities of the seven selected exosomal miRNAs were confirmed by a receiver operating characteristic analysis. CONCLUSION: Exosomal miRNA signatures appear to mirror pathological changes of CRC patients and several miRNAs are promising biomarkers for non-invasive diagnosis of the disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24653631,"Year":2014,"Title":"Differential expression of serum miR-126, miR-141 and miR-21 as novel biomarkers for early detection of liver metastasis in colorectal cancer.","Abstract":"OBJECTIVE: MicroRNAs (miRNAs) have potential as diagnostic biomarkers in cancer. Evaluation of the association between miRNA expression patterns and early detection of liver metastasis in colorectal cancer (CRC) has not been reported. METHODS: We investigated the expression of metastasis-associated miRs-31, 335, 206, 141, 126, 200b, 200c, 21, Let7a, Let7b and Let7c in localized, liver-metastatic and other organ-metastatic CRC (OM-CRC). Expressions of target miRNAs in serum were evaluated in 116 consecutive localized CRC (L-CRC), 72 synchronous liver-metastatic CRC (SLM-CRC) and 36 other OM-CRC by quantitative real-time PCR. RESULTS: Seven of 11 tested miRNAs could be detected from serum. Four miRNAs, miR-126, Let-7a, miR-141 and miR-21 were identified as metastasis-associated miRNAs. Compared with L-CRC, significant up-regulated expression was observed for miR-141 and miR-21 in SLM-CRC and OM-CRC, down-regulated expression was observed for miR-126 in SLM-CRC and OM-CRC, and up-regulated expression of Let-7a in OM-CRC. The receiver operating characteristic (ROC) curve showed serum miR-126 had a cut-off [log10 relative quantity (log10 (RQ))=-0.2005] with 77.78% sensitivity and 68.97% specificity with an area under curve (AUC) of 0.7564, miR-141 had a cut-off (log10 (RQ)=-0.2285) with 86.11% sensitivity and 76.11% specificity with an AUC of 0.8279, and miR-21 had a cut-off (log10 (RQ)=-0.1310) with 73.61% sensitivity and 66.38% specificity with an AUC of 0.7479. CONCLUSIONS: We identified liver metastasis-associated miRNAs, suggesting serum miR-126, miR-141 and miR-21 may be novel biomarkers for clinical diagnosis of early stage liver-metastatic CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24468585,"Year":2014,"Title":"MiR-20b, -21, and -130b inhibit PTEN expression resulting in B7-H1 over-expression in advanced colorectal cancer.","Abstract":"Co-inhibitor B7-H1 expresses in various cancers and contributes to cancer immune evasion by inhibiting T cell activation and proliferation, yet the regulatory mechanisms for B7-H1 over-expression in cancers remain largely unknown. Here, the expression of B7-H1 and PTEN proteins were firstly detected by using immunohistochemistry method. B7-H1 immunoreactivities were found in 54.5% (55/101) of the colorectal cancer tissues with no expression in the normal tissues, and the PTEN protein immunoreactivities were observed in 51.5% (52/101) of the colorectal cancer tissues and 72.3% (73/101) of the normal tissues. Statistical analysis results indicated that the B7-H1 expression was negatively correlated to the PTEN expression in colorectal cancer (p=0.001). Then the expressions of microRNAs (miRNAs) in six pairs of colorectal cancer and normal tissues were determined by miRNA array, and 30 up-regulated miRNAs were found in the colorectal cancer tissues. Finally, the impact of these up-regulated miRNAs on PTEN expression was tested by using dual-luciferase reporter assay system, from which the results indicated that miR-20b, -21, and -130b were involved in suppression of PTEN expression. These findings suggest that miR-20b, -21, and -130b, up-regulated in colorectal cancer, through inhibiting the expression of PTEN, result in B7-H1 over-expression in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24423916,"Year":2014,"Title":"Circulating miR-378 in plasma: a reliable, haemolysis-independent biomarker for colorectal cancer.","Abstract":"BACKGROUND: Plasma circulating tumour-specific microRNAs (miRNAs) are promising biomarkers of tumour presence and recurrence, especially for diseases whose best chance of successful treatment requires early diagnosis and timely surgery of an already malignant but not yet invasive tumour, such as colorectal cancer (CRC). METHODS: Expression levels of miRNAs previously found to be differently expressed in tumour vs normal colon tissues were investigated by quantitative real-time PCR in plasma from CRC patients and from healthy donors and confirmed in independent case control series. The validated miRNAs were also measured after surgery. Analyses were repeated on the subsets of haemolysis-free samples. RESULTS: We identified four miRNAs differently expressed between the compared groups, two (miR-21 and miR-378) of which were validated. miR-378 expression decreased in non-relapsed patients 4-6 months after surgery and miR-378 ability to discriminate CRC patients from healthy individuals was not influenced by haemolysis levels of plasma samples. CONCLUSION: The miRNA analysis on plasma samples represents a useful non-invasive tool to assess CRC presence as well as tumour-free status at follow-up. Plasma levels of miR-378 could be used to discriminate CRC patients from healthy individuals, irrespective of the level of haemoglobin of plasma samples.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24420840,"Year":2015,"Title":"Prenatal and neonatal exposure to perfluorooctane sulfonic acid results in aberrant changes in miRNA expression profile and levels in developing rat livers.","Abstract":"Perfluorooctane sulfonate (PFOS) is an animal carcinogen. However, the underlying mechanism in cancer initiation is still largely unknown. Recently identified microRNAs (miRNAs) may play an important role in toxicant exposure and in the process of toxicant-induced tumorigenesis. We used PFOS to investigate PFOS-induced changes in miRNA expression in developing rat liver and the potential mechanism of PFOS-induced toxic action. Dams received 3.2 mg/kg PFOS in their feed from gestational day 1 (GD1) to postnatal day 7 (PND 7). Pups then had free access to treated feed until PND 7. We isolated RNAs from liver tissues on PND 1 and 7 and analyzed the expression profiles of 387 known rat miRNAs using microarray technology. PFOS exposure induced significant changes in miRNA expression profiles. Forty-six miRNAs had significant expression alterations on PND 1, nine miRNAs on PND 7. Specifically, expression of four miRNAs was up-regulated on PND 7 but down-regulated on PND1 (p < 0.05). Many aberrantly expressed miRNAs were related to various cancers. We found oncogenic and tumor-suppressing miRNAs, which included miR-19b, miR-21*, miR-17-3p, miR-125a-3p, miR-16, miR-26a, miR-1, miR-200c, and miR-451. In addition, four miRNAs were simultaneous significantly expressed on both PND 1 and 7. Functional Annotation analysis of the predicted transcript targets revealed that PFOS exposure potentially alters pathways associated with different cancers (cancer, melanoma, pancreatic cancer, colorectal cancer, and glioma), biological processes which include positive regulation of apoptosis and cell proliferation. Results showed PFOS exposure altered the expression of a suite of miRNAs. (c) 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 712-723, 2015.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24275137,"Year":2014,"Title":"Targeting miR-21 enhances the sensitivity of human colon cancer HT-29 cells to chemoradiotherapy in vitro.","Abstract":"5-Fluorouracil (5-FU) is a classic chemotherapeutic drug that has been widely used for colorectal cancer treatment, but colorectal cancer cells are often resistant to primary or acquired 5-FU therapy. Several studies have shown that miR-21 is significantly elevated in colorectal cancer. This suggests that this miRNA might play a role in this resistance. In this study, we investigated this possibility and the possible mechanism underlying this role. We showed that forced expression of miR-21 significantly inhibited apoptosis, enhanced cell proliferation, invasion, and colony formation ability, promoted G1/S cell cycle transition and increased the resistance of tumor cells to 5-FU and X radiation in HT-29 colon cancer cells. Furthermore, knockdown of miR-21 reversed these effects on HT-29 cells and increased the sensitivity of HT-29/5-FU to 5-FU chemotherapy. Finally, we showed that miR-21 targeted the human mutS homolog2 (hMSH2), and indirectly regulated the expression of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). These results demonstrate that miR-21 may play an important role in the 5-FU resistance of colon cancer cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24265822,"Year":2013,"Title":"Prognostic role of microRNA-21 in colorectal cancer: a meta-analysis.","Abstract":"BACKGROUND: To date, many studies have shown that microRNAs (miRNA) exhibit altered expression in various cancers and may play an important role as prognostic biomarker of cancers. The present meta-analysis summarizes the recent advances in the use of microRNA-21 (miR-21) in the assessment of colorectal cancer and analyzes the prognostic role of miR-21 for survival outcome. METHODOLOGY/PRINCIPAL FINDINGS: The present meta-analysis was performed by searching PubMed through multiple search strategies. Data were extracted from studies comparing overall survival (OS) in patients with colorectal cancer who showed higher expression of miR-21 than similar patients. Pooled hazard ratios (HRs) of miR-21 for survival and 95% confidence intervals (CI) were calculated. Seven studies with a total of 1174 patients were included this meta-analysis. For overall survival (OS), the pooled hazard ratio (HR) of higher miR-21 expression in colorectal cancer was 1.76 (95% CI: 1.34-2.32, P=0.000). After elimination of heterogeneity, the pooled HR was 2.32 (95% CI: 1.82-2.97, P=0.000), which was found to significantly predict poorer survival. The subgroup analysis suggested that elevated miR-21 level and patients' survival correlated with III/IV stage (HR=5.35, 95% CI: 3.73-7.66). CONCLUSIONS/SIGNIFICANCE: The present findings suggest that high expression of miR-21 might predict poor prognosis in patients with colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24239208,"Year":2013,"Title":"Prognostic and predictive value of a microRNA signature in stage II colon cancer: a microRNA expression analysis.","Abstract":"BACKGROUND: Current staging methods do not accurately predict the risk of disease recurrence and benefit of adjuvant chemotherapy for patients who have had surgery for stage II colon cancer. We postulated that expression patterns of multiple microRNAs (miRNAs) could, if combined into a single model, improve postoperative risk stratification and prediction of chemotherapy benefit for these patients. METHOD: Using miRNA microarrays, we analysed 40 paired stage II colon cancer tumours and adjacent normal mucosa tissues, and identified 35 miRNAs that were differentially expressed between tumours and normal tissue. Using paraffin-embedded specimens from a further 138 patients with stage II colon cancer, we confirmed differential expression of these miRNAs using qRT-PCR. We then built a six-miRNA-based classifier using the LASSO Cox regression model, based on the association between the expression of every miRNA and the duration of individual patients' disease-free survival. We validated the prognostic and predictive accuracy of this classifier in both the internal testing group of 138 patients, and an external independent group of 460 patients. FINDINGS: Using the LASSO model, we built a classifier based on the six miRNAs: miR-21-5p, miR-20a-5p, miR-103a-3p, miR-106b-5p, miR-143-5p, and miR-215. Using this tool, we were able to classify patients between those at high risk of disease progression (high-risk group), and those at low risk of disease progression (low-risk group). Disease-free survival was significantly different between these groups in every set of patients. In the initial training group of patients, 5-year disease-free survival was 89% (95% CI 77.3-94.4) for the low-risk group, and 60% (46.3-71.0) for the high-risk group (hazard ratio [HR] 4.24, 95% CI 2.13-8.47; p<0.0001). In the internal testing set of patients, 5-year disease-free survival was 85% (95% CI 74.3-91.8) for the low-risk group, and 57% (42.8-68.5) for the high-risk group (HR 3.63, 1.86-7.01; p<0.0001), and in the independent validation set of patients, was 85% (79.6-89.0) for the low-risk group and 54% (46.4-61.1) for the high-risk group (HR 3.70, 2.56-5.35; p<0.0001). The six-miRNA-based classifier was an independent prognostic factor for, and had better prognostic value than, clinicopathological risk factors and mismatch repair status. In an ad-hoc analysis, the patients in the high-risk group were found to have a favourable response to adjuvant chemotherapy (HR 1.69, 1.17-2.45; p=0.0054). We developed two nomograms for clinical use that integrated the six-miRNA-based classifier and four clinicopathological risk factors to predict which patients might benefit from adjuvant chemotherapy after surgery for stage II colon cancer. CONCLUSION: Our six-miRNA-based classifier is a reliable prognostic and predictive tool for disease recurrence in patients with stage II colon cancer, and might be able to predict which patients benefit from adjuvant chemotherapy. It might facilitate patient counselling and individualise management of patients with this disease. FUNDING: Natural Science Foundation of China.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24149370,"Year":2014,"Title":"Epigenetic regulation of miR-21 in colorectal cancer: ITGB4 as a novel miR-21 target and a three-gene network (miR-21-ITGBeta4-PDCD4) as predictor of metastatic tumor potential.","Abstract":"Previous studies have uncovered several transcription factors that determine biological alterations in tumor cells to execute the invasion-metastasis cascade, including the epithelial-mesenchymal transition (EMT). We sought to investigate the role of miR-21 in colorectal cancer regulation. For this purpose, miR-21 expression was quantified in a panel of colorectal cancer cell lines and clinical specimens. High expression was found in cell lines with EMT properties and in the vast majority of human tumor specimens. We demonstrate in a cell-specific manner the occupancy of MIR-21 gene promoter by AP-1 and ETS1 transcription factors and, for the first time, the pattern of histone posttranslational modifications necessary for miR-21 overexpression. We also show that Integrin-beta4 (ITGbeta4), exclusively expressed in polarized epithelial cells, is a novel miR-21 target gene and plays a role in the regulation of EMT, since it is remarkably de-repressed after transient miR-21 silencing and downregulated after miR-21 overexpression. miR-21-dependent change of ITGbeta4 expression significantly affects cell migration properties of colon cancer cells. Finally, in a subgroup of tumor specimens, ROC curve analysis performed on quantitative PCR data sets for miR-21, ITGbeta4, and PDCD4 shows that the combination of high miR-21 with low ITGbeta4 and PDCD4 expression is able to predict presence of metastasis. In conclusion, miR-21 is a key player in oncogenic EMT, its overexpression is controlled by the cooperation of genetic and epigenetic alterations, and its levels, along with ITGbeta4 and PDCD4 expression, could be exploited as a prognostic tool for CRC metastasis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":24122631,"Year":2014,"Title":"High miR-21 expression from FFPE tissues is associated with poor survival and response to adjuvant chemotherapy in colon cancer.","Abstract":"Colon cancer (CC) is a leading cause of cancer mortality. Novel biomarkers are needed to identify CC patients at high risk of recurrence and those who may benefit from therapeutic intervention. The aim of this study is to investigate if miR-21 expression from RNA isolated from formalin-fixed paraffin-embedded (FFPE) tissue sections is associated with prognosis and therapeutic outcome for patients with CC. The expression of miR-21 was measured by quantitative reverse transcriptase-polymerase chain reaction in a Japanese cohort (stage I-IV, n = 156) and a German cohort (stage II, n = 145). High miR-21 expression in tumors was associated with poor survival in both the stage II/III Japanese (p = 0.0008) and stage II German (p = 0.047) cohorts. These associations were independent of other clinical covariates in multivariable models. Receipt of adjuvant chemotherapy was not beneficial in patients with high miR-21 in either cohort. In the Japanese cohort, high miR-21 expression was significantly associated with poor therapeutic outcome (p = 0.0001) and adjuvant therapy was associated with improved survival in patients with low miR-21 (p = 0.001). These results suggest that miR-21 is a promising biomarker to identify patients with poor prognosis and can be accurately measured in FFPE tissues. The expression of miR-21 may also identify patients who will benefit from adjuvant chemotherapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23970420,"Year":2013,"Title":"Prognostic implications of serum microRNA-21 in colorectal cancer.","Abstract":"BACKGROUND AND OBJECTIVES: MicroRNAs (miRNAs) are small, noncoding RNAs that are involved in carcinogenesis through postranscriptional gene regulatory activity. Few studies have focused on the detection of miR-21 in serum rather than in tissue. The current study aimed to measure serum miR-21 expression levels and to evaluate their association with the outcome of colorectal cancer (CRC). METHODS: Blood samples were collected from 102 CRC patients undergoing surgery with curative intent. The expression levels of miR-21 were measured using a quantitative reverse transcription polymerase chain reaction (qRT-PCR). The results were analysed to assess the relationship between serum miR-21 levels and patient survival. RESULTS: A univariate analysis revealed that lower expression levels of serum miR-21 were associated with higher local recurrence (P = 0.025) and mortality (P = 0.029). A logistic regression analysis demonstrated that the relative overexpression of miR-21 (expression > 1) was associated with a 51% reduction in the risk of recurrence. A Cox regression analysis identified miR-21 expression as an independent predictor of survival (P = 0.048); a relative increase in miR-21 expression (>1) was associated with a 50% reduction in the risk of mortality. CONCLUSION: The expression level of serum miR-21 correlates with the recurrence and mortality of CRC patients. Our results suggest that circulating serum miR-21 is a promising prognostic tumour marker, and they highlight the potential clinical utility of miR-21 expression as a prognostic marker for CRC prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23894315,"Year":2013,"Title":"Difluorinated-curcumin (CDF) restores PTEN expression in colon cancer cells by down-regulating miR-21.","Abstract":"Despite recent advancement in medicine, nearly 50% of patients with colorectal cancer show recurrence of the disease. Although the reasons for the high relapse are not fully understood, the presence of chemo- and radiotherapy-resistant cancer stem/stem-like cells, where many oncomirs like microRNA-21 (miR-21) are upregulated, could be one of the underlying causes. miR-21 regulates the processes of invasion and metastasis by downregulating multiple tumor/metastatic suppressor genes including PTEN (phosphatase and tensin homolog). Tumor suppressor protein PTEN controls self-renewal of stem cells. Indeed, our current data demonstrate a marked downregulation of PTEN in SCID mice xenografts of miR-21 over-expressing colon cancer HCT116 cells. Colonospheres that are highly enriched in cancer stem/stem like cells reveal increased miR-21 expression and decreased PTEN. Difluorinated curcumin (CDF), a novel analog of the dietary ingredient curcumin, which has been shown to inhibit the growth of 5-Flurouracil + Oxaliplatin resistant colon cancer cells, downregulated miR-21 in chemo-resistant colon cancer HCT116 and HT-29 cells and restored PTEN levels with subsequent reduction in Akt phosphorylation. Similar results were also observed in metastatic colon cancer SW620 cells. Since PTEN-Akt confers drug resistance to different malignancies including colorectal cancer, our observation of normalization of miR-21-PTEN-Akt pathway by CDF suggests that the compound could be a potential therapeutic agent for chemotherapy-resistant colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23858763,"Year":2013,"Title":"[Construction of microRNA-21 and PTEN eukaryotic expression and short hairpin RNA expression vectors].","Abstract":"The aim of the present study is to construct the recombinant eukaryotic expression and short hairpin RNA (shRNA) expression vectors of microRNA-21 and phosphatase and tensin homolog deleted on chromosome ten (PTEN). According to the gene sequence of microRNA-21 and PTEN, we designed and synthesized two pairs of single-stranded siRNA oligonucleotides and PCR primers. After annealing, the double-stranded DNA oligonucleotides were cloned into vector Psilencer4. 1-CMV. In addition, the gene sequences encoding pre-miR-21 and PTEN were amplified from colorectal cancer cell HCT-116 by RT-PCR. Then the PCR products were digested with restrictive endonuclease enzyme and cloned into vector pEGFP-N1. The constructed recombinant vectors were identified by restrictive digestion and DNA sequence analysis. The positive clone was confirmed by double enzyme digestion, and the enzyme fragments were consistent with the vector and purpose gene sequence. DNA sequencing confirmed that the purpose oligonucleotide fragments were correctly inserted in to the eukaryotic expression plasmids. It could be concluded that the microRNA-21 and PTEN eukaryotic expression and shRNA expression vectors have been successfully constructed, providing a foundation for further study on the effect of miR-21 on human colorectal cancer.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23827854,"Year":2013,"Title":"Aldose reductase inhibition suppresses colon cancer cell viability by modulating microRNA-21 mediated programmed cell death 4 (PDCD4) expression.","Abstract":"Inhibition of polyol pathway enzyme aldose reductase (AR) has been shown to prevent colon cancer cells growth in culture and in nude mice xenografts. However, the role of AR in the mediation of growth factor-induced colon cancer cells growth is not well understood. In this study, we have investigated how AR inhibition prevents tumour growth via regulation of microRNA (miR)-21-mediated programmed cell death 4 (PDCD4) expression in colon cancer cells in in vitro and in vivo. Treatment of colon cancer cells (HT29, SW480 and Caco-2) with epidermal growth factor (EGF) caused increased expression of miR-21 and inhibition of AR prevented it. Further, AR inhibition also increased PDCD4, a putative target of miR-21 in human colon cancer cells. Inhibition of AR also prevented EGF-induced phosphorylation of PDCD4. Treatment of HT29 cells with AR inhibitor, fidarestat, prevented the EGF-induced phosphorylation of mammalian target of rapamycin (mTOR), regulatory associated protein of mTOR (Raptor), eukaryotic initiation factor 4E (eIF4E), p70 S6 kinase (S6K) and eukaryotic initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) and increased the phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK). Similarly, in nude mice xenograft tissues, PDCD4 and 4E-BP1 levels were significantly higher in AR inhibitor-treated mice compared to controls. Collectively, these results indicate that AR inhibition prevents growth factor-induced colon cancer growth by down-regulating miR-21 expression and increasing PDCD4 levels through the reactive oxygen species (ROS)/AMPK/mTOR/AP1/4E-BP1 pathway.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23824282,"Year":2013,"Title":"Deep Sequencing the MicroRNA Transcriptome in Colorectal Cancer.","Abstract":"Colorectal cancer (CRC) is one of the leading causes of cancer related deaths and the search for prognostic biomarkers that might improve treatment decisions is warranted. MicroRNAs (miRNAs) are short non-coding RNA molecules involved in regulating gene expression and have been proposed as possible biomarkers in CRC. In order to characterize the miRNA transcriptome, a large cohort including 88 CRC tumors with long-term follow-up was deep sequenced. 523 mature miRNAs were expressed in our cohort, and they exhibited largely uniform expression patterns across tumor samples. Few associations were found between clinical parameters and miRNA expression, among them, low expression of miR-592 and high expression of miR-10b-5p and miR-615-3p were associated with tumors located in the right colon relative to the left colon and rectum. High expression of miR-615-3p was also associated with poorly differentiated tumors. No prognostic biomarker candidates for overall and metastasis-free survival were identified by applying the LASSO method in a Cox proportional hazards model or univariate Cox. Examination of the five most abundantly expressed miRNAs in the cohort (miR-10a-5p, miR-21-5p, miR-22-3p, miR-143-3p and miR-192-5p) revealed that their collective expression represented 54% of the detected miRNA sequences. Pathway analysis of the target genes regulated by the five most highly expressed miRNAs uncovered a significant number of genes involved in the CRC pathway, including APC, TGFbeta and PI3K, thus suggesting that these miRNAs are relevant in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23817679,"Year":2013,"Title":"miR-21 and its target gene CCL20 are both highly overexpressed in the microenvironment of colorectal tumors: significance of their regulation.","Abstract":"Recently, we reported a functional interaction between miR-21 and its identified chemokine target CCL20 in colorectal cancer (CRC) cell lines. Here, we investigated whether such functional interactions are permitted at the cellular level which would require an inverse correlation of expression and also co-expression of miR-21 and CCL20 in the same cell. Expression profiling was performed using qPCR, and ELISA, in situ hybridization and immunohistochemistry were applied for the presentation of their cellular localization. We demonstrated that miR-21 as well as CCL20 were both significantly upregulated in CRC tissues; thus, showing no antidromic expression pattern. This provided an initial clue that miR-21 and CCL20 may not be expressed in the same cell. In addition, we located miR-21 expression at the cellular level predominantly in stromal cells such as tumor-associated fibroblasts and to a minor degree in immune cells such as macrophages and lymphocytes. Likewise, CCL20 expression was primarily detected in tumor-infiltrating immune cells. Thus, investigating the cellular localization of miR-21 and its target CCL20 revealed that both molecules are expressed predominantly in the microenvironment of CRC tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23788041,"Year":2013,"Title":"Pleiotropic actions of miR-21 highlight the critical role of deregulated stromal microRNAs during colorectal cancer progression.","Abstract":"The oncogene microRNA-21 (miRNA; miR-21) is overexpressed in most solid organ tumours; however, a recent examination of stage II colorectal cancer (CRC) specimens suggests this may be a stromal phenomenon and not only a feature of cancer cells. In vitro and in vivo studies show that miR-21 has potent pro-metastatic effects in various malignant carcinoma cell lines. The tumour microenvironment has also been identified as a key actor during the metastatic cascade; however to date the significance of deregulated miR-21 expression within the cancer-associated stroma has not been examined. In the present study, a quantitative RT-PCR-based analysis of laser microdissected tissue confirmed that miR-21 expression is associated with a four-fold mean increase in CRC stroma compared with normal tissue. In situ hybridisation using locked nucleic acid probes localised miR-21 expression predominantly to fibroblasts within tumour-associated stroma. To study the molecular and biological impact of deregulated stromal miR-21 in CRC, stable ectopic expression was induced in immortalised fibroblasts. This resulted in upregulated alpha-smooth muscle actin expression implying miR-21 overexpression is driving the fibroblast-to-myofibroblast transdifferentiation. Conditioned medium from miR-21-overexpressing fibroblasts protected CRC cells from oxaliplatin-induced apoptosis and increased their proliferative capacity. 3D organotypic co-cultures containing fibroblasts and CRC cells revealed that ectopic stromal miR-21 expression was associated with increased epithelial invasiveness. Reversion-inducing cysteine-rich protein with kazal motifs, an inhibitor of matrix-remodelling enzyme MMP2, was significantly downregulated by ectopic miR-21 in established and primary colorectal fibroblasts with a reciprocal rise in MMP2 activity. Inhibition of MMP2 abrogated the invasion-promoting effects of ectopic miR-21. This data, which characterises a novel pro-metastatic mechanism mediated by miR-21 in the CRC stroma, highlights the importance of miRNA deregulation within the tumour microenvironment and identifies a potential application for stromal miRNAs as biomarkers in cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23773491,"Year":2013,"Title":"The prognostic significance of APC gene mutation and miR-21 expression in advanced-stage colorectal cancer.","Abstract":"AIM: Colorectal cancer (CRC) is the second commonest cause of cancer death in Taiwan. Although numerous genes have been associated with tumorigenesis in colorectal cancer, only a few have been validated and used as biomarkers for predicting clinical outcome. The aim of this study was to analyse the association of APC gene mutation and miR-21 expression with clinical outcome in CRC patients. METHOD: In total, 195 colorectal cancer patients were enrolled in a single medical centre between 2003 and 2007. APC gene mutation and expression of APC and miR-21 were analysed by direct DNA sequencing and real-time reverse transcription polymerase chain reaction. The primary outcome included 5-year overall survival and univariate (Kaplan-Meier) and multivariate (Cox regression) analyses of prognostic factors. RESULTS: The results showed that 66 (33.8%) of 195 tumour tissues contained an APC mutation. The predominant APC gene variations were deletion mutations (50.0%). APC gene expression was low in CRC and negatively correlated with miR-21 expression and gene mutation. In advanced-stage cancer, patients with APC mutation/high miR-21 had poorer overall survival rates than those with APC mutation/low miR-21, APC wild-type/high miR-21 and APC wild-type/low miR-21. CONCLUSION: In Taiwan, downregulation of the APC gene in CRC correlated with gene mutation and miR-21 upregulation. APC mutation and miR-21 expression could be used to predict the clinical outcome of CRC, especially in patients with advanced disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23741026,"Year":2013,"Title":"Diagnostic microRNA markers to screen for sporadic human colon cancer in stool: I. Proof of principle.","Abstract":"To present proof-of-principle application for employing micro(mi)RNAs as diagnostic markers for colon cancer, we carried out global microarray expression studies on stool samples obtained from fifteen individuals (three controls, and three each with TNM stage 0-1, stage 2, stage 3, and stage 4 colon cancer), using Affymetrix GeneChip miRNA 3.0 Array, to select for a panel of miRNA genes for subsequent focused semi-quantitative polymerase chain reaction (PCR) analysis studies. Microarray results showed 202 preferentially expressed miRNA genes that were either increased (141 miRNAs), or reduced (61 miRNAs) in expression. We then conducted a stem-loop reverse transcriptase (RT)-TaqMan(R) minor groove binding (MGB) probes, followed by a modified qPCR expression study on 20 selected miRNAs. Twelve of the miRNAs exhibited increased and 8 decreased expression in stool from 60 individuals (20 controls, 20 with tumor-lymph node-metastatic (TNM) stage 0-1, 10 with stage 2, five with stage 3, and 5 with stage 4 colon cancer) to quantitatively monitor miRNA changes at various TNM stages of colon cancer progression. We also used laser-capture microdissection (LCM) of colon mucosal epithelial tissue samples (three control samples, and three samples from each of the four stages of colon cancer, for a total of 15 samples) to find concordance or lack thereof with stool findings. The reference housekeeping pseudogene-free ribosomal gene (18S rRNA), which shows little variation in expression, was employed as a normalization standard for relative PCR quantification. Results of the PCR analyses confirmed that twelve miRNAs (miR-7, miR-17, miR-20a, miR-21, miR-92a, miR-96, miR-106a, miR-134, miR-183, miR-196a, miR-199a-3p and miR214) had an increased expression in the stool of patients with colon cancer, and that later TNM carcinoma stages exhibited a more pronounced expression than did adenomas. On the other hand, eight miRNAs (miR-9, miR-29b, miR-127-5p, miR-138, miR-143, miR-146a, miR-222 and miR-938) had decreased expression in the stool of patients with colon cancer, which was also more pronounced from early to later TNM stages. Results from colon mucosal tissues were similar to those from stool samples, although with more apparent changes in expression. Cytological studies on purified stool colonocytes that employed Giemsa staining showed 80% sensitivity for detecting tumor cells in stool smears. The performance characteristics of the test confirmed that stool is a medium well-suited for colon cancer screening, and that the quantitative changes in the expression of few mature miRNA molecules in stool associated with colon cancer progression provided for more sensitive and specific non-invasive diagnostic markers than tests currently available on the market. Thus, a larger prospective and properly randomized validation study of control individuals and patients exhibiting various stages of colon cancer progression (TNM stages 0-IV) is now needed in order to standardize test conditions, and provide a means for determining the true sensitivity and specificity of a miRNA screening approach in stool for the non-invasive detection of colon cancer, particularly at an early stage (0-I). Eventually, we will develop a chip to enhance molecular screening for colon cancer, as has been accomplished for the detection of genetically-modified organisms (GMOs) in foods.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23719259,"Year":2013,"Title":"The prognostic value of microRNAs varies with patient race/ethnicity and stage of colorectal cancer.","Abstract":"PURPOSE: MicroRNAs (miRNA) have potential prognostic value for colorectal cancers; however, their value based on patient race/ethnicity and pathologic stage has not been determined. The goal was to ascertain the prognostic value of 5 miRNAs with increased expression in colorectal cancers of African American (black) and non-Hispanic Caucasian (white) patients. EXPERIMENTAL DESIGN: TaqMan quantitative real-time PCR was used to quantify expression of miR-20a, miR-21, miR-106a, miR-181b, and miR-203 in paired normal and tumor colorectal cancer archival tissues collected from 106 black and 239 white patients. The results were correlated with overall survival based on patient race/ethnicity and pathologic stage. Because decisions about adjuvant therapy are important for stage III colorectal cancers, and because miR-181b seemed to have prognostic value only for stage III black patients, we assessed its prognostic value in a separate cohort of 36 stage III colorectal cancers of blacks. RESULTS: All 5 miRNAs had higher expression in colorectal cancers (>1.0-fold) than in corresponding normal tissues. High expression of miR-203 was associated with poor survival of whites with stage IV colorectal cancers (HR = 3.00; 95% CI, 1.29-7.53), but in blacks it was an indicator of poor survival of patients with stages I and II colorectal cancers (HR = 5.63; 95% CI, 1.03-30.64). Increased miR-21 expression correlated with poor prognosis for white stage IV patients (HR = 2.50; 95% CI, 1.07-5.83). In both test and validation cohorts, high miR-181b expression correlated with poor survival of only black patients with stage III colorectal cancers (HR = 1.94; 95% CI, 1.03-3.67). CONCLUSION: These preliminary findings suggest that the prognostic value of miRNAs in colorectal cancers varies with patient race/ethnicity and stage of disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23704278,"Year":2013,"Title":"Serum miR-21 as a diagnostic and prognostic biomarker in colorectal cancer.","Abstract":"BACKGROUND: The oncogenic microRNAs (miRNAs) miR-21 and miR-31 negatively regulate tumor-suppressor genes. Their potential as serum biomarkers has not been determined in human colorectal cancer (CRC). METHODS: To determine whether miR-21 and miR-31 are secretory miRNAs, we screened expression in medium from 2 CRC cell lines, which was followed by serum analysis from 12 CRC patients and 12 control subjects. We validated expression of candidate miRNAs in serum samples from an independent cohort of 186 CRC patients, 60 postoperative patients, 43 advanced adenoma patients, and 53 control subjects. We analyzed miR-21 expression in 166 matched primary CRC tissues to determine whether serum miRNAs reflect expression in CRC. Patient survival analyses were performed by Kaplan-Meier analyses and Cox regression models. All statistical tests were two-sided. RESULTS: Although miR-21 was secreted from CRC cell lines and upregulated in serum of CRC patients, no statistically significant differences were observed in serum miR-31 expression between CRC patients and control subjects. In the validation cohort, miR-21 levels were statistically significantly elevated in preoperative serum from patients with adenomas (P < .001) and CRCs (P < .001). Importantly, miR-21 expression dropped in postoperative serum from patients who underwent curative surgery (P < .001). Serum miR-21 levels robustly distinguished adenoma (area under the curve [AUC] = 0.813; 95% confidence interval [CI] = 0.691 to 0.910) and CRC (AUC = 0.919; 95% CI = 0.867 to 0.958) patients from control subjects. High miR-21 expression in serum and tissue was statistically significantly associated with tumor size, distant metastasis, and poor survival. Moreover, serum miR-21 was an independent prognostic marker for CRC (hazard ratio = 4.12; 95% CI = 1.10 to 15.4; P = .03). CONCLUSIONS: Serum miR-21 is a promising biomarker for the early detection and prognosis of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23690963,"Year":2013,"Title":"Identification and evaluation of plasma microRNAs for early detection of colorectal cancer.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the most commonly diagnosed cancers. Circulating microRNAs (miRNAs) have been suggested as potentially promising markers for early detection of CRC. We aimed to identify and evaluate a panel of miRNAs that might be suitable for CRC early detection. METHODS: MiRNAs were profiled by TaqMan MicroRNA Array and screened for differential expression in 5 pools of plasma samples of CRC patients (N = 50) and 5 pools of neoplasm-free controls (N = 50). Additional miRNAs were selected from a literature review. Identified candidates were evaluated in independent validation samples with respect to discrimination of CRC patients (N = 80) or advanced adenoma patients (N = 50) and neoplasm-free controls (N = 194). Diagnostic performance of the panel of miRNAs was assessed by multiple logistic regression, using bootstrap analysis to correct for over-optimism. RESULTS: Five miRNAs identified to be differentially expressed from TaqMan MicroRNA Array (miR-29a, -106b, -133a, -342-3p, -532-3p), and seven miRNAs reported to be differentially expressed in the literature (miR-18a, -20a, -21, -92a, -143, -145, -181b) were selected for validation. Nine of the twelve miRNAs (miR-18a, -20a, -21, -29a, -92a, -106b, -133a, -143, -145) were found to be differentially expressed in CRC patients and controls in the validation samples. The optimism-corrected area under the curve was 0.745 (95% confidence interval: 0.708-0.846). None of the selected miRNAs showed significant differential expression between advanced adenoma patients and neoplasm-free controls. CONCLUSION: The identified panel of miRNAs could be of potential use in the development of a multi-marker blood based test for early detection of CRC. IMPACT: The study underscores the high potential of plasma miRNAs for the improvement of current offers of non-invasive CRC screening.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23673725,"Year":2013,"Title":"microRNA expression profile in stage III colorectal cancer: circulating miR-18a and miR-29a as promising biomarkers.","Abstract":"Biomarkers that can facilitate disease detection, staging and prediction of outcome are highly desirable to improve survival and to help determine optimized treatment for colorectal cancer patients. microRNAs (miRNAs) are small non-coding RNAs that play a crucial role in gene regulatory networks. The deregulation of miRNA expression has been found in several types of cancer and may represent a novel class of cancer biomarkers. Our aim was to determine the miRNA signature of stage III colorectal cancer (CRC) tumors and to identify potential circulating miRNAs that may represent non-invasive biomarkers in CRC patients. Genome-wide microarray analysis of miRNA expression was performed on 12 paired tumor and non-tumor formalin-fixed paraffin-embedded tissues from stage III CRC patients. A selection of differentially overexpressed miRNAs was validated by quantitative real-time polymerase chain reaction (qRT-PCR) and determined in the serum of a set of 56 individuals (30 stage III CRC patients and 26 healthy individuals). Using 1.5-fold expression difference as a cut-off level, 43 miRNAs were identified as differentially expressed in tumor versus normal tissue. Using reverse transcription and qRT-PCR, 11 miRNAs (miR-135b, miR-141, miR-18a, miR-20a, miR-21, miR-224, miR-29a, miR-31, miR-34a, miR-92a and miR-96) were confirmed as significantly overexpressed in tumor samples when compared with normal samples. We were able to detect 9 of these 11 miRNAs in serum samples from CRC patients and healthy individuals. Serum levels of miR-18a and miR-29a were significantly higher in CRC patients when compared to levels in the controls (p<0.05). In conclusion, this study identified a substantial number of miRNAs which were differentially expressed in stage III colorectal tumors. Moreover, the findings provide relevant information concerning overexpressed tumoral miRNAs as potential circulating biomarkers and highlight serum miR-18a and miR-29a as promising biomarkers for the screening and monitoring of CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23625654,"Year":2013,"Title":"Serum miR-21 and miR-92a as biomarkers in the diagnosis and prognosis of colorectal cancer.","Abstract":"Previous studies from our laboratory identified a number of miRNAs that were aberrantly expressed in colorectal cancer (CRC) tissue. However, their diagnostic and prognostic value in serum has not been fully evaluated. In the present study, we measured the levels of five miRNAs (miR-21, miR-31, miR-92a, miR-18a, and miR-106a) in serum samples from 200 CRC patients, 50 advanced adenoma patients, and 80 healthy controls by real-time quantitative polymerase chain reaction (RT-PCR). In our study, the levels of miR-21 and miR-92a in patients with CRC and advanced adenoma were significantly higher than those in healthy controls (all P < 0.05). MiR-21 yielded an area under the receiver-operating characteristics (ROC) curve (AUC) of 0.802 and miR-92a yielded an AUC of 0.786 in discriminating CRCs from the controls. Additionally, miR-21 and miR-92a yielded an AUC of 0.709 and 0.701, respectively, in discriminating advanced adenomas from the controls. Combined ROC analyses using both miRNAs, revealed an elevated AUC of 0.847 in discriminating CRCs, and an AUC of 0.722 in discriminating advanced adenomas from the controls. In the multivariate Cox proportional hazards analysis, high miR-92a expression in CRC was independently associated with poor survival (P = 0.03; hazard ratio 4.36; 95 % confidence interval = 1.64-11.57). No significant difference was observed in the levels of miR-18a, miR-31, and miR-106a among CRC, advanced adenoma, and control samples. In summary, our data indicate that miR-21 and miR-92a serum levels have potential value for early detection of CRC. Furthermore, miR-92a has prognostic value in CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23544170,"Year":2013,"Title":"Down-regulation of miR-21 Induces Differentiation of Chemoresistant Colon Cancer Cells and Enhances Susceptibility to Therapeutic Regimens.","Abstract":"MicroRNAs are endogenous posttranscriptional modulators that negatively control the expression of their target genes and play an important role in the development and progression of many malignancies, including colorectal carcinoma. In particular, expression of microRNA-21 (miR-21) is greatly increased in chemotherapy-resistant (CR) colon cancer cells that are enriched in undifferentiated cancer stem/stem-like cells (CSCs/CSLCs). We hypothesize that miR-21 plays a critical role in regulating differentiation of CR colon cancer cells. Indeed, we observed that downregulation of miR-21 in CR colon cancer cells (HCT-116 or HT-29) by antisense miR-21 induced differentiation, as evidenced by marked increases in cytokeratin-20 (CK-20) expression and alkaline phosphatase activity. These changes were accompanied by a significant reduction in the expression of colon CSC/CSLC marker CD44, colonosphere formation, and T-cell factor/lymphoid enhancer factor (TCF/LEF) activity but increased the expression of proapoptotic programmed cell death 4 gene. Induction of differentiation greatly increased sensitivity of CR colon cancer cells to the growth inhibitory properties of all three regimens tested: 5-fluorouracil + oxaliplatin (FUOX), difluorinated curcumin (CDF), and the combination of CDF and FUOX. However, the magnitude of inhibition of growth by either CDF (75%) alone or CDF + FUOX (80%) was much higher than that observed with only FUOX (40%). Growth inhibition by CDF and CDF + FUOX in differentiating CR colon cancer cells was associated with a 98% to 99% reduction in the expression of CD44 and epidermal growth factor receptor (EGFR). However, down-regulation of CK-20 in CR colon cancer cells produced no significant change in cellular growth in the absence or presence of FUOX, when compared with the corresponding controls. The current observation suggests that CDF and CDF + FUOX are highly effective in inhibiting growth and reducing colon CSCs/CSLCs in anti-miR-21-induced differentiating CR colon cancer cells and supports our contention that differentiation enhances susceptibility of CR cancer cells to conventional and nonconventional therapeutic regimen.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23533633,"Year":2013,"Title":"CD24 induces expression of the oncomir miR-21 via Src, and CD24 and Src are both post-transcriptionally downregulated by the tumor suppressor miR-34a.","Abstract":"Cancer is a complex disease process that evolves as a consequence of multiple malfunctions in key regulatory molecular networks. Understanding these networks will be essential to combat cancer. In this study, we focussed on central players in such networks. In a series of colon and breast cancer cell lines, we found that CD24 activates Src, and induces the activation of c-Jun and expression of c-Jun and c-Fos. Thereby CD24 increases the promoter activity and expression of miR-21, which in turn suppresses expression of Pdcd4 and PTEN. Co-transfection of a CD24 expression construct and an siRNA that silences Src showed that CD24-dependent upregulation of miR-21 is mediated by Src. Additionally, we found that miR-34a post-transcriptionally downregulates CD24 and Src expression, leading to the deactivation of c-Jun, reduced expression of c-Jun and c-Fos, inhibition of miR-21, and upregulation of Pdcd4 and PTEN. Furthermore, miR-34a-mediated inhibition of Src expression reduced migration and invasion of colorectal cancer cells. Resected tumor tissues from 26 colorectal patients showed significantly lower expression of Pdcd4 and miR-34a, and higher expression of CD24, Src and miR-21 compared to the corresponding normal tissues. Moreover, CD24 positively correlated with the amount of Src protein in tumor tissues, and a trend towards an inverse correlation between miR-34a and Src protein levels was also observed. Our results reveal essential players in the complex networks that regulate the progression of solid tumors such as colorectal cancer. These findings therefore identify novel therapeutic approaches for combating tumor growth and progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23526568,"Year":2015,"Title":"MicroRNA-195 chemosensitizes colon cancer cells to the chemotherapeutic drug doxorubicin by targeting the first binding site of BCL2L2 mRNA.","Abstract":"The mechanisms underlying doxorubicin (Dox) resistance in colon cancer cells are not fully understood. MicroRNA (miRNA) play important roles in tumorigenesis and drug resistance. However, the relationship between miRNA and Dox resistance in colon cancer cells has not been previously explored. In this study, we utilized microRNA array and real-time PCR to verify that miR-127, miR-195, miR-22, miR-137 were significantly down-regulated, while miR-21, miR-592 were up-regulated in both HT29/DOX and LOVO/DOX cell lines. In vitro cell viability assay showed that knockdown of miR-195 in HT29 and LOVO cells caused a marked inhibition of Dox-induced cytotoxicity. Moreover, we explored that miR-195 is involved in repression of BCL2L2 expression through targeting its 3'-untranslated region, especially the first binding site within its mRNA. Furthermore, down-regulation of miR-195 conferred DOX resistance in parental cells and reduced cell apoptosis activity, while over-expression of miR-195 sensitized resistant cells to DOX and enhanced cell apoptosis activity, all of which can be partly rescued by BCL2L2 siRNA and cDNA expression. These results may have implications for therapeutic strategies aiming to overcome colon cancer cell resistance to Dox.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23477554,"Year":2013,"Title":"Blood-based miRNAs as noninvasive diagnostic and surrogative biomarkers in colorectal cancer.","Abstract":"Few studies have assessed circulating miRNAs in the blood of colorectal cancer (CRC) patients. In the evaluated article, Kanaan et al. demonstrated that miR-21 may be a promising diagnostic plasma biomarker for CRC. They assessed miRNAs dysregulated in both tissue and blood samples from patients with CRC. A high-throughput microarray was used to first detect miRNAs deregulated in CRC compared with adjacent normal tissue. The three most upregulated and downregulated miRNAs were then measured in blood samples. Plasma miR-21 was able to correctly identify CRC with 90% specificity and sensitivity. In this article, we have considered the use of miRNAs as blood-based biomarkers for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23288924,"Year":2013,"Title":"Overexpression of microRNAs-155 and 21 targeting mismatch repair proteins in inflammatory bowel diseases.","Abstract":"Microsatellite instability (MSI) due to mismatch repair (MMR) deficiency is reported in 5-10% of colorectal cancers (CRCs) complicating inflammatory bowel diseases (IBD). The molecular mechanisms underlying MMR deficiency may be different in IBD CRCs, and in sporadic and hereditary MSI tumors. Here, we hypothesize that overexpression of miR-155 and miR-21, two inflammation-related microRNAs that target core MMR proteins, may constitute a pre-neoplastic event for the development of MSI IBD CRCs. We studied miR-155 and miR-21 expression using real-time quantitative PCR in MSI (n = 10) and microsatellite stable (n = 10) IBD CRCs, and in MSI (n = 32) and microsatellite stable (n = 30) non-IBD CRCs. We also screened colonic samples from IBD patients without cancer (n = 18) and used healthy colonic mucosa as controls (n = 20). MiR-155 and miR-21 appeared significantly overexpressed not only in the colonic mucosa of IBD subjects without CRC but also in neoplastic tissues of IBD patients compared with non-IBD controls (P < 0.001). Importantly, in patients with IBD CRCs, miR-155 and miR-21 overexpression extended to the distant non-neoplastic mucosa (P < 0.001). Ratios of expressions in tumors versus matched distant mucosa revealed a nearly significant association between miR-155 overexpression and MSI in IBDs (P = 0.057). These results show a strong deregulation of both MMR-targeting microRNAs in IBD subjects with or without cancer. MiR-155 overexpression being particularly associated to MSI IBD CRCs and extending to distant non-neoplastic mucosa, strongly suggests that a pre-neoplastic miR-155 field defect may promote MSI-driven transformation of the colonic mucosa. The detection and monitoring of miR-155 field defect may, therefore, have implications for the prevention and treatment of MSI IBD CRCs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23224068,"Year":2013,"Title":"PDCD4/miR-21 dysregulation in inflammatory bowel disease-associated carcinogenesis.","Abstract":"Inflammatory bowel diseases (IBDs; both ulcerative colitis [UC] and Crohn's colitis [CC]) are well-established predisposing pathological conditions for colorectal cancer (CRC) development. In IBDs, both the endoscopy and the histology assessment of CRC precursors (i.e., dysplasia, also defined as intraepithelial neoplasia) are associated with low interobserver consistency, and no reliable dysplasia-specific biomarker is available. The programmed cell death 4 (PDCD4) tumor suppressor gene is involved in sporadic colorectal oncogenesis, but scanty information is available on its involvement in IBD-associated colorectal oncogenesis. One hundred twenty tissue samples representative of active and inactive IBD and of flat dysplasia were obtained from 30 cases of UC and 30 of CC who undergone colectomy. Twenty additional biopsy samples obtained from patients with irritable bowel syndrome acted as normal controls. PDCD4 expression was assessed by immunohistochemistry; the expression of miR-21 (a major PDCD4 regulator) was investigated by quantitative real-time PCR and in situ hybridization in different series of a hundred samples. Tissue specimens from both controls and inactive IBD consistently featured strong PDCD4 nuclear immunostain; conversely, lower PDCD4 nuclear expression was featured by both active IBD and IBD-associated dysplastic lesions. Significant PDCD4 down-regulation distinguished IBD-associated dysplasia (p < 0.001) versus active IBD. In both active IBD and dysplasia, PDCD4 down-regulation was significantly associated with miR-21 up-regulation. PDCD4 nuclear down-regulation (which parallels miR-21 up-regulation) is involved in the molecular pathway of IBD-associated carcinogenesis. PDCD4 nuclear expression may be usefully applied as ancillary maker in the histological assessment of IBD-associated dysplastic lesions.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23174819,"Year":2013,"Title":"MiR-21 regulates biological behavior through the PTEN/PI-3 K/Akt signaling pathway in human colorectal cancer cells.","Abstract":"The aim of this study was to determine a role of microRNA-21 (miR-21) in colorectal cancer (CRC) and to elucidate the regulation of phosphatase and tensin homologue (PTEN) gene by miR-21. MiR-21 expression was investigated in 30 CRC samples and five CRC cell lines. In this study, we show that the expression of miR-21 was overexpressed in CRC compared with adenomas and normal tissues. Patients with poor differentiation, lymph node metastasis and advanced TNM stage showed significantly high expression of miR-21. Inhibition of miR-21 in the HCT116 cell line reduced cellular proliferation, migration and invasion, induced apoptosis and inhibited cell cycle progression. The PTEN protein levels in CRC tissues and cells had an inverse correlation with miR-21 expression. Anti-miR-21-transfected cells increased PTEN protein expression without changing the PTEN mRNA level and increased a luciferase-reporter activity. MiR-21 targets PTEN at the post-transcriptional level and regulates cell proliferation and invasion in CRC. It may serve as a novel therapeutic target in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23121918,"Year":2012,"Title":"Clinical relevance of microRNA miR-21, miR-31, miR-92a, miR-101, miR-106a and miR-145 in colorectal cancer.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) regulate gene expression by binding to mRNA, and can function as oncogenes or tumor suppressors depending on the target. In this study, using qRT-PCR, we examined the expression of six miRNAs (miR-21, miR-31, miR-92a, miR-101, miR-106a and miR-145) in tumors from 193 prospectively recruited patients with colorectal cancer, and associations with clinicopathological parameters and patient outcome were analyzed. The miRNAs were chosen based on previous studies for their biomarker potential and suggested biological relevance in colorectal cancer. METHODS: The miRNA expression was examined by qRT-PCR. Associations between miRNA expression and clinicopathological variables were explored using Mann-Whitney U and Kruskal-Wallis test while survival was estimated using the Kaplan-Meier method and compared using the log-rank test. RESULTS: MiR-101 was hardly expressed in the tumor samples, while for the other miRNAs, variable expression levels and expression ranges were observed, with miR-21 being most abundantly expressed relative to the reference (RNU44). In our study cohort, major clinical significance was demonstrated only for miR-31, as high expression was associated with advanced tumor stage and poor differentiation. No significant associations were found between expression of the investigated miRNAs and metastasis-free or overall survival. CONCLUSIONS: Investigating the expression of six miRNAs previously identified as candidate biomarkers in colorectal cancer, few clinically relevant associations were detected in our patient cohort. Our results emphasize the importance of validating potential tumor markers in independent patient cohorts, and indicate that the role of miRNAs as colorectal cancer biomarkers is still undetermined.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23055106,"Year":2013,"Title":"Isolation and characterization of calcium sensing receptor null cells: a highly malignant and drug resistant phenotype of colon cancer.","Abstract":"The expression of calcium sensing receptor (CaSR) in the human colonic crypt epithelium is linked to cellular differentiation while its lack of expression is associated with undifferentiated and invasive colon carcinoma. Human colon carcinoma cell lines contain small subpopulations (10-20%) that do not express CaSR (termed CaSR null cells). Here, we report on the isolation, propagation, maintenance and characterization of CaSR null cells from the CBS and HCT116 human colon carcinoma cell lines. CaSR null cells grew as three-dimensional non-adherent spherical clusters with increased propensity for anchorage independent growth, cellular proliferation and invasion of matrigels. CaSR null cells were highly resistant to fluorouracil and expressed abundant amount of thymidylate synthase and survivin. Molecular profiling by real time reverse transcription-polymerase chain reaction (RT-PCR) and Western blots showed a high level of expression of the previously reported cancer stem cell markers CD133, CD44 and Nanog in CaSR null cells. A significant increase in the expression of epithelial-mesenchymal transitional molecules and transcription factors was also observed. These include N-cadherin, beta-catenin, vimentin, fibronectin, Snail1, Snail2, Twist and FOXC2. The expression of the tumor suppressive E-cadherin and miR145, on the other hand, was greatly reduced while expression of the oncogenic microRNAs: miR21, miR135a and miR135b was significantly up-regulated. CaSR null cells possess a myriad of cellular and molecular features that drive and sustain the malignant phenotype. We conclude that CaSR null constitutes a highly malignant and drug resistant phenotype of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":23011541,"Year":2012,"Title":"The prognostic importance of miR-21 in stage II colon cancer: a population-based study.","Abstract":"BACKGROUND: Despite several years of research and attempts to develop prognostic models a considerable fraction of stage II colon cancer patients will experience relapse within few years from their operation. The aim of the present study was to investigate the prognostic importance of miRNA-21 (miR-21), quantified by in situ hybridisation, in a unique, large population-based cohort. PATIENTS AND METHODS: The study included 764 patients diagnosed with stage II colon cancer in Denmark in the year 2003. One section from a representative paraffin-embedded tumour tissue specimen from each patient was processed for analysis of miR-21 and quantitatively assessed by image analysis. RESULTS: The miR-21 signal was predominantly observed in fibroblast-like cells located in the stromal compartment of the tumours. We found that patients expressing high levels of miR-21 had significantly inferior recurrence-free cancer-specific survival (RF-CSS): HR=1.26; 95% CI: 1.15-1.60; P<0.001. In Cox regression analysis, a high level of miR-21 retained its prognostic importance and was found to be significantly related to poor RF-CSS: HR=1.41; 95% CI: 1.19-1.67; P<0.001. CONCLUSION: The present study showed that increasing miR-21 expression levels were significantly correlated to decreasing RF-CSS. Further investigations of the clinical importance of miR-21 in the selection of high-risk stage II colon cancer patients are merited.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22978663,"Year":2013,"Title":"Aldose reductase inhibition prevents colon cancer growth by restoring phosphatase and tensin homolog through modulation of miR-21 and FOXO3a.","Abstract":"AIMS: We have shown earlier that inhibition of aldose reductase (AR), an oxidative stress-response protein, prevents colon cancer cell growth in vitro and in vivo. Changes in microribonucleic acid (miR) expression can contribute to cancer by modulating the functional expression of critical genes involved in cancer growth and metastasis. However, the molecular mechanisms by which AR regulates miR expression and their dependent mitogenic effects in cancer cells are not known. Therefore, we investigated how AR regulates growth factor-induced expression of miRs and growth of colon cancer cells. RESULTS: Inhibition of AR significantly downregulated growth factor-induced miR-21 expression in human colon cancer cells, HT29, SW480, and Caco-2. Further, AR inhibition also increased phosphatase and tensin homolog (PTEN) (a direct target of miR-21) and forkhead box O3A (FOXO3a) in colon cancer cells. Our results obtained with HT29 cells ablated with FOXO3a siRNA showed increased activator protein-1 (AP-1) activation and miR-21 expression, indicating that FOXO3a represses miR-21 via AP-1 inactivation. Inhibition of AR also prevented the epidermal growth factor-induced phosphorylation of phosphatidylinositol 3-kinase (PI3K), serine/threonine kinase (AKT), c-Jun, c-Fos, PTEN, and FOXO3a, and deoxyribonucleic acid (DNA)-binding activity of AP-1. More importantly, in human colon adenocarcinoma xenograft tissues, miR-21 expression was lower, and PTEN and FOXO3a levels were significantly higher in AR inhibitor-treated mice compared to controls. INNOVATION: These findings demonstrate a novel role of AR in the regulation of miR-21 and its target PTEN in growth factor-induced colon cancer cell growth. CONCLUSIONS: Collectively, these results show a novel role of AR in mediation of growth factor-induced colon cancer growth by modulating miR-21, PTEN, and FOXO3a expression through reactive oxygen species (ROS)/PI3K/AKT/AP-1.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22895844,"Year":2012,"Title":"Exosomes secreted from human colorectal cancer cell lines contain mRNAs, microRNAs and natural antisense RNAs, that can transfer into the human hepatoma HepG2 and lung cancer A549 cell lines.","Abstract":"Exosomes are microvesicles that are released from various cells into the extracellular space. It has been reported that the components within exosomes vary according to the type of secreted cell. In the present study, we investigated the tetraspanin family proteins CD63, CD9 and CD81 as useful collection markers of exosomes derived from the three colorectal cancer (CRC) cell lines HCT-15, SW480 and WiDr. In addition, we aimed to detect the mRNAs, microRNAs and natural antisense RNAs within the exosomes secreted from the three CRC cell lines. Furthermore, we examined whether exosomes containing their RNAs were transferred into the hepatoma cell line HepG2 and lung cancer cell line A549. CD81 was detected in exosomes secreted from the three CRC cell lines. This result indicates that CD81 can be a collection marker of exosomes derived from the three CRC cell lines. When the RNA species within exosomes derived from the three CRC cell lines were examined, the mRNAs of housekeeping genes such as ACTB and GAPDH, the microRNAs such as miR-21, miR-192 and miR-221, and the natural antisense RNAs of LRRC24, MDM2 and CDKN1A genes, were detected. We discovered their natural antisense RNAs within exosomes for the first time in the present study. Furthermore, PKH67-labeled exosomes derived from the CRC cell lines were taken up into HepG2 and A549 cells. These findings indicate that the intracellular RNAs enclosed within exosomes are secreted to the outside, and exosomes derived from the CRC cell lines are transferred into HepG2 and A549 cells. In conclusion, we reveal that exosomes derived from the CRC cell lines contain mRNAs, microRNAs and natural antisense RNAs, and can be delivered into HepG2 and A549 cells. These findings indicate that exosomal RNAs can shuttle between cells, and may be involved in the regulation of gene expression in recipient cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22868372,"Year":2012,"Title":"Plasma miR-21: a potential diagnostic marker of colorectal cancer.","Abstract":"OBJECTIVES: The main objective of this study was to investigate the potential use of circulating microRNAs (miRNAs) as biomarkers of sporadic colorectal cancer (CRC). BACKGROUND: CRC, a leading cause of death, is curable if detected early. There is an unmet need for an accurate, noninvasive biomarker of CRC. MiRNAs are non-protein-coding RNAs regulating gene expression that play a role in CRC development. METHODS: Levels of 380 miRNAs were determined using microfluidic array technology (Applied Biosystems) in a \"training\" set of 30 CRC patients from whom cancer and adjacent normal tissue were collected. The 4 most dysregulated miRNAs (P < 0.05, false discovery rate (FDR): 10%) were then validated in a second blinded \"test\" set of 16 CRC patients from whom cancer and normal adjacent tissue had been collected. Validated tissue miRNAs were then evaluated in a plasma \"test\" set consisting of 30 CRC patients and 30 individuals without CRC. The most dysregulated tissue miRNAs were then validated in an independent new plasma test set consisting of 20 CRC patients with 20 age-, -, and race-matched subjects without CRC. RESULTS: Nineteen of 380 miRNAs were dysregulated in CRC tissue in the tissue \"training\" set (P < 0.05, FDR: 10%). The 2 most upregulated (miR-31; miR-135b) and most downregulated (miR-1; miR-133a) miRNAs identified CRC in our \"test\" set with 100% sensitivity and 80% specificity. MiR-31 was more upregulated in stages III and IV compared with stages I and II (P < 0.05). In the \"plasma\" group, miR-21 differentiated CRC patients from controls with 90% specificity and sensitivity. CONCLUSIONS: Plasma miRNAs provide reliable and noninvasive markers for CRC. Plasma miR-21 warrants study in larger cohorts. It seems uniquely promising as a plasma biomarker for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22844381,"Year":2012,"Title":"Expression of miR-21, miR-31, miR-96 and miR-135b is correlated with the clinical parameters of colorectal cancer.","Abstract":"The aim of this study was to determine the expression of miR-21, miR-31, miR-96 and miR-135b in 52 paired colorectal cancer (CRC) tissues and to analyze the correlation between microRNAs (miRNAs) and clinicopathological features. We developed a quantification method that relies on a standard plot, constructed from known concentrations of standards, in order to measure the number of miRNAs. In addition to this, we analyzed the expression levels of miR-21, miR-31, miR-96 and miR-135b in 52 cases of primary CRC and corresponding normal mucosal tissue using real-time PCR with SYBR-Green I. An independent sample t-test was used to compare the differential expression between tumor tissues and normal mucosal tissues. The Mann-Whitney U and Kruskall-Wallis tests were used to compare the correlation between miRNA expression levels and clinicopathological features. The expression of miR-21, miR-31, miR-96 and miR-135b was upregulated in the CRC tissues compared to normal mucosal tissues (P<0.05). Furthermore, miR-21 and miR-135b were positively correlated with the clinical stage (P=0.048 and P=0.029, respectively), while miR-96 and miR-135b were correlated with liver metastasis (P=0.006 and P=0.013, respectively). Our results suggest that miR-21, miR-31, miR-96 and miR-135b may function in the process of CRC development and progression. miR-135b levels in particular may correlate with the degree of malignancy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22811001,"Year":2012,"Title":"Circulating miRNA is a novel marker for head and neck squamous cell carcinoma.","Abstract":"The aim of the study is to investigate the alteration of plasma miRNA in head and neck squamous cell carcinoma (HNSCC). Altered microRNAs (miRNAs) expression has been found in many cancers, including lung cancer, breast cancer, prostate cancer, bladder cancer and colorectal cancer. Many recent studies have demonstrated that aberrant plasma miRNAs were also found in various types of cancers. However the alteration of plasma expression in HNSCC remains unclear. In this present study, the expression profiles of ten miRNAs, let-7a, miR-21, miR26b, miR-34c, miR-99a, miR-133a, miR-137, miR-184, miR-194a, and miR-375, in plasma from 50 patients and 36 healthy subjects were evaluated using real-time quantitative polymerase chain reaction (PCR). Our results demonstrated that the expression level of miR-21 was significantly up-regulated in plasma samples obtained from HNSCC patients (p < 0.01) than those from healthy subjects, which were in consistent with our finding in HNSCC tissues. A 7.7-fold increase of miR-21 in cancerous parts when compared to their non-cancerous counterparts (p < 0.0001) was observed in HNSCC tissues. In addition, the expression levels of miR-21 and miR-26b were both reduced in post-operative HNSCC patients with good prognosis. In contrast, the concentration of plasma miR-21 and miR-26b stayed high after tumor removal in the expired cases. Our study suggests that detecting circulating miR-21 and miR-26b pre- and post-operatively might provide a novel tumor marker for HNSCC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22703586,"Year":2012,"Title":"Identifying microRNA-mRNA regulatory network in colorectal cancer by a combination of expression profile and bioinformatics analysis.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are involved in carcinogenesis and tumor progression by regulating post-transcriptional gene expression. However, the miRNA-mRNA regulatory network is far from being fully understood. The objective of this study is to identify the colorectal cancer (CRC) specific miRNAs and their target mRNAs using a multi-step approach. RESULTS: A multi-step approach combining microarray miRNA and mRNA expression profile and bioinformatics analysis was adopted to identify the CRC specific miRNA-mRNA regulatory network. First, 32 differentially expressed miRNAs and 2916 mRNAs from CRC samples and their corresponding normal epithelial tissues were identified by miRNA and mRNA microarray, respectively. Secondly, 22 dysregulated miRNAs and their 58 target mRNAs (72 miRNA-mRNA pairs) were identified by a combination of Pearson's correlation analysis and prediction by databases TargetScan and miRanda. Bioinformatics analysis revealed that these miRNA-mRNAs pairs were involved in Wnt signaling pathway. Additionally, 6 up-regulated miRNAs (mir-21, mir-223, mir-224, mir-29a, mir-29b, and mir-27a) and 4 down-regulated predicted target mRNAs (SFRP1, SFRP2, RNF138, and KLF4) were selected to validate the expression level and their anti-correlationship in an extended cohort of CRC patients by qRT-PCR. Except for mir-27a, the differential expression and their anti-correlationship were proven. Finally, a transfection assay was performed to validate a regulatory relationship between mir-29a and KLF4 at both RNA and protein levels. CONCLUSIONS: Seventy-two miRNA-mRNA pairs combined by 22 dysregulated miRNAs and their 58 target mRNAs identified by the multi-step approach appear to be involved in CRC tumorigenesis. The results in our study were worthwhile to further investigation via a functional study to fully understand the underlying regulatory mechanisms of miRNA in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22677902,"Year":2012,"Title":"miR-21, miR-17 and miR-19a induced by phosphatase of regenerating liver-3 promote the proliferation and metastasis of colon cancer.","Abstract":"BACKGROUND: Phosphatase of regenerating liver-3 (PRL-3) is an oncogene known to promote tumour metastasis, especially in colorectal cancer (CRC). Here, we demonstrate that the miR-21, miR-17 and miR-19a expressions induced by PRL-3 are involved in the proliferation and metastasis of colon cancer. METHODS: Microarray analysis and quantitative reverse-transcription polymerase chain reactions (qRT-PCR) were used to investigate the changes in miRNA expression due to the overexpression of PRL-3. Transwell chamber invasion assays, CCK-8 proliferation assays and RNA interference assays were used to explore the effects of PRL-3 on miR-21, miR-17 and miR-19a expression in colon cancer cells. Immunohistochemistry and qRT-PCR were performed in colon cancer tissues to evaluate the expression of PRL-3, signal transducer and activator of transcription 3 (STAT3), miR-21, miR-17 and miR-19a. RESULTS: Our study demonstrated that the overexpression of PRL-3 in colon cancer cells induced the expression of miR-21, miR-17 and miR-19a by activating STAT3. Subsequently, these microRNAs contributed to the increased proliferation and invasiveness of the colon cancer cells. Positive correlations between PRL-3 and these microRNAs were also observed in matched primary colon cancer tissues and metastatic lesions. CONCLUSION: miR-21, miR-17 and miR-19a induced by PRL-3 contribute to the proliferation and invasion of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22648208,"Year":2012,"Title":"Circulating miR-34a levels are reduced in colorectal cancer.","Abstract":"INTRODUCTION: MicroRNAs (miRNAs) are small, non-coding RNA segments that regulate gene expression via post-transcriptional inhibition and have roles in cell differentiation, proliferation, and apoptosis. Expression differs between tumor and normal tissue in several malignancies. Most work has focused on tissue and cell expression with few reports of circulating miRNAs in colorectal cancer. Available biomarkers for colorectal cancer have limited sensitivity and specificity, thus there is a need for new markers. AIMS: This study aimed to identify miRNAs that are differentially expressed in the blood of colorectal cancer patients compared to controls and to establish if this is specific to colorectal cancer and thus could be utilized as potential tumor markers. METHODS: Blood samples were collected from 63 colorectal cancer patients and 45 controls. Expression of 7 target miRNAs (miR-143, miR-145, miR-21, miR-30a-3p, miR-31, miR-34a, and miR-92) was measured using RQ-PCR. Results were correlated with clinicopathological data and analyzed. Analysis of differentially expressed circulating miRNAs was expanded to include 62 patients with prostate, renal, breast, and melanoma cancers. RESULTS: Analysis of the relative quantification of the target miRNAs showed significantly reduced expression (P = 0.004) of miR-34a in colorectal cancer. MiR-34a was also significantly reduced in breast cancer (P = 0.019). CONCLUSION: This study demonstrates significantly reduced expression of circulating miR-34a in colorectal and breast cancer. This may have future application as part of a biomarker profile.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22638884,"Year":2012,"Title":"The expression and clinical significance of circulating microRNA-21 in serum of five solid tumors.","Abstract":"PURPOSE: MicroRNA-21 (miR-21) was reported as being overexpressed in various human cancerous tissues, but its expression in cancerous serum was not unanimous in different laboratories. On the base of optimizing experimental design and improving trial protocol, we wanted to know whether the circulating microRNA-21 was dysregulated in the common solid cancers. METHODS: Using SYBR green real-time quantitative reverse transcription-PCR, we detected the expression of circulating miR-21 in 174 patients with solid cancers and 39 normal control subjects, including breast cancer, esophageal cancer, gastric cancer, colorectal cancer, lung cancer. Furthermore, we analyzed the associations between miR-21 expression and clinical features of patients. RESULTS: miR-21 was significantly overexpressed in human solid cancerous serum relative to normal control (P < 0.001), and its sensitivity and specificity were significantly higher than the currently used tumor markers. High miR-21 expression was not correlated with gender, age, clinical stage, and lymph node metastasis status. CONCLUSION: Circulating miR-21 could serve as a potential broad-spectrum serum-based biomarker for the detection of some solid cancers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22553926,"Year":2012,"Title":"Control of MicroRNA-21 expression in colorectal cancer cells by oncogenic epidermal growth factor/Ras signaling and Ets transcription factors.","Abstract":"MicroRNAs (miRs) are important regulators of gene expression in normal physiology and disease, and are widely misexpressed in cancer. A number of studies have identified miR-21 as an important promoter of oncogenesis. However, as is true of most miRs, the mechanisms behind the aberrant expression of miR-21 in cancer are poorly understood. Herein, we examine the regulation of miR-21 expression in colorectal cancer (CRC) cells by the oncogenic epidermal growth factor (EGF)/Ras pathway and by Ets transcription factors, modulators of epithelial oncogenesis that are frequently misexpressed in CRC. We show that EGF/Ras efficiently induces the miR-21 primary transcript, but this does not rapidly and simply translate into higher mature miR-21 levels. Rather, induction of mature miR-21 by constitutive activation of this pathway is slow, is associated with only minimal activation of mitogen-activated protein kinase, and may involve stimulation of post-transcriptional processing by mechanisms other than Dicer stabilization. We further identify Ets transcription factors as modifiers of miR-21 expression in CRC. The effects of Ets factors on miR-21 expression are cell context-dependent, and appear to involve both direct and indirect mechanisms. The Ets factor Pea3 emerges from our studies as a consistent repressor of miR-21 transcription. Overall, our studies identify a complex relationship between oncogenic pathways and steady-state miR-21 levels in CRC, and highlight the need for greater understanding of the control of miR expression in cancer and other disease states.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22480843,"Year":2012,"Title":"Utility of micro-ribonucleic acid profile for predicting recurrence of rectal cancer.","Abstract":"BACKGROUND: In early-stage rectal cancer, the surgeon must decide between the high morbidity of radical surgery and the high recurrence rates of local excision. A prognostic marker could improve patient selection and lower recurrence rates. Micro-ribonucleic acids (miRNAs), small RNAs that often inhibit tumor suppressors, have shown prognostic potential in colorectal cancer. We hypothesized that high miRNA levels in malignant tissue from early-stage rectal cancer patients could predict recurrence after local excision. MATERIALS AND METHODS: We identified 17 early-stage rectal cancer patients treated with local excision between 1990 and 2005, four of whom had recurrences. Total RNA was extracted from benign and malignant tissue and used in quantitative real-time reverse transcriptase polymerase chain reaction to probe for miR-20a, miR-21, miR-106a, miR-181b, and miR-203. MiRNA data were evaluated for association with recurrence using univariate analysis with Wilcoxon rank sum test. RESULTS: Malignant tissue in both patients who had recurrences and patients who did not have recurrences had equivalently high levels of miRNA. However, the benign tissue of patients who recurred contained significantly higher levels of all five miRNAs when compared with the benign tissue of nonrecurrent patients despite having no histological differences. CONCLUSIONS: This is the first study to show that high miRNA levels of histologically benign tissue obtained from the surgical margin of locally excised rectal cancers can predict recurrence. The malignant miRNA levels did not have predictive value. Further investigation of miRNAs is needed to explore their potential for a more accurate prognosis of rectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22476768,"Year":2012,"Title":"Clinical correlations of miR-21 expression in colorectal cancer patients and effects of its inhibition on DLD1 colon cancer cells.","Abstract":"PURPOSE: MicroRNA-21 (miR-21) is one of the miRNAs that are frequently and highly overexpressed in tumor tissue of colorectal cancer (CRC) patients; however, only a little is known about its functional role in CRC. METHODS: We examined the expression level of miR-21 in 44 paired samples of tumoral and non-tumoral colon tissues diagnosed for CRC using TaqMan real-time PCR method. Furthermore, we used miR-21 inhibitor (anti-miR-21) to transient knockdown of miR-21 in DLD-1 colon cancer cells and examined the effects of miR-21 silencing on viability, apoptosis, chemosensitivity, cell cycle, and migration of DLD1 cells. RESULTS: The expression levels of miR-21 were significantly increased in CRC tumor tissue (P < 0.0001). Significant differences in miR-21 levels were observed also between CRC tissues of patients with CRC in different clinical stages: I vs. II (P = 0.033) and I vs. IV (P = 0.021). Kaplan-Meier analysis proved that the miR-21 expression levels are correlated to shorter overall survival of CRC patients (P = 0.0341). MiR-21 silencing in DLD1 cell line had no effect on the cell viability; however, when combined with chemotherapeutics (5-FU, L-OHP, and SN38), it contributed to the decrease of cell viability. Suppression of miR-21 decreased cell migration ability of DLD-1 cells by nearly 30 % (P = 0.016). CONCLUSION: We have confirmed the overexpression of miR-21 in CRC samples and its correlation with advanced disease and shorter overall survival. These findings could be described in part by the fact that CRC cells with increased expression of miR-21 have higher migration ability.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22382630,"Year":2012,"Title":"Role of miR-19b and its target mRNAs in 5-fluorouracil resistance in colon cancer cells.","Abstract":"BACKGROUND: Drug resistance in colorectal cancers is assumed to be mediated by changes in the expression of microRNAs, but the specific identities and roles of microRNAs are largely unclear. We examined the effect of 5-fluorouracil (5-FU) resistance on microRNA expression. METHODS: Two types of 5-FU-resistant colon cancer cells were derived from the DLD-1 and KM12C cell lines. The expressions of microRNAs were profiled with a microarray containing 723 microRNAs and validated by quantitative real-time polymerase chain reaction (qRT-PCR). To survey the downstream mediators of microRNA, we used a microRNA:mRNA immunoprecipitation (RIP)-Chip and pathway analysis tool to identify potential direct targets of microRNA. RESULTS: In response to 5-FU, miR-19b and miR-21 were over-expressed in 5-FU-resistant cells. Of note, miR-19b was up-regulated 3.47-fold in the DLD-1 resistant cells, which exhibited no alteration in cell cycle profiles despite exposure to 5-FU. After transfection of miR-19b, specific mRNAs were recruited to microRNA:mRNA complexes isolated with Ago2 antibody and subjected to whole-genome transcriptional analysis. In this analysis, 66 target mRNAs were enriched by at least 5.0-fold in the microRNA:mRNA complexes from DLD-1 resistant cells. Ingenuity pathway analysis of mRNA targets significantly (P < 0.05) indicated the category \"Cell Cycle\" as a probable area of the molecular and cellular function related with 5-FU resistance. Among candidate mRNA targets, SFPQ and MYBL2 have been linked to cell cycle functions. CONCLUSIONS: We revealed up-regulation of miR-19b in response to 5-FU and potential targets of miR-19b mediating the cell cycle under treatment with 5-FU. Our study provides an important insight into the mechanism of 5-FU resistance in colorectal cancers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22347428,"Year":2012,"Title":"Up-regulation of microRNA-21 correlates with lower kidney cancer survival.","Abstract":"BACKGROUND: MicroRNA-21 is up-regulated in a variety of cancers like, breast, colorectal, lung, head and neck etc. However, the regulation of miR-21 in renal cell carcinoma (RCC) has not yet been studied systematically. METHODS AND RESULTS: We measured miR-21 levels in 54 pairs of kidney cancers and their normal matched tissues by real-time PCR. The expression level of miR-21 was correlated with 5 year survival and the pathological stage. Functional studies were done after inhibiting miR-21 in RCC cell lines. We studied in vitro and in vivo effects of the chemo preventive agent genistein on miR-21 expression. In 48 cases (90%), miR-21 was increased. All patients with low miR-21 expression survived 5 years, while with high miR-21 expression, only 50% survived. Higher expression of miR-21 is associated with an increase in the stage of renal cancer. Functional studies after inhibiting miRNA-21 in RCC cell lines show cell cycle arrest, induction of apoptosis and reduced invasive and migratory capabilities. Western blot analysis showed an increase in the expression of p21 and p38 MAP kinase genes and a reduction in cyclin E2. Genistein inhibited the expression of miR-21 in A-498 cells and in the tumors formed after injecting genistein treated A-498 cells in nude mice besides inhibiting tumor formation. CONCLUSIONS: The current study shows a clear correlation between miR-21 expression and clinical characteristics of renal cancer. Thus we believe that miR-21 can be used as a tumor marker and its inhibition may prove to be useful in controlling cancers with up-regulated miR-21.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22343615,"Year":2012,"Title":"miRNA profiling in colorectal cancer highlights miR-1 involvement in MET-dependent proliferation.","Abstract":"Altered expression of miRNAs is associated with development and progression of various human cancers by regulating the translation of oncogenes and tumor suppressor genes. In colorectal cancer, these regulators complement the Vogelstein multistep model of pathogenesis and have the potential of becoming a novel class of tumor biomarkers and therapeutic targets. Using quantitative real-time PCR, we measured the expression of 621 mature miRNAs in 40 colorectal cancers and their paired normal tissues and identified 23 significantly deregulated miRNAs. We subsequently evaluated their association with clinical characteristics of the samples and presence of alterations in the molecular markers of colorectal cancer progression. Expression levels of miR-31 were correlated with CA19-9 and miR-18a, miR-21, and miR-31 were associated with mutations in APC gene. To investigate the downstream regulation of the differentially expressed miRNAs identified, we integrated putative mRNA target predictions with the results of a meta-analysis of seven public gene expression datasets of normal and tumor samples of colorectal cancer patients. Many of the colorectal cancer deregulated miRNAs computationally mapped to targets involved in pathways related to progression. Here one promising candidate pair (miR-1 and MET) was studied and functionally validated. We show that miR-1 can have a tumor suppressor function in colorectal cancer by directly downregulating MET oncogene both at RNA and protein level and that reexpression of miR-1 leads to MET-driven reduction of cell proliferation and motility, identifying the miR-1 downmodulation as one of the events that could enhance colorectal cancer progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22322462,"Year":2012,"Title":"MicroRNA-21-mediated regulation of Sprouty2 protein expression enhances the cytotoxic effect of 5-fluorouracil and metformin in colon cancer cells.","Abstract":"Sprouty2 (Spry2) was identified recently as a tumor suppressor gene in cancer cells which inhibits the activation of receptor tyrosine kinases (RTKs). The present study explored the effect of Spry2 in colon cancer cells in order to assess its potential use in the treatment of colon cancer. Expression of Spry2 inhibited the growth of a colon cancer cell line, HCT116, and induced sensitization to fluorouracil (5-FU) and metformin. Spry2 promoted apoptosis of cancer cells in association with activation of the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) pathway and the blockade of Ras-Raf-Erk signaling. Treatment of Spry2-HCT116 cells with metformin resulted in a more prominent effect on the inhibition of cell migration. Inhibition of microRNA-21 (mir21) induced upregulation of Spry2 and PTEN which underscores the importance of mir-21 in Spry2-associated tumorigenesis of the colon. These results point toward a potential strategy for colon cancer treatment worthy of further investigation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22289545,"Year":2011,"Title":"Increased expression of microRNA-21and its association with chemotherapeutic response in human colorectal cancer.","Abstract":"The expression of microRNA-21 (miR-21) was determined in 42 patients with colorectal cancer (CRC) using real-time reverse transcription-polymerase chain reaction. The level of miR-21 in CRC tumour tissue was compared with paired normal adjacent tissue (NAT) and the relationships of miR-21 levels to clinicopathological characteristics and pathological tumour response to neoadjuvant chemotherapy were investigated. There was a significantly higher level of miR-21 in CRC tumour tissue than in NAT and high expression of miR-21 was significantly correlated with advanced clinical stage and poor cell differentiation. Receiver operating characteristic curve analysis indicated a maximum optimal cut-off cycle threshold value of 10.32 for differentiating pathological responders from non-responders, with a sensitivity of 80.0% and specificity of 88.2%. These data showed that miR-21 was significantly overexpressed in CRC tumour tissue and was associated with advanced CRC, and that miR-21 may be a potential candidate biomarker for predicting pathological tumour response to chemotherapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22281474,"Year":2012,"Title":"EGFR regulation of colon cancer stem-like cells during aging and in response to the colonic carcinogen dimethylhydrazine.","Abstract":"One of the most consistent pathological conditions in the gastrointestinal tract with advancing age is malignancy, particularly gastrointestinal cancers, the incidence of which increases sharply with aging. Although the reasons for the age-related rise in colorectal cancer are not fully understood, we hypothesize that aging increases susceptibility of the colon to carcinogen(s)/toxicant(s), leading to an increase in cancer stem-like cells (CSLCs) that express cancer stem cell markers, in the colonic mucosa. The current study demonstrates that aging is associated with increased expression of several colon CSLC markers [CD44, CD166, and aldehyde dehydrogenase 1 (ALDH-1)] and a higher proportion of cells expressing these markers. Aging is also accompanied by increased expression of miR-21 in colon. These increases are further increased in response to the colonic carcinogen dimethylhydrazine (DMH). Aging is also associated with increased tyrosine-phosphorylated epidermal growth factor receptor (EGFR). Inhibition of EGFR using the EGFR inhibitor cetuximab abrogated the age-related increase in CD166 and ALDH-1 as well as miRNA (miR)-21. Our results provide new evidence that aging and DMH are associated with increases in CSLC biomarkers and miR21, each of which have been linked to colorectal cancer. EGFR inhibition attenuates these changes, indicating a role for EGFR in age- and mutagen-associated changes in CSLCs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22273643,"Year":2012,"Title":"Down-regulation of fecal miR-143 and miR-145 as potential markers for colorectal cancer.","Abstract":"OBJECTIVE: To detect 4 MicroRNA (miRNA) in the stool samples of colorectal cancer (CRC) patients to determine whether these miRNAs could be biomarkers in CRC screening or treatment. METHODS: A retrospective comparison study was carried out in the Department of Colorectal Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China from September 2009 to March 2011. We detected 4 miRNAs (miR-143, miR-145, miR-21, and miR-106a) in the stool samples of 38 CRC patients and 13 healthy individuals. Total RNA from the stool samples was extracted using the EZNA TM stool RNA kit R6828-01. The miRNA quantification was carried out using TaqMan miRNA assays and the TaqMan Gene Expression Master Mix. RESULTS: The expression levels of miR-143 and miR-145 in the stool of the CRC patients were lower than in those of the healthy persons (p<0.005, median of 2-ct). No statistically significant difference was found in the expression levels of both miR-21 and miR-106a between the stool of CRC patients and those of the healthy persons (p>0.05). CONCLUSION: The detection of fecal miRNAs is a potential method for CRC diagnosis or screening. Particularly, the down-regulation of fecal miR-143 and miR-145 could be a potential marker for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22267128,"Year":2012,"Title":"Prognostic significance of PDCD4 expression and association with microRNA-21 in each Dukes' stage of colorectal cancer patients.","Abstract":"Down-regulation of the novel tumor suppressor gene programmed cell death 4 (PDCD4) was demonstrated in several types of cancer and regulation by micro-RNA is gaining attention. However, the clinical significance of the PDCD4 gene in colorectal cancer (CRC) patients still remains unclear. In particular, the significance of PDCD4 mRNA expression in each tumor stage has not been reported. In this study, we evaluated the prognostic value of PDCD4 expression in each Dukes' stage of CRC patients. Furthermore, relationships between the PDCD4 mRNA and microRNA-21 (miR-21) were evaluated. Tumor tissues and normal adjacent tumor tissues from 326 patients with CRC (Dukes' stage A, 44 cases; Dukes' B, 118 cases; Dukes' C, 100 cases; Dukes' D, 64 cases) were examined. The PDCD4 mRNA was investigated by the quantitative real-time RT-PCR method and miR-21 was examined by TaqMan microRNA assays. The overall survival rates (OS) and disease-free survival rates (DFS) of low PDCD4 patients were significantly worse than those of patients with high expression. In analysis of each tumor stage, OS and DFS of patients with low PDCD4 levels were significantly worse than those with high PDCD4 levels in Dukes' stage B and C. In Dukes' stage D, patients with low PDCD4 expression showed a significant worse OS compared to those of patients with high PDCD4 expression. In contrast, no significant differences were seen between these groups in patients with Dukes' stage A. PDCD4 expression in CRC tissues was an independent prognostic factor in Dukes' stage B, C and D. Significant inverse correlations were demonstrated between PDCD4 and miR-21. The reduced PDCD4 mRNA expression is associated with poor prognosis in CRC patients with Dukes' stage B, C and D. Furthermore, PDCD4 mRNA levels were negatively regulated by miR-21in each tumor stage of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22202009,"Year":2012,"Title":"miRNAs are stable in colorectal cancer archival tissue blocks.","Abstract":"MicroRNAs (miRNAs) have prognostic and therapeutic value for colorectal cancers RCs). Although formalin-fixed paraffin-embedded (FFPE) tissues are available for biomarker studies, the stability of miRNAs in these tissues stored for long periods (more than 20 years) is unknown. The present effort involved analysis of 345 FFPE CRC tissues, stored for 6 to 28 years (1982-2004), for the expression of six miRNAs (miR-20a, miR-21, miR-106a, miR-181b, miR-203, and miR-324-5p) using TaqMan(r) microRNA assays and quantitative real-time PCR (qRT-PCR). Evaluation, by linear regression analysis, of miRNA expression among archived CRC tissues found similar levels of all six miRNAs in tissues stored over this period (correlation coefficients, R2, ranged from less than 0.0001-0.009; and t-test p-values were greater than or equal to 0.05). Thus, miRNAs are stable in FFPE tissues stored for long periods of time, and such samples can be used for discovery of biomarkers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22120473,"Year":2012,"Title":"Stage-dependent differential expression of microRNAs in colorectal cancer: potential role as markers of metastatic disease.","Abstract":"MicroRNAs (miRs) are short non-coding RNAs that bind complementary sequences in mRNA resulting in translation repression and/or mRNA degradation. We investigated expression of the reported metastasis-associated miRs-335, 206, 135a, 146a, 146b, 10b, 21, let7a and let7b in normal mucosa, non-metastatic and metastatic colorectal cancer (CRC). Expression of target miRs in micro-dissected paraffin embedded tissues was evaluated in 15 primary tumours with adjacent normal tissue from patients that were disease-free at 4 years (cohort A) and 19 paired primary tumours with corresponding liver metastases (cohort B) by quantitative real-time PCR. Increased expression of miR-21, mir-135a and miR-335 was associated with clinical progression of CRC, while miR-206 demonstrated an opposite trend. The levels of mir-21 did not associate with the expression of PTEN, an important tumour suppressor in CRC and one of many putative targets of miR-21, but interestingly was associated with stage of disease in the PTEN expressing tumours. Surprisingly, let7a, a KRAS-targeting miR, showed elevated expression in metastatic disease compared to normal mucosa or non-metastatic disease, and only in KRAS mutation positive tumors. Finally, a prognostic signature of miR 21,135a, 335, 206 and let-7a for detecting the presence of metastases had a specificity of 87% and sensitivity of 76% for the presence of metastases. In summary, we have shown stage-associated differential expression of five out of nine tested metastasis-associated miRs. We have further found that an analysis of these five miRs expression levels in primary tumors significantly correlates with the presence of metastatic disease, making this a potential clinically useful prognostic tool.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22099878,"Year":2012,"Title":"miR-21 functionally interacts with the 3'UTR of chemokine CCL20 and down-regulates CCL20 expression in miR-21 transfected colorectal cancer cells.","Abstract":"As deregulation of miRNAs and chemokine CCL20 was shown to play a role in colorectal cancer (CRC) pathogenesis, we analyzed the functional interactions of candidate miRNAs with CCL20 mRNA. After target prediction software programs indicated a role for miR-21 in CCL20 regulation, we applied the luciferase reporter assay system to demonstrate that miR-21 functionally interacts with the 3'UTR of CCL20 mRNA and down-regulates CCL20 in miR-21 mimic transfected CRC cell lines (Caco-2, SW480 and SW620). Thus, regulation of CCL20 expression by miR-21 might be a regulatory mechanism involved in progression of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":22072622,"Year":2012,"Title":"MicroRNA-21 induces stemness by downregulating transforming growth factor beta receptor 2 (TGFbetaR2) in colon cancer cells.","Abstract":"Although microRNA-21 (miR-21) is emerging as an oncogene and has been shown to target several tumor suppressor genes, including programmed cell death 4 (PDCD4), its precise mechanism of action on cancer stem cells (CSCs) is unclear. Herein, we report that FOLFOX-resistant HCT-116 and HT-29 cells that are enriched in CSCs show a 3- to 7-fold upregulation of pre- and mature miR-21 and downregulation of PDCD4. Likewise, overexpression of miR-21 in HCT-116 cells, achieved through stable transfection, led to the downregulation of PDCD4 and transforming growth factor beta receptor 2 (TGFbetaR2). In contrast, the levels of beta-catenin, TCF/LEF activity and the expression of c-Myc, Cyclin-D, which are increased in CSCs, are also augmented in miR-21 overexpressing colon cancer cells, accompanied by an increased sphere forming ability in vitro and tumor formation in SCID mice. Downregulation of TGFbetaR2 could be attributed to decreased expression of the receptor as evidenced by reduction in the activity of the luciferase gene construct comprising TGFbetaR2-3' untranslated region (UTR) sequence that binds to miR-21. Moreover, we observed that downregulation of miR-21 enhances luciferase-TGFbetaR2-3' UTR activity suggesting TGFbetaR2 as being one of the direct targets of miR-21. Further support is provided by the observation that transfection of TGFbetaR2 in HCT-116 cells attenuates TCF/LEF luciferase activity, accompanied by decreased expression of beta-catenin, c-Myc and Cyclin-D1. Our current data suggest that miR-21 plays an important role in regulating stemness by modulating TGFbetaR2 signaling in colon cancer cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21956205,"Year":2012,"Title":"Genome-wide identification of TCF7L2/TCF4 target miRNAs reveals a role for miR-21 in Wnt-driven epithelial cancer.","Abstract":"Transcription factor 7 like 2 (TCF7L2, also known as TCF4) is a Wnt signaling pathway transcription factor involved in regulation of numerous Wnt targeted genes. Recently, thousands of high-confidence TCF4 binding sites were reported in LS174T colon carcinoma cells, however, potential TCF4 target miRNAs remain largely unknown. Here, we utilized a bioinformatics approach to discover 26 miRNA transcription start sites (TSSs) within close proximity to TCF4 chromatin occupancy sites, and validated these sites as bona fide TCF4 targets in LS174T colon carcinoma cells, MCF-7 breast cancer cells and U87 glioma cells by ChIP-PCR. We then selected miR-21 to demonstrate for the first time direct TCF4 transcriptional activation of a miRNA via binding to the promoter region. Tissue array analysis supported this finding, revealing a positive correlation between activation of the beta-catenin pathway and in situ expression of miR-21. Finally, based upon the well known but poorly understood preventive effect of aspirin on colorectal cancer incidence and mortality, we report downregulation of miR-21 upon administration of aspirin. In sum, our findings identify direct transcriptional regulation of miR-21 by TCF4 and suggest a role for miR-21 in cancer cell proliferation and invasion upon activation of beta-catenin/TCF4 signaling.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21930727,"Year":2012,"Title":"Detection of miR-92a and miR-21 in stool samples as potential screening biomarkers for colorectal cancer and polyps.","Abstract":"OBJECTIVE: The detection of molecular markers in stool samples is a potential strategy for colorectal cancer (CRC) screening. This study evaluated the feasibility of detecting miR-21 and miR-92a in stool samples of patients with CRC or polyps. METHODS: The reproducibility of detection and stability of stool-based microRNA were evaluated. Stool samples were collected from 88 patients with CRC, 57 patients with colorectal polyps and 101 healthy controls. MiRNA levels in CRC tissues and stool samples were detected by real-time quantitative reverse transcription PCR. Stool miR-21 and miR-92a levels were compared before and after the removal of tumour or advanced adenoma. RESULTS: The study demonstrated that stool-based miRNA were stable with highly reproducible detection. The expression of miR-21 and miR-92a was significantly higher in CRC tissues compared with their adjacent normal tissues (p<0.0001). Patients with CRC had a significantly higher stool miR-21 level (p<0.01) and miR-92a level (p<0.0001) compared with normal controls. Stool miR-92a, but not miR-21, was significantly higher in patients with polyps than in controls (p<0.0001). At a cut-off value of 435 copies/ng of stool RNA, miR-92a had a sensitivity of 71.6% and 56.1% for CRC and polyp, respectively, and a specificity of 73.3%. In addition, the stool miR-92a level demonstrated a higher sensitivity for distal CRC than proximal CRC (p<0.05), and a higher sensitivity for advanced adenoma than minor polyps (p<0.05). Removal of tumour resulted in reduced stool miR-21 and miR-92a levels (p<0.01), and the removal of advanced adenoma resulted in a reduction of the stool miR-92a level (p<0.05). CONCLUSION: Stool miRNA are useful for screening CRC and polyps.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21872591,"Year":2011,"Title":"miR-21 targets the tumor suppressor RhoB and regulates proliferation, invasion and apoptosis in colorectal cancer cells.","Abstract":"It has become increasingly clear that microRNAs play an important role in many human diseases including cancer. Here, we show that expression of miR-21 in HEK293 and several colorectal cancer cells was found inversely correlated with ras homolog gene family, member B (RhoB) expression. miR-21 expression significantly suppressed RhoB 3' UTR luciferase-reporter activity, but the inhibitory effect was lost when the putative target sites were mutated. Exogenous miR-21 over-expression mimicked the effect of RhoB knockdown in promoting proliferation and invasion and inhibiting apoptosis, whereas anti-miR-21 or RhoB expression yielded opposite effects, in colorectal cancer cells. These results suggest that miR-21 is a regulator of RhoB expression and RhoB could be a useful target in exploring the potential therapeutic benefits of miR-21 mediated tumor cell behaviors in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21806946,"Year":2011,"Title":"Neurotensin signaling activates microRNAs-21 and -155 and Akt, promotes tumor growth in mice, and is increased in human colon tumors.","Abstract":"BACKGROUND & AIMS: Neurotensin promotes inflammation and colon cancer via the neurotensin-1 receptor (NTR1). MicroRNAs (miR) regulate protein synthesis by degrading or preventing translation of mRNAs. We analyzed expression of 365 different microRNAs by human colonic epithelial cells (NCM460) after activation of NTR1. METHODS: We performed microarray analysis of mRNA expression by neurotensin-stimulated NCM460 cells that overexpressed NTR1. Nuclear factor-kappaB (NF-kappaB) binding sites were identified and tumorigenesis was assessed using soft agar assays and xenograft analysis of severe combined immunodeficiency mice. Targets of neurotensin-regulated microRNAs were identified via bioinformatic, real-time polymerase chain reaction, and immunoblot analyses. We analyzed RNA samples from human normal colon and tumor samples. RESULTS: Neurotensin stimulated differential expression of 38 microRNAs, including miR-21 and miR-155, which have been associated with tumor growth and contain NF-kappaB binding sites. Neurotensin expression increased colony formation by HCT-116 cells. Blocking miR-21 and/or miR-155 prevented colony formation (P < .001). In mice, intraperitoneal administration of neurotensin increased the growth rate of HCT-116 xenograft tumors; blocking miR-21 and/or miR-155 slowed this tumor growth. Neurotensin activated Akt in HCT-116 cells; this effect was inhibited by blocking miR-21 and/or miR-155 (P < .001). Neurotensin activated AKT through miR-155-mediated suppression of the phosphatase protein phosphatase 2A catalytic subunit alpha (PPP2CA). Levels of phosphatase and tensin homolog (PTEN) and suppressor of cytokine signaling 1 (SOCS1) mRNA, potential targets of miR-21 and miR-155, respectively, were down-regulated by these miRs. Levels of NTR1, miR-21, and miR-155 increased significantly in human colon tumor samples, compared with normal tissues, whereas PPP2CA, SOCS1, and PTEN mRNAs were reduced significantly. CONCLUSIONS: NTR1 activation stimulates expression of miR-21 and miR-155 in colonocytes, via Akt and NF-kappaB, to down-regulate PTEN and SOCS1 and promote growth of tumors in mice. Levels of NTR1, miR-21, and miR-155 increase in human colon tumor samples and correlate with tumor stage.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21743960,"Year":2011,"Title":"Prognostic impact of disseminated tumor cells and microRNA-17-92 cluster deregulation in gastrointestinal cancer.","Abstract":"The presence of tumor cells in the bone marrow (BM) could be relevant to identifying high risk of disease progression and death in gastrointestinal cancer. However, the molecular profile associated with disseminated tumor cells (DTCs) homing to the BM has yet to be defined. MicroRNAs (miRNA) play key roles in cellular processes implicated in cancer. Thus, we investigated in 38 patients with colorectal, gastric or pancreatic cancer whether the presence of BM-DTCs is associated with a specific miRNA tumor profile and analyzed their potential prognostic impact. DTCs were detected by immunocytochemistry and anti-cytokeratin antibodies in 42.1% of the patients. miRNAs were isolated from formalin-fixed, paraffin-embedded tumors. qRT-PCR was used for miRNA profiling. No significant associations were found among DTC detection and miRNA deregulation. Kaplan-Meier curves demonstrated significantly reduced progression-free survival (PFS) and overall survival (OS) in the DTC-positive patients. Although miR-21 was upregulated in 90.6% of the tumors, no associations with outcomes were found. miR-17 and miR-20a (miRNA-17-92 cluster) were upregulated in 33.3 and 42.4%, respectively. Upregulation of both was correlated and found in 30.3%. Univariate analysis shows that increasing values for miR-20a were significantly associated with reduced PFS (HR 1.022; p=0.016) and OS (HR 1.027; p=0.003). In multivariate Cox models, DTC positivity (HR 4.07; p=0.005) and miR-17 overexpression (HR 2.11; p=0.003) were significantly associated with a higher risk of disease progression. The presence of DTCs in the BM (HR 3.98; p=0.010) and a miR-17 overexpression (HR 2.62; p<0.001) were also associated with a risk of death. Our study suggests that the presence of BM-DTCs and the upregulation of the miR-17-92 cluster in tumors are both significant but independent prognostic markers in gastrointestinal cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21567082,"Year":2011,"Title":"Altered levels of the onco-microRNA 21 and the tumor-supressor microRNAs 143 and 145 in advanced rectal cancer indicate successful neoadjuvant chemoradiotherapy.","Abstract":"microRNAs (miRNAs) are small non-coding RNAs with important post-transcriptional regulatory functions. miRNA-21 (miR-21) is upregulated and miR-143 and miR-145 are downregulated in colorectal carcinoma. The aim of our study was to determine if these miRNAs change their expression levels in response to neoadjuvant chemoradiotherapy in advanced rectal cancer. Forty patients with advanced rectal cancer (clinical uT3/T4 Nx) were included. All patients underwent neoadjuvant chemoradiotherapy and surgical resection. Expression of miR-21, -143 and -145 was examined in macrodissected tumor tissue before and after chemoradiotherapy and normal rectal tissue from the resection specimen. RNA was extracted from formalin-fixed and paraffin-embedded tissue by TRIzol method, polyadenylated, reverse transcribed and analyzed by real-time PCR. Therapy response was assessed according to pathological tumor regression. miR-21 was more highly expressed in tumor tissue than in non-tumorous tissue. However, there was a moderately lower expression in post-therapeutic tumor tissue compared to pre-therapeutic tumor tissue. There was a significant upregulation of miR-143 and miR-145 in post-therapeutic tumor tissue compared to pre-therapeutic tumor tissue. According to the predictive and prognostic value of the analyzed miRNAs, a significant correlation between miR-145 expression and tumor regression was seen. Patients with a low intratumoral post-therapeutic expression had significantly more often a worse response to neoadjuvant therapy compared to patients with a high expression of miR145. The present results support the hypothesis that chemoradiotherapy can profoundly alter miRNA expression profiles. miRNAs might play important roles as molecular biomarkers in the prediction of response to treatment and prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21546206,"Year":2011,"Title":"MicroRNA-21 and PDCD4 expression in colorectal cancer.","Abstract":"INTRODUCTION: MiRNAs regulate gene expression by binding to target sites and initiating translational repression and/or mRNA degradation. Studies have shown that miR-21 exerts its oncogenic activity by targeting the PDCD4 tumour suppressor 3'-UTR. However, the mechanism of this regulation is poorly understood. In colorectal cancer, loss of PDCD4 has been reported in association with increased tumour aggressiveness and poor prognosis. The purpose of this study was to delineate the interaction between PDCD4 and its oncogenic modulator miR-21 in colorectal cancer. METHODS: A cohort of 48 colorectal tumours, 61 normal tissues and 7 polyps were profiled for miR-21 and PDCD4 gene expression. A subset of 48 specimens (31 tumours and 17 normal tissues) were analysed for PDCD4 protein expression by immunohistochemistry. RESULTS: A significant inverse relationship between miR-21 and PDCD4 gene expression (p < 0.001) was identified by RT-qPCR. In addition, significant reduction of PDCD4 (p < 0.001) expression and reciprocal upregulation of miR-21 (p = 0.005) in a progressive manner from tumour-polyp-normal mucosae was identified. Analysis of protein expression by IHC revealed loss of PDCD4 staining in tumour tissue. Patients with disease recurrence had higher levels of miR-21. CONCLUSION: This study demonstrates the inverse relationship between miR-21 and PDCD4, thus suggesting that miR-21 post-transcriptionally modulates PDCD4 via mRNA degradation. Pharmacological manipulation of the miR-21/PDCD4 axis could represent a novel therapeutic strategy in the treatment of colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21412018,"Year":2010,"Title":"Clinicopathological and prognostic value of microRNA-21 and microRNA-155 in colorectal cancer.","Abstract":"OBJECTIVE: The clinical significance of microRNA-21 (miR-21) and miR-155 in colorectal cancer (CRC) patients remains elusive. In this study, we established the prognostic value of miR-21 and miR-155 using clinical samples from CRC patients. Furthermore, relationships between these microRNAs and target genes (PDCD4 and TP53INP1 mRNAs) were examined. METHODS: miR-21 and miR-155 expression was assessed in tumor tissue and in adjacent normal tissue of 156 CRC patients by TaqMan MicroRNA assays, and PDCD4 and TP53INP1 mRNA levels were measured by quantitative real-time reverse transcriptase PCR (RT-PCR). RESULTS: High miR-21 expression was significantly associated with venous invasion, liver metastasis and tumor stage, and high miR-155 expression was significantly correlated with lymph node metastases. The overall (OS) and disease-free survival (DFS) rates of patients with high miR-21 expression were significantly worse than those of patients with low miR-21 expression. The OS and DFS of patients with high miR-155 expression were also significantly worse than those in patients with low miR-155 expression. miR-21 and miR-155 expression levels in CRC tissue were independent prognostic factors for OS and DFS. Significant inverse correlations were demonstrated between miR-21 and PDCD4 mRNA, and miR-155 and TP53INP1 mRNA. CONCLUSION: Increases in miR-21 and miR-155 expression may represent effective biomarkers for the prediction of a poor prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21406606,"Year":2011,"Title":"Integrated microRNA and mRNA expression profiling in a rat colon carcinogenesis model: effect of a chemo-protective diet.","Abstract":"We have recently demonstrated that nutritional bioactives (fish oil and pectin) modulate microRNA molecular switches in the colon. Since integrated analysis of microRNA and mRNA expression at an early stage of colon cancer development is lacking, in this study, four computational approaches were utilized to test the hypothesis that microRNAs and their posttranscriptionally regulated mRNA targets, i.e., both total mRNAs and actively translated mRNA transcripts, are differentially modulated by carcinogen and diet treatment. Sprague-Dawley rats were fed diets containing corn oil +/- fish oil with pectin +/- cellulose and injected with azoxymethane or saline (control). Colonic mucosa was assayed at an early time of cancer progression, and global gene set enrichment analysis was used to obtain those microRNAs significantly enriched by the change in expression of their putative target genes. In addition, cumulative distribution function plots and functional network analyses were used to evaluate the impact of diet and carcinogen combination on mRNA levels induced via microRNA alterations. Finally, linear discriminant analysis was used to identify the best single-, two-, and three-microRNA combinations for classifying dietary effects and colon tumor development. We demonstrate that polysomal profiling is tightly related to microRNA changes when compared with total mRNA profiling. In addition, diet and carcinogen exposure modulated a number of microRNAs (miR-16, miR-19b, miR-21, miR26b, miR27b, miR-93, and miR-203) linked to canonical oncogenic signaling pathways. Complementary gene expression analyses showed that oncogenic PTK2B, PDE4B, and TCF4 were suppressed by the chemoprotective diet at both the mRNA and protein levels.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21279518,"Year":2011,"Title":"PDCD4 nuclear loss inversely correlates with miR-21 levels in colon carcinogenesis.","Abstract":"Programmed cell death 4 (PDCD4) has recently been demonstrated to be a new tumor suppressor gene involved in colon carcinogenesis. PDCD4 immunohistochemical expression was assessed in 300 polypoid lesions of the colon mucosa (50 hyperplastic polyps [HP], 50 serrated adenomas [SA], 50 tubular adenomas with low-grade-intraepithelial neoplasia [LG-IEN], 50 tubular adenomas with high-grade-IEN [HG-IEN]), and in 50 colon adenocarcinomas (CRC). As normal controls, we considered 50 biopsy samples obtained from patients with irritable bowel syndrome (N). We further investigated PDCD4 messenger RNA (mRNA) levels by quantitative real-time polymerase chain reaction (PCR) in a different series of N, LG-IEN, HG-IEN, and CRC biopsy samples. miR-21 expression (an important PDCD4-expression regulator) was also determined by quantitative real-time PCR and in situ hybridization. Normal colocytes and HP featured strong PDCD4 nuclear immunostaining whereas a significantly lower PDCD4 nuclear expression was observed in dysplasia (low- and high-grade adenomas and SA) and invasive CRC. PDCD4 immunostaining and mRNA levels decreased significantly as the phenotypic changes occurring during colon carcinogenesis progressively increased (p < 0.001). As expected, miR-21 expression was significantly upregulated in preneoplastic/neoplastic samples, consistent with PDCD4 downregulation. These results consistently support the use of nuclear PDCD4 immunohistochemical downregulation as a novel biomarker for the diagnosis of dysplastic/neoplastic lesions in colon biopsy samples.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21099344,"Year":2011,"Title":"Deregulated expression of sprouty2 and microRNA-21 in human colon cancer: Correlation with the clinical stage of the disease.","Abstract":"Sprouty protein is a novel feedback regulator involved in downstream inactivation of several growth factor receptor pathways. Sprouty2 (Spry2) protein was shown to be downregulated in human cancers. High levels of microRNA-21 (miRNA-21) expression have been associated with poor survival and poor response to adjuvant chemotherapy in cancer patients. But the effect of Spry2 in human colon cancer remained unknown. Paired tumor and normal mucosa samples from patients were examined for their expression of Spry2 mRNA and miRNA-21 by real-time quantitative RT-PCR analysis. Our results show that Spry2 was downregulated in human colon cancer, and its expression levels were lower in advanced-stage tumors than in early-stage tumors. There was a negative correlation between the expression levels of Spry2 and miRNA-21. Furthermore, overexpression of Spry2 suppressed the growth and migration of colon cancer cells with a concomitant increase in PTEN expression and reduction of Akt and MAPK phosphorylation. Spry2 inhibited the growth and tumorigenesis of colon cancer cells in vivo. Conclusively, we show for the first time that Spry2 expression is downregulated and miRNA-21 is upregulated in the clinical samples of colon cancer, which correlates with clinical stage of disease. Thus, Spry2 functions as a tumor suppressor in colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21078976,"Year":2010,"Title":"MicroRNA-21 induces resistance to 5-fluorouracil by down-regulating human DNA MutS homolog 2 (hMSH2).","Abstract":"The overexpression of microRNA-21 (miR-21) is linked to a number of human tumors including colorectal cancer, where it appears to regulate the expression of tumor suppressor genes including p21, phosphatase and tensin homolog, TGFbeta receptor II, and B-cell leukemia/lymphoma 2 -associated X protein. Here we demonstrate that miR-21 targets and down-regulates the core mismatch repair (MMR) recognition protein complex, human mutS homolog 2 (hMSH2) and 6 (hMSH6). Colorectal tumors that express a high level of miR-21 display reduced hMSH2 protein expression. Cells that overproduce miR-21 exhibit significantly reduced 5-fluorouracil (5-FU)-induced G2/M damage arrest and apoptosis that is characteristic of defects in the core MMR component. Moreover, xenograft studies demonstrate that miR-21 overexpression dramatically reduces the therapeutic efficacy of 5-FU. These studies suggest that the down-regulation of the MMR mutator gene associated with miR-21 overexpression may be an important clinical indicator of therapeutic efficacy in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":21069438,"Year":2011,"Title":"High levels of microRNA-21 in the stroma of colorectal cancers predict short disease-free survival in stage II colon cancer patients.","Abstract":"Approximately 25% of all patients with stage II colorectal cancer will experience recurrent disease and subsequently die within 5 years. MicroRNA-21 (miR-21) is upregulated in several cancer types and has been associated with survival in colon cancer. In the present study we developed a robust in situ hybridization assay using high-affinity Locked Nucleic Acid (LNA) probes that specifically detect miR-21 in formalin-fixed paraffin embedded (FFPE) tissue samples. The expression of miR-21 was analyzed by in situ hybridization on 130 stage II colon and 67 stage II rectal cancer specimens. The miR-21 signal was revealed as a blue chromogenic reaction, predominantly observed in fibroblast-like cells located in the stromal compartment of the tumors. The expression levels were measured using image analysis. The miR-21 signal was determined as the total blue area (TB), or the area fraction relative to the nuclear density (TBR) obtained using a red nuclear stain. High TBR (and TB) estimates of miR-21 expression correlated significantly with shorter disease-free survival (p = 0.004, HR = 1.28, 95% CI: 1.06-1.55) in the stage II colon cancer patient group, whereas no significant correlation with disease-free survival was observed in the stage II rectal cancer group. In multivariate analysis both TB and TBR estimates were independent of other clinical parameters (age, gender, total leukocyte count, K-RAS mutational status and MSI). We conclude that miR-21 is primarily a stromal microRNA, which when measured by image analysis identifies a subgroup of stage II colon cancer patients with short disease-free survival.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20959518,"Year":2010,"Title":"MicroRNA expression profiling of exfoliated colonocytes isolated from feces for colorectal cancer screening.","Abstract":"To reduce the colorectal cancer (CRC) mortality rate, we have reported several CRC screening methods using colonocytes isolated from feces. Expression analysis of oncogenic microRNA (miRNA) in peripheral blood was recently reported for CRC detection. In the present study, we conducted miRNA expression analysis of exfoliated colonocytes isolated from feces for CRC screening. Two hundred six CRC patients and 134 healthy volunteers were enrolled in the study. miRNA expression of the miR-17-92 cluster, miR-21, and miR-135 in colonocytes isolated from feces as well as frozen tissues was analyzed by quantitative real-time PCR. The expression of the miR-17-92 cluster, miR-21, and miR-135 was significantly higher in CRC tissues compared with normal tissues. The exfoliated colonocytes of 197 CRC patients and 119 healthy volunteers were analyzed because of the presence of sufficient miRNA concentration. miR-21 expression did not differ significantly between CRC patients and healthy volunteers (P = 0.6). The expression of miR-17-92 cluster and miR-135 was significantly higher in CRC patients than in healthy volunteers (P < 0.0001). The overall sensitivity and specificity by using miRNA expression was 74.1% (146/197; 95% confidence interval, 67.4-80.1) and 79.0% (94/119; 95% confidence interval, 70.6-85.9), respectively. Sensitivity was dependent only on tumor location (P = 0.0001). miRNA was relatively well conserved in exfoliated colonocytes from feces both of CRC patients and healthy volunteers. miRNA expression analysis of the isolated colonocytes may be a useful method for CRC screening. Furthermore, oncogenic miRNA highly expressed in CRC should be investigated for CRC screening tests in the future.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20880178,"Year":2010,"Title":"Circulating miR-221 directly amplified from plasma is a potential diagnostic and prognostic marker of colorectal cancer and is correlated with p53 expression.","Abstract":"BACKGROUND AND AIM: Circulating miRNAs exist in serum and plasma and they can be used as a potential noninvasive molecular marker for colorectal cancer (CRC) diagnosis. The present study was to test the availability of direct amplification of miRNAs from plasma without RNA extraction, and to evaluate its clinical application value in CRC. METHODS: Plasma miR-21, miR-221 and miR-222 levels were determined in 103 CRC patients and 37 healthy normal controls by quantitative reverse transcription-polymerase chain reaction. Immunohistochemical staining for p53, carcinoembryonic antigen (CEA), estrogen receptor (ER) and progesterone receptor (PR) was carried out in the same CRC patient cohort. The correlation between miR-221 levels and protein levels of p53, CEA, ER and PR, clinicopathological features or overall survival was analyzed. RESULTS: A standard curve shows a good linearity between the log of sample input and C(T) values over three orders of magnitude of plasma miR-21, miR-221 and miR-222. ROC curve analysis reveals that the plasma levels of miR-221 is a potential biomarker for differentiating CRC patients from controls. Kaplan-Meier curve assessment shows that the elevated plasma miR-221 level is a significant prognostic factor for poor overall survival in CRC patients. The immunohistochemistry analysis demonstrates a significant correlation between plasma miR-221 level and p53 expression. CONCLUSIONS: The direct amplification of plasma miR-221 can be used as a potential noninvasive molecular marker for diagnosis and prognosis of CRC and is correlated with p53 expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20826792,"Year":2010,"Title":"miR-21 and miR-31 converge on TIAM1 to regulate migration and invasion of colon carcinoma cells.","Abstract":"TGF-beta promotes cell migration and invasion, an attribute that is linked to the pro-metastasis function of this cytokine in late stage cancers. The LIM 1863 colon carcinoma organoid undergoes epithelial-mesenchymal transition (EMT) in response to TGF-beta. This process is markedly accelerated by TNF-alpha, and we found that the levels of miR-21 and miR-31 were prominently elevated under the synergistic actions of TGF-beta/TNF-alpha. Consistent with this, overexpression of either miR-21 or miR-31 significantly enhanced the effect of TGF-beta alone on LIM 1863 morphological changes. More importantly, transwell assays demonstrated the positive effects of both miR-21 and miR-31 in TGF-beta regulation of LIM 1863 motility and invasiveness. Elevated levels of miR-21 and miR-31 also enhanced motility and invasiveness of other colon carcinoma cell lines. We present compelling evidence that TIAM1, a guanidine exchange factor of the Rac GTPase, is a direct target of both miR-21 and miR-31. Indeed in LIM 1863 cells, suppression of TIAM1 is required for miR-21/miR-31 to enhance cell migration and invasion. Therefore, we have uncovered miR-21 and miR-31 as downstream effectors of TGF-beta in facilitating invasion and metastasis of colon carcinoma cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20815812,"Year":2011,"Title":"Curcumin regulates miR-21 expression and inhibits invasion and metastasis in colorectal cancer.","Abstract":"Curcumin has promising potential in cancer prevention and therapy by interacting with proteins and modifying their expression and activity, which includes transcription factors, inflammatory cytokines and factors of cell survival, proliferation and angiogenesis. miR-21 is overexpressed in many tumours, promoting progression and metastasis. In the present study, we examined the potential of curcumin to regulate miR-21, tumour growth, invasion and in vivo metastasis in colorectal cancer. In Rko and HCT116 cells, we identified two new transcriptional start sites of the miR-21 gene and delineated its promoter region. PMA stimulation induced miR-21 expression via motifs bound with AP-1 (activator protein 1) transcription factors. Curcumin treatment reduced miR-21 promoter activity and expression in a dose-dependent manner by inhibiting AP-1 binding to the promoter, and induced the expression of the tumour suppressor Pdcd4 (programmed cell death protein 4), which is a target of miR-21. Curcumin-treated Rko and HCT116 cells were arrested in the G2/M phase with increasing concentrations. Furthermore, curcumin inhibited tumour growth, invasion and in vivo metastasis in the chicken-embryo-metastasis assay [CAM (chorionallantoic membrane) assay]. Additionally, curcumin significantly inhibited miR-21 expression in primary tumours generated in vivo in the CAM assay by Rko and HCT116 cells (P<0.00006 and P<0.035 respectively). Taken together, this is the first paper to show that curcumin inhibits the transcriptional regulation of miR-21 via AP-1, suppresses cell proliferation, tumour growth, invasion and in vivo metastasis, and stabilizes the expression of the tumour suppressor Pdcd4 in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20797623,"Year":2010,"Title":"STAT3 activation of miR-21 and miR-181b-1 via PTEN and CYLD are part of the epigenetic switch linking inflammation to cancer.","Abstract":"A transient inflammatory signal can initiate an epigenetic switch from nontransformed to cancer cells via a positive feedback loop involving NF-kappaB, Lin28, let-7, and IL-6. We identify differentially regulated microRNAs important for this switch and putative transcription factor binding sites in their promoters. STAT3, a transcription factor activated by IL-6, directly activates miR-21 and miR-181b-1. Remarkably, transient expression of either microRNA induces the epigenetic switch. MiR-21 and miR-181b-1, respectively, inhibit PTEN and CYLD tumor suppressors, leading to increased NF-kappaB activity required to maintain the transformed state. These STAT3-mediated regulatory circuits are required for the transformed state in diverse cell lines and tumor growth in xenografts, and their transcriptional signatures are observed in colon adenocarcinomas. Thus, STAT3 is not only a downstream target of IL-6 but, with miR-21, miR-181b-1, PTEN, and CYLD, is part of the positive feedback loop that underlies the epigenetic switch that links inflammation to cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20682703,"Year":2010,"Title":"Fluorescence-based codetection with protein markers reveals distinct cellular compartments for altered MicroRNA expression in solid tumors.","Abstract":"PURPOSE: High-throughput profiling experiments have linked altered expression of microRNAs (miRNA) to different types of cancer. Tumor tissues are a heterogeneous mixture of not only cancer cells, but also supportive and reactive tumor microenvironment elements. To clarify the clinical significance of altered miRNA expression in solid tumors, we developed a sensitive fluorescence-based in situ hybridization (ISH) method to visualize miRNA accumulation within individual cells in formalin-fixed, paraffin-embedded tissue specimens. This ISH method was implemented to be compatible with routine clinical immunohistochemical (IHC) assays to enable the detection of miRNAs and protein markers in the same tissue section for colocalization and functional studies. EXPERIMENTAL DESIGN: We used this combined ISH/IHC assay to study a subset of cancer-associated miRNAs, including miRNAs frequently detected at low (miR-34a and miR-126) and high (miR-21 and miR-155) levels, in a panel of breast, colorectal, lung, pancreas, and prostate carcinomas. RESULTS: Despite the distinct histopathologic alterations of each particular cancer type, general trends emerged that pinpointed distinct source cells of altered miRNA expression. Although altered expressions of miR-21 and miR-34a were manifested within cancer cells, those of miR-126 and miR-155 were predominantly confined to endothelial cells and immune cells, respectively. These results suggest a heterogeneous participation of miRNAs in carcinogenesis by intrinsically affecting cancer cell biology or by modulating stromal, vascular, and immune responses. CONCLUSIONS: We described a rapid and sensitive multicolor ISH/IHC assay and showed that it could be broadly applied as an investigational tool to better understand the etiologic relevance of altered miRNA expression in cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20620599,"Year":2010,"Title":"Relevance of miR-21 and miR-143 expression in tissue samples of colorectal carcinoma and its liver metastases.","Abstract":"MicroRNAs, which are endogenously expressed regulatory noncoding RNAs, have an altered expression in colorectal cancer. The aim of our study was to assess the relationship of miR-21 and miR-143 expression to the prognostic/clinicopathological features of colorectal carcinoma (CRC) and colorectal liver metastases (CLM). The estimation was performed in 46 paired (tumor and control) tissue samples of CRC. Further, we studied 30 tissue samples of CLM. MiR-21 and miR-143 expressions were quantified by using the quantitative reverse transcription polymerase chain reaction method. Relation of miR-21 and miR-143 expression to disease-free interval (DFI) (Wilcoxon; P = 0.0026 and P = 0.0191, respectively) was recorded. There was shorter DFI in patients with a higher expression of miR-21 and, surprisingly, also in patients with a higher expression of miR-143, which is a putative tumor suppressor. There was a higher expression of miR-21 and lower expression of miR-143 in CRC tissue in comparison with adjacent normal colon tissue (P < 0.0001; P < 0.0001, respectively). Similarly, we observed a higher expression of miR-21 and a lower expression of miR-143 in CLM in comparison with normal colon tissue (P < 0.0001; P < 0.0001, respectively). Our results support the hypothesis about oncogenic function of miR-21 and show its relation to DFI. The role of miR-143 in carcinogenesis seems to be more complex.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20551304,"Year":2010,"Title":"Fecal MicroRNAs as novel biomarkers for colon cancer screening.","Abstract":"INTRODUCTION: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths, but currently available noninvasive screening programs have achieved only a modest decrease in mortality. MicroRNAs (miRNA) play an important role in a wide array of biological processes and are commonly dysregulated in neoplasia. We aimed to evaluate the feasibility of fecal miRNAs as biomarkers for colorectal neoplasia screening. MATERIALS AND METHODS: Total RNA was extracted from freshly collected stool samples from 8 healthy volunteers and 29 samples collected via fecal occult blood testing from subjects with normal colonoscopies, colon adenomas, and CRCs. miRNA expression analyses were done with TaqMan quantitative reverse transcription-PCR for a subset of miRNAs. Illumina miRNA microarray profiling was done to evaluate the differences in expression patterns between normal colonic mucosa tissues and stool samples from healthy subjects. RESULTS: We efficiently extracted miRNAs from stool specimens using our developed protocol. Data from independent experiments showed high reproducibility for miRNA extraction and expression. miRNA expression patterns were similar in stool specimens among healthy volunteers, and reproducible in stool samples that were collected serially in time from the same individuals. miRNA expression profiles from 29 patients showed higher expression of miR-21 and miR-106a in patients with adenomas and CRCs compared with individuals free of colorectal neoplasia. CONCLUSION: Our data indicate that miRNAs could be extracted from stool easily and reproducibly. The stools of patients with colorectal neoplasms have unique and identifiable patterns of miRNA expression. IMPACT: Fecal miRNAs may be an excellent candidate for the development of a noninvasive screening test for colorectal neoplasms.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20533548,"Year":2011,"Title":"Micro-RNA-21 regulates TGF-beta-induced myofibroblast differentiation by targeting PDCD4 in tumor-stroma interaction.","Abstract":"Transforming growth factor-beta1 (TGF-beta1) induces stromal fibroblast-to-myofibroblast transdifferentiation in the tumor-stroma interactive microenvironment via modulation of multiple phenotypic and functional genes, which plays a critical role in tumor progression. Up to now, the involvement of micro-RNAs (miRNAs) and their roles in TGF-beta1-induced myofibroblast differentiation in tumor-stroma interaction are unclear. Using quantitative real-time RT-PCR, we demonstrated that the expression of micro-RNA-21 (miR-21) was upregulated in activated fibroblasts after treatment with TGF-beta1 or conditioned medium from cancer cells. To determine the potential roles of miR-21 in TGF-beta1-mediated gene regulation during myofibroblast conversion, we showed that miR-21 expression was downregulated by miR-21 inhibitor and upregulated by miR-21 mimic. Interestingly, downregulation of miR-21 with the inhibitor effectively inhibited TGF-beta1-induced myofibroblast differentiation while upregulation of miR-21 with a mimic significantly promoted myofibroblast differentiation. We further demonstrated that MiR-21 directly targeted and downregulated programmed cell death 4 (PDCD4) gene, which in turn acted as a negative regulator of several phenotypic and functional genes of myofibroblasts. Taken together, these results suggested that miR-21 participated in TGF-beta1-induced myofibroblast transdifferentiation in cancer stroma by targeting PDCD4.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20429937,"Year":2010,"Title":"MicroRNA expression profiling to identify and validate reference genes for relative quantification in colorectal cancer.","Abstract":"BACKGROUND: Advances in high-throughput technologies and bioinformatics have transformed gene expression profiling methodologies. The results of microarray experiments are often validated using reverse transcription quantitative PCR (RT-qPCR), which is the most sensitive and reproducible method to quantify gene expression. Appropriate normalisation of RT-qPCR data using stably expressed reference genes is critical to ensure accurate and reliable results. Mi(cro)RNA expression profiles have been shown to be more accurate in disease classification than mRNA expression profiles. However, few reports detailed a robust identification and validation strategy for suitable reference genes for normalisation in miRNA RT-qPCR studies. METHODS: We adopt and report a systematic approach to identify the most stable reference genes for miRNA expression studies by RT-qPCR in colorectal cancer (CRC). High-throughput miRNA profiling was performed on ten pairs of CRC and normal tissues. By using the mean expression value of all expressed miRNAs, we identified the most stable candidate reference genes for subsequent validation. As such the stability of a panel of miRNAs was examined on 35 tumour and 39 normal tissues. The effects of normalisers on the relative quantity of established oncogenic (miR-21 and miR-31) and tumour suppressor (miR-143 and miR-145) target miRNAs were assessed. RESULTS: In the array experiment, miR-26a, miR-345, miR-425 and miR-454 were identified as having expression profiles closest to the global mean. From a panel of six miRNAs (let-7a, miR-16, miR-26a, miR-345, miR-425 and miR-454) and two small nucleolar RNA genes (RNU48 and Z30), miR-16 and miR-345 were identified as the most stably expressed reference genes. The combined use of miR-16 and miR-345 to normalise expression data enabled detection of a significant dysregulation of all four target miRNAs between tumour and normal colorectal tissue. CONCLUSIONS: Our study demonstrates that the top six most stably expressed miRNAs (let-7a, miR-16, miR-26a, miR-345, miR-425 and miR-454) described herein should be validated as suitable reference genes in both high-throughput and lower throughput RT-qPCR colorectal miRNA studies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":20094072,"Year":2010,"Title":"Role of anti-oncomirs miR-143 and -145 in human colorectal tumors.","Abstract":"We examined the expression levels of microRNAs (miRNAs (miRs)) in colorectal tumors (63 cancer specimens and 65 adenoma specimens) and paired non-tumorous tissues. Decreased expression of miR-143 and -145 was frequently observed in the adenomas and cancers tested, compared with miR-34a downregulation and miR-21 upregulation. Expression profiles of miR-143 and -145 were not associated with any clinical features. As the downregulation of miR-143 and -145 was observed even in the early phase of adenoma formation, the decreased expression of both miRs would appear to contribute mainly to the initiation step of tumorigenesis, not to the progression stage, and not to clinical prognostic factors. For clinical application, we changed the sequences of the passenger strand in the miR-143 duplex and performed chemical modification at the 3'-overhang portion of miR-143, leading to greater activity and stability to nuclease. The cell growth inhibitory effect of the chemically modified synthetic miR-143 in vitro was greater than that of endogenous miR-143. The miR-143 showed a significant tumor-suppressive effect on xenografted tumors of DLD-1 human colorectal cancer cells. These findings suggest that miR-143 and -145 are important onco-related genes for the initiation step of colorectal tumor development and that the chemically modified synthetic miR-143 may be a hopeful candidate as an RNA medicine for the treatment of colorectal tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19921579,"Year":2009,"Title":"[Clinicopathological significance of microRNA-21 and miR-125 expression in colorectal cancer].","Abstract":"OBJECTIVE: To investigate the expression of microRNA(miR)-21 and miR-125 in colorectal cancer (CRC) and its relationship with clinicopathological features. METHODS: Quantitative real-time PCR was applied to examine the expression of miR-21 and miR-125 in 100 primary CRC specimens which were diagnosed and operated in West China Hospital between 2006 and 2007, in comparison with the corresponding normal mucosa specimens. The relationship between the expression of miRNAs and clinicopathological features was analyzed. RESULTS: The expression of miR-21 in CRC was up-regulated by 2.3 times compared to normal mucosa (P =0.025), while the expression of miR-125 was down-regulated by 3.3 times in comparison with normal mucosa (P =0.005). Furthermore, the expression of miR-21 was related to TNM stage (P =0.028) and local invasion (P =0.023). On the other hand, no significant relationship was found between the expression of miR-125 and clinicopathological features (P >0.05). CONCLUSION: The over-expression of miR-21 may play a role in the development and progression of CRC, while miR-125 may not be related to the pathogenesis of CRC.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19826040,"Year":2009,"Title":"microRNA-21 negatively regulates Cdc25A and cell cycle progression in colon cancer cells.","Abstract":"microRNAs (miRNA) are small noncoding RNAs that participate in diverse biological processes by suppressing target gene expression. Altered expression of miR-21 has been reported in cancer. To gain insights into its potential role in tumorigenesis, we generated miR-21 knockout colon cancer cells through gene targeting. Unbiased microarray analysis combined with bioinformatics identified cell cycle regulator Cdc25A as a miR-21 target. miR-21 suppressed Cdc25A expression through a defined sequence in its 3'-untranslated region. We found that miR-21 is induced by serum starvation and DNA damage, negatively regulates G(1)-S transition, and participates in DNA damage-induced G(2)-M checkpoint through down-regulation of Cdc25A. In contrast, miR-21 deficiency did not affect apoptosis induced by a variety of commonly used anticancer agents or cell proliferation under normal cell culture conditions. Furthermore, miR-21 was found to be underexpressed in a subset of Cdc25A-overexpressing colon cancers. Our data show a role of miR-21 in modulating cell cycle progression following stress, providing a novel mechanism of Cdc25A regulation and a potential explanation of miR-21 in tumorigenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19737943,"Year":2009,"Title":"Association of inflammation-related and microRNA gene expression with cancer-specific mortality of colon adenocarcinoma.","Abstract":"PURPOSE: Inflammatory genes and microRNAs have roles in colon carcinogenesis; therefore, they may provide useful biomarkers for colon cancer. This study examines the potential clinical utility of an inflammatory gene expression signature as a prognostic biomarker for colon cancer in addition to previously examined miR-21 expression. EXPERIMENTAL DESIGN: Quantitative reverse transcriptase-PCR. was used to measure the expression of 23 inflammatory genes in colon adenocarcinomas and adjacent noncancerous tissues from 196 patients. These data were used to develop models for cancer-specific mortality on a training cohort (n = 57), and this model was tested in both a test (n = 56) and a validation (n = 83) cohort. Expression data for miR-21 were available for these patients and were compared and combined with inflammatory gene expression. RESULTS: PRG1, IL-10, CD68, IL-23a, and IL-12a expression in noncancerous tissue, and PRG1, ANXA1, IL-23a, IL-17a, FOXP3, and HLA-DRA expression in tumor tissues were associated with poor prognosis based on Cox regression (/Z-score/ >1.5) and were used to generate the inflammatory risk score (IRS). IRS was associated with cancer-specific mortality in the training, test (P = 0.01), and validation (P = 0.02) cohorts. This association was strong for stage II cases (P = 0.002). Expression of miR-21 was associated with IL-6, IL-8, IL-10, IL-12a, and NOS2a, providing evidence that the function of this microRNA and these inflammatory genes are linked. Both IRS and miR-21 expression were independently associated with cancer-specific mortality, including stage II patients alone. CONCLUSION: IRS and miR-21 expression are independent predictors of colon cancer prognosis and may provide a clinically useful tool to identify high-risk patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19593777,"Year":2009,"Title":"MicroRNA expression profiling of human metastatic cancers identifies cancer gene targets.","Abstract":"Small non-coding microRNAs (miRNAs) contribute to cancer development and progression, and are differentially expressed in normal tissues and cancers. However, the specific role of miRNAs in the metastatic process is still unknown. To seek a specific miRNA expression signature characterizing the metastatic phenotype of solid tumours, we performed a miRNA microarray analysis on 43 paired primary tumours (ten colon, ten bladder, 13 breast, and ten lung cancers) and one of their related metastatic lymph nodes. We identified a metastatic cancer miRNA signature comprising 15 overexpressed and 17 underexpressed miRNAs. Our results were confirmed by qRT-PCR analysis. Among the miRNAs identified, some have a well-characterized association with cancer progression, eg miR-10b, miR-21, miR-30a, miR-30e, miR-125b, miR-141, miR-200b, miR-200c, and miR-205. To further support our data, we performed an immunohistochemical analysis for three well-defined miRNA gene targets (PDCD4, DHFR, and HOXD10 genes) on a small series of paired colon, breast, and bladder cancers, and one of their metastatic lymph nodes. We found that the immunohistochemical expression of these targets significantly follows the corresponding miRNA deregulation. Our results suggest that specific miRNAs may be directly involved in cancer metastasis and that they may represent a novel diagnostic tool in the characterization of metastatic cancer gene targets.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19547998,"Year":2009,"Title":"Differential expression of microRNA 181b and microRNA 21 in hyperplastic polyps and sessile serrated adenomas of the colon.","Abstract":"This study was designed to analyse the potential diagnostic value of miR-181b and miR-21 for discriminating hyperplastic polyps (HP) from sessile serrated adenomas (SSA) without cytologic dysplasia. Using real-time polymerase chain reaction expression levels of miR-181b and miR-21 in 18 HPs, 19 SSAs without cytologic dysplasia and 20 normal colonic mucosal specimens were examined. In addition, 20 colorectal cancers specimen were analysed for miR-181b expression. Data were normalised to RNU48 as an internal control. A differential expression of miR-181b and miR-21 was found in HPs, SSAs, and normal colonic mucosa with highest expression levels in SSAs. Levels of miR-181b but not miR-21 differed in HPs and normal mucosa. SSAs exhibited both significantly higher miR-181b levels (up to 2.01-fold; P < 0.001) and miR-21 levels (up to 1.82-fold; P = 0.011) than HPs. In contrast to HPs, SSAs are characterised by high levels of miR-181b and miR-21 expression. However, due to the overlap of values, miR-181b and miR-21 evaluation did not allow discrimination of the two lesions in every case.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19509156,"Year":2009,"Title":"Locked nucleic acid in situ hybridization analysis of miR-21 expression during colorectal cancer development.","Abstract":"PURPOSE: To better understand microRNA miR-21 function in carcinogenesis, we analyzed miR-21 expression patterns in different stages of colorectal cancer development using in situ hybridization (ISH). EXPERIMENTAL DESIGN: Locked nucleic acid (LNA)/DNA probes and a biotin-free tyramide signal amplification system were used in ISH analyses of miRNA expression. Conditions for specific detection of miR-21 were determined using human cell lines and miR-21-expressing lentiviral vectors. Expression was determined in 39 surgically excised colorectal tumors and 34 endoscopically resected colorectal polyps. RESULTS: In the surgical samples, miR-21 expression was much higher in colorectal cancers than in normal mucosa. Strong miR-21 expression was also observed in cancer-associated stromal fibroblasts, suggesting miR-21 induction by cancer-secreted cytokines. Protein expression of PDCD4, a miR-21 target, was inversely correlated with miR-21 expression, confirming that miR-21 is indeed a negative regulator of PDCD4 in vivo. In the endoscopic samples, miR-21 expression was very high in malignant adenocarcinomas but was not elevated in nontumorigenic polyps. Precancerous adenomas also frequently showed miR-21 up-regulation. CONCLUSION: Using the LNA-ISH system for miRNA detection, miR-21 was detectable in precancerous adenomas. The frequency and extent of miR-21 expression increased during the transition from precancerous colorectal adenoma to advanced carcinoma. Expression patterns of miR-21 RNA and its target, tumor suppressor protein PDCD4, were mutually exclusive. This pattern may have clinical application as a biomarker for colorectal cancer development and might be emphasized by self-reinforcing regulatory systems integrated with the miR-21 gene, which has been previously shown in cell culture.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":19047896,"Year":2009,"Title":"Clinical, pathologic, and molecular features of early-onset colorectal carcinoma.","Abstract":"The incidence of colorectal carcinoma has increased among patients <40 years of age for unclear reasons. In this study, we describe the clinical, pathologic, and molecular features of colorectal carcinomas that developed in young patients. We compiled a study group of 24 patients <40 years of age with colorectal carcinoma, and 45 patients > or =40 years of age served as controls. Cases were evaluated for clinical risk factors of malignancy and pathologic features predictive of outcome. The tumors were immunohistochemically stained for O6-methylguanine methyltransferase, MLH-1, MSH-2, MSH-6, beta-catenin, chemokine (C-X-C motif) receptor 4, epidermal growth factor receptor, TP53, p16, survivin, and alpha-methylacyl-CoA racemase; assessed for microsatellite instability and mutations in beta-catenin, APC, EGFR, PIK3CA, KRAS, and BRAF; evaluated for micro-RNA expression (miR-21, miR-20a, miR-183, miR-192, miR-145, miR-106a, miR-181b, and miR-203); and examined for evidence of human papillomavirus infection. One study patient each had ulcerative colitis and hereditary nonpolyposis colorectal cancer. Ninety-two percent of tumors from young patients occurred in the distal colon (P=0.006), particularly the rectum (58%, P=0.02), and 75% were stage III or IV. Tumors from young patients showed more frequent lymphovascular (81%, P=0.03) and/or venous (48%, P=0.003) invasion, an infiltrative growth pattern (81%, P=0.03), and alpha-methylacyl-CoA racemase expression (83%, P=0.02) compared with controls. Carcinomas in this group showed significantly increased expression of miR-21, miR-20a, miR-145, miR-181b, and miR-203 (P< or =0.005 for all comparisons with controls). These results indicate that early-onset carcinomas commonly show pathologic features associated with aggressive behavior. Posttranslational regulation of mRNA and subsequent protein expression may be particularly important to the development of colorectal carcinomas in young patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":18695884,"Year":2008,"Title":"Micro-RNAs miR125b and miR137 are frequently upregulated in response to capecitabine chemoradiotherapy of rectal cancer.","Abstract":"There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":18508928,"Year":2008,"Title":"MicroRNA-21 targets Sprouty2 and promotes cellular outgrowths.","Abstract":"The posttranscriptional regulator, microRNA-21 (miR-21), is up-regulated in many forms of cancer, as well as during cardiac hypertrophic growth. To understand its role, we overexpressed it in cardiocytes where it revealed a unique type of cell-to-cell \"linker\" in the form of long slender outgrowths and branches. We subsequently confirmed that miR-21 directly targets and down-regulates the expression of Sprouty2 (SPRY2), an inhibitor of branching morphogenesis and neurite outgrowths. We found that beta-adrenergic receptor (betaAR) stimulation induces up-regulation of miR-21 and down-regulation of SPRY2 and is, likewise, associated with connecting cell branches. Knockdown of SPRY2 reproduced the branching morphology in cardiocytes, and vice versa, knockdown of miR-21 using a specific 'miRNA eraser' or overexpression of SPRY2 inhibited betaAR-induced cellular outgrowths. These structures enclose sarcomeres and connect adjacent cardiocytes through functional gap junctions. To determine how this aspect of miR-21 function translates in cancer cells, we knocked it down in colon cancer SW480 cells. This resulted in disappearance of their microvillus-like protrusions accompanied by SPRY2-dependent inhibition of cell migration. Thus, we propose that an increase in miR-21 enhances the formation of various types of cellular protrusions through directly targeting and down-regulating SPRY2.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":18230780,"Year":2008,"Title":"MicroRNA expression profiles associated with prognosis and therapeutic outcome in colon adenocarcinoma.","Abstract":"CONTEXT: MicroRNAs have potential as diagnostic biomarkers and therapeutic targets in cancer. No study has evaluated the association between microRNA expression patterns and colon cancer prognosis or therapeutic outcome. OBJECTIVE: To identify microRNA expression patterns associated with colon adenocarcinomas, prognosis, or therapeutic outcome. DESIGN, SETTING, AND PATIENTS: MicroRNA microarray expression profiling of tumors and paired nontumorous tissues was performed on a US test cohort of 84 patients with incident colon adenocarcinoma, recruited between 1993 and 2002. We evaluated associations with tumor status, TNM staging, survival prognosis, and response to adjuvant chemotherapy. Associations were validated in a second, independent Chinese cohort of 113 patients recruited between 1991 and 2000, using quantitative reverse transcription polymerase chain reaction assays. The final date of follow-up was December 31, 2005, for the Maryland cohort and August 16, 2004, for the Hong Kong cohort. MAIN OUTCOME MEASURES: MicroRNAs that were differentially expressed in tumors and microRNA expression patterns associated with survival using cancer-specific death as the end point. RESULTS Thirty-seven microRNAs were differentially expressed in tumors from the test cohort. Selected for validation were miR-20a, miR-21, miR-106a, miR-181b, and miR-203, and all 5 were enriched in tumors from the validation cohort (P < .001). Higher miR-21 expression was present in adenomas (P = .006) and in tumors with more advanced TNM staging (P < .001). In situ hybridization demonstrated miR-21 to be expressed at high levels in colonic carcinoma cells. The 5-year cancer-specific survival rate was 57.5% for the Maryland cohort and was 49.5% for the Hong Kong cohort. High miR-21 expression was associated with poor survival in both the training (hazard ratio, 2.5; 95% confidence interval, 1.2-5.2) and validation cohorts (hazard ratio, 2.4; 95% confidence interval, 1.4-3.9), independent of clinical covariates, including TNM staging, and was associated with a poor therapeutic outcome. CONCLUSIONS: Expression patterns of microRNAs are systematically altered in colon adenocarcinomas. High miR-21 expression is associated with poor survival and poor therapeutic outcome.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":18196926,"Year":2007,"Title":"Altered expression of miR-21, miR-31, miR-143 and miR-145 is related to clinicopathologic features of colorectal cancer.","Abstract":"OBJECTIVES: Development and metastases of colorectal cancer (CRC) are characterized by multiple genetic alterations. MicroRNAs (miRNAs) are endogenously expressed regulatory noncoding RNAs. Previous, mainly preclinical studies showed altered expression levels of several miRNAs in CRC. METHODS: In our study, the expression levels of miR-21, miR-31, miR-143 and miR-145 in 29 primary colorectal carcinomas and 6 non-tumor adjacent tissue specimens were examined by real-time polymerase chain reaction. miRNA expression levels were also correlated with commonly used clinicopath-ologic features of CRC. RESULTS: Expression levels of analyzed miRNAs significantly differed among tumors and adjacent non-tumor tissues: miR-21 (p = 0.0001) and miR-31 (p = 0.0006) were upregulated, and miR-143 (p = 0.011) and miR-145 (p = 0.003) were downregulated in tumors. For the first time, a high expression of miR-21 was associated with lymph node positivity (p = 0.025) and the development of distant metastases (p = 0.009) in CRC patients. Thus, expression of miR-21 correlated with CRC clinical stage (p = 0.032). Furthermore, tumors >50 mm in maximal tumor diameter were characterized by lower expression of miR-143 (p = 0.006) and miR-145 (p = 0.003). We found no correlation between analyzed miRNAs and serum levels of carcinoembryonic antigen. CONCLUSION: Our results suggest possible roles of miR-21, miR-31, miR-143 and miR-145 in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":17968323,"Year":2008,"Title":"MicroRNA-21 (miR-21) post-transcriptionally downregulates tumor suppressor Pdcd4 and stimulates invasion, intravasation and metastasis in colorectal cancer.","Abstract":"Tumor-suppressor Pdcd4 inhibits transformation and invasion and is downregulated in cancers. So far, it has not been studied as to whether miRNAs, suppressing target expression by binding to the 3'-UTR, regulate Pdcd4 or invasion. The present study was conducted to investigate the regulation of Pdcd4, and invasion/intra-vasation, by miRNAs. A bioinformatics search revealed a conserved target-site for miR-21 within the Pdcd4-3'-UTR at 228-249 nt. In 10 colorectal cell lines, an inverse correlation of miR-21 and Pdcd4-protein was observed. Transfection of Colo206f-cells with miR-21 significantly suppressed a luciferase-reporter containing the Pdcd4-3'-UTR, whereas transfection of RKO with anti-miR-21 increased activity of this construct. This was abolished when a construct mutated at the miR-21/nt228-249 target site was used instead. Anti-miR-21-transfected RKO cells showed an increase of Pdcd4-protein and reduced invasion. Moreover, these cells showed reduced intra-vasation and lung metastasis in a chicken-embryo-metastasis assay. In contrast, overexpression of miR-21 in Colo206f significantly reduced Pdcd4-protein amounts and increased invasion, while Pdcd4-mRNA was unaltered. Resected normal/tumor tissues of 22 colorectal cancer patients demonstrated an inverse correlation between miR-21 and Pdcd4-protein. This is the first study to show that Pdcd4 is negatively regulated by miR-21. Furthermore, it is the first report to demonstrate that miR-21 induces invasion/intravasation/metastasis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":17702597,"Year":2007,"Title":"Modification of miR gene expression pattern in human colon cancer cells following exposure to 5-fluorouracil in vitro.","Abstract":"MicroRNAs (miRNAs) are small noncoding RNA molecules produced by miR genes which are able to control the expression of a large number of cellular proteins by targeting mRNAs of protein coding genes. It has been suggested that modification of miR gene expression could be an important factor in the development and maintenance of the neoplastic state. It is also reasonable to hypothesize that antineoplastic drugs could be able to alter miR gene expression pattern since most of them are able to interfere with nucleic acid metabolism and gene expression. Here we show that 5-fluorouracil (5-FU), a classical antimetabolite largely used in the clinic, is able to change significantly the expression of several miR genes. In colon cancer cells, at a clinically relevant concentration, the drug up-regulates or down-regulates in vitro the expression of 19 and 3 miR genes, respectively, by a factor of not less than two-fold. In some instances, 5-FU up-regulates miR genes that are already over-expressed in neoplastic tissues, including, for example, miR-21 that is associated with anti-apoptotic functions characterizing malignant cells. In this case, it is possible that drug-induced miR gene dysregulation could be the expression of cellular response to the toxic effects of the agent. On the contrary, in other instances the drug influences the expression of miR genes in a direction that is opposite to that induced by neoplastic transformation. A typical example is provided by miR-200b, that is up-regulated in various tumors and down-regulated by treatment with the antimetabolite. Noteworthy, it is known that miR-200b suppresses a gene that codes for a protein tyrosine phosphatase (PTPN12) that inactivates products of oncogenes, such as c-Abl, Src or Ras. In conclusion, the present results support the hypothesis that 5-FU can alter profoundly miR gene expression pattern. This effect could be responsible, at least in part, of the multi-target pleiotropic influence manifested by the drug on malignant cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-21"}
{"PMID":26804172,"Year":2016,"Title":"Adenomatous polyposis coli (APC) regulates miR17-92 cluster through beta-catenin pathway in colorectal cancer.","Abstract":"Adenomatous polyposis coli (APC) mutation is the most common genetic change in sporadic colorectal cancer (CRC). Although deregulations of miRNAs have been frequently reported in this malignancy, APC-regulated miRNAs have not been extensively documented. Here, by using an APC-inducible cell line and array analysis, we identified a total of 26 deregulated miRNAs. Among them, members of miR-17-92 cluster were dramatically inhibited by APC and induced by enforced expression of beta-catenin. Furthermore, we demonstrate that activated beta-catenin resulted from APC loss binds to and activates the miR-17-92 promoter. Notably, enforced expression of miR-19a overrides APC tumor suppressor activity, and knockdown of miR-19a in cancer cells with compromised APC function reduced their aggressive features in vitro. Finally, we observed that expression of miR-19a significantly correlates with beta-catenin levels in colorectal cancer specimens, and it is associated to the aggressive stage of tumor progression. Thus, our study reveals that miR-17-92 cluster is directly regulated by APC/beta-catenin pathway and could be a potential therapeutic target in colon cancers with aberrant APC/beta-catenin signaling.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-17"}
{"PMID":29496262,"Year":2018,"Title":"Colorectal cancer cell-derived exosomes containing miR-10b regulate fibroblast cells via the PI3K/Akt pathway.","Abstract":"BACKGROUND: Cancer-associated fibroblasts (CAFs) contribute to the proliferation of colorectal cancer(CRC) cells. However, the mechanism by which CAFs develop in the tumor microenvironment remains unknown. Exosomes may be involved in activating CAFs. METHODS: Using a miRNA expression profiling array, we determined the miRNA expression profile of secretory exosomes in CRC cells and then identified potential miRNAs with significant differential expression compared to normal cells via enrichment analysis. Predicted targets of candidate miRNAs were then assessed via bioinformatics analysis. Realtime qPCR, western blot, and cell cycle analyses were performed to evaluate the role of candidate exosomal miRNAs. Luciferase reporter assays were applied to confirm whether candidate exosomal miRNAs control target pathway expression. A CRC xenograft mouse model was constructed to evaluate tumor growth in vivo. RESULTS: Exosomes from CRC cells contained significantly higher levels of miR-10b than did exosomes from normal colorectal epithelial cells. Moreover, exosomes containing miR-10b were transferred to fibroblasts. Bioinformatics analysis identified PIK3CA, as a potential target of miR-10b. Luciferase reporter assays confirmed that miR-10b directly inhibited PIK3CA expression. Co-culturing fibroblasts with exosomes containing miR-10b significantly suppressed PIK3CA expression and decreased PI3K/Akt/mTOR pathway activity. Finally, exosomes containing miR-10b reduced fibroblast proliferation but promoted expression of TGF-beta and SM alpha-actin, suggesting that exosomal miR-10b may activate fibroblasts to become CAFs that express myofibroblast markers. These activated fibroblasts were able to promote CRC growth in vitro and in vivo. CONCLUSION: CRC-derived exosomes actively promote disease progression by modulating surrounding stromal cells, which subsequently acquire features of CAFs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-10"}
{"PMID":23322774,"Year":2013,"Title":"MicroRNA-31 activates the RAS pathway and functions as an oncogenic MicroRNA in human colorectal cancer by repressing RAS p21 GTPase activating protein 1 (RASA1).","Abstract":"MicroRNAs (miRNAs) are known to play a vital role in colorectal cancer. We found a widespread disruption in miRNA expression during colorectal tumorigenesis using microarray and quantitative RT-PCR analysis; of the 161 miRNAs altered in colorectal cancer compared with normal adjacent tissue samples, miR-31 was the most significantly dysregulated. We identified candidate targets of miR-31 using bioinformatics approaches and validated RAS p21 GTPase activating protein 1 (RASA1) as a direct target. First, we found an inverse correlation between miR-31 and RASA1 protein levels in vivo. Second, in vitro evidence demonstrated that RASA1 expression was significantly decreased by treatment with pre-miR-31-LV, whereas anti-miR-31-LV treatment increased RASA1 protein levels. Third, a luciferase reporter assay confirmed that miR-31 directly recognizes a specific location within the 3'-untranslated region of RASA1 transcripts. Furthermore, the biological consequences of miR-31 targeting RASA1 were examined by the cell proliferation assay in vitro and by the immunodeficient mouse xenograft tumor model in vivo. Taken together, our results demonstrate for the first time that miR-31 plays a significant role in activating the RAS signaling pathway through the inhibition of RASA1 translation, thereby improving colorectal cancer cell growth and stimulating tumorigenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-31"}
{"PMID":30790680,"Year":2019,"Title":"Tumor suppressor miR-215 counteracts hypoxia-induced colon cancer stem cell activity.","Abstract":"Cancer stem cells, also known as tumor-initiating cells (TICs), are a population of aggressive and self-renewing cells that are responsible for the initiation and progression of many cancers, including colorectal carcinoma. Intratumoral hypoxia, i.e. reduced oxygen supply following uncontrolled proliferation of cancer cells, is thought to support TIC activity by inducing specific hypoxia-responsive mechanisms that are not yet entirely understood. Using previously established and fully characterized patient-derived TIC cultures, we could observe increased sphere and colony formation under hypoxic conditions. Mechanistically, microRNA (miRNA)-profiling experiments allowed us to identify miR-215 as one of the main hypoxia-induced miRNAs in primary colon TICs. Through stable overexpression of miR-215, followed by a set of functional in vitro and in vivo investigations, miR-215 was pinpointed as a negative feedback regulator, working against the TIC-promoting effects of hypoxia. Furthermore, we could single out LGR5, a bona fide marker of non-neoplastic intestinal stem cells, as a downstream target of hypoxia/miR-215 signaling. The strong tumor- and TIC-suppressor potential of miR-215 and the regulatory role of the hypoxia/miR-215/LGR5 axis may thus represent interesting points of attack for the development of innovative anti-CSC therapy approaches.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-215"}
{"PMID":30106114,"Year":2018,"Title":"miR197 promotes the invasion and migration of colorectal cancer by targeting insulinlike growth factorbinding protein 3.","Abstract":"The incidence and mortality of colorectal cancer (CRC) have been rising rapidly in China. A number of miRNAs have been confirmed to be involved in diverse biological processes of CRC. However, whether miR197 plays a role in migration and invasion of CRC has never been explored. In the present study Transwell chambers were used in in vitro migration and invasion assays. Dual-luciferase reporter assay was employed to confirm the target of miR197. RTPCR and IHC staining were performed to quantify miR197 and IGFBP3 expression, respectively. Clinicopathological features were collected for statistical analysis. We observed that the overexpression of miR197 significantly promoted migration and invasion in 3 CRC cell lines including HCT8, HCT116 and SW480 (P<0.05), while the inhibition of miR197 weakened both biological processes (P<0.05). In bioinformatics and dual-luciferase reporter assay, luciferase activities of IGFBP3WTtransfected cells significantly decreased upon miR197 overexpression and this inhibitory effect was abolished when miR197 binding region in IGFBP3 3'UTR was mutated, which indicated that miR197 directly suppressed the expression of IGFBP3 in CRC cells by targeting its 3'UTR. Downregulation of the expression of IGFBP3 by using targeted siRNA led to significant enhancement of cell migration and invasion in two CRC cell lines including HCT8 and HCT116 (P<0.05). Finally, in cancerous tissues of CRC patients, the miR197 level was inversely correlated with the expression of IGFBP3 (P=0.026), which indicated that miR197 may modulate cell migration and invasion by targeting IGFBP3 in CRC patients. In conclusion, we revealed that miR197 modulates IGFBP3 and therefore plays a critical role in regulating CRC migration and invasion.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-197"}
{"PMID":22930392,"Year":2013,"Title":"Loss of miR-101 expression promotes Wnt/beta-catenin signalling pathway activation and malignancy in colon cancer cells.","Abstract":"Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in Western countries. Although the aberrant expression of several microRNAs (oncomiRs) is associated with CRC progression, the molecular mechanisms of this phenomenon are still under investigation. Here we show that miR-101 expression is differentially impaired in CRC specimens, depending on tumour grade. miR-101 re-expression suppresses cell growth in 3D, hypoxic survival and invasive potential in CRC cells showing low levels of miR-101. Additionally, we provide molecular evidence of a bidirectional regulatory mechanism between miR-101 expression and important CRC pro-malignant features, such as inflammation, activation of the Wnt/beta-catenin signalling pathway and epithelial-mesenchymal transition (EMT). We then propose that up-regulated miR-101 may function as a tumour suppressor in CRC and that its pharmacological restoration might hamper the aggressive behaviour of CRC in vivo. MiR-101 expression may also represent a cancer biomarker for CRC diagnosis and prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-101"}
{"PMID":23292866,"Year":2013,"Title":"Aberrant expression of miR-199a-3p and its clinical significance in colorectal cancers.","Abstract":"Aberrant miR-199a-3p expression has been reported in several cancers. However, the clinical significance of miR-199a-3p in human colorectal cancer has not been addressed. In this study, we detected miR-199a-3p expression in 92 colorectal cancer cases to evaluate its clinicopathologic characteristics in colorectal cancer. We showed that miR-199a-3p expression was significantly upregulated in cancer tissues than NATs. Clinicopathologic analysis revealed that high miR-199a-3p expression contributed to more advanced lymphatic invasion, lymph node metastasis, liver metastases and late TNM stage in colorectal cancer. Kaplan-Meier analysis showed that high expression of miR-199a-3p could lead to a significantly shorter overall survival rate. Cox's proportional hazards model also indicated that the high expression of miR-199a-3p could serve as an independent and significant prognostic factor for survival. We transfected miR-199a-3p inhibitor into SW480 cells and observed that miR-199a-3p inhibitor could markedly inhibit the cell proliferation. Flow cytometry analysis also found that miR-199a-3p inhibitor could cause G0/G1 arrest, decreased percentage of S and G2/M phase and induce more cell apoptosis in SW480 cells. These results suggested that miR-199a-3p may serve as an efficient biomarker for diagnosis and novel prognostic indicator in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-199"}
{"PMID":26954494,"Year":2016,"Title":"Support Vector Machine Based on microRNA Expression Profiles to Predict Histological Origin of Ampullary Carcinoma: Case Report of a Patient Affected From Adenocarcinoma of the Papilla of Vater With Lynch Syndrome.","Abstract":"Adenocarcinomas of Vater's papilla (PVAC) may originate from either the pancreatic duct or the intestinal epithelium. Conflicting data have been reported about the frequency of the 2 anatomical entities and their influence on patients' prognosis. To ascertain the anatomical origin of PVAC in a family member of a Lynch syndrome kindred, we searched for microRNA (miRNA) expression profiles on resected tumor specimens. The support vector machine was trained on our previous miRNAs expression data sets of pancreatic and colorectal tissue samples and used to classify the site of origin of the tumor in our patient. The support vector machine worked by contrasting the profiles of miRNAs in patients with pancreatic ductal and colorectal cancers to that of our patient, which was finally classified as pancreatic ductal adenocarcinoma accordingly to alterations of 55 miRNAs. The PVAC might be originated from ductal epithelium rather than from the intestinal mucosa of the papilla in the case at issue. Alteration of miR-548b-3p, miR-551a, miR-21, miR-92a, miR-let-7i, and miR-181a* emerged as potentially associated with cancer genetic susceptibility in PVAC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-92"}
{"PMID":26148070,"Year":2015,"Title":"Oncogenic Role of miR-15a-3p in 13q Amplicon-Driven Colorectal Adenoma-to-Carcinoma Progression.","Abstract":"Progression from colorectal adenoma to carcinoma is strongly associated with an accumulation of genomic alterations, including gain of chromosome 13. This gain affects the whole q arm and is present in 40%-60% of all colorectal cancers (CRCs). Several genes located at this amplicon are known to be overexpressed in carcinomas due to copy number dosage. A subset of these genes, including the mir-17~92 cluster, are functionally involved in CRC development. The present study set out to explore whether apart from mir-17~92, other miRNAs located at the 13q amplicon show a copy number dependent dosage effect that may contribute to 13q-driven colorectal adenoma-to-carcinoma progression. Integration of publically available miRNA expression, target mRNA expression and DNA copy number data from 125 CRCs yielded three miRNAs, miR-15a, -17, and -20a, of which high expression levels were significantly correlated with a 13q gain and which influenced target mRNA expression. These results could be confirmed by qRT-PCR in a series of 100 colon adenomas and carcinomas.Functional analysis of both mature miRNAs encoded by mir-15a, i.e. miR-15a-5p and miR-15a-3p, showed that silencing of miR-15a-3p significantly inhibited viability of CRC cells. Integration of miR-15a expression levels with mRNA expression data of predicted target genes identified mitochondrial uncoupling protein 2 (UCP2) and COP9 signalosome subunit 2 (COPS2) as candidates with significantly decreased expression in CRCs with 13q gain. Upon silencing of miR-15a-3p, mRNA expression of both genes increased in CRC cells, supporting miR-15a-3p mediated regulation of UPC2 and COPS2 expression. In conclusion, significant overexpression of miR-15a-3p due to gain of 13q is functionally relevant in CRC, with UCP2 and COPS2 as candidate target genes. Taken together our findings suggest that miR-15a-3p may contribute to adenoma-to-carcinoma progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-20"}
{"PMID":20603437,"Year":2011,"Title":"A let-7 microRNA-binding site polymorphism in 3'-untranslated region of KRAS gene predicts response in wild-type KRAS patients with metastatic colorectal cancer treated with cetuximab monotherapy.","Abstract":"PURPOSE: recent studies have found that KRAS mutations predict resistance to monoclonal antibodies targeting the epidermal growth factor receptor in metastatic colorectal cancer (mCRC). A polymorphism in a let-7 microRNA complementary site (lcs6) in the KRAS 3' untranslated region (UTR) is associated with an increased cancer risk in non-small-cell lung cancer and reduced overall survival (OS) in oral cancers. We tested the hypothesis whether this polymorphism may be associated with clinical outcome in KRAS wild-type (KRASwt) mCRC patients treated with cetuximab monotherapy. PATIENTS AND METHODS: the presence of KRAS let-7 lcs6 polymorphism was evaluated in 130 mCRC patients who were enrolled in a phase II study of cetuximab monotherapy (IMCL-0144). Genomic DNA was extracted from dissected formalin-fixed paraffin-embedded tumor tissue, KRAS mutation status and polymorphism were assessed using direct sequencing and PCR restriction fragment length polymorphism technique. RESULTS: KRAS let-7 lcs6 polymorphism was found to be related to object response rate (ORR) in mCRC patients whose tumors had KRASwt. The 12 KRASwt patients harboring at least a variant G allele (TG or GG) had a 42% ORR compared with a 9% ORR in 55 KRASwt patients with let-7 lcs6 TT genotype (P = 0.02, Fisher's exact test). KRASwt patients with TG/GG genotypes had trend of longer median progression-free survival (3.9 versus 1.3 months) and OS (10.7 versus 6.4 months) compared to those with TT genotypes. CONCLUSIONS: these results are the first to indicate that the KRAS 3'UTR polymorphism may predict for cetuximab responsiveness in KRASwt mCRC patients, which warrants validation in other clinical trials.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":24778034,"Year":2014,"Title":"miR-592 and miR-552 can distinguish between primary lung adenocarcinoma and colorectal cancer metastases in the lung.","Abstract":"BACKGROUND/AIM: Distinguishing between primary and metastatic adenocarcinomas in the lung may sometimes be difficult by conventional histopathological methods. In addition, novel biomarkers are needed for the more accurate subtyping of primary lung carcinomas. MATERIALS AND METHODS: MicroRNA microarrays were performed on 26 primary lung adenocarcinomas, 3 squamous cell carcinomas, 6 small cell lung cancers (SCLCs), and 2 colorectal cancer metastases in the lung. RESULTS: Forty-four microRNAs differentially expressed between three histological subtypes at p<10(-6) predicted histology with 100% accuracy in 100 randomly drawn datasets. Prominent among differentially expressed genes were miR-375, miR-217 and miR-216a, which were found overexpressed in SCLC compared to lung adenocarcinomas. Lung adenocarcinomas overexpressed miR-29b-1, miR-375, miR-2110, miR-29c-star, 199b-5p, and 146b-3p and underexpressed miR-617, miR-205-star, and miR-1246 compared to squamous cell carcinomas. In primary vs. metastatic lung adenocarcinomas, miR-552 and miR-592 were differentially expressed at p<10(-6); the level of expression of miR-552 in colorectal cancer metastases was 39-times higher and that of miR-592 was six-times higher. Furthermore, microRNA profiles of primary colorectal cancer in our database indicated that these two microRNAs were overexpressed in primary colorectal cancer relative to primary lung adenocarcinomas. CONCLUSION: MicroRNA profiles predict the histology of primary lung carcinomas, and differentiate between primary lung adenocarcinomas and colorectal cancer metastases.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-592"}
{"PMID":27922690,"Year":2017,"Title":"MicroRNA-152 inhibits tumor cell growth by directly targeting RTKN in hepatocellular carcinoma.","Abstract":"Hepatocellular carcinoma (HCC) is the most common form of adult liver cancer and accounts for approximately 90% of all cases of primary liver cancer annually. Rhotekin (RTKN), which functions as a cancer promoter, can be frequently detected in many human cancers, including gastric cancer, colorectal carcinoma and bladder carcinoma. The aim of this study was to investigate the role of RTKN in HCC. Using HCC cells and tissues from patients with liver cancer, we demonstrated that RTKN was significantly increased in HCC. To examine the effect of RTKN on HCC, RTKN overexpressed or silenced HepG2 and Hep3B cells were constructed. Cell proliferation and apoptosis were measured by RT-PCR and flow cytometry. The results showed that RTKN can function as an oncogene and promote the proliferation, while inhibiting apoptosis, of HepG2 and Hep3B cells. Furthermore, we identified that RTKN is a direct gene target of miR-152. miR-152 can reverse the growth promoting effect of RTKN on HCC cells through G2/M phase arrest and nuclear factor-kappaB (NF-kappaB) signal inhibition. In conclusion, our research identified that miRNA-152 can inhibit tumor cell growth by targeting RTKN in HCC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-152"}
{"PMID":21722265,"Year":2011,"Title":"Invasion front-specific expression and prognostic significance of microRNA in colorectal liver metastases.","Abstract":"The tumor edge of colorectal cancer and its adjacent peritumoral tissue is characterized by an invasion front-specific expression of genes that contribute to angiogenesis or epithelial-to-mesenchymal transition. Dysregulation of these genes has a strong impact on the invasion behavior of tumor cells. However, the invasion front-specific expression of microRNA (miRNA) still remains unclear. Therefore, the aim of the present study was to investigate miRNA expression patterns at the invasion front of colorectal liver metastases. Laser microdissection of colorectal liver metastases was performed to obtain separate tissue compartments from the tumor center, tumor invasion front, liver invasion front and pure liver parenchyma. Microarray expression analysis revealed 23 miRNA downregulated in samples from the tumor invasion front with respect to the same miRNA in the liver, the liver invasion front or the tumor center. By comparing samples from the liver invasion front with samples from pure liver parenchyma, the tumor invasion front and the tumor center, 13 miRNA were downregulated. By quantitative RT-PCR, we validated the liver invasion front-specific downregulation of miR-19b, miR-194, let-7b and miR-1275 and the tumor invasion front-specific downregulation of miR-143, miR- 145, let-7b and miR-638. Univariate analysis demonstrated that enhanced expression of miR-19b and miR-194 at the liver invasion front, and decreased expression of let-7 at the tumor invasion front, is an adverse prognostic marker of tumor recurrence and overall survival. In conclusion, the present study suggests that invasion front-specific downregulation of miRNA in colorectal liver metastases plays a pivotal role in tumor progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-143"}
{"PMID":29795787,"Year":2018,"Title":"Interaction between Host MicroRNAs and the Gut Microbiota in Colorectal Cancer.","Abstract":"Although variation in gut microbiome composition has been linked with colorectal cancer (CRC), the factors that mediate the interactions between CRC tumors and the microbiome are poorly understood. MicroRNAs (miRNAs) are known to regulate CRC progression and are associated with patient survival outcomes. In addition, recent studies suggested that host miRNAs can also regulate bacterial growth and influence the composition of the gut microbiome. Here, we investigated the association between miRNA expression and microbiome composition in human CRC tumor and normal tissues. We identified 76 miRNAs as differentially expressed (DE) in tissue from CRC tumors and normal tissue, including the known oncogenic miRNAs miR-182, miR-503, and mir-17~92 cluster. These DE miRNAs were correlated with the relative abundances of several bacterial taxa, including Firmicutes, Bacteroidetes, and Proteobacteria. Bacteria correlated with DE miRNAs were enriched with distinct predicted metabolic categories. Additionally, we found that miRNAs that correlated with CRC-associated bacteria are predicted to regulate targets that are relevant for host-microbiome interactions and highlight a possible role for miRNA-driven glycan production in the recruitment of pathogenic microbial taxa. Our work characterized a global relationship between microbial community composition and miRNA expression in human CRC tissues. IMPORTANCE Recent studies have found an association between colorectal cancer (CRC) and the gut microbiota. One potential mechanism by which the microbiota can influence host physiology is through affecting gene expression in host cells. MicroRNAs (miRNAs) are small noncoding RNA molecules that can regulate gene expression and have important roles in cancer development. Here, we investigated the link between the gut microbiota and the expression of miRNA in CRC. We found that dozens of miRNAs are differentially regulated in CRC tumors and adjacent normal colon and that these miRNAs are correlated with the abundance of microbes in the tumor microenvironment. Moreover, we found that microbes that have been previously associated with CRC are correlated with miRNAs that regulate genes related to interactions with microbes. Notably, these miRNAs likely regulate glycan production, which is important for the recruitment of pathogenic microbial taxa to the tumor. This work provides a first systems-level map of the association between microbes and host miRNAs in the context of CRC and provides targets for further experimental validation and potential interventions.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-182"}
{"PMID":29262657,"Year":2017,"Title":"hsa-miR-29c-3p regulates biological function of colorectal cancer by targeting SPARC.","Abstract":"Colorectal cancer (CRC) is the most common type of behavioral cancers, miRNAs play a critical role in cancer development and progression. In the present study, we downloaded the original data from Gene Expression Omnibus (GEO) and conduct data analysis. has-mir-29c-3p mimic, inhibitor, negative control or si-SPARC (secreted protein acidic, rich in cysteine) were transfected into HCT116 cells, respectively. Quantitative real time PCR (qRT-PCR) was used to measure has-mir-29c-3p and SPARC mRNA expressions, western blot was used to detect ACAA1 (acetyl-CoA acyltransferase 1), ACOX1 (acyl-CoA oxidase 1), COL1A1(collagen, type I, alpha-1), COL1A2 (collagen, type I, alpha-2), COL4A1 (collagen, type IV, alpha-1), COL5A2 (collagen, type V, alpha-2), COL12A1 (collagen, type XII, alpha-1), CPT2 (carnitine palmitoyltransferase 2), ETHE1 (persulfide dioxygenase), HMGCS2 (3-hydroxy-3-methylglutaryl-CoA synthase 2), SPARC, SQRDL (sulfide quinone oxidoreductase), and TST (thiosulfate sulfurtransferase) protein expression. CCK-8 and wound healing assay were employed to verify cell proliferation and migration. The luciferase reporter assay data made sure the target correlation of has-mir-29c-3p and SPARC. Firstly, we found that the expression of has-mir-29c-3p was lower in CRC tissues than in their paired corresponding non-cancerous tissues and there was significant inversed correlation between has-mir-29c-3p and SPARC. Overexpression of has-mir-29c-3p reduced cell proliferation and migration. SPARC was identified as a direct target of has-mir-29c-3p, whose silencing reduced cell proliferation and migration. These data showed that has-mir-29c-3p regulates CRC cell functions through regulating SPARC expression. Taken together, has-mir-29c-3p may function as an oncogenic miRNA targeting SPARC, targeted modulation of has-mir-29c-3p expression may became a potential strategy for the treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":23817697,"Year":2013,"Title":"Differential expression of microRNAs in plasma of patients with laryngeal squamous cell carcinoma: potential early-detection markers for laryngeal squamous cell carcinoma.","Abstract":"PURPOSE: Altered microRNA (miRNA) expression has been found in many cancers, including lung, breast, prostate, bladder and colorectal cancer. Many recent studies have demonstrated that aberrant plasma miRNAs were also found in various types of cancers. However, the alteration in plasma miRNA expressions in laryngeal squamous cell carcinoma (LSCC) remains unclear. The present study aimed to investigate the alterations in plasma miRNAs in LSCC. METHODS: In the present study, the expression profiles of 738 miRNAs in plasma from 20 patients and 44 healthy subjects were evaluated using high-throughput real-time quantitative polymerase chain reaction. RESULTS: Our results demonstrated that expression levels of 17 miRNAs were significantly upregulated in patients with LSCCs when compared to control group (p < 0.05). Expression levels of nine miRNAs were found significantly downregulated in LSCC patients (p < 0.05). In addition, 17 miRNAs were expressed only in LSCC group, and five of these miRNAs (miR-331-3p, 603, 1303, 660-5p and 212-3p) are LSCC specific and never seen before in plasma of any human subject. CONCLUSION: In conclusion, our study suggests that detecting these LSCC-specific miRNAs in plasma might serve as novel noninvasive biomarkers for LSCC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-212"}
{"PMID":29518480,"Year":2018,"Title":"Longitudinal monitoring reveals dynamic changes in circulating tumor cells (CTCs) and CTC-associated miRNAs in response to chemotherapy in metastatic colorectal cancer patients.","Abstract":"We evaluated the changes in CTC count and CTC-associated miRNAs during the course of chemotherapy in patients with metastatic colorectal cancer. Blood samples were collected from 9 metastatic colorectal cancer patients prior to chemotherapy and at every other chemotherapy session during the course of treatment. CTCs were isolated and enumerated using a size-exclusion method (CellSievo, Singapore). CTC-associated miRNAs were isolated using a paper-based, partitioning method, and analyzed using reverse transcription quantitative real-time PCR (MiRXES, Singapore). CTC count trends generally correlated with disease progression defined by radiological measurements and trends in carcinoembryonic antigen (CEA) levels; hence CTC counts may be useful in cases where CEA is not elevated. CTC-associated miRNAs identified were miR-15b, miR-16, miR-19a, miR-21, miR-25, miR-30d, miR-126, miR-185, miR-221, miR-222, and miR-324-5p. The expression of CTC-associated miRNAs did not appear to correlate with CTC count and exhibited inter-individual heterogeneity. This pilot study suggests that analysis of CTC changes during the course of treatment may be useful in monitoring response to therapy in metastatic colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-16"}
{"PMID":20585341,"Year":2011,"Title":"Role of primary miRNA polymorphic variants in metastatic colon cancer patients treated with 5-fluorouracil and irinotecan.","Abstract":"MicroRNAs are non-coding RNAs that can block mRNA translation and influence mRNA stability. Recent evidence indicates that miRNA variations can affect drug resistance, efficacy, and metabolism, opening new avenues of pharmacogenomics research. We investigated associations between polymorphisms in both miRNA-containing genomic regions (primary and precursor miRNA) and in genes related to miRNA biogenesis with clinical outcome in metastatic colorectal cancer (mCRC) patients treated with 5-fluorouracil and irinotecan (CPT-11). Eighteen single-nucleotide polymorphisms (SNPs) were analyzed in 61 patients. A significant association with tumor response and time to progression (TTP) was found for SNP rs7372209 in pri-miR26a-1 (P=0.041 and P=0.017, respectively). The genotypes CC and CT were favorable when compared with the TT variant genotype. In addition, SNP rs1834306, located in the pri-miR-100 gene, significantly correlated with a longer TTP (P=0.04). In the miRNA-biogenesis pathway, a trend was identified between SNP rs11077 in the exportin-5 gene and disease control rate (P=0.076). This study is the first to suggest a relationship between treatment outcome and SNPs in the miRNA-biogenesis machinery, in both primary and precursor miRNAs. Our results suggest that miRNA polymorphic variants might be useful predictors of clinical outcome in mCRC patients treated with 5-fluorouracil and CPT-11 combination.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-26"}
{"PMID":23243217,"Year":2013,"Title":"Detection of miR-34a promoter methylation in combination with elevated expression of c-Met and beta-catenin predicts distant metastasis of colon cancer.","Abstract":"PURPOSE: Here, we determined whether epigenetic inactivation of miR-34a and miR-34b/c genes may serve as a prognostic marker for distant metastases in colon cancer. EXPERIMENTAL DESIGN: Using a case-control study design of 94 primary colon cancer samples with and without liver metastases, we determined CpG methylation frequencies of miR-34a and miR-34b/c promoters, expression of miR-34a, and its targets c-Met, Snail, and beta-catenin and their prognostic value. RESULTS: miR-34a methylation was detected in 45.1% (n = 42 of 93) of the samples and strongly associated with metastases to the liver (P = 0.003) and lymph nodes (P = 0.006). miR-34b/c methylation was detected in 91.9% of the samples (n = 79/86). A significant inverse correlation between miR-34a methylation and expression of mature miR-34a (P = 0.018) was detected. Decreased miR-34a expression was associated with upregulation of c-Met, Snail, and beta-catenin protein levels (P = 0.031, 0.132, and 0.004), which were associated with distant metastases (P = 0.001, 0.017, and 0.005). In a confounder-adjusted multivariate regression model miR-34a methylation, high c-Met and beta-catenin levels provided the most significant prognostic information about metastases to the liver (P = 0.014, 0.031, and 0.058) and matched pairs showed a higher prevalence of these risk factors in the samples with distant spread (P = 0.029). Finally, we obtained statistical evidence indicating that the simultaneous detection of these three markers has the highest prognostic value. CONCLUSIONS: Silencing of miR-34a and upregulation of c-Met, Snail, and beta-catenin expression is associated with liver metastases of colon cancer. Detection of miR-34a silencing in resected primary colon cancer may be of prognostic value, especially in combination with detection of c-Met and beta-catenin expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":26556872,"Year":2015,"Title":"Radiation and SN38 treatments modulate the expression of microRNAs, cytokines and chemokines in colon cancer cells in a p53-directed manner.","Abstract":"Aberrant expression of miRNAs, cytokines and chemokines are involved in pathogenesis of colon cancer. However, the expression of p53 mediated miRNAs, cyto- and chemokines after radiation and SN38 treatment in colon cancer remains elusive. Here, human colon cancer cells, HCT116 with wild-type, heterozygous and a functionally null p53, were treated by radiation and SN38. The expression of 384 miRNAs was determined by using the TaqMan(R) miRNA array, and the expression of cyto- and chemokines was analyzed by Meso-Scale-Discovery instrument. Up- or down-regulations of miRNAs after radiation and SN38 treatments were largely dependent on p53 status of the cells. Cytokines, IL-6, TNF-alpha, IL-1beta, Il-4, IL-10, VEGF, and chemokines, IL-8, MIP-1alpha were increased, and IFN-gamma expression was decreased after radiation, whereas, IL-6, IFN-gamma, TNF-alpha, IL-1beta, Il-4, IL-10, IL-8 were decreased, and VEGF and MIP-1alpha were increased after SN38 treatment. Bioinformatic analysis pointed out that the highly up-regulated miRNAs, let-7f-5p, miR-455-3p, miR-98, miR-155-5p and the down-regulated miRNAs, miR-1, miR-127-5p, miR-142-5p, miR-202-5p were associated with colon cancer pathways and correlated with cyto- or chemokine expression. These miRNAs have the potential for use in colon cancer therapy as they are related to p53, pro- or anti-inflammatory cyto- or chemokines after the radiation and SN38 treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":22811001,"Year":2012,"Title":"Circulating miRNA is a novel marker for head and neck squamous cell carcinoma.","Abstract":"The aim of the study is to investigate the alteration of plasma miRNA in head and neck squamous cell carcinoma (HNSCC). Altered microRNAs (miRNAs) expression has been found in many cancers, including lung cancer, breast cancer, prostate cancer, bladder cancer and colorectal cancer. Many recent studies have demonstrated that aberrant plasma miRNAs were also found in various types of cancers. However the alteration of plasma expression in HNSCC remains unclear. In this present study, the expression profiles of ten miRNAs, let-7a, miR-21, miR26b, miR-34c, miR-99a, miR-133a, miR-137, miR-184, miR-194a, and miR-375, in plasma from 50 patients and 36 healthy subjects were evaluated using real-time quantitative polymerase chain reaction (PCR). Our results demonstrated that the expression level of miR-21 was significantly up-regulated in plasma samples obtained from HNSCC patients (p < 0.01) than those from healthy subjects, which were in consistent with our finding in HNSCC tissues. A 7.7-fold increase of miR-21 in cancerous parts when compared to their non-cancerous counterparts (p < 0.0001) was observed in HNSCC tissues. In addition, the expression levels of miR-21 and miR-26b were both reduced in post-operative HNSCC patients with good prognosis. In contrast, the concentration of plasma miR-21 and miR-26b stayed high after tumor removal in the expired cases. Our study suggests that detecting circulating miR-21 and miR-26b pre- and post-operatively might provide a novel tumor marker for HNSCC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-133"}
{"PMID":25592646,"Year":2015,"Title":"Intra-tumoural vessel area estimated by expression of epidermal growth factor-like domain 7 and microRNA-126 in primary tumours and metastases of patients with colorectal cancer: a descriptive study.","Abstract":"BACKGROUND: Understanding the biological properties of potential drug targets are important. This is especially true for anti-angiogenic therapies in the search for potential biomarkers. The aim of the present descriptive study was to analyse the intra-tumoural expressions of epidermal growth factor-like domain 7 (EGFL7) and microRNA-126 (miRNA-126) in primary tumours from patients with stage II-IV colorectal cancer (CRC) and in paired samples of primary tumours, regional lymph node metastases and distant metastases. METHODS: A total of 126 patients were included. Analyses were performed on resections of primary tumours, regional lymph node metastases, and large needle biopsies from distant metastases. EGFL7 was analysed by immunohistochemistry (IHC) and miRNA-126 by in situ hybridization (ISH). Both biomarkers were quantified by image guided analyses to determine the relative fraction estimates of vessel areas (VA). RESULTS: The intra-tumoural EGFL7 VA was significantly higher in primary tumours from patients with recurrent disease than in patients without relapse in both stage II and III, p = 0.019 and p = 0.001, respectively. The EGFL7 VA was significantly higher and the miRNA-126 VA significantly lower in regional lymph node metastases compared to primary tumours, p = 0.01 and p < 10(-6), respectively. Furthermore, the miRNA-126 VA in liver metastases was significantly lower than in the primary tumours, p = 0.02. CONCLUSION: The intra-tumoural expression of EGFL7 in early stages of CRC may influence the risk of post-surgical recurrence. Differential expression of miRNA-126 seems more pronounced in disseminated disease, which supports its role as a regulator in the metastatic process.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-126"}
{"PMID":28207045,"Year":2017,"Title":"Remodelling of microRNAs in colorectal cancer by hypoxia alters metabolism profiles and 5-fluorouracil resistance.","Abstract":"Solid tumours have oxygen gradients and areas of near and almost total anoxia. Hypoxia reduces sensitivity to 5-fluorouracil (5-FU)-chemotherapy for colorectal cancer (CRC). MicroRNAs (miRNAs) are hypoxia sensors and were altered consistently in six CRC cell lines (colon cancer: DLD-1, HCT116 and HT29; rectal cancer: HT55, SW837 and VACO4S) maintained in hypoxia (1 and 0.2% oxygen) compared with normoxia (20.9%). CRC cell lines also showed altered amino acid metabolism in hypoxia and hypoxia-responsive miRNAs were predicted to target genes in four metabolism pathways: beta-alanine; valine, leucine, iso-leucine; aminoacyl-tRNA; and alanine, aspartate, glutamate. MiR-210 was increased in hypoxic areas of CRC tissues and hypoxia-responsive miR-21 and miR-30d, but not miR-210, were significantly increased in 5-FU resistant CRCs. Treatment with miR-21 and miR-30d antagonists sensitized hypoxic CRC cells to 5-FU. Our data highlight the complexity and tumour heterogeneity caused by hypoxia. MiR-210 as a hypoxic biomarker, and the targeting of miR-21 and miR-30d and/or the amino acid metabolism pathways may offer translational opportunities.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-30"}
{"PMID":25484364,"Year":2015,"Title":"An evaluation and replication of miRNAs with disease stage and colorectal cancer-specific mortality.","Abstract":"MicroRNAs (miRNAs) have been implicated in colorectal cancer (CRC) development and associated with prognostic indicators such as disease stage and survival. Prognostic associations are often based on few individuals and imprecise. In this study, we utilize population-based data from 1,141 CRC cases to replicate previously reported associations between 121 miRNAs and disease stage and survival. The Agilent Human miRNA Microarray V19.0 was used to generate miRNA data following a stringent quality control protocol. Assessment of survival was done using Cox Proportional Hazard models adjusting for age, disease stage and tumor molecular phenotype. Five miRNAs were associated with more advanced disease stage; hsa-miR-145-5p and hsa-miR-31-5p showed increased expression with more advanced tumor stage, while hsa-miR-200b-3p, hsa-miR-215 and hsa-miR-451a had decreased expression with more advanced tumors. Thirteen miRNAs were associated with CRC mortality among individuals diagnosed with colon cancer while 14 were associated with CRC mortality after a diagnosis with rectal cancer. Strongest associations were observed for those miRNAs that were expressed in a small subset of tumors. Most notable associations were for hsa-miR-145-3p [hazard ratio (HR) 2.94, 95% confidence interval (CI) 1.54, 5.61], and hsa-miR-9-3p (HR 10.28, 95% CI 1.31, 80.84) with colon cancer and hsa-miR-335-5p (HR 0.17, 95% CI 0.05, 0.54) for rectal cancer. hsa-miR-374a-5p, hsa-miR-570-3p and hsa-miR-18a-5p significantly reduced the hazard of dying for all cases, regardless of tumor site. Our findings illustrate the need for a large sample to evaluate the association of miRNAs with survival and disease stage in order to determine associations by tumor site.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-570"}
{"PMID":22710713,"Year":2013,"Title":"MicroRNA-497 targets insulin-like growth factor 1 receptor and has a tumour suppressive role in human colorectal cancer.","Abstract":"Past studies have shown that amplified insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1-R) signalling has an important role in colorectal cancer (CRC) development, progression and resistance to treatment. In this report, we demonstrate that downregulation of microRNA-497 (miR-497) as a result of DNA copy number reduction is involved in upregulation of IGF1-R in CRC cells. MiR-497 and miR-195 of the miR-15/16/195/424/497 family that share the same 3' untranslated region (3'UTR) binding seed sequence and are predicted to target IGF1-R were concurrently downregulated in the majority of CRC tissues relative to paired adjacent normal mucosa. However, only overexpression of miR-497 led to suppression of the IGF1-R 3'UTR activity and downregulation of the endogenous IGF1-R protein in CRC cells. This was associated with inhibition of cell survival, proliferation and invasion, and increased sensitivity to apoptosis induced by various stimuli including the chemotherapeutic drugs cisplatin and 5-fluorouracil, and the death ligand tumour necrosis factor-related apoptosis-inducing ligand. The biological effect of miR-497 on CRC cells was largely mediated by inhibition of phosphatidylinositol 3-kinase/Akt signalling, as overexpression of an active form of Akt reversed its impact on cell survival and proliferation, recapitulating the effect of overexpression of IGF1-R. Downregulation of miR-497 and miR-195 appeared to associate with copy number loss of a segment of chromosome 17p13.1, where these miRs are located at proximity. Similarly to miR-195, the members of the same miR family, miR-424 that was upregulated, and miR-15a, miR-15b and miR-16 that were unaltered in expression in CRC tissues compared with paired adjacent normal mucosa, did not appear to have a role in regulating the expression of IGF1-R. Taken together, these results identify downregulation of miR-497 as an important mechanism of upregulation of IGF1-R in CRC cells that contributes to malignancy of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-424"}
{"PMID":26452129,"Year":2015,"Title":"MicroRNA-506 suppresses tumor proliferation and metastasis in colon cancer by directly targeting the oncogene EZH2.","Abstract":"Increasing evidence reveals that aberrant expression of microRNA contributes to the development and progression of colon cancer, but the roles of microRNA-506 (miR-506) in colon cancer remain elusive. Here, we demonstrated that miR-506 was down-regulated in colon cancer tissue and cells and that miR-506 expression was inversely correlated with EZH2 expression, tumor size, lymph node invasion, TNM stage and metastasis. A high level of miR-506 identified patients with a favorable prognosis. In vitro and in vivo experiments confirmed that miR-506 inhibits the proliferation and metastasis of colon cancer, and a luciferase reporter assay confirmed that EZH2 is a direct and functional target of miR-506 via the 3'UTR of EZH2. The restoration of EZH2 expression partially reversed the proliferation and invasion of miR-506-overexpressing colon cancer cells. Moreover, we confirmed that the miR-506-EZH2 axis inhibits proliferation and metastasis by activating/suppressing specific downstream tumor-associated genes and the Wnt/beta-catenin signaling pathway. Taking together, our study sheds light on the role of miR-506 as a suppressor for tumor growth and metastasis and raises the intriguing possibility that miR-506 may serve as a new potential marker for monitoring and treating colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-506"}
{"PMID":21826996,"Year":2011,"Title":"[Differential expression of colon cancer microRNA in microarry study].","Abstract":"OBJECTIVE: To investigate the miRNA expression difference between colon cancer and normal colonic mucosa. METHODS: Twelve (12) pairs of colorectal cancer tissue and normal colonic mucosa were collected, total RNA was extracted and purified. After fluorescent tags being added, hybridization was carried out on miRNA microarray chip (Affymetrix company). SAM analysis was performed to find out the significant expression difference, then the difference was verified by RT-PCR, finally target gene analysis software was utilized to predict the miRNA function. RESULTS: The up-regulated miRNAs in colon cancer included has-miR-182, has-miR-17, hasmiR-106a, has-miR-93, has-miR-200c, has-miR-92a, has-let-7a, has-miR-20a (FDR value < 5%), while the downregulated miRNAs were has-miR-l195, has-miR-143, has-miR-145 (FDR value < 5%). CONCLUSION: There is significant difference of miRNA expression between colon caner and normal colonic mucosa.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":25232258,"Year":2014,"Title":"Downregulation of miR-193a-5p correlates with lymph node metastasis and poor prognosis in colorectal cancer.","Abstract":"AIM: To investigate the correlation of miR-193a-5p with lymph node metastasis and postoperative survival of colorectal cancer (CRC) patients. METHODS: A total of 304 formalin-fixed, paraffin-embedded specimens (69 paired cancer and normal tissues, 55 primary tumors of stage III CRC and matched lymph nodes, and 56 primary tumors of stage II CRC) were included in this study. The relative expression levels of miR-193a-5p in the normal mucosa, primary cancer, and metastatic lymph node lesions were measured by quantitative real-time reverse transcriptase polymerase chain reaction. We evaluated the association of its expression with colorectal cancer lymph node metastasis, clinicopathological factors, and patient survival. RESULTS: The relative expression level of miR-193a-5p was significantly lower in CRC tissues than in the normal mucosa (P = 0.0060). The expression levels of miR-193a-5p were lower in primary CRC tissues with lymph node metastases than in those without metastases (P = 0.0006), and decreased expression of miR-193a-5p correlated with advanced lymph node metastatic stage (P = 0.0007). Kaplan-Meier analysis showed that patients with low miR-193a-5p expression had decreased disease-free survival (DFS) (P = 0.0026) and poor overall survival (OS) (P = 0.0003). Interestingly, for the group of patients with lymph node metastases, miR-193a-5p expression was also related to survival. Patients with low miR-193a-5p expression had decreased DFS (P = 0.0262) and poor OS (P = 0.0230). Moreover, multivariate analysis indicated that downregulation of miR-193a-5p was an independent predictor of poor OS. CONCLUSION: Downregulation of miR-193a-5p correlates with lymph node metastasis and poor survival of CRC. miR-193a-5p may be a useful biomarker for CRC diagnosis, metastasis and prognosis prediction.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-193"}
{"PMID":28086904,"Year":2017,"Title":"The lncRNA CRNDE promotes colorectal cancer cell proliferation and chemoresistance via miR-181a-5p-mediated regulation of Wnt/beta-catenin signaling.","Abstract":"BACKGROUND: With more than 600,000 mortalities each year, colorectal cancer (CRC) is the third most commonly diagnosed type of cancer worldwide. Recently, mechanisms involving noncoding RNAs have been implicated in the development of CRC. METHODS: We examined expression levels of lncRNA CRNDE and miR-181a-5p in 64 cases of CRC tissues and cell lines by qRT-PCR. Gain-of-function and loss-of-function assays were performed to examine the effect of CRNDE and miR-181a-5p on proliferation and chemoresistance of CRC cells. Using fluorescence reporter and western blot assays, we also explored the possible mechanisms of CRNDE in CRC cells. RESULTS: In this study, we found that the expression levels of the CRNDE were upregulated in CRC clinical tissue samples. We identified microRNA miR-181a-5p as an inhibitory target of CRNDE. Both CRNDE knockdown and miR-181a-5p overexpression in CRC cell lines led to inhibited cell proliferation and reduced chemoresistance. We also determined that beta-catenin and TCF4 were inhibitory targets of miR-181a-5p, and that Wnt/beta-catenin signaling was inhibited by both CRNDE knockdown and miR-181a-5p overexpression. Significantly, we found that the repression of cell proliferation, the reduction of chemoresistance, and the inhibition of Wnt/beta-catenin signaling induced by CRNDE knockdown would require the increased expression of miR-181a-5p. CONCLUSIONS: Our study demonstrated that the lncRNA CRNDE could regulate the progression and chemoresistance of CRC via modulating the expression levels of miR-181a-5p and the activity of Wnt/beta-catenin signaling.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-181"}
{"PMID":27022275,"Year":2016,"Title":"Screening miRNAs for early diagnosis of colorectal cancer by small RNA deep sequencing and evaluation in a Chinese patient population.","Abstract":"PURPOSE: This study aims to screen microRNAs (miRNAs), for an early diagnosis of colorectal cancer, by deep sequencing and evaluation of total miRNAs using clinical samples from a Chinese patient population. METHODS: Total small RNAs from normal colonic mucosa, colonic adenomas, and colorectal cancer tissues were prepared for miRNA analysis by deep sequencing. The sequencing data were then analyzed by bioinformatics for candidate diagnostic miRNAs, which were further validated for their up- or downregulation status. RESULTS: Comparison of cancer tissues with normal mucosa identified 99 upregulated and 90 downregulated miRNAs. Comparison of adenomas and normal mucosa found 114 upregulated and 107 downregulated miRNAs. Comparison of cancer and adenoma tissues found 70 upregulated and 27 downregulated miRNAs. Selected up- and downregulated miRNAs were validated for their expressions in 12 cases of patients with cancer and polyps. Specifically, for the upregulated miRNAs, miR-18a-5p and miR-21-3p were significantly upregulated in adenomas and cancer tissues, compared with the normal mucosa; miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, and miR-200c-3p were significantly upregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissues when compared with the normal mucosa. miR-183-5p and miR-96-5p were significantly upregulated in adenoma tissues when compared with normal mucosa, but these differences were not significant in cancer tissues when compared to normal mucosa. For the downregulated miRNAs, miR-133a-3p was significantly downregulated in both adenoma and cancer tissues when compared to normal mucosa; miR-204-5p, miR-125b-5p, miR-139-5p, miR-100-5p, and miR-30a-5p were significantly downregulated in cancer tissues compared to the normal mucosa, but their differential expression was not significant in adenoma tissue compared to normal mucosa. CONCLUSION: The findings of this study show that a number of miRNAs might be important in the diagnosis and prognosis of colorectal cancer in Chinese patients using the method of small RNA deep sequencing. Upregulation of miR-18a-5p and miR-21-3p or downregulation of miR-133a-3p in adenoma and cancer tissues may serve as an index for early screening of colorectal cancer. Other miRNAs, such as miR-135b-5p, miR-17-5p, miR-182-5p, miR-200a-5p, miR-200c-3p, miR-183-5p, and miR-96-5p, which were either up- or downregulated, in cancer tissues, but not in adenoma tissues, have limited significance in early diagnosis. Further study is needed to determine a screening index with diagnostic value.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-139"}
{"PMID":26208586,"Year":2016,"Title":"Associations of Polymorphisms in mir-196a2, mir-146a and mir-149 with Colorectal Cancer Risk: A Meta-Analysis.","Abstract":"MicroRNAs (miRNAs) are non-coding RNAs which act as tumor suppressors or oncogenes. And single nucleotide polymorphism (SNP) in miRNA regions is one type of genetic variations in human genome. Various studies have investigated the associations of miRNAs SNP and kinds of cancers. In this article, we searched eligible studies to explore the relationships between mir-196a2 /mir-146a /mir-149 polymorphisms and colorectal cancer (CRC). A literature search of PubMed, Web of Science and ScienceDirect was conducted to identify all relevant studies. Three genetic models with pooled ratio and 95% confidence interval were used to evaluate the associations. We found that mir-196a2 polymorphism was significantly associated with CRC in Asian group (additive model: OR = 1.197, 95%CI 1.084 ~ 1.32, P < 0.001; dominant model: OR = 1.247, 95%CI 1.065 ~ 1.46, P = 0.006; recessive model: OR = 1.298, 95%CI 1.101 ~ 1.531, P = 0.002). And no associations were observed between SNPs of mir-146a, mir-149 and CRC in three genetic models. We also found CRC risk was not associated with mir-146a and mir-149 polymorphisms in population subgroup analysis. The current meta-analysis suggests that mir-196a2 polymorphism is associated with CRC, especially in Asian group. While, no associations have been found between mir-146a /mir-149 polymorphisms and CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":29511442,"Year":2018,"Title":"SRPX2 regulates colon cancer cell metabolism by miR-192/215 via PI3K-Akt.","Abstract":"Colon cancer is one of common cancer in the world and glycolysis is one of the major problems in colon cancer therapy. MicroRNAs (miRNAs) involve in colon cancer progression. Sushi repeat-containing protein X-linked 2 (SRPX2) is associated with poor prognosis in some cancer patients, however, the role of SRPX2 including glycolytic metabolism regulated by miRNAs is unclear in colon cancer. So, the purpose of the present study is to elucidate the underlying mechanism in colon cancer metabolism mediated by SRPX2. Our results revealed that miR-192-5p (miR-192) and miR-215-5p (miR-215) inhibited glycolysis by regulating SRPX2 expression in colon cancer cells. We also found that miR-192 and miR-215 were both regulated by PI3K-Akt. Our results indicate that SRPX2 facilitates colon cancer cell glycolysis by miR-192 and miR-215, which are down-regulated by PI3K-Akt.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-192"}
{"PMID":23456911,"Year":2015,"Title":"A plasma microRNA panel for early detection of colorectal cancer.","Abstract":"Colonoscopy remains the standard screening method for detecting colorectal cancer (CRC) at an early stage. However, many people avoid having a colonoscopy because of the fear for its potential complications. Our study aimed to identify plasma microRNAs for preliminarily screening CRC in general population, so that some unnecessary colonoscopies can be avoided. We investigated plasma microRNA expression in three independent cohorts including the discovery (n = 80), training (n = 112), and validation (n = 49) phases recruited at two medical centers. Microarrays were used for screening 723 microRNAs in 80 plasma samples to identify candidate microRNAs. Quantitative reverse-transcriptase PCR was performed on the 161 training and validation plasma samples to evaluate the candidate microRNAs discovered from microarrays. A logistic regression model was constructed based on the training cohort and then verified by using the validation dataset. Area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic accuracy. We identified a panel of miR-409-3p, miR-7, and miR-93 that yielded high diagnostic accuracy in discriminating CRC from healthy group (AUC: 0.866 and 0.897 for training and validation dataset, respectively). Moreover, the diagnostic performance of the microRNA panel persisted in nonmetastasis CRC stages (Dukes' A-B, AUC: 0.809 and 0.892 for training and validation dataset, respectively) and in metastasis CRC stages (Dukes' C-D, AUC: 0.917 and 0.865 for training and validation dataset, respectively). In conclusion, our study reveals a plasma microRNA panel that has potential clinical value in early CRC detection and would play a critical role on preliminarily screening CRC in general population.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-93"}
{"PMID":25472670,"Year":2014,"Title":"Suitability of circulating miRNAs as potential prognostic markers in colorectal cancer.","Abstract":"miRNAs are crucial in cellular processes and have been shown to be abnormally expressed in cancer tissue and the circulation. Circulating miRNAs may serve as a novel class of minimally invasive biomarkers for prognosis. Within a first methodologic study, we evaluated the miRNA profile kinetics in the plasma of patients with colorectal cancer after surgical tumor removal to identify potential suitability as prognostic biomarkers. This pilot study is based on the ColoCare Study, a cohort study of newly diagnosed patients with stage I-IV colorectal cancer. Colorectal cancer pre- and postsurgical blood (2-7 days after surgery) and 6 months follow-up blood from 35 patients were examined and candidate miRNAs were investigated in the plasma. miRNA levels were measured by two-step qRT-PCR. Statistical analysis was performed using log-transformed normalized CT values using SAS 9.3. Comparing pre- and postsurgical miRNA levels revealed a statistically significant decrease of nine circulating miRNAs after surgery (miR92a, miR18a, miR320a, miR106a, miR16-2, miR20a, miR223, miR17, and miR143). Analyses of plasma levels over all three time points demonstrated a statistically significant decrease from presurgery to postsurgery and re-increase from postsurgery to the six months follow-up time point of four circulating miRNAs (miR92a, miR320a, miR106a, and miR18a). We were able to show for the first time that in plasma miRNA profiles change within days after colorectal cancer surgery. Our results underscore the role of the investigated miRNAs in colorectal cancer and their potential utility as prognostic biomarkers. See all the articles in this CEBP Focus section, \"Biomarkers, Biospecimens, and New Technologies in Molecular Epidemiology.\"","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-320"}
{"PMID":27824903,"Year":2016,"Title":"miR-146a Polymorphism (rs2910164) Predicts Colorectal Cancer Patients' Susceptibility to Liver Metastasis.","Abstract":"miR-146a plays important roles in cancer as it directly targets NUMB, an inhibitor of Notch signaling. miR-146a is reportedly regulated by a G>C polymorphism (SNP; rs2910164). This polymorphism affects various cancers, including colorectal cancer (CRC). However, the clinical significance of miR-146a polymorphism in CRC remains unclear. A total of 59 patients with CRC were divided into 2 groups: a CC/CG genotype (n = 32) and a GG genotype (n = 27), based on the miR-146a polymorphism. cDNA microarray analysis was performed using 59 clinical samples. Significantly enriched gene sets in each genotype were extracted using GSEA. We also investigated the association between miR-146a polymorphism and miR-146a, NUMB expression or migratory response in CRC cell lines. The CC/CG genotype was associated with significantly more synchronous liver metastasis (p = 0.007). A heat map of the two genotypes showed that the expression profiles were clearly stratified. GSEA indicated that Notch signaling and JAK/STAT3 signaling were significantly associated with the CC/CG genotype (p = 0.004 and p = 0.023, respectively). CRC cell lines with the pre-miR-146a/C revealed significantly higher miR-146a expression (p = 0.034) and higher NUMB expression and chemotactic activity. In CRC, miR-146a polymorphism is involved in liver metastasis. Identification of this polymorphism could be useful to identify patients with a high risk of liver metastasis in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-146"}
{"PMID":24949825,"Year":2014,"Title":"Integrating analysis reveals microRNA-mediated pathway crosstalk among Crohn's disease, ulcerative colitis and colorectal cancer.","Abstract":"Inflammatory bowel disease (IBD), which can increase the risk of colorectal cancer (CRC), includes two primary subtypes, ulcerative colitis (UC) and Crohn's disease (CD). Although several individual genes involved in inflammation or cancer characterization have been identified, it is still difficult to elucidate functional relationship details between the molecules underlying pathogenesis at the system level. The global effect of miRNAs on genes or their involved functions is also poorly understood. We first integrated genome-wide gene expression profiles and biological pathway information to explore the underlying associations among UC, CD and CRC at the function and gene level. After identifying the pathways regulated by miRNAs, a global map of miRNA-mediated pathway crosstalk shared by the three diseases was further constructed to vertically explain the links of three level alterations. The three types of diseases have close associations with each other at the levels of function, gene and miRNA regulation. Several key biological pathways are involved in the three diseases, related to the immune system and inflammation, metabolism, or cell proliferation and apoptosis etc. Moreover, miRNAs exhibit dominant effects on multiple pathways. It is worth noting that UC shows relatively close associations with CD and CRC at the three levels. Finally, the miRNAs could mediate the crosstalk within or between pathways. For example, hsa-miR-125b, hsa-miR-335 and hsa-miR-155 mediated the crosstalk between three metabolic pathways. The crosstalk within the Toll-like receptor signaling pathway could be mediated by hsa-miR-124, hsa-miR-146a and hsa-mir-221/222. Our results make sense for the prevention and treatment of intestinal-related chronic inflammation or cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-155"}
{"PMID":26312830,"Year":2015,"Title":"Circulating plasma microRNAs as a screening method for detection of colorectal adenomas.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNA molecules. Reduced or increased levels of specific miRNAs are observed in colon and other cancers, supporting their role in carcinogenesis. Detection of colorectal polyps is the cornerstone of the Bowel Cancer Screening Programme in the UK. However, uptake of screening nationally remains under 60%. We aimed to see whether circulating plasma miRNAs can be used to screen for patients with colorectal polyps, adenomas, or both. METHODS: Blood samples were taken from patients from the Bowel Cancer Screening Programme (asymptomatic but faecal occult blood testing [FOBt] positive). Plasma RNA was extracted, target miRNAs (19a, 98, 146b, 186, 191, 222*, 331-5p, 452, 625, 664, 1247) were identified on pooled case miRNA assay cards, and miRNA fraction was quantified by quantitative RT-PCR assay. Results were compared with endoscopy reports and with histology of any polyps identified and removed. Analysis was done with Excel (2011) and SPSS (version 20) software. FINDINGS: 210 patients were included (117 with polyps, 12 with cancer, 81 healthy controls [FOBt positive]). The miRNA panel showed significant differences in expression (on t testing) for patients compared with controls for those with polyps, cancer, or both (miR-19a, p=0.0184; miR-98, p=0.0206; miR-146b, p=0.0029; miR-186, p=0.0006; miR-62,5 p=0.0008), polyps (miR-19a, p=0.0233; miR-98, p=0.0224; miR-146b, p=0.003; miR-186, p=0.0004; miR-625, p=0.001), adenomas (miR-19a, p=0.0339; miR-98, p=0.0266; miR-146b, p=0.0045; miR-186, p=0.0008; miR-625, p=0.0049), multiple adenomas (both sides of colon; miR-146b, p=0.0194; miR-186, p=0.0226; miR-625, p=0.0013), and right-sided adenomas (miR-98, p=0.031; miR-146b, p=0.0076; miR-186, p=0.0041; miR-331-5p, p=0.0142; miR-625, p=0.0049). Receiver operating characteristic analysis showed sensitivity of 60% or more, and specificity of 86% or more for men with polyps, men with adenomas, all patients with haemorrhoids or diverticulosis and polyps, and all patients with haemorrhoids or diverticulosis and adenomas. INTERPRETATION: The target miRNAs that we identified showed significant differences in expression levels for patients with polyps and patients with adenomas from controls. Use of this panel has potential as a screening test. FUNDING: Bowel Disease Research Foundation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-98"}
{"PMID":25315964,"Year":2015,"Title":"MicroRNA classifier and nomogram for metastasis prediction in colon cancer.","Abstract":"BACKGROUND: Colon cancer prognosis and treatment are currently based on a classification system still showing large heterogeneity in clinical outcome, especially in TNM stages II and III. Prognostic biomarkers for metastasis risk are warranted as development of distant recurrent disease mainly accounts for the high lethality rates of colon cancer. miRNAs have been proposed as potential biomarkers for cancer. Furthermore, a verified standard for normalization of the amount of input material in PCR-based relative quantification of miRNA expression is lacking. METHODS: A selection of frozen tumor specimens from two independent patient cohorts with TNM stage II-III microsatellite stable primary adenocarcinomas was used for laser capture microdissection. Next-generation sequencing was performed on small RNAs isolated from colorectal tumors from the Dutch cohort (N = 50). Differential expression analysis, comparing in metastasized and nonmetastasized tumors, identified prognostic miRNAs. Validation was performed on colon tumors from the German cohort (N = 43) using quantitative PCR (qPCR). RESULTS: miR25-3p and miR339-5p were identified and validated as independent prognostic markers and used to construct a multivariate nomogram for metastasis risk prediction. The nomogram showed good probability prediction in validation. In addition, we recommend combination of miR16-5p and miR26a-5p as standard for normalization in qPCR of colon cancer tissue-derived miRNA expression. CONCLUSIONS: In this international study, we identified and validated a miRNA classifier in primary cancers, and propose a nomogram capable of predicting metastasis risk in microsatellite stable TNM stage II-III colon cancer. IMPACT: In conjunction with TNM staging, by means of a nomogram, this miRNA classifier may allow for personalized treatment decisions based on individual tumor characteristics.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-25"}
{"PMID":29573205,"Year":2018,"Title":"Plasma miRNA can detect colorectal cancer, but how early?","Abstract":"Colorectal cancer (CRC) is a major cause of deaths worldwide but has a good prognosis if detected early. The need for efficient, preferable non- or minimally invasive, inexpensive screening tools is therefore critical. We analyzed 12 miRNAs in pre- and postdiagnostic plasma samples to evaluate their potential as CRC screening markers. We used a unique study design with two overlapping cohorts, allowing analysis of pre- and postdiagnostic samples from 58 patients with CRC and matched healthy controls. Plasma concentrations of miR-15b, -16, -18a, -19a, 21, -22, -25, -26a, -29c, -142-5p, -150, and -192 were measured by semi-quantitative real-time PCR. Concentrations of miR-18a, -21, -22, and -25 in plasma from patients with CRC were significantly altered compared to healthy controls. Combined as a multimarker panel, they detected CRC with an AUC of 0.93. Furthermore, levels of these three miRNAs also showed different levels in the prediagnostic case samples close to diagnosis. Only miR-21-levels were elevated several years before diagnosis. Plasma levels of miR-18a, -21, -22, and -25 show promise as screening biomarkers for CRC. However, based on our unique analysis of prediagnostic and postdiagnostic samples from the same patients, we conclude that circulating miRNAs elevated at diagnosis may not automatically be suitable for CRC screening, if the increase occurs too close to clinical diagnosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":30476915,"Year":2018,"Title":"miR-135a Protects Dextran Sodium Sulfate-Induced Inflammation in Human Colorectal Cell Lines by Activating STAT3 Signal.","Abstract":"BACKGROUND/AIMS: miR-135a is reduced in several cancers and has been suggested to mediate immune and inflammatory responses. However, the effect of miR-135a on inflammatory bowel diseases was obscure. This study firstly attempted to investigate the hypothesis that miR-135a alleviates dextran sodium sulfate (DSS)-induced inflammation in colonic cells and potential mechanisms are also studied. METHODS: Caco-2 and HT-29 cells in this study were treated with DSS, miR-135a mimic, and S3I-201, and then CKK-8 assay was used to test cell viability. Expressions of miR-135a, cytokines, and signal transducers and activators of transcription factors (STATs) were determined by RT-PCR. Also, cytokine productions were further tested by using ELISA kits. Activation or inactivation of STAT3 signal was validated by western blotting analysis. RESULTS: The results showed that DSS markedly downregulated miR-135a expression (P< 0.05) and induced inflammatory response in Caco-2 and HT-29 cells evidenced by the up regulations and productions of interleukin-1beta (IL-1beta) and tumor necrosis factor-a (TNF-a) (P< 0.05). Transfection with miR-135a mimic significantly alleviated DSS-induced upregulation and productions of IL-1beta and TNF-a in Caco-2 and HT-29 cells (P< 0.05). STATs were analyzed and miR-135a mimic treatment reversed STAT3 downregulation in DSS-challenged Caco-2 and HT-29 cells compared with the mimic control (P< 0.05). Also, STAT3 phosphorylation was inhibited in DSS-challenged Caco-2 cells and miR-135a mimic activated STAT3 signal (P< 0.05). S3I-201, an inhibitor of STAT3 signal, further used to inactivate STAT3 signal and the results showed that S3I-201 blocked the anti-inflammatory effect of miR-135a mimic on Caco-2 and HT-29 cells evidenced by the lowered expressions and productions of proinflammatory cytokines ((IL-1beta and TNF-a) (P< 0.05). CONCLUSION: Our results indicated that miR-135a alleviated DSS-induced inflammation and activated STAT3 signal in colonic cells. Inhibition of STAT3 reversed the anti-inflammatory function of miR-135a by regulating proinflammatory cytokines. Thus, STAT3 signal might serve, at least in part, as the potential mechanism of miR-135a-mediated anti-inflammatory effect in colonic cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-135"}
{"PMID":26804235,"Year":2016,"Title":"Rs895819 in MIR27A improves the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity.","Abstract":"The objective of this study was to determine whether genotyping of MIR27A polymorphisms rs895819A>G and rs11671784C>T can be used to improve the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity (FP-toxicity). Patients treated previously in a prospective study with fluoropyrimidine-based chemotherapy were genotyped for rs895819 and rs11671784, and DPYD c.2846A>T, c.1679T>G, c.1129-5923C>G and c.1601G>A. The predictive value of MIR27A variants for early-onset grade >/=3 FP-toxicity, alone or in combination with DPYD variants, was tested in multivariable logistic regression models. Random-effects meta-analysis was performed, including previously published data. A total of 1,592 patients were included. Allele frequencies of rs895819 and rs11671784 were 0.331 and 0.020, respectively. In DPYD wild-type patients, MIR27A variants did not affect risk of FP-toxicity (OR 1.3 for >/=1 variant MIR27A allele vs. none, 95% CI: 0.87-1.82, p = 0.228). In contrast, in patients carrying DPYD variants, the presence of >/=1 rs895819 variant allele was associated with increased risk of FP-toxicity (OR 4.9, 95% CI: 1.24-19.7, p = 0.023). Rs11671784 was not associated with FP-toxicity (OR 2.9, 95% CI: 0.47-18.0, p = 0.253). Patients carrying a DPYD variant and rs895819 were at increased risk of FP-toxicity compared to patients wild type for rs895819 and DPYD (OR 2.4, 95% CI: 1.27-4.37, p = 0.007), while patients with a DPYD variant but without a MIR27A variant were not (OR 0.3 95% CI: 0.06-1.17, p = 0.081). In meta-analysis, rs895819 remained significantly associated with FP-toxicity in DPYD variant allele carriers, OR 5.4 (95% CI: 1.83-15.7, p = 0.002). This study demonstrates the clinical validity of combined MIR27A/DPYD screening to identify patients at risk of severe FP-toxicity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-27"}
{"PMID":30588014,"Year":2018,"Title":"microRNA-769 is downregulated in colorectal cancer and inhibits cancer progression by directly targeting cyclin-dependent kinase 1.","Abstract":"Background: In recent years, microRNAs (miRNAs) have been reported to be aberrantly expressed in colorectal cancer (CRC). The deregulation of miRNAs is implicated in the formation and progression of CRC, and participates in the regulation of a wide range of biological behaviors. Considering the crucial role of miRNAs in CRC, miRNAs are thought to have significant promise in the diagnosis and therapy of patients with this malignancy. Material and methods: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to detect miR-769 expression in CRC tissues and cell lines. MTT assay and flow cytometry analysis were used to determine the effects of miR-769 upregulation in CRC cell proliferation and apoptosis, respectively. The influence of miR-769 overexpression in CRC cell migration and invasion was evaluated through migration and invasion assays. Notably, the possible mechanisms underlying the action of miR-769 in CRC cells were explored. Results: In the present study, miR-769 was frequently found to be poorly expressed in CRC tissues and cell lines. Functional assays showed that recovery of miR-769 expression suppressed CRC cell proliferation, migration, and invasion, increased cell apoptosis in vitro, and inhibited tumor growth in vivo. Cyclin-dependent kinase 1 (CDK1) was the direct target of miR-769 in CRC cells. CDK1 was overexpressed in CRC tissue samples and negatively correlated with miR-769 expression. In addition, CDK1 inhibition imitated the tumor suppressor activity of miR-769 in CRC cells, and restoration of CDK1 expression partially abolished the tumor-suppressing roles of miR-769 in malignant CRC cells. Conclusion: The results of this study demonstrated that miR-769 was downregulated in CRC and directly targeted CDK1 to be implicated in the regulation of CRC cell proliferation, apoptosis, migration and invasion. Thus, the miR-769/CDK1 axis might be an effective therapeutic target for treating patients with CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-769"}
{"PMID":23691514,"Year":2013,"Title":"MicroRNA-124 regulates the proliferation of colorectal cancer cells by targeting iASPP.","Abstract":"MicroRNAs are a class of small, noncoding RNAs that function as critical regulators of gene expression by targeting mRNAs for translational repression or degradation. In this study, we demonstrate that expression of microRNA-124 (miR-124) is significantly downregulated in colorectal cancer tissues and cell lines, compared to the matched adjacent tissues. We identified and confirmed inhibitor of apoptosis-stimulating protein of p53 (iASPP) as a novel, direct target of miR-124 using target prediction algorithms and luciferase reporter gene assays. Overexpression of miR-124 suppressed iASPP protein expression, upregulated expression of the downstream signaling molecule nuclear factor-kappa B (NF- kappa B), and attenuated cell viability, proliferation, and colony formation in SW480 and HT-29 colorectal cancer cells in vitro. Forced overexpression of iASPP partly rescued the inhibitory effect of miR-124 on SW480 and HT29 cell proliferation. Taken together, these findings shed light on the role and mechanism of action of miR-124, indicate that the miR-124/iASPP axis can regulate the proliferation of colorectal cancer cells, and suggest that miR-124 may serve as a potential therapeutic target for colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-124"}
{"PMID":28560697,"Year":2017,"Title":"The Cardiotoxic Mechanism of Doxorubicin (DOX) and Pegylated Liposomal DOX in Mice Bearing C-26 Colon Carcinoma: a Study Focused on microRNA Role for Toxicity Assessment of New Formulations.","Abstract":"PURPOSE: MicroRNAs (miRs) are a group of small non-coding RNAs that regulate transcriptional or post-transcriptional gene expression. The aim of the present study was to investigate the role of miR -1, -21 and -145 and their targets in cardiotoxicity-induced by DOX and pegylated liposomal DOX. METHODS: BALB/c mice subjected to subcutaneous injection of C-26 tumor cells. Eight days after tumor inoculation, animals were divided into 6 groups: control, liposome, DOX (6 and 9 mg/kg) and PL-DOX (6 and 9 mg/kg). The formulations were administered one time per week for four weeks. 24 h after the last injection, mice were sacrificed; blood and heart samples were taken. Western blot analysis was done on protein extracts to investigate the expression of cardiac caspase-3, -8, Bax, Bcl2, Programmed cell death 4 (PDCD4) and BCL2/Adenovirus E1B 19 kDa Interacting Protein 3 (BNIP3). The expression levels of miR -1, -21 and -145 were also evaluated by quantitative real-time PCR. RESULTS: Mice treated with both DOX formulations showed a marked inhibition in tumor growth. Western blot analysis indicated that the expression level of cardiac caspase-3, caspase-8, Bax and BNIP3 were up-regulated due to DOX injection (9 mg/kg). Exposure of mice with DOX resulted in a significant increase in cardiac miR-1 and miR-21 expression level. PL-DOX treatment did not change the proteins and miRs expression. CONCLUSION: The results suggest that miR -1, -21 and -145 may involve in cardiotoxicity induced by DOX. Evaluation of miRs signaling pathways might be of potential value for toxicity assessment of new formulations. Graphical Abstract The cardiotoxic mechanism of doxorubicin (DOX) and pegylated liposomal DOX (PL-DOX).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-1"}
{"PMID":19825969,"Year":2009,"Title":"n-3 Polyunsaturated fatty acids modulate carcinogen-directed non-coding microRNA signatures in rat colon.","Abstract":"We have hypothesized that dietary modulation of intestinal non-coding RNA [microRNA (miRNA)] expression may contribute to the chemoprotective effects of nutritional bioactives (fish oil and pectin). To fully understand the effects of these agents on the expression of miRNAs, Sprague-Dawley rats were fed diets containing corn oil or fish oil with pectin or cellulose and injected with azoxymethane (AOM, a colon-specific carcinogen) or saline (control). Real-time polymerase chain reaction using miRNA-specific primers and Taq Man probes was carried out to quantify effects on miRNA expression in colonic mucosa. From 368 mature miRNAs assayed, at an early stage of cancer progression (10 week post AOM injection), let-7d, miR-15b, miR-107, miR-191 and miR-324-5p were significantly (P < 0.05) affected by diet x carcinogen interactions. Overall, fish oil fed animals exhibited the smallest number of differentially expressed miRNAs (AOM versus saline treatment). With respect to the tumor stage (34 week post AOM injection), 46 miRNAs were dysregulated in adenocarcinomas compared with normal mucosa from saline-injected animals. Of the 27 miRNAs expressed at higher (P < 0.05) levels in tumors, miR-34a, 132, 223 and 224 were overexpressed at >10-fold. In contrast, the expression levels of miR-192, 194, 215 and 375 were dramatically reduced (< or = 0.32-fold) in adenocarcinomas. These results demonstrate for the first time the utility of the rat AOM model and the novel role of fish oil in protecting the colon from carcinogen-induced miRNA dysregulation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":30581003,"Year":2019,"Title":"Facilitating colorectal cancer cell metastasis by targeted binding of long non-coding RNA ENSG00000231881 with miR-133b via VEGFC signaling pathway.","Abstract":"BACKGROUND: Colorectal cancer mainly metastasizes through the lymphatic pathways and is associated with a high mortality rate. It is one of the leading causes of cancer-related deaths. In this study, the effects of long non-coding RNA (lncRNA) ENSG00000231881 on the metastasis of colorectal cancer cells were evaluated. METHODS: The expression level of ENSG00000231881 in colorectal cancer tissues was detected with bioinformatics analysis and quantitative polymerase chain reaction (qPCR) assay. Functional colorectal cancer cell models for the overexpression and interference expression of ENSG00000231881 were established. MTT, transwell, tube formation, qPCR, and western blot assays were performed to detect changes in various cellular functions and expression levels of key factors (miR-133b and vascular endothelial growth factor C [VEGFC]) in ENSG00000231881 functional models. Dual luciferase assay was performed to verify the binding relationship between ENSG00000231881 and miR-133b. RESULTS: ENSG00000231881 expression level was substantially higher in colorectal cancer tissues than in paracancerous tissues and correlated with malignancy and prognosis. In colorectal cancer cells, ENSG00000231881 overexpression significantly promoted cell proliferation, metastasis, and tube formation in lymphatic epithelium, decreased miR-133b expression, and increased VEGFC expression. On the contrary, ENSG00000231881 interference expression showed exactly opposite results. ENSG00000231881 could bind to miR-133b and consequently affect the cell functions through the regulation of VEGFC expression via miR-133b. CONCLUSION: ENSG00000231881 binds to miR-133b via competitive endogenous RNA (ceRNA) mechanism and regulates the VEGFC signaling pathway, consequently leading to the metastasis of colorectal cancer cells. Our study provides a theoretical basis for the use of ENSG00000231881 as a therapeutic target for gene-targeted therapy in colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-133"}
{"PMID":27706637,"Year":2016,"Title":"MicroRNA variants and colorectal cancer risk: a meta-analysis.","Abstract":"Colorectal cancer (CRC) is a multi-factorial disease, and genetic background may contribute to its etiology. Single nucleotide polymorphisms (SNPs) in microRNAs (miRNAs) may be used as specific markers of predisposition for CRC diagnosis and prevention. In this review, we summarize and discuss recent publications evaluating the roles of miRNA SNPs in CRC. A meta-analysis was also carried out to assess the association between the five most frequently studied miRNA SNPs and CRC risk. No relationship was established between this disease and the three SNPs rs11614913, rs2910164, and rs3746444 in miR-196a-2, miR-146a, and miR-499, respectively. However, polymorphisms of miR-149 (rs2292832; CT vs TT: odds ratio [OR] = 0.816, 95% confidence interval [CI] = 0.691-0.963; CC+CT vs TT: OR = 0.834, 95%CI = 0.715-0.972) and pre-miR-27a (rs895819; GG vs AA: OR = 1.534, 95%CI = 1.148-2.049; GG+AG vs AA: OR = 1.324, 95%CI = 1.066-1.645) were found to be associated with CRC in our analysis. In conclusion, the SNPs rs2292832 in miR-149 and rs895819 in pre-miR-27a were associated with CRC susceptibility, whereas rs11614913, rs2910164, and rs3746444 in miR-196a-2, miR-146a, and miR-499, respectively, were not. Further studies should be carried out to validate these findings.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":19921579,"Year":2009,"Title":"[Clinicopathological significance of microRNA-21 and miR-125 expression in colorectal cancer].","Abstract":"OBJECTIVE: To investigate the expression of microRNA(miR)-21 and miR-125 in colorectal cancer (CRC) and its relationship with clinicopathological features. METHODS: Quantitative real-time PCR was applied to examine the expression of miR-21 and miR-125 in 100 primary CRC specimens which were diagnosed and operated in West China Hospital between 2006 and 2007, in comparison with the corresponding normal mucosa specimens. The relationship between the expression of miRNAs and clinicopathological features was analyzed. RESULTS: The expression of miR-21 in CRC was up-regulated by 2.3 times compared to normal mucosa (P =0.025), while the expression of miR-125 was down-regulated by 3.3 times in comparison with normal mucosa (P =0.005). Furthermore, the expression of miR-21 was related to TNM stage (P =0.028) and local invasion (P =0.023). On the other hand, no significant relationship was found between the expression of miR-125 and clinicopathological features (P >0.05). CONCLUSION: The over-expression of miR-21 may play a role in the development and progression of CRC, while miR-125 may not be related to the pathogenesis of CRC.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-125"}
{"PMID":25756961,"Year":2015,"Title":"Concurrent Targeting of KRAS and AKT by MiR-4689 Is a Novel Treatment Against Mutant KRAS Colorectal Cancer.","Abstract":"KRAS mutations are a major cause of drug resistance to molecular-targeted therapies. Aberrant epidermal growth factor receptor (EGFR) signaling may cause dysregulation of microRNA (miRNA) and gene regulatory networks, which leads to cancer initiation and progression. To address the functional relevance of miRNAs in mutant KRAS cancers, we transfected exogenous KRAS(G12V) into human embryonic kidney 293 and MRC5 cells with wild-type KRAS and BRAF genes, and we comprehensively profiled the dysregulated miRNAs. The result showed that mature miRNA oligonucleotide (miR)-4689, one of the significantly down-regulated miRNAs in KRAS(G12V) overexpressed cells, was found to exhibit a potent growth-inhibitory and proapoptotic effect both in vitro and in vivo. miR-4689 expression was significantly down-regulated in cancer tissues compared to normal mucosa, and it was particularly decreased in mutant KRAS CRC tissues. miR-4689 directly targets v-ki-ras2 kirsten rat sarcoma viral oncogene homolog (KRAS) and v-akt murine thymoma viral oncogene homolog 1(AKT1), key components of two major branches in EGFR pathway, suggesting KRAS overdrives this signaling pathway through inhibition of miR-4689. Overall, this study provided additional evidence that mutant KRAS functions as a broad regulator of the EGFR signaling cascade by inhibiting miR-4689, which negatively regulates both RAS/mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/AKT pathways. These activities indicated that miR-4689 may be a promising therapeutic agent in mutant KRAS CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-4689"}
{"PMID":26094174,"Year":2015,"Title":"Housekeeping genes for studies of plasma microRNA: A need for more precise standardization.","Abstract":"INTRODUCTION: Plasma microRNAs (miRNAs) are promising biomarkers for many forms of cancer in humans; however, a fundamental concern is the lack of standardization in current data acquisition and reporting. Part of this problem lies in the use of numerous, different housekeeping genes (HKG) for the acquisition of real-time polymerase chain reaction data. This existing practice of using different HKGs generally is accepted, but reproducibility of data for comparison and validation between different laboratories calls for improvement. The need for data reproducibility standardization is crucial. An ideal plasma HKG (1) should be expressed in all samples, (2) have medium-to-high levels of expression, and (3) have consistently measurable levels of expression. METHODS: Total RNA was extracted from 200-muL plasma samples via a modified miRNeasy (QIAGEN) extraction technique with yeast carrier. Total RNA purity was assessed with a Nanodrop 2000 spectrophotometer (Thermo Scientific). The cycle threshold (Ct) was fixed at 0.03 for all samples. We investigated 10 potential HKGs based both on reports in the literature and our previous data. The potential HKGs were Let-7a, Let-7d, Let-7g, miR-16, RNU6, RNU48, miR-191, miR-223, miR-484, and miR-520d-5p. Once all samples were run for each potential HKG, the mean Ct and SD was calculated for all sample groups, allowing for comparison among HKGs. RESULTS: We screened 380 miRNAs by using microfluidic array technology (Applied Biosystems) in a discovery cohort of 20 colorectal cancer (CRC) patients, 10 patients each with breast cancer (BC), lung cancer (LC), pancreatic cancer (PC), 11 patients with colorectal adenoma, and 12 controls. The mean Ct and SD was calculated for RNU6, miR-520d-5p, miR-16, miR-191, miR-223, and miR-484, which were expressed in all samples. Let-7a, Let-7d, Let-7g, and RNU48 were only expressed in 26%, 7%, 10%, and 8% of samples, respectively, and therefore were deemed to be insufficiently reliable HKGs. Only miRNAs with >50% expression were included in this statistical analysis. U6 and miR-520d-5p had the most consistent Ct as well as the least SD. The use of both RNU6 and 520d-5p as HKGs provided reliable results. CONCLUSION: Among HKGs that were expressed in all samples, we suggest that RNU6 and miR-520d-5p were the best candidates for HKGs for studies of plasma miRNA because of the consistent and high Ct in all samples and a very narrow, reproducible SD.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":24398967,"Year":2014,"Title":"MicroRNA-301b promotes cell invasiveness through targeting TP63 in pancreatic carcinoma cells.","Abstract":"Recent studies have demonstrated that deregulated microRNA (miR) expression is implicated in the development of human cancers. In the aberrant miR expression, miR-301 is upregulated in cancers, such as pancreatic, colorectal and oral carcinoma. Based on this evidence, we investigated the contribution of miR-301 to pancreatic carcinoma and the novel target genes of miR-301 in pancreatic carcinoma. In this study, we analyzed the effects of enforced and inhibited expression of miR-301b expression in the Panc-1 and BxPC-3 cell lines. MiR-301b expression levels were associated with cell invasiveness in both cell lines. Additional experiments indicated that miR-301b influences invasiveness through CDH1. Moreover microRNA target search algorithms and experimental strategies suggested that miR-301b suppressed TP63 expression as a novel target of miR-301b. Remarkably, miR-301b was also found to be associated with NF-kappaB activity in both cell lines. In summary, overexpressed miR-301b may suppress TP63 expression and contributes to promote cell invasiveness and to enhance gemcitabine resistance in pancreatic carcinoma cells. Thus, miR-301b may have potential as a novel therapeutic target for cancer treatment due to its stimulatory effects on cell invasiveness.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-301"}
{"PMID":27022656,"Year":2015,"Title":"The loss of MiR-139-5p promotes colitis-associated tumorigenesis by mediating PI3K/AKT/Wnt signaling.","Abstract":"MiR-139-5p down-regulation has frequently been implicated in colorectal carcinoma. However, there is little known about its biological function between inflammation and cancer in vivo. Here, a transgenic murine model of colorectal carcinoma was used to investigate pathogenetic role of miR-139-5p in colitis and colitis-associated tumorigenesis. We showed that miR-139-5p knockout mice were higher sensitive to DSS-induced colitis and enhanced formation of intestinal neoplasia was observed when mice were exposed to AOM/DSS treatment. MiR-139-5p knockout mice exhibited an increased expression of genes involved in Wnt pathway. Such genes are closely associated with cell proliferation and differentiation, promoting the beta-catenin nuclear accumulation. Furthermore, biochemical studies in HCT-116 cells revealed that the over-expression of miR-139-5p inhibited the crosstalk between PI3K/AKT and Wnt pathway mediated by IGF-1R. Collectively, these findings indicate that miR-139-5p plays a crucial role in the development and progression of colitis-associated tumorigenesis and suggest that miR-139-5p may serve as a potential therapeutic target for the treatment of colitis-associated cancer in the future.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-139"}
{"PMID":22684455,"Year":2012,"Title":"miR-23a, a critical regulator of \"migR\"ation and metastasis in colorectal cancer.","Abstract":"Jahid and colleagues have shown that miR-23a promotes the transition from indolent to invasive colorectal cancer through inhibition of the MTSS1 tumor suppressor. This study reveals a novel role of miR-23a in the acceleration of colorectal cancer progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-23"}
{"PMID":27525719,"Year":2016,"Title":"G9a/RelB regulates self-renewal and function of colon-cancer-initiating cells by silencing Let-7b and activating the K-RAS/beta-catenin pathway.","Abstract":"Epigenetic reprogramming has been associated with the functional plasticity of cancer-initiating cells (CICs); however, the regulatory pathway has yet to be elucidated. A siRNA screen targeting known epigenetic genes revealed that G9a profoundly impairs the chemo-resistance, self-renewal and metastasis of CICs obtained from patients with colorectal cancer (CRC). Patients with elevated G9a were shown to face a high risk of relapse and poor survival rates. From a mechanistic perspective, G9a binds with and stabilizes RelB, thereby recruiting DNA methyltransferase 3 on the Let-7b promoter and repressing its expression. This leads to the activation of the K-RAS/beta-catenin pathway and regulates self-renewal and function of CICs. These findings indicate that the G9a/RelB/Let-7b axis acts as a critical regulator in the maintenance of CIC phenotypes and is strongly associated with negative clinical outcomes. Thus, these findings may have diagnostic as well as therapeutic implications for the treatment of chemotherapy-resistant or metastatic CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":26184038,"Year":2015,"Title":"IL6 Mediates Immune and Colorectal Cancer Cell Cross-talk via miR-21 and miR-29b.","Abstract":"UNLABELLED: Tumors are surrounded and infiltrated by a variety of stromal cell types, including fibroblasts, immune cells, and vascular endothelial cells, which interact with malignant cells to generate the tumor microenvironment (TME). This complex environment is thought to be regulated by the tumor in order to promote its survival and progression and thus constitutes a potential target for cancer therapy. However, intercellular communication within the microenvironment is not yet well understood. The current study investigates the mechanism by which cancer and immune cells communicate using an in vitro coculture model. It is demonstrated that IL6, a proinflammatory cytokine, secreted by immune cells promotes colorectal cancer cell invasiveness. In addition, in the presence of IL6, the cancer cells were able to secrete circulating miRNAs miR-21 and miR-29b to further induce immune cell IL6 production. Activated immune cells were also found to release miR-21 into the TME. Taken together, these mechanistic findings provide a better understanding of intercellular communication between immune and cancer cells in the TME and offer insight into some of the key players that mediate this cross-talk. IMPLICATIONS: This study demonstrates that cocultured cancer and immune cells communicate via IL6 and circulating miRNAs to sustain chronic inflammation and promote prometastatic cancer cell behavior. In addition, critical players are identified that mediate intercellular communication in the TME and suggest possible therapeutic approaches that target the microenvironment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":21532750,"Year":2011,"Title":"Differential expression of microRNAs in tumors from chronically inflamed or genetic (APC(Min/+)) models of colon cancer.","Abstract":"BACKGROUND: Chronic inflammation associated with ulcerative colitis predisposes individuals to increased colon cancer risk. The aim of these studies was to identify microRNAs that are aberrantly regulated during inflammation and may participate in transformation of colonic epithelial cells in the inflammatory setting. METHODOLOGY/PRINCIPAL FINDINGS: We have use quantitative PCR arrays to compare microRNA (miRNA) expression in tumors and control colonic epithelial cells isolated from distal colons of chronically inflamed mice and APC(Min/+) mice. Rank order statistics was utilized to identify differentially regulated miRNAs in tumors that arose due to chronic inflammation and/or to germline APC mutation. Eight high priority miRNAs were identified: miR-215, miR-137, miR-708, miR-31, and miR-135b were differentially expressed in APC tumors and miR-215, miR-133a, miR-467d, miR-218, miR-708, miR-31, and miR-135b in colitis-associated tumors. Four of these (miR-215, miR-708, miR-31, and miR-135b) were common to both tumors types, and dysregulation of these miRNAs was confirmed in an independent sample set. Target prediction and pathway analysis suggests that these microRNAs, in the aggregate, regulate signaling pathways related to MAPK, PI3K, WNT, and TGF-beta, all of which are known to be involved in transformation. CONCLUSIONS/SIGNIFICANCE: We conclude that these four miRNAs are dysregulated at some very early stage in transformation of colonic epithelial cells. This response is not dependent on the mechanism of initiation of transformation (inflammation versus germline mutation), suggesting that the miRNAs that we have identified are likely to regulate critical signaling pathways that are central to early events in transformation of colonic epithelial cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-215"}
{"PMID":22766504,"Year":2012,"Title":"MiR-145 regulates PAK4 via the MAPK pathway and exhibits an antitumor effect in human colon cells.","Abstract":"MicroRNAs (miRNAs) are regulators of numerous cellular events; accumulating evidence indicates that miRNAs play a key role in a wide range of biological functions, such as cellular proliferation, differentiation, and apoptosis in cancer. Down-regulated expression of miR-145 has been reported in colon cancer tissues and cell lines. The molecular mechanisms underlying miR-145 and the regulation of colon carcinogenesis remain unclear. In this study, we investigated the levels of miR-145 in human colon cancer cells using qRT-PCR and found markedly decreased levels compared to normal epithelial cells. We identified PAK4 as a novel target of miR-145 using informatics screening. Additionally, we demonstrated that miR-145 targets a putative binding site in the 3'UTR of PAK4 and that its abundance is inversely associated with miR-145 expression in colon cancer cells; we confirmed this relationship using the luciferase reporter assay. Furthermore, restoration of miR-145 by mimics in SW620 cells significantly attenuated cell growth in vitro, in accordance with the inhibitory effects induced by siRNA mediated knockdown of PAK4. Taken together, these findings demonstrate that miR-145 downregulates P-ERK expression by targeting PAK4 and leads to inhibition of tumor growth.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":30458288,"Year":2019,"Title":"A panel of seven-miRNA signature in plasma as potential biomarker for colorectal cancer diagnosis.","Abstract":"Colorectal cancer (CRC) has been one of the most commonly diagnosed cancers in global. The differential expression profiles of microRNAs (miRNAs) in CRC plasma of patients have the potential to serve as a diagnostic biomarker. We conducted a four-stage study to identify the potential plasma miRNAs for CRC detection. In the initial screening phase, Exiqon panel (miRCURY-Ready-to-Use-PCR-Human-panel-I+II-V1.M) including 3 CRC pools and 1 normal controls (NCs) pool were applied to acquire miRNA profiles. In the training stage (30 CRC VS. 30 NCs) and testing stage (79 CRC VS. 76 NCs), quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to conduct candidate miRNA profiles. Then the identified miRNAs were verified in external validation stage (30 CRC VS. 26 NCs). Expression levels of identified miRNAs were assessed in tissue samples (24 pairs) and plasma exosomes (18 CRC VS. 18 NCs). Receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic accuracy. Seven miRNAs (miR-103a-3p, miR-127-3p, miR-151a-5p, miR-17-5p, miR-181a-5p, miR-18a-5p and miR-18b-5p) were significantly overexpressed in CRC compared with NCs. Area under the ROC curve of the seven-miRNA signature was 0.762, 0.824 and 0.895 for the training, testing and the external validation stages, respectively. Additionally, miR-103a-3p, miR-127-3p, miR-17-5p and miR-18a-5p were discovered significantly up-regulated in CRC tissues; while miR-17-5p, miR-181a-5p, miR-18a-5p and miR-18b-5p were significantly elevated in CRC plasma exosomes. In conclusion, we established a seven-miRNA signature in the peripheral plasma for CRC detection.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-17"}
{"PMID":27738333,"Year":2016,"Title":"MiR-139-5p reverses CD44+/CD133+-associated multidrug resistance by downregulating NOTCH1 in colorectal carcinoma cells.","Abstract":"MiRNAs may promote or inhibit tumor recurrence and drug resistance. MiR-139-5p is reportedly downregulated in colorectal cancer patient samples, but it is unknown whether and how miR-139-5p regulates drug resistance. Cancer stem cells (CSCs) are postulated to be important promoters of multiple drug resistance (MDR). In this study, we established a MDR cell model which strongly expressed the CSC-associated biomarkers CD44 and CD133. MiR-139-5p expression was reduced in MDR cell lines, while overexpression of miR-139-5p reversed CD44+/CD133+-associated MDR. We also identified NOTCH1, an important protein for stem cell maintenance and function, as a direct target of miR-139-5p, both in vitro and in a knockout mouse model. Notch1 expression was upregulated in tumor samples and inversely correlated with expression of miR-139-5p. Silencing NOTCH1 exerted an effect similar to overexpression of miR-139-5p by inhibiting the CD44+ and CD133+ population and reversing the drug-resistant phenotype. In conclusion, miR-139-5p downregulated NOTCH1 signaling to reverse CD44+/CD133+-associated MDR in colorectal cancer cells. Given this insight into the miRNA regulation of MDR, miR-139-5p could be a promising therapeutic target for colorectal cancer therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-139"}
{"PMID":26646696,"Year":2016,"Title":"Signature miRNAs in colorectal cancers were revealed using a bias reduction small RNA deep sequencing protocol.","Abstract":"To explore the role of miRNAs in colorectal cancers (CRC), we have deep sequenced 48 pairs of frozen CRC samples, of which 44 pairs produced high quality sequencing data. By using a combined approach of our bias reduction small RNA (smRNA) deep sequencing protocol and Illumina small RNA TruSeq method for sample bar coding, we have obtained data from samples of relatively large size with bias reduced digital profile results. This novel approach allowed us to validate many previously published results using various techniques to profile miRNAs in CRC tissues or cell lines and to characterize 'true' miRNA signatures highly expressed in colon/rectum (CR) or CRC tissues. According to our results, miR-21, a miRNA that is up-regulated in CRC, and miR-143, a miRNA that is down-regulated in CRC, are the two miRNAs that dominated the miRNA population in CR tissues, and probably are also the most important miRNAs in CRCs. These two miRNAs, together with the other eight miRNAs, miR-148a, -194, -192, 200b, -200c, -10b, -26a, and -145, with descending expressing levels, constituted the top 10 highly expressed miRNAs in CR/CRC. Using TaqMan miRNA qPCR, we detected the relative expression of some of the CRC miRNAs in 10 CRC cell lines, validated their dysregulation under cancer condition, and provided possible explanation for their dysregulation, which could be caused by APC, KRAS, or TP53 mutations. We believe these results will provide a new direction in future miRNA-related CRC development studies, and application of miRNAs in CRC diagnosis/prognosis, and therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":22072615,"Year":2012,"Title":"microRNA-365, down-regulated in colon cancer, inhibits cell cycle progression and promotes apoptosis of colon cancer cells by probably targeting Cyclin D1 and Bcl-2.","Abstract":"Deregulated microRNAs participate in carcinogenesis and cancer progression, but their roles in cancer development remain unclear. In this study, miR-365 expression was found to be downregulated in human colon cancer tissues as compared with that in matched non-neoplastic mucosa tissues, and its downregulation was correlated with cancer progression and poor survival in colon cancer patients. Functional studies revealed that restoration of miR-365 expression inhibited cell cycle progression, promoted 5-fluorouracil-induced apoptosis and repressed tumorigenicity in colon cancer cell lines. Furthermore, bioinformatic prediction and experimental validation were used to identify miR-365 target genes and indicated that the antitumor effects of miR-365 were probably mediated by its targeting and repression of Cyclin D1 and Bcl-2 expression, thus inhibiting cell cycle progression and promoting apoptosis. These results suggest that downregulation of miR-365 in colon cancer may have potential applications in prognosis prediction and gene therapy in colon cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-365"}
{"PMID":27471839,"Year":2016,"Title":"A Highly Predictive Model for Diagnosis of Colorectal Neoplasms Using Plasma MicroRNA: Improving Specificity and Sensitivity.","Abstract":"OBJECTIVE: To develop a plasma-based microRNA (miRNA) diagnostic assay specific for colorectal neoplasms, building upon our prior work. BACKGROUND: Colorectal neoplasms [colorectal cancer (CRC) and colorectal advanced adenoma (CAA)] frequently develop in individuals at ages when other common cancers also occur. Current screening methods lack sensitivity, specificity, and have poor patient compliance. METHODS: Plasma was screened for 380 miRNAs using microfluidic array technology from a \"Training\" cohort of 60 patients, (10 each) control, CRC, CAA, breast cancer, pancreatic cancer, and lung cancer. We identified uniquely dysregulated miRNAs specific for colorectal neoplasia (P < 0.05, false discovery rate: 5%, adjusted alpha = 0.0038). These miRNAs were evaluated using single assays in a \"Test\" cohort of 120 patients. A mathematical model was developed to predict blinded sample identity in a 150 patient \"Validation\" cohort using repeat-sub-sampling validation of the testing dataset with 1000 iterations each to assess model detection accuracy. RESULTS: Seven miRNAs (miR-21, miR-29c, miR-122, miR-192, miR-346, miR-372, and miR-374a) were selected based upon P value, area under the curve (AUC), fold change, and biological plausibility. Area under the curve (+/-95% confidence interval) for \"Test\" cohort comparisons were 0.91 (0.85-0.96) between all neoplasia and controls, 0.79 (0.70-0.88) between colorectal neoplasia and other cancers, and 0.98 (0.96-1.0) between CRC and colorectal adenomas. In our \"Validation\" cohort, our mathematical model predicted blinded sample identity with 69% to 77% accuracy, 67% to 76% accuracy, and 86% to 90% accuracy for each comparison, respectively. CONCLUSIONS: Our plasma miRNA assay and prediction model differentiate colorectal neoplasia from patients with other neoplasms and from controls with higher sensitivity and specificity compared with current clinical standards.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":30073936,"Year":2019,"Title":"Computational Analysis of miRNA and their Gene Targets Significantly Involved in Colorectal Cancer Progression.","Abstract":"BACKGROUND: Globally, colorectal cancer (CRC) is the third most common cancer in women and the fourth most common cancer in men. Dysregulation of small non-coding miRNAs have been correlated with colon cancer progression. Since there are increasing reports of candidate miRNAs as potential biomarkers for CRC, this makes it important to explore common miRNA biomarkers for colon cancer. As computational prediction of miRNA targets is a critical initial step in identifying miRNA: mRNA target interactions for validation, we aim here to construct a potential miRNA network and its gene targets for colon cancer from previously reported candidate miRNAs, inclusive of 10 up- and 9 down-regulated miRNAs from tissues; and 10 circulatory miRNAs. METHODS: The gene targets were predicted using DIANA-microT-CDS and TarBaseV7.0 databases. Each miRNA and its targets were analyzed further for colon cancer hotspot genes, whereupon DAVID analysis and mirPath were used for KEGG pathway analysis. RESULTS: We have predicted 874 and 157 gene targets for tissue and serum specific miRNA candidates, respectively. The enrichment of miRNA revealed that particularly hsa-miR-424-5p, hsa-miR-96-5p, hsa-miR-1290, hsa-miR-224, hsa-miR-133a and has-miR-363-3p present possible targets for colon cancer hallmark genes, including BRAF, KRAS, EGFR, APC, amongst others. DAVID analysis of miRNA and associated gene targets revealed the KEGG pathways most related to cancer and colon cancer. Similar results were observed in mirPath analysis. A new insight gained in the colon cancer network pathway was the association of hsa-mir-133a and hsa-mir-96-5p with the PI3K-AKT signaling pathway. In the present study, target prediction shows that while hsa-mir-424-5p has an association with mostly 10 colon cancer hallmark genes, only their associations with MAP2 and CCND1 have been experimentally validated. CONCLUSION: These miRNAs and their targets require further evaluation for a better understanding of their associations, ultimately with the potential to develop novel therapeutic targets.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-133"}
{"PMID":20132431,"Year":2010,"Title":"Initial study of microRNA expression profiles of colonic cancer without lymph node metastasis.","Abstract":"OBJECTIVE: To investigate the difference of microRNA expression profiles between colonic cancer without lymph node metastasis and the para-cancerous control, to identify the specific microRNA associated with the cancer and to predict the carcinogenetic mechanism of microRNA on the basis of these results. METHODS: The microRNA (miRNA) were extracted and isolated from six specimens, including colonic cancerous and para-cancerous ones, all of which were confirmed to be without lymph node metastasis. Agilent microRNA microarrays consisting of 723 probes were used for screening the expression differences of microRNA. Data were analyzed using feature extraction software. The expression level of differentially expressed microRNA using quantitative real-time polymerase chain reaction (RT-PCR) was validated. RESULTS: A total of 14 miRNAs were found to be associated with colonic cancer, in which the expression of miR-106b, miR-135b, miR-18a, miR-18b, miR-196b, miR-19a, miR-224, miR-335, miR-424, miR-20a*, miR-301b and miR-374a were up-regulated and the expression of miR-378 and miR-378* were downregulated in colonic cancer tissues, compared with the para-cancerous control. The expression level of miR-18a and miR-135b were validated in accordance with the results of RT-PCR. CONCLUSION: The miRNAs are differentially expressed between colonic tumor tissues and para-cancerous tissues. Many of these miRNAs are expected to participate in the process of multiple tumorigenesis. These miRNAs could play an important role in the carcinogenesis of colon. These results provide new insights in human colorectal cancer genesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":24515657,"Year":2014,"Title":"Dysregulated miR1254 and miR579 for cardiotoxicity in patients treated with bevacizumab in colorectal cancer.","Abstract":"Methods for detecting circulating microRNAs (miRNAs), small RNAs that control gene expression, at high sensitivity and specificity in the blood have been reported in recent studies. The goal of this study was to determine if detectable levels of specific miRNAs are released into the circulation for bevacizumab-induced cardiotoxicity. A miRNA array analysis was performed using RNA isolated from 10 control patients in bevacizumab treatment, and n=10 patients have been confirmed to have bevacizumab-induced cardiotoxicity. From the array, we selected 19 candidate miRNA for a second validation study in 90 controls and 88 patients with bevacizumab-induced cardiotoxicity. Consistent with the data obtained from the microRNA array, circulating levels of five miRNAs were significantly increased in patients with bevacizumab-induced cardiotoxicity compared with controls. To confirm these data, we compared selected miRNAs in the plasma of patients with bevacizumab-induced cardiotoxicity with those of 66 patients with acute myocardial infarction (AMI). Moreover, we went on to analyze what factors may influence the levels of potential biomarker miRNAs. Consistent with the data obtained from the microRNA array, circulating levels of five miRNAs were significantly increased in patients with bevacizumab-induced cardiotoxicity compared with those of healthy bevacizumab treatment controls. However, only miRNA1254 and miRNA579 showed high specificity in the validation experiments. Moreover, we went on to analyze what factors may influence the levels of potential biomarker miRNAs. We identify two miRNAs that are specifically elevated in patients with bevacizumab-induced cardiotoxicity, miR1254 and miRNA579, and miRNA1254 shows the strongest correlation to the clinical diagnosis of bevacizumab-induced cardiotoxicity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-579"}
{"PMID":30786859,"Year":2019,"Title":"Small RNA expression from viruses, bacteria and human miRNAs in colon cancer tissue and its association with microsatellite instability and tumor location.","Abstract":"BACKGROUND: MicroRNAs (miRNA) and other small RNAs are frequently dysregulated in cancer and are promising biomarkers for colon cancer. Here we profile human, virus and bacteria small RNAs in normal and tumor tissue from early stage colon cancer and correlate the expression with clinical parameters. METHODS: Small RNAs from colon cancer tissue and adjacent normal mucosa of 48 patients were sequenced using Illumina high-throughput sequencing. Clinical parameters were correlated with the small RNA expression data using linear models. We performed a meta-analysis by comparing publicly available small RNA sequencing datasets with our original sequencing data to confirm the main findings. RESULTS: We identified 331 differentially expressed miRNAs between tumor and normal samples. We found that the major changes in miRNA expression between left and right colon are due to miRNAs located within the Hox-developmental genes, including miR-10b, miR-196b and miR-615. Further, we identified new miRNAs associated with microsatellite instability (MSI), including miR-335, miR-26 and miR-625. We performed a meta-analysis on all publicly available miRNA-seq datasets and identified 117 common miRNAs that were differentially expressed between tumor and normal tissue. The miRNAs miR-135b and miR-31 were the most significant upregulated miRNA in tumor across all datasets. The miRNA miR-133a was the most strongly downregulated miRNA in our dataset and also showed consistent downregulation in the other datasets. The miRNAs associated with MSI and tumor location in our data showed similar changes in the other datasets. Finally, we show that small RNAs from Epstein-Barr virus and Fusobacterium nucleatum are differentially expressed between tumor and normal adjacent tissue. CONCLUSIONS: Small RNA profiling in colon cancer tissue revealed novel RNAs associated with MSI and tumor location. We show that Fusobacterium nucleatum are detectable at the RNA-level in colon tissue, and that both Fusobacterium nucleatum and Epstein-Barr virus separate tumor and normal tissue.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-26"}
{"PMID":30005681,"Year":2018,"Title":"Regorafenib suppresses colon tumorigenesis and the generation of drug resistant cancer stem-like cells via modulation of miR-34a associated signaling.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the most prevalent malignancies in the world and developed drug resistance has represented one of the most challenging tasks for management. The current therapeutic regimens may select and enrich cancer stem-like cells (CSCs) resulting in the increased resistance against treatment, metastatic potential and mortality. Regorafenib is a multi-kinase inhibitor, an FDA-approved last-of-line treatment for patients with chemo-refractory metastatic CRC. However, regorafenib's potential effects on CSCs have not been fully elucidated. METHODS: Here, we developed two 5-FU resistant CRC cell lines, HCT-116R and DLD-1R and showed the increased CSCs characteristics such as increased side-population cells, tumor sphere formation and expression of stemness markers. These cell lines and CSCs properties were used for evaluating the potential of regorafenib in suppressing CSCs. RESULTS: We showed that regorafenib treatment decreased the stemness phenotypes including tumor sphere formation, and side-population, of both HCT-116R and DLD-1R cells. Additionally, regorafenib suppressed the cell viability in both cell lines synergistically with 5-FU. In vivo, the combination of regorafenib and 5-FU significantly suppressed the tumorigenesis and stemness markers of 5-FU resistant DLD-1R. Mechanistically, regorafenib-mediated effects were associated with the induction of tumor suppressor miR-34a and suppression of WNT/beta-catenin signaling. Our findings demonstrated that regorafenib treatment was associated with the increased level of miR-34a, resulting in reversing drug resistance and cancer-initiating cell phenotypes by degrading WNT/beta-catenin in CRC. CONCLUSION: Regorafenib might be a potential drug for colon cancer stem-like cells and it should be investigated in future clinical trials.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":26318304,"Year":2016,"Title":"Circulating levels of the miRNAs, miR-194, and miR-29b, as clinically useful biomarkers for colorectal cancer.","Abstract":"The microRNAs (miRNAs), miR-194 and miR-29b, have been shown to downregulate in colorectal cancer (CRC) and may identify and classify CRC patients as compared with those in control subjects. In the current study, we aimed to explore whether the serum levels of the miRNAs could be potential biomarkers for diagnosis and prognosis of CRC. A quantitative reverse-transcription polymerase chain reaction (qRT-PCR) assay was utilized to determine and compare serum levels of miR-194 and miR-29b in 55 patients with CRC and 55 control subjects. The correlations between levels of the miRNAs and clinicopathological stages of cancer were analyzed in patients. Receiver operating characteristic (ROC) curve and survival analyses were carried out, respectively, to determine diagnostic and prognostic values of the miRNAs. Serum levels of miR-194 and miR-29b were found to be significantly lower in CRC patients than those in control subjects (P < 0.0001). Moreover, serum levels of the miRNAs in patients were inversely correlated with the advanced TNM stages (P = 0.01). ROC curve and survival analyses revealed that reduced levels of the miRNAs could serve as diagnostic and prognostic biomarkers for patients with CRC (P = 0.0001). Serum levels of miR-194 and miR-29b may serve as potential biomarkers for diagnosis and prognosis of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-194"}
{"PMID":22241525,"Year":2012,"Title":"Differential microRNA expression tracks neoplastic progression in inflammatory bowel disease-associated colorectal cancer.","Abstract":"One of the most serious complications faced by patients with inflammatory bowel disease (IBD) is the potential development of colorectal cancer (CRC). There is a compelling need to enhance the accuracy of cancer screening of IBD patients. MicroRNAs (miRNAs) are small nonprotein-coding RNAs that play important roles in CRC oncogenesis. In this study, we report differential miRNA expression in IBD patients with associated CRC from non-neoplastic tissue to dysplasia and eventually cancer. In addition, we identify and examine the role of dysregulated miRNAs in the TP53 pathway. In our CD patients, six miRNAs were upregulated from non-neoplastic tissue to dysplasia, but downregulated from dysplasia to cancer (miR-122, miR-181a, miR-146b-5p, let-7e, miR-17, miR-143) (P < 0.001). Six differentially expressed miRNAs affected the TP53 pathway (miR-122, miR-214, miR-372, miR-15b, let-7e, miR-17) (P < 0.001). Using two human colon cancer cell lines (HT-29 and HCT-116), E2F1, an upstream regulator of TP53, was downregulated in both cell lines transfected with let-7e (P < 0.05) as well as in HCT-116 cells transfected with miR-17 (P < 0.05). Additionally, cyclin G, a cell-cycle regulator miR-122 target was downregulated in both cell lines (P < 0.05). Unique differentially expressed miRNAs were observed in CD-associated CRC progression. Six of these miRNAs had a tumorigenic effect on the TP53 pathway; the effect of three of which was studied using cell lines.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-372"}
{"PMID":17194750,"Year":2007,"Title":"A microRNA signature of hypoxia.","Abstract":"Recent research has identified critical roles for microRNAs in a large number of cellular processes, including tumorigenic transformation. While significant progress has been made towards understanding the mechanisms of gene regulation by microRNAs, much less is known about factors affecting the expression of these noncoding transcripts. Here, we demonstrate for the first time a functional link between hypoxia, a well-documented tumor microenvironment factor, and microRNA expression. Microarray-based expression profiles revealed that a specific spectrum of microRNAs (including miR-23, -24, -26, -27, -103, -107, -181, -210, and -213) is induced in response to low oxygen, at least some via a hypoxia-inducible-factor-dependent mechanism. Select members of this group (miR-26, -107, and -210) decrease proapoptotic signaling in a hypoxic environment, suggesting an impact of these transcripts on tumor formation. Interestingly, the vast majority of hypoxia-induced microRNAs are also overexpressed in a variety of human tumors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-27"}
{"PMID":28696255,"Year":2017,"Title":"Regulated Polarization of Tumor-Associated Macrophages by miR-145 via Colorectal Cancer-Derived Extracellular Vesicles.","Abstract":"Macrophages are polarized into functional classically activated and alternatively activated (M2) phenotypes depending on their microenvironment, and these cells play an important role in the immune system. M2-like polarization of tumor-associated macrophages (TAMs) is activated by various secretions from cancer cells; however, the interaction between cancer cells and TAMs is not well understood. Recent studies showed that cancer cell-derived extracellular vesicles (EVs) contribute to tumor development and modulation of the tumor microenvironment. In the current study, we investigated colorectal cancer-derived EVs containing miR-145 with respect to the polarization of TAMs. Colorectal cancer cells positively secreted miR-145 via EVs, which were taken up by macrophage-like cells. Interestingly, colorectal cancer-derived EVs polarized macrophage-like cells into the M2-like phenotype through the downregulation of histone deacetylase 11 An in vivo study showed that EV-treated macrophages caused significant enlargement of the tumor volumes. These findings suggest that colorectal cancer cells use miR-145 within EVs to efficiently modulate M2-like macrophage polarization and tumor progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":27633518,"Year":2016,"Title":"MicroRNA-330-5p negatively regulates ITGA5 expression in human colorectal cancer.","Abstract":"Colorectal cancer (CRC), one of the most prevalent malignant cancers, has high rates pf incidence and is the fourth leading cause of cancer-related deaths for both men and women worldwide. MicroRNAs (miRNAs) play critical roles in the development of various types of cancers. miRNA330-5p has been implicated in the progression of prostate, neuronal and pancreatic cancers by regulating proliferation, migration, invasion and epithelial-mesenchymal transition of cells. The purpose of the present study was to investigate the expression of miR-330-5p in CRC and identify its target gene(s) that may act in CRC tumorigenesis. We found that miR-330-5p expression was significantly lower in CRC tissues than that in adjacent non-tumorous tissues. Furthermore, we identified integrin alpha5 (ITGA5) as a new target of miR-330-5p and found that it inhibits ITGA5 expression by directly binding to the 3' untranslated region of ITGA5 mRNA. These results suggest that downregulation of miR-330-5p expression may affect CRC development via modulation of ITGA5 expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-330"}
{"PMID":23391324,"Year":2013,"Title":"Circulating miR-150 and miR-342 in plasma are novel potential biomarkers for acute myeloid leukemia.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are small (19-22-nt) single-stranded noncoding RNA molecules whose deregulation of expression can contribute to human disease including the multistep processes of carcinogenesis in human. Circulating miRNAs are emerging biomarkers in many diseases and cancers such as type 2 diabetes, pulmonary disease, colorectal cancer, and gastric cancer among others; however, defining a plasma miRNA signature in acute myeloblastic leukemia (AML) that could serve as a biomarker for diagnosis or in the follow-up has not been done yet. METHODS: TaqMan miRNA microarray was performed to identify deregulated miRNAs in the plasma of AML patients. Quantitative real-time RT-PCR was used to validate the results. Receiver-operator characteristic (ROC) curve analysis was conducted to evaluate the diagnostic accuracy of the highly and significantly identified deregulated miRNA(s) as potential candidate biomarker(s). RESULTS: The plasma expression level of let-7d, miR-150, miR-339, and miR-342 was down-regulated whilst that of let-7b, and miR-523 was up-regulated in the AML group at diagnosis compared to healthy controls. ROC curve analyses revealed an AUC (the areas under the ROC curve) of 0.835 (95% CI: 0.7119- 0.9581; P<0.0001) and 0.8125 (95% CI: 0.6796-0.9454; P=0.0005) for miR-150, and miR-342 respectively. Combined ROC analyses using these 2 miRNAs revealed an elevated AUC of 0.86 (95% CI: 0.7819-0.94; P<0.0001) indicating the additive effect in the diagnostic value of these 2 miRNAs. QRT-PCR results showed that the expression level of these two miRs in complete remission AML patients resembled that of healthy controls. CONCLUSIONS: Our findings indicated that plasma miR-150 and miR-342 are novel important promising biomarkers in the diagnosis of AML. These novel and promising markers warrant validation in larger prospective studies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-150"}
{"PMID":30598580,"Year":2018,"Title":"Relationship between Fusobacterium nucleatum, inflammatory mediators and microRNAs in colorectal carcinogenesis.","Abstract":"AIM: To examine the effect of Fusobacterium nucleatum (F. nucleatum) on the microenvironment of colonic neoplasms and the expression of inflammatory mediators and microRNAs (miRNAs). METHODS: Levels of F. nucleatum DNA, cytokine gene mRNA (TLR2, TLR4, NFKB1, TNF, IL1B, IL6 and IL8), and potentially interacting miRNAs (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p, miR-135b-5p) were measured by quantitative polymerase chain reaction (qPCR) TaqMan((R)) assays in DNA and/or RNA extracted from the disease and adjacent normal fresh tissues of 27 colorectal adenoma (CRA) and 43 colorectal cancer (CRC) patients. KRAS mutations were detected by direct sequencing and microsatellite instability (MSI) status by multiplex PCR. Cytoscape v3.1.1 was used to construct the postulated miRNA:mRNA interaction network. RESULTS: Overabundance of F. nucleatum in neoplastic tissue compared to matched normal tissue was detected in CRA (51.8%) and more markedly in CRC (72.1%). We observed significantly greater expression of TLR4, IL1B, IL8, and miR-135b in CRA lesions and TLR2, IL1B, IL6, IL8, miR-34a and miR-135b in CRC tumours compared to their respective normal tissues. Only two transcripts for miR-22 and miR-28 were exclusively downregulated in CRC tumour samples. The mRNA expression of IL1B, IL6, IL8 and miR-22 was positively correlated with F. nucleatum quantification in CRC tumours. The mRNA expression of miR-135b and TNF was inversely correlated. The miRNA:mRNA interaction network suggested that the upregulation of miR-34a in CRC proceeds via a TLR2/TLR4-dependent response to F. nucleatum. Finally, KRAS mutations were more frequently observed in CRC samples infected with F. nucleatum and were associated with greater expression of miR-21 in CRA, while IL8 was upregulated in MSI-high CRC. CONCLUSION: Our findings indicate that F. nucleatum is a risk factor for CRC by increasing the expression of inflammatory mediators through a possible miRNA-mediated activation of TLR2/TLR4.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-135"}
{"PMID":29199088,"Year":2018,"Title":"A MicroRNA Signature Associated With Metastasis of T1 Colorectal Cancers to Lymph Nodes.","Abstract":"Most T1 colorectal cancers treated by radical surgery can now be cured by endoscopic submucosal dissection. Although 70%-80% of T1 colorectal cancers are classified as high risk, <16% of these patients actually have lymph node metastases. Biomarkers are needed to identify patients with T1 cancers with the highest risk of metastasis, to prevent unnecessary radical surgery. We collected data from The Cancer Genome Atlas and identified 5 microRNAs (MIR32, MIR181B, MIR193B, MIR195, and MIR411) with significant changes in expression in T1 and T2 colorectal cancers with vs without lymph node metastases. Levels of the 5 microRNAs identified patients with lymph node invasion by T1 or T2 cancers with an area under the receiver operating characteristic curve (AUROC) value of 0.84. We validated these findings in 2 cohorts of patients with T1 cancers, using findings from histology as the reference. The 5-microRNA signature identified T1 cancers with lymph node invasion in cohort 1 with an AUROC value of 0.83, and in cohort 2 with an AUROC value of 0.74. When we analyzed biopsy samples from untreated patients, the 5-microRNA signature identified cancers with lymph node metastases with an AUROC value of 0.77. The 5-microRNA therefore identifies high-risk T1 colorectal cancers with a greater degree of accuracy than currently used pathologic features.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-181"}
{"PMID":28036302,"Year":2017,"Title":"High expression of miR-181c as a predictive marker of recurrence in stage II colorectal cancer.","Abstract":"INTRODUCTION: A standard treatment for stage II colorectal cancer (CRC) is surgical resection without adjuvant chemotherapy. However, the recurrence rate of these patients is approximately 20%. To date, there are no robust biomarkers suitable for predicting recurrence in stage II CRC patients. In this study, microRNAs (miRNAs) extracted from CRC tissues were examined for a possible biomarker to predict recurrence in stage II CRC patients. RESULTS: From the comprehensive analysis, 15 miRNAs were selected as candidates for further study. Regarding let-7a, -7d, -7e, miR-23c, -26b, -128a, -151-5p, and -181c, recurrence rates in training cohort patients with higher expression of these miRNAs isolated from their frozen tissues samples were significantly higher than those with lower expression (P < 0.05). According to multivariate analysis, the higher expression of miR-181c was detected as an independent predictive factor of recurrence (P = 0.001, OR: 9.43, 95% CI: 2.57-34.48). Results were similar in miR-181c extracted from FFPE tissues obtained from the training cohort (P = 0.003, OR: 7.46, 95% CI: 1.97-28.57). In the validation cohort using FFPE tissues, the recurrence rate in patients with higher miR-181c expression was significantly higher than those with lower miR-181c expression (P < 0.001). MATERIALS AND METHODS: Comprehensive analysis using a highly sensitive miRNA chip was initially performed to select candidate miRNAs associated with recurrence. Candidate miRNAs were analyzed by real-time RT-PCR using RNA from frozen and formalin-fixed, paraffin-embedded (FFPE) tissues. CONCLUSIONS: Higher expression of miR-181c may be a useful recurrence predictor of stage II CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":28105216,"Year":2016,"Title":"Identification of potential therapeutic targets for colorectal cancer by bioinformatics analysis.","Abstract":"The aim of the present study was to identify potential therapeutic targets for colorectal cancer (CRC). The gene expression profile GSE32323, containing 34 samples, including 17 specimens of CRC tissues and 17 of paired normal tissues from CRC patients, was downloaded from the Gene Expression Omnibus database. Following data preprocessing using the Affy and preprocessCore packages, the differentially-expressed genes (DEGs) between the two types of samples were identified with the Linear Models for Microarray Analysis package. Next, functional and pathway enrichment analysis of the DEGs was performed using the Database for Annotation Visualization and Integrated Discovery. The protein-protein interaction (PPI) network was established using the Search Tool for the Retrieval of Interacting Genes database. Utilizing WebGestalt, the potential microRNAs (miRNAs/miRs) of the DEGs were screened and the integrated miRNA-target network was built. A cohort of 1,347 DEGs was identified, the majority of which were mainly enriched in cell cycle-related biological processes and pathways. Cyclin-dependent kinase 1 (CDK1), cyclin B1 (CCNB1), MAD2 mitotic arrest deficient-like 1 (MAD2L1) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were prominent in the PPI network, while the over-represented genes in the integrated miRNA-target network were SRY (sex determining region Y)-box 4 (SOX4; targeted by hsa-mir-129), v-myc avian myelocytomatosis viral oncogene homolog (MYC; targeted by hsa-let-7c and hsa-mir-145) and cyclin D1 (CCND1; targeted by hsa-let-7b). CDK1, CCNB1 and CCND1 were also associated with the p53 signaling pathway. Overall, several genes associated with the cell cycle and p53 pathway were identified as biomarkers for CRC. CDK1, CCNB1, MAD2L1, BUB1B, SOX4, collagen type I alpha2 chain and MYC may play significant roles in CRC progression by affecting the cell cycle-related pathways, while CDK1, CCNB1 and CCND1 may serve as crucial regulators in the p53 signaling pathway. Furthermore, SOX4, MYC and CCND1 may be targets of miR-129, hsa-mir-145 and hsa-let-7c, respectively. However, further validation of these data is required.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":27081702,"Year":2016,"Title":"Serum miR-125b is a non-invasive predictive biomarker of the pre-operative chemoradiotherapy responsiveness in patients with rectal adenocarcinoma.","Abstract":"BACKGROUND: Therapeutic management of Locally Advanced Rectal Cancer (LARC) involves pre-operative chemoradiotherapy (pCRT) followed by surgery. However, after pCRT the complete pathological response is approximately 20%, whereas in 20 to 40% of patients the response is poor or absent. METHODS: Cancer biopsy specimens (n= 38) and serum samples (n= 34) obtained before pCRT from 38 LARC patients were included in the study. Patients were classified in responders (R, tumor regression grade [TRG] 1-2; n= 16) and non-responders (NR, TRG 3-5; n= 22) according to the pathological response observed upon surgery. We performed miRNA microarrays analysis on biopsy specimens, and validated the selected candidates both by qRT-PCR (tissue and serum) and by in situ hybridization (tissue, miR-125b) analyses. RESULTS: Eleven miRNAs were significantly different between R and NR (miR-154, miR-409-3p, miR-127-3p, miR-214*, miR-299-5p and miR-125b overexpressed in NR; miR-33a, miR-30e, miR-338-3p, miR-200a and miR-378 decreased). In particular, miR-125b resulted to be the best candidate to discriminate the two groups (AUC of 0.9026; 95% CI, 0.7618-1.043). Additionally, miR-125b serum levels were significantly overexpressed in NR patients compared to R (p-value=0.0087), with an excellent discriminating power (AUC of 0.782; 95% CI, 0.6123-0.9518). CONCLUSIONS: The obtained results further support the clinical impact of miRNA analysis. High miR-125b expression in tissue and serum were associated with a poor treatment response in LARC patients, therefore miR-125b could be considered as a possible novel non-invasive biomarker of response in LARC treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-127"}
{"PMID":28211508,"Year":2017,"Title":"MVP-mediated exosomal sorting of miR-193a promotes colon cancer progression.","Abstract":"Exosomes are emerging mediators of intercellular communication; whether the release of exosomes has an effect on the exosome donor cells in addition to the recipient cells has not been investigated to any extent. Here, we examine different exosomal miRNA expression profiles in primary mouse colon tumour, liver metastasis of colon cancer and naive colon tissues. In more advanced disease, higher levels of tumour suppressor miRNAs are encapsulated in the exosomes. miR-193a interacts with major vault protein (MVP). Knockout of MVP leads to miR-193a accumulation in the exosomal donor cells instead of exosomes, inhibiting tumour progression. Furthermore, miR-193a causes cell cycle G1 arrest and cell proliferation repression through targeting of Caprin1, which upregulates Ccnd2 and c-Myc. Human colon cancer patients with more advanced disease show higher levels of circulating exosomal miR-193a. In summary, our data demonstrate that MVP-mediated selective sorting of tumour suppressor miRNA into exosomes promotes tumour progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-193"}
{"PMID":29188362,"Year":2018,"Title":"The NF-kappaB signalling pathway in colorectal cancer: associations between dysregulated gene and miRNA expression.","Abstract":"BACKGROUND: The nuclear factor-kappa B (NF-kappaB) signalling pathway is a regulator of immune response and inflammation that has been implicated in the carcinogenic process. We examined differentially expressed genes in this pathway and miRNAs to determine associations with colorectal cancer (CRC). METHODS: We used data from 217 CRC cases to evaluate differences in NF-kappaB signalling pathway gene expression between paired carcinoma and normal mucosa and identify miRNAs that are associated with these genes. Gene expression data from RNA-Seq and miRNA expression data from Agilent Human miRNA Microarray V19.0 were analysed. We evaluated genes most strongly associated and differentially expressed (fold change (FC) of > 1.5 or < 0.67) that were statistically significant after adjustment for multiple comparisons. RESULTS: Of the 92 genes evaluated, 22 were significantly downregulated and nine genes were significantly upregulated in all tumours. Two additional genes (CD14 and CSNK2A1) were dysregulated in MSS tumours and two genes (CARD11 and VCAM1) were downregulated and six genes were upregulated (LYN, TICAM2, ICAM1, IL1B, CCL4 and PTGS2) in MSI tumours. Sixteen of the 21 dysregulated genes were associated with 40 miRNAs. There were 76 miRNA:mRNA associations of which 38 had seed-region matches. Genes were associated with multiple miRNAs, with TNFSRF11A (RANK) being associated with 15 miRNAs. Likewise several miRNAs were associated with multiple genes (miR-150-5p with eight genes, miR-195-5p with four genes, miR-203a with five genes, miR-20b-5p with four genes, miR-650 with six genes and miR-92a-3p with five genes). CONCLUSIONS: Focusing on the genes and their associated miRNAs within the entire signalling pathway provides a comprehensive understanding of this complex pathway as it relates to CRC and offers insight into potential therapeutic agents.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-150"}
{"PMID":22710713,"Year":2013,"Title":"MicroRNA-497 targets insulin-like growth factor 1 receptor and has a tumour suppressive role in human colorectal cancer.","Abstract":"Past studies have shown that amplified insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1-R) signalling has an important role in colorectal cancer (CRC) development, progression and resistance to treatment. In this report, we demonstrate that downregulation of microRNA-497 (miR-497) as a result of DNA copy number reduction is involved in upregulation of IGF1-R in CRC cells. MiR-497 and miR-195 of the miR-15/16/195/424/497 family that share the same 3' untranslated region (3'UTR) binding seed sequence and are predicted to target IGF1-R were concurrently downregulated in the majority of CRC tissues relative to paired adjacent normal mucosa. However, only overexpression of miR-497 led to suppression of the IGF1-R 3'UTR activity and downregulation of the endogenous IGF1-R protein in CRC cells. This was associated with inhibition of cell survival, proliferation and invasion, and increased sensitivity to apoptosis induced by various stimuli including the chemotherapeutic drugs cisplatin and 5-fluorouracil, and the death ligand tumour necrosis factor-related apoptosis-inducing ligand. The biological effect of miR-497 on CRC cells was largely mediated by inhibition of phosphatidylinositol 3-kinase/Akt signalling, as overexpression of an active form of Akt reversed its impact on cell survival and proliferation, recapitulating the effect of overexpression of IGF1-R. Downregulation of miR-497 and miR-195 appeared to associate with copy number loss of a segment of chromosome 17p13.1, where these miRs are located at proximity. Similarly to miR-195, the members of the same miR family, miR-424 that was upregulated, and miR-15a, miR-15b and miR-16 that were unaltered in expression in CRC tissues compared with paired adjacent normal mucosa, did not appear to have a role in regulating the expression of IGF1-R. Taken together, these results identify downregulation of miR-497 as an important mechanism of upregulation of IGF1-R in CRC cells that contributes to malignancy of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-15"}
{"PMID":25151966,"Year":2015,"Title":"miR-340 inhibits tumor cell proliferation and induces apoptosis by targeting multiple negative regulators of p27 in non-small cell lung cancer.","Abstract":"MicroRNAs (miRNAs) control cell cycle progression by targeting the transcripts encoding for cyclins, CDKs and CDK inhibitors, such as p27(KIP1) (p27). p27 expression is controlled by multiple transcriptional and posttranscriptional mechanisms, including translational inhibition by miR-221/222 and posttranslational regulation by the SCF(SKP2) complex. The oncosuppressor activity of miR-340 has been recently characterized in breast, colorectal and osteosarcoma tumor cells. However, the mechanisms underlying miR-340-induced cell growth arrest have not been elucidated. Here, we describe miR-340 as a novel tumor suppressor in non-small cell lung cancer (NSCLC). Starting from the observation that the growth-inhibitory and proapoptotic effects of miR-340 correlate with the accumulation of p27 in lung adenocarcinoma and glioblastoma cells, we have analyzed the functional relationship between miR-340 and p27 expression. miR-340 targets three key negative regulators of p27. The miR-340-mediated inhibition of both Pumilio family RNA-binding proteins (PUM1 and PUM2), required for the miR-221/222 interaction with the p27 3'-UTR, antagonizes the miRNA-dependent downregulation of p27. At the same time, miR-340 induces the stabilization of p27 by targeting SKP2, the key posttranslational regulator of p27. Therefore, miR-340 controls p27 at both translational and posttranslational levels. Accordingly, the inhibition of either PUM1 or SKP2 partially recapitulates the miR-340 effect on cell proliferation and apoptosis. In addition to the effect on tumor cell proliferation, miR-340 also inhibits intercellular adhesion and motility in lung cancer cells. These changes correlate with the miR-340-mediated inhibition of previously validated (MET and ROCK1) and potentially novel (RHOA and CDH1) miR-340 target transcripts. Finally, we show that in a small cohort of NSCLC patients (n=23), representative of all four stages of lung cancer, miR-340 expression inversely correlates with clinical staging, thus suggesting that miR-340 downregulation contributes to the disease progression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-340"}
{"PMID":29352232,"Year":2018,"Title":"The silent healer: miR-205-5p up-regulation inhibits epithelial to mesenchymal transition in colon cancer cells by indirectly up-regulating E-cadherin expression.","Abstract":"EMT represents the dominant program within advanced stages of colon cancer, where cells acquire migratory characteristics in order to invade secondary tissues and form metastasis. Where the majority of the therapeutic strategies are concentrated on the reduction of the tumor mass through different apoptotic mechanisms, the present study advocates an important role for miR-205-5p in impairment of colon cancer cells migration and restoration of the epithelial phenotype. Upon identification of a homogenous downregulated profile for miR-205-5p in colon adenocarcinoma patients, functional studies demonstrated that experimental upregulation of this sequence is able to significantly raise the levels of E-cadherin through direct inhibition of ZEB1. Moreover, the elevation in CDH1 expression was translated into functional parameters where cells lost their invasion and migratory characteristics and formed homogenous clusters through adhesion interactions. Survival analysis of colon adenocarcinoma patients revealed that low levels of miR-205-5p are associated with an unfavorable prognostic compared to those with increased expression, demonstrating the possible clinical utility of miR-205-5p replacement. Exogenous administration of miRNA mimics was not associated with significant changes in cell viability or inflammatory pathways. Therefore, the proposed strategy is aiming towards inhibition of metastasis and limitation of the tumor borders in advanced stages patients in order to prolong the survival time and to increase the efficiency of the current therapeutic strategies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-205"}
{"PMID":26695693,"Year":2016,"Title":"The Plasma microRNA miR-1914* and -1915 Suppresses Chemoresistant in Colorectal Cancer Patients by Down-regulating NFIX.","Abstract":"OBJECTIVE: We investigated mechanisms of colorectal cancer (CRC) chemoresistance to first-line chemotherapy (capecitabine plus oxaliplatin (XELOX)) and identified two putative chemoresistant microRNAs, miR-1914* and -1915, that are downregulated in plasma samples from patients with chemoresistant CRC. METHODS: A number of plasma samples from CRC patients were analyzed for the levels of miR-1914* and - 1915. Effects of stable and transient expression of 2 microRNAs in human chemoresistant CRC cell lines were analyzed. Tumor formation and chemoresistance in HCT116/5-Fu/OXA that did or did not express 2 microRNAs were analyzed in mice. Nuclear factor I/X (NFIX) was predicted to target the gene of 2 miRNAs and verified in vivo and in vitro. RESULTS: Plasma levels of miR-1914* and -1915 in chemoresistant CRC patients were different than levels in responders, and associated with clinical response. Overexpression of miR-1914* and -1915 in chemoresistant CRC cells reduced resistance to 5-FU and Oxaliplatin in vitro. The microRNAs suppressed chemoresistance in CRC tumors in mice by affecting cell growth, invasion, apoptosis and tumor suppressor function. miR-1914* and -1915 interacted with the 3'-untranslated region of NFIX and reduced NFIX its level in chemoresistant CRC cells. Overexpression of NFIX did not inhibit chemoresistant CRC cell motility and chemoresistant proteins when miR-1914* and -1915 were transfected. CONCLUSION: Plasma miR-1914* and -1915 interact with NFIX RNA and reduce its level in chemoresistant CRC cells to first-line chemotherapy. Up-regulation of miR-1914* and -1915 decreased the chemoresistance abilities of chemoresistant CRC cells. The plasma miR-1914* and -1915 may play a role in colorectal cancer therapy and diagnosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-1914"}
{"PMID":27082112,"Year":2016,"Title":"Infinity: An In-Silico Tool for Genome-Wide Prediction of Specific DNA Matrices in miRNA Genomic Loci.","Abstract":"MOTIVATION: miRNAs are potent regulators of gene expression and modulate multiple cellular processes in physiology and pathology. Deregulation of miRNAs expression has been found in various cancer types, thus, miRNAs may be potential targets for cancer therapy. However, the mechanisms through which miRNAs are regulated in cancer remain unclear. Therefore, the identification of transcriptional factor-miRNA crosstalk is one of the most update aspects of the study of miRNAs regulation. RESULTS: In the present study we describe the development of a fast and user-friendly software, named infinity, able to find the presence of DNA matrices, such as binding sequences for transcriptional factors, on ~65kb (kilobase) of 939 human miRNA genomic sequences, simultaneously. Of note, the power of this software has been validated in vivo by performing chromatin immunoprecipitation assays on a subset of new in silico identified target sequences (CCAAT) for the transcription factor NF-Y on colon cancer deregulated miRNA loci. Moreover, for the first time, we have demonstrated that NF-Y, through its CCAAT binding activity, regulates the expression of miRNA-181a, -181b, -21, -17, -130b, -301b in colon cancer cells. CONCLUSIONS: The infinity software that we have developed is a powerful tool to underscore new TF/miRNA regulatory networks. AVAILABILITY AND IMPLEMENTATION: Infinity was implemented in pure Java using Eclipse framework, and runs on Linux and MS Windows machine, with MySQL database. The software is freely available on the web at https://github.com/bio-devel/infinity. The website is implemented in JavaScript, PHP and HTML with all major browsers supported.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-130"}
{"PMID":25519012,"Year":2015,"Title":"Evaluation of genetic variants in miRNAs in patients with colorectal cancer.","Abstract":"BACKGROUND: Aberrant expression and structural alteration of miRNAs are considered to participate in cancer development. It has been suggested that common single-nucleotide polymorphisms (SNPs) in miRNAs are associated with susceptibility to several human diseases including colorectal cancer (CRC). METHODS: A case-control study at 157 CRC patients and 299 healthy controls of Greek origin was undertaken in order to investigate the association between the genotype and allelic frequencies of three common SNPs (rs2910164, rs11614913 and rs3746444) in pre-miRNAs, miR-146a, miR-196a2 and miR-499. RESULTS: The risk for CRC was significantly higher at the carriers of miR-146a rs2910164 CC genotype and C allele (p=0.02 and p< 0.001, respectively). None of the other performed analysis showed any statistically significant results. CONCLUSIONS: Our findings suggest that the rs2910164 polymorphism in pre-miRNA, miR-146a may be associated with the risk of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-499"}
{"PMID":28618945,"Year":2017,"Title":"The expression profiling of serum miR-92a, miR-375, and miR-760 in colorectal cancer: An Egyptian study.","Abstract":"Dysregulation in microRNA expression is a common feature in colorectal cancer. Due to the inconsistent results regarding serum miR-92a expression pattern and the insufficient studies on serum miR-375 and miR-760, we aimed in this study to investigate their expression profile and diagnostic and prognostic power in Egyptian colorectal cancer patients. The expression profile of miR-92a, miR-375, and miR-760 was determined in the sera of 64 colorectal cancer patients using quantitative real-time reverse transcription polymerase chain reaction in comparison to 27 healthy control subjects. The expression fold change of the studied microRNAs was correlated with patients' clinicopathological features. Receiver operating characteristic curve analysis was done to determine the role of these microRNAs in colorectal cancer diagnosis and follow-up according to the yielded area under the curve. The expression pattern of miR-92a was significantly upregulated (3.38 +/- 2.52, p < 0.0001), while both of miR-375 and 760 were significantly downregulated (-1.250 +/- 1.80, p< 0.0001; -1.710 +/- 1.88, p < 0.0001, respectively) in colorectal cancer than the control. MiR-92a was positively correlated ( r = 0.671, p = 0.0001), while miR-375 and miR-760 were inversely correlated ( r = -0.414, p = 0.001; r = -0.644, p = 0.0001) with advanced colorectal cancer stages. Receiver operating characteristic curve analysis disclosed the highest diagnostic potential for miR-760 to discriminate colorectal cancer patients and early-stage colorectal cancer from the control (area under the curve = 0.922 and 0.875, respectively), while the highest prognostic potential for discrimination between colorectal cancer stages was for miR-92a. In conclusion, serum level of miR-92a, miR-375, and miR-760 may serve as biomarkers of colorectal cancer in Egyptian patients with high diagnostic power for miR-760 and high prognostic power for miR-92a.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-92"}
{"PMID":22977632,"Year":2011,"Title":"Prognostic significance of microRNA gene polymorphisms in patients with surgically resected colorectal cancer.","Abstract":"MicroRNAs (miRNAs) are small 19- to 22-nucleotide sequences of RNA that participate in the regulation of cell differentiation, cell cycle progression and apoptosis. Although single-nucleotide polymorphisms (SNPs) in miRNA regions are considered unlikely to be functionally important, nucleotide variations within the sequences of primary (pri)- or precursor (pre)-miRNAs may affect miRNA processing and ultimately result in the modification of miRNA expression. The aim of this study was to investigate associations between four SNPs in pre-miRNA genes and the survival of colorectal cancer patients. A total of 407 colorectal patients were consecutively enrolled. DNA was extracted from blood specimens, and the hsa-mir-146aC>G, hsa-mir-149C>T, hsa-mir-196a2C>T and hsa-mir-499A>G polymorphisms were genotyped by PCR-RFLP. We were unable to identify independent prognostic SNPs for colorectal cancer. However, the heterozygous TC genotype of the 196a2C>T polymorphism was a significant risk factor for the overall survival of rectal cancer patients (HR=3.554, 95% CI 1.296-9.747, p=0.014). Further large-population studies are warranted to define the 196a2C>T polymorphism as a prognostic factor of rectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-146"}
{"PMID":22190470,"Year":2012,"Title":"A frequent somatic mutation in CD274 3'-UTR leads to protein over-expression in gastric cancer by disrupting miR-570 binding.","Abstract":"Inhibitory costimulatory molecule CD274 expresses in various cancers and contributes to cancer immune evasion by inhibiting T cell activation and proliferation, yet the regulatory mechanisms for CD274 overexpression in cancers are poorly understood. In this study, we discovered a novel mechanism of CD274 expression regulated by miR-570. A guanine-to-cytosine mutation at the 3'-UTR of CD274 mRNA led to CD274 overexpression by disrupting the miR-570 binding. The mutations were widely observed in cancers by sequencing of 276 gastrointestinal cancers (esophageal, gastric, colorectal, hepatocellular, and pancreatic cancers). This mutation was significantly associated with CD274 overexpression in gastric cancer (P = 1.44x10(-10)) and with the pathological features including differentiation grade, depth of tumor invasion, lymph node metastasis, and tumor-node-metastases (TNM) stage. These findings suggest a novel regulatory mechanism for CD274 overexpression in gastric cancer mediated by miR-570 and a somatic mutation in CD274 3'-UTR, and provide a new insight to gastric carcinogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-570"}
{"PMID":22641662,"Year":2012,"Title":"KRAS up-regulates the expression of miR-181a, miR-200c and miR-210 in a three-dimensional-specific manner in DLD-1 colorectal cancer cells.","Abstract":"BACKGROUND: We previously found that oncogenic KRAS induces increased expression of microRNAs (miRNAs), such as miR-200c and miR-221/222, in human colorectal cancer (CRC) HCT116 cells in a three-dimensional (3D)-specific manner, however, the regulation of miRNA expression through oncogenic KRAS in other types of CRC remains unclear. MATERIALS AND METHODS: The differential expression of 94 cancer-related miRNAs was examined in DLD-1 and DKO-4 cells (DLD-1 cells with a disrupted oncogenic KRAS) in 3D cultures. RESULTS: Increased miR-15b, miR-16, miR-23a, miR-24, miR-103 and miR-222 expression was observed in 3D and in 2D cultures. Of note, increased miR-181a, miR-200c and miR-210 expression was only observed in 3D cultures. Furthermore, miR-181a and miR-210 were significantly overexpressed in DLD-1 cells in 3D culture compared with those in HCT116 cells, and were significantly overexpressed in human CRC specimens. CONCLUSION: Oncogenic KRAS regulates 3D-specific miRNAs that are possibly associated with CRC development in vivo.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-181"}
{"PMID":30581274,"Year":2018,"Title":"Identification and prediction of novel non-coding and coding RNA-associated competing endogenous RNA networks in colorectal cancer.","Abstract":"AIM: To identify and predict the competing endogenous RNA (ceRNA) networks in colorectal cancer (CRC) by bioinformatics analysis. METHODS: In the present study, we obtained CRC tissue and normal tissue gene expression profiles from The Cancer Genome Atlas project. Differentially expressed (DE) genes (DEGs) were identified. Then, upregulated and downregulated miRNA-centered ceRNA networks were constructed by analyzing the DEGs using multiple bioinformatics approaches. DEmRNAs in the ceRNA networks were identified in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using KEGG Orthology Based Annotation System 3.0. The interactions between proteins were analyzed using the STRING database. Kaplan-Meier survival analysis was conducted for DEGs and real time quantitative polymerase chain reaction (RT-qPCR) was also performed to validate the prognosis-associated lncRNAs in CRC cell lines. RESULTS: Eighty-one DElncRNAs, 20 DEmiRNAs, and 54 DEmRNAs were identified to construct the ceRNA networks of CRC. The KEGG pathway analysis indicated that nine out of top ten pathways were related with cancer and the most significant pathway was \"colorectal cancer\". Kaplan-Meier survival analysis showed that the overall survival was positively associated with five DEGs (IGF2-AS, POU6F2-AS2, hsa-miR-32, hsa-miR-141, and SERPINE1) and it was negatively related to three DEGs (LINC00488, hsa-miR-375, and PHLPP2). Based on the STRING protein database, it was found that SERPINE1 and PHLPP2 interact with AKT1. Besides, SERPINE1 can interact with VEGFA, VTN, TGFB1, PLAU, PLAUR, PLG, and PLAT. PHLPP2 can interact with AKT2 and AKT3. RT-qPCR revealed that the expression of IGF2-AS, POU6F2-AS2, and LINC00488 in CRC cell lines was consistent with the in silico results. CONCLUSION: CeRNA networks play an important role in CRC. Multiple DEGs are related with clinical prognosis, suggesting that they may be potential targets in tumor diagnosis and treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-375"}
{"PMID":31402962,"Year":2019,"Title":"Discovery of core genes in colorectal cancer by weighted gene co-expression network analysis.","Abstract":"The aim of the present study was to investigate the interactions among messenger RNAs (mRNAs), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs) in colorectal cancer (CRC), in order to examine its underlying mechanisms. The raw gene expression data was downloaded from the Gene Expression Omnibus (GEO) database. An online tool, GEO2R, which is based on the limma package, was used to identify differentially expressed genes. The co-expression between lncRNAs and mRNAs was identified utilizing the weighted gene co-expression analysis package of R to construct a coding non-coding (CNC) network. The function of the genes in the CNC network was determined by performing Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways enrichment analysis. The interactions among miRNAs, mRNAs and lncRNAs were predicted using Lncbase and mirWalk to construct the competing endogenous RNA (ceRNA) network. The expression of the genes involved in the ceRNA network was further validated in The Cancer Genome Atlas dataset. A total of 3,183 dysregulated mRNAs, 78 dysregulated miRNAs and 2,248 dysregulated lncRNAs were screened in two GEO datasets. Combined with the results of the dysregulated genes, 169 genes were selected to construct the CNC network. 'p53 signaling pathway' and the 'cell cycle' were the most significant enriched pathways in the genes involved in the CNC network. Finally, a validated ceRNA network composed of 2 lncRNAs (MIR22HG and RP11-61I13.3), 5 miRNAs (hsa-miR-765, hsa-miR-198, hsa-miR-125a-3p, hsa-miR-149-3p and hsa-miR-650) and 5 mRNAs (ANK2, BTK, GBP2, PCSK5 and PDK4) was obtained. In conclusion, MIR22HG may regulate PCSK5, BTK and PDK4, and RP11-61I13.3 may regulate the ANK2, GBP2, PCSK5 through sponging miRNAs to act on the progression of CRC, and the potential function of these genes have been revealed. However, the diagnostic and prognostic value of these genes requires further validation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-198"}
{"PMID":23019418,"Year":2012,"Title":"MiR-9, -31, and -182 deregulation promote proliferation and tumor cell survival in colon cancer.","Abstract":"Several microRNAs (miRNAs) are known to be deregulated in colon cancer, but the mechanisms behind their potential involvement on proliferation and tumor cell survival are unclear. The present study aimed to identify miRNAs with functional implications for development of colon cancer. The cell proliferation and apoptosis were examined following perturbations of miRNA levels by employing a comprehensive miRNA library screen. miRNAs nominated for relevance to colon cancer were validated on expression and functional levels. By integrating the effect of miRNA up-regulation with the endogenous miRNA expression levels within the HT29, HCT116, and SW480 colon cancer cell lines, we identified miRNAs controlling cell proliferation (n = 53) and apoptosis (n = 93). From these functionally nominated miRNAs, we narrowed the list to 10 oncogene- and 20 tumor suppressor-like miRNAs that were also differentially expressed between colon cancer (n = 80) and normal colonic mucosa (n = 20). The differential expressions of miR-9, miR-31, and miR-182 were successfully validated in a series of colon carcinomas (n = 30) and polyps (n = 10) versus normal colonic mucosa (n = 10), whereas the functional effect was confirmed in an in-depth validation using different cell viability and apoptotic markers. Several transcription factors and genes regulating cell proliferation were identified as putative target genes by integrative miRNA/mRNA expression analysis obtained from the same colon cancer patient samples. This study suggests that deregulated expression of miR-9, miR-31, and miR-182 during carcinogenesis plays a significant role in the development of colon cancer by promoting proliferation and tumor cell survival.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-182"}
{"PMID":18695884,"Year":2008,"Title":"Micro-RNAs miR125b and miR137 are frequently upregulated in response to capecitabine chemoradiotherapy of rectal cancer.","Abstract":"There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-339"}
{"PMID":24938624,"Year":2014,"Title":"MicroRNA target prediction: theory and practice.","Abstract":"The present study is one of the few that includes tissue samples in the evaluation of target prediction algorithms designed to detect microRNA (miRNA) sequences that might interact with particular messenger RNA (mRNA) sequences. Twelve different target prediction tools were used to find miRNA sequences that might interact with CCL20 gene expression. Different algorithms predicted controversial miRNA sequences for CCL20 regulation due to a different weighting of parameters. Hsa-miR-21 and hsa-miR-145 suggested by four or more programs were chosen for further investigation. Possible real interaction of these miRNA sequences with CCL20 gene expression was monitored using luciferase assays and expression analyses of tissue samples of colorectal adenocarcinoma by either qRT-PCR or ELISA. Folding status of seed-binding sites in complete mRNA and 3'UTR of CCL20 was predicted. Prediction of miRNA expression was attempted based on CCL20 expression data. Eight of the target prediction tools forecasted a role for hsa-miR-21 and four mentioned hsa-miR-145 in CCL20 gene regulation. Laboratory experimentation showed that CCL20 may serve as a target of hsa-miR-21 but not hsa-miR-145. Expression of the molecules resulted in no clear assertion. Folding of seed-binding sites was predicted to be relatively constant for the complete mRNA and 3'UTR. Predicting miRNA expression based on target gene expression was impossible. This might be attributable to the fact that effects of miRNA activity may oscillate between gene product repression and activation. Additional systematic studies are needed to address this issue.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":24510588,"Year":2014,"Title":"Role of miR-200 family members in survival of colorectal cancer patients treated with fluoropyrimidines.","Abstract":"BACKGROUND AND OBJECTIVES: Surgery is the standard treatment for colorectal cancer (CRC), and adjuvant chemotherapy has been shown to be effective in stage III but less so in stage II. We have analyzed the expression of the miR-200 family in tissue samples from resected CRC patients and correlated our findings with survival to adjuvant treatment with fluoropyrimidines. METHODS: Tumor tissue samples were obtained from 127 surgically resected patients with stage I-III CRC. miRNA detection was performed using TaqMan MicroRNA assays. RESULTS: High levels of miR-200a and miR-200c were associated with longer overall survival, while high levels of miR-429 correlated with longer overall and disease-free survival (DFS). In the subgroup of 56 patients treated with fluoropyrimidines and in the smaller subgroup of 32 stage II patients treated with fluoropyrimidines, those with high levels of miR-200a, miR-200c, miR-141, or miR-429 had significantly longer overall and DFS. Low miR-429 levels were identified as an independent prognostic marker. High levels of miR-429 combined with 5-fluorouracil inhibited cell invasion in LOVO cells. CONCLUSIONS: miR-200a, miR-200c, miR-141, and miR-429 expression levels may identify CRC patients, including those with stage II disease, who are most likely to benefit from adjuvant chemotherapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-200"}
{"PMID":25420938,"Year":2015,"Title":"MicroRNA-155 promotes the proliferation and invasion abilities of colon cancer cells by targeting quaking.","Abstract":"The increasing expression of microRNA155 (miR155) and decreasing expression of RNAbinding protein quaking (QKI) in colon cells have been observed previously. In this study, we attempted to establish the correlation between miR155 and QKI. In addition, we assessed whether the expression of miR155 and QKI is linked to the proliferation and invasion capabilities of colon cells. Firstly, nineteen tumor samples, divided into two groups according to the presence or absence of lymphatic metastasis, were obtained from colon cancer patients at the First Affiliated Hospital of Wenzhou Medical University, China. The expression level of miR155 and QKI was measured by quantitative polymerase chain reaction (qPCR). Secondly, the GES1, SW480 and COLO205 cell lines were cultured and the expression level of QKI and miR155 was also assessed by qPCR. Thirdly, a luciferase reporter gene assay was performed to detect the association between miR155 and QKI, and qPCR and western blot analysis were performed to confirm the effects of miR155 on the expression of QKI at the mRNA and protein level. Subsequently, the SW480 cells were used in the following experiments. Following treatment with miR155 inhibitor and QKI overexpression vector, western blot analysis, propidium iodide (PI) staining and a cell scratch assay were carried out to assess the effects of miR155 on the proliferation and invasion potential of colon cancer cells. qPCR findings revealed higher miR155 expression and lower QKI expression in colon cancer tissues as well as the colon cancer cell lines SW480 and COLO205. The relative luciferase activity of the 3' untranslated region (3'UTR) was decreased by approximately 45% when SW480 cells stimulated by mimicmiR155 were combined with the wildtype 3'UTR constructs. In addition, when the cells were treated with mimicmiR155, QKI expression was significantly decreased at the mRNA and protein level. These outcomes revealed that miR155 decreased the production of QKI by acting on the 3'UTR of the QKI gene. Furthermore, PI staining and the cell scratch assay revealed that miR155 influenced the cell cycle and invasion abilities of colon cancer cells by directly targeting QKI and decreased the production of QKI by acting on the 3'UTR of the QKI gene. This study has demonstrated the correlation between miR155 and QKI, in which miR155 regulates the cell cycle and invasion ability of colon cancer cells via the modulation of QKI expression. Our study provides novel therapeutic strategies for colon cancer therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-155"}
{"PMID":19287964,"Year":2009,"Title":"Over- and under-expressed microRNAs in human colorectal cancer.","Abstract":"MicroRNAs (miRNAs) constitute a class of small (21-23 nucleotides) noncoding RNAs that function as post-transcriptional gene regulators. It is becoming increasingly clear that altered miRNA expression correlates with the pathogenesis of cancers. The purpose of this study was to determine the up-regulated miRNAs in human colorectal cancer. Total RNA was isolated from cancer tissues and corresponding noncancerous tissues from surgically resected colorectal cancers. The expression profiles of miRNAs were determined using a miRNA microarray containing 455 human miRNA probes. The expression status of selected miRNAs in paired clinical samples was then investigated by real-time RT-PCR. Twenty-one miRNAs were identified by miRNA array analysis as overexpressed in colorectal cancer tissues compared to normal epithelial tissues. Among them, the expression of miR-31, miR-183, miR-17-5p, miR-18a, miR-20a and miR-92 were confirmed to be significantly higher in cancer tissues than in normal tissues (P<0.05). In contrast, the expression of miR-143 and miR-145 in cancer tissues were significantly lower than in normal tissues (P<0.05). The miR-18a overexpression group tended to have a poorer clinical prognosis than the low expression group (P=0.07). We identified miRNAs that were overexpressed or under-expressed in colorectal cancers and which may be correlated with colorectal carcinogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-17"}
{"PMID":26038573,"Year":2015,"Title":"Serum miR-21, miR-29a, and miR-125b Are Promising Biomarkers for the Early Detection of Colorectal Neoplasia.","Abstract":"PURPOSE: Circulating microRNAs (miRNA) are emerging as promising diagnostic biomarkers for colorectal cancer, but their usefulness for detecting early colorectal neoplasms remains unclear. This study aimed to identify serum miRNA biomarkers for the identification of patients with early colorectal neoplasms. EXPERIMENTAL DESIGN: A cohort of 237 serum samples from 160 patients with early colorectal neoplasms (148 precancerous lesions and 12 cancers) and 77 healthy subjects was analyzed in a three-step approach that included a comprehensive literature review for published biomarkers, a screening phase, and a validation phase. RNA was extracted from sera, and levels of miRNAs were examined by real-time RT-PCR. RESULTS: Nine miRNAs (miR-18a, miR-19a, miR-19b, miR-20a, miR-21, miR-24, miR-29a, miR-92, and miR-125b) were selected as candidate biomarkers for initial analysis. In the screening phase, serum levels of miR-21, miR-29a, and miR-125b were significantly higher in patients with early colorectal neoplasm than in healthy controls. Elevated levels of miR-21, miR-29a, and miR-125b were confirmed in the validation phase using an independent set of subjects. Area under the curve (AUC) values for serum miR-21, miR-29a, miR-125b, and their combined score in discriminating patients with early colorectal neoplasm from healthy controls were 0.706, 0.741, 0.806, and 0.827, respectively. Serum levels of miR-29a and miR-125b were significantly higher in patients who had only small colorectal neoplasms (<\/=5 mm) than in healthy subjects. CONCLUSIONS: Because serum levels of miR-21, miR-29a, and miR-125b discriminated patients with early colorectal neoplasm from healthy controls, our data highlight the potential clinical use of these molecular signatures for noninvasive screening of patients with colorectal neoplasia.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-125"}
{"PMID":22529906,"Year":2012,"Title":"Differential expression of miRNAs in colorectal cancer: comparison of paired tumor tissue and adjacent normal mucosa using high-throughput sequencing.","Abstract":"We present the results of a global study of dysregulated miRNAs in paired samples of normal mucosa and tumor from eight patients with colorectal cancer. Although there is existing data of miRNA contribution to colorectal tumorigenesis, these studies are typically small to medium scale studies of cell lines or non-paired tumor samples. The present study is to our knowledge unique in two respects. Firstly, the normal and adjacent tumor tissue samples are paired, thus taking into account the baseline differences between individuals when testing for differential expression. Secondly, we use high-throughput sequencing, thus enabling a comprehensive survey of all miRNAs expressed in the tissues. We use Illumina sequencing technology to perform sequencing and two different tools to statistically test for differences in read counts per gene between samples: edgeR when using the pair information and DESeq when ignoring this information, i.e., treating tumor and normal samples as independent groups. We identify 37 miRNAs that are significantly dysregulated in both statistical approaches, 19 down-regulated and 18 up-regulated. Some of these miRNAs are previously published as potential regulators in colorectal adenocarcinomas such as miR-1, miR-96 and miR-145. Our comprehensive survey of differentially expressed miRNAs thus confirms some existing findings. We have also discovered 16 dysregulated miRNAs, which to our knowledge have not previously been associated with colorectal carcinogenesis: the following significantly down-regulated miR-490-3p, -628-3p/-5p, -1297, -3151, -3163, -3622a-5p, -3656 and the up-regulated miR-105, -549, -1269, -1827, -3144-3p, -3177, -3180-3p, -4326. Although the study is preliminary with only eight patients included, we believe the results add to the present knowledge on miRNA dysregulation in colorectal carcinogenesis. As such the results would serve as a robust training set for validation of potential biomarkers in a larger cohort study. Finally, we also present data supporting the hypothesis that there are differences in miRNA expression between adenocarcinomas and neuroendocrine tumors of the colon.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-549"}
{"PMID":30119180,"Year":2018,"Title":"Exosome-mediated miR-200b promotes colorectal cancer proliferation upon TGF-beta1 exposure.","Abstract":"Exosome are emerging mediators of intercellular communication. Cancer-secreted exosome has an effect on the exosome donor cells and support cancer growth and metastasis. Here, we examine the TGF-beta1, a multifunctional cytokine involved in the regulation of cellular signaling pathways in human cancers, significantly contributes to upregulate miR-200b in exosome from colorectal cancer cell lines. The miR-200b enriched in exosome can be transferred into a new target cell to facilitating the colorectal cancer cells proliferation. Further studies showing that the exosomal miR-200b could directly target 3'-UTRs of p27 and RND3 resulted in knockdown of respective target proteins in recipient cells. Remarkably, the overexpression of p27/kip1 in HCT-116 cell, not RND3, resulted in effectively inhibited cell proliferation which induced by exosomal miR-200b. Moreover, animal experiment studies also confirmed a stimulating effect of exosomal miR-200b on colorectal cancer cell-derived xenografts. The expression p27/kip1 have decreased in tumors xenografts after injected with exosomal miR-200b. Our observations offer an evidence that whereby exosomal specific miRNA could amplify the proliferative element into the neighboring or distant cells to effective tumor growth.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-200"}
{"PMID":29207180,"Year":2018,"Title":"MicroRNA-411 inhibits malignant biological behaviours of colorectal cancer cells by directly targeting PIK3R3.","Abstract":"Colorectal cancer (CRC) is the third most common cancer and the fourth leading cause of cancer-related mortality worldwide. Aberrant expression of miRNAs play important roles in the development and progression of various types of cancers by modulating oncogenic and tumour-suppressor pathways. Therefore, exploring the functions of microRNAs (miRNAs) that specifically contribute to CRC tumourigenesis and tumour development would greatly aid in obtaining more information on CRC and provide new targets for its diagnosis and treatment. miRNA-411 (miR-411) was previously observed to be aberrantly expressed in multiple human cancers. However, the expression pattern, function and underlying molecular mechanism of miR-411 in CRC remain unclear. Therefore, the present study was performed to detect miR-411 expression, investigate the biological roles of miR-411 and identify its mechanism of action in CRC cells. Here, miR-411 expression was significantly downregulated in human CRC tissues and cell lines, and low levels of miR-411 were correlated with lymph node metastasis, distant metastasis and TNM stage. Resumed expression of miR-411 suppressed cell proliferation and invasion but promoted apoptosis in CRC. Additionally, phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) was identified as a direct target of miR-411 in CRC. PIK3R3 was upregulated in the CRC tissues and inversely correlated with miR-411 expression. Downregulation of PIK3R3 had tumour-suppressive effects similar to those of miR-411 overexpression in CRC. Moreover, upregulation of PIK3R3 could rescue the tumour-suppressing effects of miR-411 overexpression in CRC cells. More importantly, miR-411 specifically suppressed the activation of the AKT/mTOR signalling pathway in CRC. Therefore, miR-411 functions as a tumour-suppressive miRNA by directly targeting PIK3R3 and indirectly regulating AKT/mTOR signalling pathway. miR-411 may serve as a new therapeutic target for patients with CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-411"}
{"PMID":29041002,"Year":2017,"Title":"Astragaloside IV Induced miR-134 Expression Reduces EMT and Increases Chemotherapeutic Sensitivity by Suppressing CREB1 Signaling in Colorectal Cancer Cell Line SW-480.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. Although chemotherapy is the primary means in colorectal cancer treatment, it is burdenerd by adverse drug effects. Drug-resistance is one of the most important challenges for chemotherapy and epithelial-mesenchymal transition (EMT) plays critical role in the development of drug resistance. AIMS: The aim of this study was to investigate the mechanisms underlying the effect of astragaloside IV (AS-IV) on miR-134 expression, EMT and chemotherapeutic sensitivity in CRC. METHODS: Cell proliferation, transfection assay, western blot, real-time PCR, cell migration and invasion assay and luciferase reporter assay were used to detect the effects of AS-IV on CRC. RESULTS: AS-IV significantly inhibited CRC cell migration and invasion by inducing miR-134 expression. Moreover, AS-IV and miR-134 increased the sensitivity of CRC tumors to oxaliplatin (OXA) chemotherapy. cAMP responsive element-binding protein 1 (CREB1), which was required for CRC cells migration, invasion and drug sensitivity, was significantly down-regulated by AS-IV. CONCLUSIONS: Our results indicated that AS-IV inhibited CRC EMT by inducing miR-134 expression which significantly down-regulated the CREB1 signaling pathway, and therefore increased the sensitivity to chemotherapy. Our findings provided new insight into the mechanisms of chemotherapy-resistant CRC, and may open new therapeutic options in the treatment of this devastating disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-134"}
{"PMID":26312830,"Year":2015,"Title":"Circulating plasma microRNAs as a screening method for detection of colorectal adenomas.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNA molecules. Reduced or increased levels of specific miRNAs are observed in colon and other cancers, supporting their role in carcinogenesis. Detection of colorectal polyps is the cornerstone of the Bowel Cancer Screening Programme in the UK. However, uptake of screening nationally remains under 60%. We aimed to see whether circulating plasma miRNAs can be used to screen for patients with colorectal polyps, adenomas, or both. METHODS: Blood samples were taken from patients from the Bowel Cancer Screening Programme (asymptomatic but faecal occult blood testing [FOBt] positive). Plasma RNA was extracted, target miRNAs (19a, 98, 146b, 186, 191, 222*, 331-5p, 452, 625, 664, 1247) were identified on pooled case miRNA assay cards, and miRNA fraction was quantified by quantitative RT-PCR assay. Results were compared with endoscopy reports and with histology of any polyps identified and removed. Analysis was done with Excel (2011) and SPSS (version 20) software. FINDINGS: 210 patients were included (117 with polyps, 12 with cancer, 81 healthy controls [FOBt positive]). The miRNA panel showed significant differences in expression (on t testing) for patients compared with controls for those with polyps, cancer, or both (miR-19a, p=0.0184; miR-98, p=0.0206; miR-146b, p=0.0029; miR-186, p=0.0006; miR-62,5 p=0.0008), polyps (miR-19a, p=0.0233; miR-98, p=0.0224; miR-146b, p=0.003; miR-186, p=0.0004; miR-625, p=0.001), adenomas (miR-19a, p=0.0339; miR-98, p=0.0266; miR-146b, p=0.0045; miR-186, p=0.0008; miR-625, p=0.0049), multiple adenomas (both sides of colon; miR-146b, p=0.0194; miR-186, p=0.0226; miR-625, p=0.0013), and right-sided adenomas (miR-98, p=0.031; miR-146b, p=0.0076; miR-186, p=0.0041; miR-331-5p, p=0.0142; miR-625, p=0.0049). Receiver operating characteristic analysis showed sensitivity of 60% or more, and specificity of 86% or more for men with polyps, men with adenomas, all patients with haemorrhoids or diverticulosis and polyps, and all patients with haemorrhoids or diverticulosis and adenomas. INTERPRETATION: The target miRNAs that we identified showed significant differences in expression levels for patients with polyps and patients with adenomas from controls. Use of this panel has potential as a screening test. FUNDING: Bowel Disease Research Foundation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-62"}
{"PMID":29386092,"Year":2018,"Title":"miR-522-3p Promotes Tumorigenesis in Human Colorectal Cancer via Targeting Bloom Syndrome Protein.","Abstract":"miR-522-3p is known to degrade bloom syndrome protein (BLM) and enhance expression of other proto-oncogenes, leading to tumorigenesis. This study aimed to investigate the molecular mechanisms of miR-522-3p in human colorectal cancer (CRC) cells. Expressions of miR-522-3p in CRC and adjacent tissues, as well as in normal human colon epithelial cell line (FHC) and five CRC cell lines, were detected. Human CRC cell lines, HCT-116 and HT29, were transfected with miR-522-3p mimic, inhibitor, or scrambled controls. Then cell viability, apoptosis, cell cycle progression, and the expressions of c-myc, cyclin E, CDK2, and BLM were assessed. It was found that miR-522-3p was highly expressed in CRC tissues when compared to adjacent nontumor tissues and was highly expressed in CRC cell lines when compared to FHC cells. miR-522-3p overexpression promoted cell viability, reduced apoptotic cell rate, arrested more cells in the S phase, and upregulated c-myc, cyclin E, and CDK2 expression. BLM was a target gene of miR-522-3p, and miR-522-3p suppression did not exert antiproliferative and proapoptotic activities when BLM was silenced. These findings demonstrate that miR-522-3p upregulation negatively regulates the expression of BLM, with upregulation of c-myc, CDK2, and cyclin E, and thereby promoting the proliferation of human CRC cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-522"}
{"PMID":26045793,"Year":2015,"Title":"The potential value of miR-1 and miR-374b as biomarkers for colorectal cancer.","Abstract":"The mortality of colorectal cancer (CRC) is growing due to the unsatisfactory specificity and sensitivity of the existing screening methods. Previous studies have focused on the role of miRNAs as CRC biomarkers. However, few studies have examined the miRNA profiles at each stage. The objective of this study was to identify miRNAs that distinguish CRC patients from normal people to prevent the misdiagnosis of patients with certain stages of CRC. We performed miRNA profiling of 1547 human miRNAs by qRT-PCR in CRC patients with stage II and stage III disease. The statistical analyses showed that there were 96 miRNAs that were significantly dysregulated in CRC relative to normal tissues (P<0.05). There were 28 dysregulated miRNAs associated with separate or combined stages II and III disease. There were 25 downregulated miRNAs, including the following: miR-1, -145, -145*, -137, -363, -143, -4770, -490-5p, -9, -144*, -99a, -99b, -23b, -143*, -100, -768-3p, -24-1*, -125a-5p, -30e*, -574-3p, -126, let-7b, miR-1979, -374b, and -140-3p. We found an upregulation of miR-203, 182, and 96. Our results demonstrated that the expression of miR-1 and miR-374b was significantly decreased in each stage and may function as a biomarker of CRC. Furthermore, 20 miRNAs were dysregulated both in stage II disease without lymph node or distant metastasis and in stage II-III tumors but not in stage III tumors. Only miR-4794 was involved exclusively with stage II tumors, and there were 19 miRNAs that were dysregulated only in stage III disease with lymph node metastasis and in stage II-III disease. There were only 6 miRNAs that were uniquely dysregulated in stage III. Our results indicate that miRNA expression may be valuable in the clinic. However, large prospective studies are required to confirm the role of miRNAs. This study provides a new model for analyzing novel CRC biomarkers by considering more clinical factors.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-203"}
{"PMID":24445140,"Year":2014,"Title":"MicroRNA-451 suppresses tumor cell growth by down-regulating IL6R gene expression.","Abstract":"The miR-451 was found to be frequently down-regulated in tumors, indicating that miR-451 could play an important role in carcinogenesis. This study uncovered the mechanism by which the miR-451 functions as a tumor suppressor. The target genes of miR-451 were determined using target gene prediction softwares. Then the miR-451 mimics were introduced into RKO and Hela cells respectively. The proliferation and invasion of cells were monitored by MTT, cell cycle and in vitro extracellular matrix invasion assays. Also the angiogenesis of HUVEC cells transfected with miR-451 mimics was examined. Subsequently, IL6R, a predicted target gene of miR-451, was studied by real time PCR, Western blotting, and siRNA technologies. The mRNA and protein levels of IL6R gene were found to be down-regulated in the RKO and Hela cells transfected with miR-451 mimics. Consequently, the cell proliferation was inhibited. Also, the invasion of RKO cells was suppressed. Furthermore, the angiogenesis of HUVEC cells transfected with miR-451 mimics was assayed and the decreased angiogenic ability was detected compared to the controls. All these results were validated by IL6R siRNA experiments. The IL6R gene is a target gene of miR-451. The miR-451 behaves as a tumor suppressor, probably by targeting the IL6R pathway.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-451"}
{"PMID":19391107,"Year":2009,"Title":"Mechanism of growth inhibition by MicroRNA 145: the role of the IGF-I receptor signaling pathway.","Abstract":"MicroRNA 145 (miR145) has been proposed as a tumor suppressor. It was previously shown that miR145 targets the 3' UTR of the insulin receptor substrate-1 (IRS-1) and dramatically inhibits the growth of colon cancer cells. miR145 also targets the type 1 insulin-like growth factor receptor (IGF-IR). We show here that an IRS-1 lacking its 3' UTR is no longer down-regulated by miR145 and rescues colon cancer cells from miR145-induced inhibition of growth. An IGF-IR resistant to miR145 (again by elimination of its 3' UTR) is not down-regulated by miR145 but fails to rescue colon cancer cells from growth inhibition. These and other results, taken together, indicate that down-regulation of IRS-1 plays a significant role in the tumor suppressor activity of miR145.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":23950216,"Year":2013,"Title":"Fecal miR-106a is a useful marker for colorectal cancer patients with false-negative results in immunochemical fecal occult blood test.","Abstract":"BACKGROUND: Immunochemical fecal occult blood test (iFOBT) is widely used for colorectal cancer screening; however, its sensitivity is insufficient. We recently reported a fecal microRNA (miRNA) test (FmiRT) to detect colorectal cancer. In this study, we investigated a new colorectal cancer screening method combining iFOBT and FmiRT to improve the sensitivity compared with iFOBT alone. METHODS: In total, 117 colorectal cancer patients and 107 healthy volunteers were enrolled. Ten-milligram fecal samples were collected and iFOBT was conducted. Fecal RNA was extracted from residuum of iFOBT and then the expression of 14 kinds of miRNA was analyzed for the FmiRT using real-time reverse transcription PCR. RESULTS: Levels of fecal miR-106a expression in iFOBT+ patients and iFOBT- patients were significantly higher than in healthy volunteers (P = 0.001). The sensitivity and specificity of FmiRT using miR-106a were 34.2% and 97.2%, and those of iFOBT were 60.7% and 98.1%, respectively. The overall sensitivity and specificity of the new screening method combining iFOBT and FmiRT were 70.9% and 96.3%, respectively. One quarter of colorectal cancer patients with false-negative iFOBT seemed to be true positive upon adding FmiRT using fecal miR-106a. CONCLUSIONS: Fecal miR-106a is a good molecular marker to identify colorectal cancer patients from among those with negative iFOBT results. FmiRT combined with iFOBT may improve the sensitivity to detect colorectal cancer. IMPACT: We have shown the usefulness of fecal miR-106a to detect the colorectal cancer patients among those with negative iFOBT results.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-106"}
{"PMID":23690963,"Year":2013,"Title":"Identification and evaluation of plasma microRNAs for early detection of colorectal cancer.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the most commonly diagnosed cancers. Circulating microRNAs (miRNAs) have been suggested as potentially promising markers for early detection of CRC. We aimed to identify and evaluate a panel of miRNAs that might be suitable for CRC early detection. METHODS: MiRNAs were profiled by TaqMan MicroRNA Array and screened for differential expression in 5 pools of plasma samples of CRC patients (N = 50) and 5 pools of neoplasm-free controls (N = 50). Additional miRNAs were selected from a literature review. Identified candidates were evaluated in independent validation samples with respect to discrimination of CRC patients (N = 80) or advanced adenoma patients (N = 50) and neoplasm-free controls (N = 194). Diagnostic performance of the panel of miRNAs was assessed by multiple logistic regression, using bootstrap analysis to correct for over-optimism. RESULTS: Five miRNAs identified to be differentially expressed from TaqMan MicroRNA Array (miR-29a, -106b, -133a, -342-3p, -532-3p), and seven miRNAs reported to be differentially expressed in the literature (miR-18a, -20a, -21, -92a, -143, -145, -181b) were selected for validation. Nine of the twelve miRNAs (miR-18a, -20a, -21, -29a, -92a, -106b, -133a, -143, -145) were found to be differentially expressed in CRC patients and controls in the validation samples. The optimism-corrected area under the curve was 0.745 (95% confidence interval: 0.708-0.846). None of the selected miRNAs showed significant differential expression between advanced adenoma patients and neoplasm-free controls. CONCLUSION: The identified panel of miRNAs could be of potential use in the development of a multi-marker blood based test for early detection of CRC. IMPACT: The study underscores the high potential of plasma miRNAs for the improvement of current offers of non-invasive CRC screening.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-20"}
{"PMID":25781635,"Year":2015,"Title":"Canolol inhibits gastric tumors initiation and progression through COX-2/PGE2 pathway in K19-C2mE transgenic mice.","Abstract":"4-Vinyl-2, 6-dimethoxyphenol (canolol) is an antioxidant phenolic compound extracted from crude canola oil. In current research, K19-C2mE transgenic mice, developing hyperplastic tumors spontaneously in the glandular stomach, were used to study the mechanisms involved in the anti-inflammation and anti-tumor effects of canolol. Tg mice receiving canolol diet had a reduced tumor incidence, to 41.2%, compared with Non-treatment Tg mice, 77.8% of which had gastric tumor (P=0.002). Besides that, the mean tumor diameter was decreased from 6.5 mm to 4.5 mm (P<0.001) after canolol administration. COX-2/PGE2 pathway is known to play pivotal role in inflammation-induced gastric tumorigenesis. The neutrophils and lymphocytes infiltration was suppressed significantly, and the mRNA levels of the proinflammatory cytokines COX-2, IL-1beta and IL-12b were also downregulated in gastric mucosa. Additionally, immunohistochemical analysis showed that COX-2, EP2, Galphas and beta-catenin, key factors involving in PGE2 signal transduction, were positive staining with higher H scores in Non-treatment Tg mice, while the expressions were suppressed significantly by 0.1% canolol (P<0.001). In addition, tumor-suppressor miR-7 was reactivated after canolol administration, and COX-2 was showed to be a functional target of miR-7 to suppress the tumor progression. In conclusion, canolol could inhibit the gastritis-related tumor initiation and progression, and the suppression effect was correlated with the blocking up of canonical COX-2/PGE2 signaling pathway and might be regulated by miR-7.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-7"}
{"PMID":20044760,"Year":2010,"Title":"Prognostic impact of microRNA-related gene polymorphisms on survival of patients with colorectal cancer.","Abstract":"PURPOSE: The polymorphisms in microRNA (miRNA) machinery genes and miRNA-containing genomic regions may play an important role in cancer development and prognosis. Accordingly, the present study analyzed the single nucleotide polymorphisms (SNPs) of miRNA-related genes and their impact on the prognosis for patients with colorectal cancer. METHODS: Four hundred and twenty-six consecutive patients with surgically treated colorectal adenocarcinoma were enrolled. The genomic DNA was extracted from fresh colorectal tissue and 40 polymorphisms of miRNA-related genes determined using a real-time PCR genotyping assay. RESULTS: In a univariate analysis, the progression-free survival of the patients with the combined mir492 C/G and G/G genotype was significantly worse than that of the patients with the mir492 C/C genotype (rs2289030) (P value = 0.0426), although there was no difference in the overall survival. However, no association was noted between the SNPs of the miRNA-related genes evaluated and survival in a multivariate analysis. CONCLUSIONS: None of the 40 miRNA-related gene polymorphisms investigated in this study was found to be an independent prognostic marker for Korean patients with surgically resected colorectal cancer. However, further studies are warranted to clarify the role of miRNA-related gene polymorphisms as a prognostic biomarker for colorectal cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-492"}
{"PMID":31073530,"Year":2019,"Title":"miRNA and mRNA Integration Network Construction Reveals Novel Key Regulators in Left-Sided and Right-Sided Colon Adenocarcinoma.","Abstract":"Background: The distinction between right-sided and left-sided colon adenocarcinoma has recently received considerable. This study aims to identify key MicroRNA (miRNA) and mRNAs in right-sided colon adenocarcinoma (RSCOAD) and left-sided colon adenocarcinoma (LSCOAD) by TCGA integration analysis. Methods: The miRNA and mRNA expression profiles of a large group of patients with RSCOAD and LSCOAD were obtained from TCGA. The differentially expressed miRNAs (DEmiRNAs) and mRNAs (DEmRNAs) were identified by TCGA integration analysis. The optimal diagnostic miRNA biomarkers for RSCOAD and LSCOAD were identified by Boruta algorithm. We established classification models to distinguish RSCOAD and LSCOAD. Protein-protein interaction (PPI) network analysis, DEmiRNA-DEmRNA interaction analysis, and functional annotation were performed. The expression of selected DEmiRNAs and DEmRNAs was validated by qRT-PCR. Results: A total of 2534 DEmRNAs (940 downregulated and 1594 upregulated mRNAs) and 54 DEmiRNAs (22 downregulated and 32 upregulated miRNAs) between RSCOAD and LSCOAD were identified. The feature selection procedure was to obtain 22 optimal diagnostic miRNAs biomarkers in RSCOAD compared to LSCOAD. The AUC of the random forests model was 0.869 and the specificity and sensitivity of this model were 79% and 84.6%, respectively. Three DEmiRNAs (hsa-miR-224-5p, hsa-miR-155-5p, and hsa-miR-31-5p) and five DEmRNAs (CXCR4, SMAD4, KRAS, FITM2, and PLAGL2) were identified key DEmiRNAs and DEmRNAs in RSCOAD compared to LSCOAD. The qRT-PCR results of CXCR4, FITM2, TFAP2A, ULBP2, hsa-miR-224-5p, and hsa-miR-155-5p were consistent with our integrated analysis. Conclusion: A total of three DEmiRNAs (hsa-miR-224-5p, hsa-miR-155-5p, and hsa-miR-31-5p) and five DEmRNAs (CXCR4, SMAD4, KRAS, FITM2, and PLAGL2) may be involved in the pathogenesis of RSCOAD and LSCOAD which may make a contribution for understanding mechanisms and developing therapeutic strategies for RSCOAD and LSCOAD.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-224"}
{"PMID":19520829,"Year":2009,"Title":"Dicer-regulated microRNAs 222 and 339 promote resistance of cancer cells to cytotoxic T-lymphocytes by down-regulation of ICAM-1.","Abstract":"The RNase III endonuclease Dicer plays a key role in generation of microRNAs (miRs). We hypothesized that Dicer regulates cancer cell susceptibility to immune surveillance through miR processing. Indeed, Dicer disruption up-regulated intercellular cell adhesion molecule (ICAM)-1 and enhanced the susceptibility of tumor cells to antigen-specific lysis by cytotoxic T-lymphocytes (CTLs), while expression of other immunoregulatory proteins examined was not affected. Blockade of ICAM-1 inhibited the specific lysis of CTLs against Dicer-disrupted cells, indicating a pivotal role of ICAM-1 in the interaction between tumor cells and CTL. Both miR-222 and -339 are down-regulated in Dicer-disrupted cells and directly interacted with the 3' untranslated region (UTR) of ICAM-1 mRNA. Modulation of Dicer or these miRs inversely correlated with ICAM-1 protein expression and susceptibility of U87 glioma cells to CTL-mediated cytolysis while ICAM-1 mRNA levels remained stable. Immunohistochemical and in situ hybridization analyses of 30 primary glioblastoma tissues demonstrated that expression of Dicer, miR-222, or miR-339 was inversely associated with ICAM-1 expression. Taken together, Dicer is responsible for the generation of the mature miR-222 and -339, which suppress ICAM-1 expression on tumor cells, thereby down-regulating the susceptibility of tumor cells to CTL-mediated cytolysis. This study suggests development of novel miR-targeted therapy to promote cytolysis of tumor cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-339"}
{"PMID":23098991,"Year":2012,"Title":"MicroRNA profiling predicts survival in anti-EGFR treated chemorefractory metastatic colorectal cancer patients with wild-type KRAS and BRAF.","Abstract":"Anti-EGFR monoclonal antibodies (anti-EGFRmAb) serve in the treatment of metastatic colorectal cancer (mCRC), but patients with a mutation in KRAS/BRAF and nearly one-half of those without the mutation fail to respond. We performed microRNA (miRNA) analysis to find miRNAs predicting anti-EGFRmAb efficacy. Of the 99 mCRC patients, we studied differential miRNA expression by microarrays from primary tumors of 33 patients who had wild-type KRAS/BRAF and third- to sixth-line anti-EGFRmAb treatment, with/without irinotecan. We tested the association of each miRNA with overall survival (OS) by the Cox proportional hazards regression model. Significant miR-31* up-regulation and miR-592 down-regulation appeared in progressive disease versus disease control. miR-31* expression and down-regulation of its target genes SLC26A3 and ATN1 were verified by quantitative reverse transcriptase polymerase chain reaction. Clustering of patients based on miRNA expression revealed a significant difference in OS between patient clusters. Members of the let-7 family showed significant up-regulation in the patient cluster with poor OS. Additionally, miR-140-5p up-regulation and miR-1224-5p down-regulation were significantly associated with poor OS in both cluster analysis and the Cox proportional hazards regression model. In mCRC patients with wild-type KRAS/BRAF, miRNA profiling can efficiently predict the benefits of anti-EGFRmAb treatment. Larger series of patients are necessary for application of these miRNAs as predictive/prognostic markers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-140"}
{"PMID":22235338,"Year":2012,"Title":"MicroRNA-211 expression promotes colorectal cancer cell growth in vitro and in vivo by targeting tumor suppressor CHD5.","Abstract":"BACKGROUND: Chromodomain-helicase-DNA-binding protein 5 (CHD5) is a newly identified tumor suppressor that is frequently downregulated in a variety of human cancers. Our previous work revealed that the low expression of CHD5 in colorectal cancer is correlated with CHD5 promoter CpG island hypermethylation. In this study, we investigated the effect of microRNA-211 (miR-211)-regulated CHD5 expression on colorectal tumorigenesis. METHODOLOGY/PRINCIPAL FINDINGS: miR-211 was predicted to target CHD5 by TargetScan software analysis. A stably expressing exogenous miR-211 colorectal cancer cell line (HCT-116(miR-211)) was generated using lentiviral transduction and used as a model for in vitro and in vivo studies. The expression level of miR-211 in HCT-116(miR-211) cells was upregulated by 16-fold compared to vector control cells (HCT-116(vector)). Exogenous miR-211 directly binds to the 3'-untranslated region (3'-UTR) of CHD5 mRNA, resulting in a 50% decrease in CHD5 protein level in HCT-116(miR-211) cells. The levels of cell proliferation, tumor growth, and cell migration of HCT-116(miR-211) cells were significantly higher than HCT-116(vector) cells under both in vitro and in vivo conditions, as determined using the methods of MTT, colony formation, flow cytometry, scratch assay, and tumor xenografts, respectively. In addition, we found that enforced expression of miR-211 in HCT-116 cells was able to alter p53 pathway-associated regulatory proteins, such as MDM2, Bcl-2, Bcl-xL, and Bax. CONCLUSION/SIGNIFICANCE: Our results demonstrate that CHD5 is a direct target of miR-211 regulation. Enforced expression of miR-211 promotes tumor cell growth at least in part by downregulating the expression level of the CHD5 tumor suppressor. Our results provide a better understanding of the association of between miR-211-regulated CHD5 expression and CHD5 function in colorectal tumorigenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-211"}
{"PMID":21532750,"Year":2011,"Title":"Differential expression of microRNAs in tumors from chronically inflamed or genetic (APC(Min/+)) models of colon cancer.","Abstract":"BACKGROUND: Chronic inflammation associated with ulcerative colitis predisposes individuals to increased colon cancer risk. The aim of these studies was to identify microRNAs that are aberrantly regulated during inflammation and may participate in transformation of colonic epithelial cells in the inflammatory setting. METHODOLOGY/PRINCIPAL FINDINGS: We have use quantitative PCR arrays to compare microRNA (miRNA) expression in tumors and control colonic epithelial cells isolated from distal colons of chronically inflamed mice and APC(Min/+) mice. Rank order statistics was utilized to identify differentially regulated miRNAs in tumors that arose due to chronic inflammation and/or to germline APC mutation. Eight high priority miRNAs were identified: miR-215, miR-137, miR-708, miR-31, and miR-135b were differentially expressed in APC tumors and miR-215, miR-133a, miR-467d, miR-218, miR-708, miR-31, and miR-135b in colitis-associated tumors. Four of these (miR-215, miR-708, miR-31, and miR-135b) were common to both tumors types, and dysregulation of these miRNAs was confirmed in an independent sample set. Target prediction and pathway analysis suggests that these microRNAs, in the aggregate, regulate signaling pathways related to MAPK, PI3K, WNT, and TGF-beta, all of which are known to be involved in transformation. CONCLUSIONS/SIGNIFICANCE: We conclude that these four miRNAs are dysregulated at some very early stage in transformation of colonic epithelial cells. This response is not dependent on the mechanism of initiation of transformation (inflammation versus germline mutation), suggesting that the miRNAs that we have identified are likely to regulate critical signaling pathways that are central to early events in transformation of colonic epithelial cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-135"}
{"PMID":29199088,"Year":2018,"Title":"A MicroRNA Signature Associated With Metastasis of T1 Colorectal Cancers to Lymph Nodes.","Abstract":"Most T1 colorectal cancers treated by radical surgery can now be cured by endoscopic submucosal dissection. Although 70%-80% of T1 colorectal cancers are classified as high risk, <16% of these patients actually have lymph node metastases. Biomarkers are needed to identify patients with T1 cancers with the highest risk of metastasis, to prevent unnecessary radical surgery. We collected data from The Cancer Genome Atlas and identified 5 microRNAs (MIR32, MIR181B, MIR193B, MIR195, and MIR411) with significant changes in expression in T1 and T2 colorectal cancers with vs without lymph node metastases. Levels of the 5 microRNAs identified patients with lymph node invasion by T1 or T2 cancers with an area under the receiver operating characteristic curve (AUROC) value of 0.84. We validated these findings in 2 cohorts of patients with T1 cancers, using findings from histology as the reference. The 5-microRNA signature identified T1 cancers with lymph node invasion in cohort 1 with an AUROC value of 0.83, and in cohort 2 with an AUROC value of 0.74. When we analyzed biopsy samples from untreated patients, the 5-microRNA signature identified cancers with lymph node metastases with an AUROC value of 0.77. The 5-microRNA therefore identifies high-risk T1 colorectal cancers with a greater degree of accuracy than currently used pathologic features.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-195"}
{"PMID":24399071,"Year":2014,"Title":"Effects of common polymorphisms rs2910164 in miR-146a and rs11614913 in miR-196a2 on susceptibility to colorectal cancer: a systematic review meta-analysis.","Abstract":"PURPOSE: Emerging evidence has shown that single nucleotide polymorphisms occurred in microRNAs may contribute to the development of colorectal cancer (CRC). rs2910164 in miR-146a and rs11614913 in miR-196a2 are suggested to be associated with the susceptibility to CRC, but individually published studies revealed inconclusive results. To systematically summarize the possible correlationship between these polymorphisms and CRC risk, we performed this meta-analysis. METHODS: We retrieved the relevant articles of the associations between these two microRNA polymorphisms and susceptibility to CRC for the period up to July 1, 2013. A total of seven articles were identified with 2,143 cases and 2,457 controls for miR-146a rs2910164, 1,594 cases and 2,252 controls for miR-196a2 rs11614913. Odds ratio and 95 % confidence interval were calculated to investigate the strength of the association. RESULTS: The pooled analysis showed that miR-146a rs2910164 did not reveal any correlation with CRC susceptibility. However, a decreased risk was observed between miR-196a2 rs11614913 and CRC in all genetic models. CONCLUSION: Our current meta-analysis demonstrates that miR-196a2 rs11614913 most likely contributes to decreased risk of CRC, whereas miR-146a rs2910164 may not be associated with the susceptibility to CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-146"}
{"PMID":27881005,"Year":2017,"Title":"A microRNA expression signature as a predictor of survival for colon adenocarcinoma.","Abstract":"Colon cancer is a major cause of cancer mortality worldwide and most colon cancers are adenocarcinoma. MicroRNA (miRNA) expression signature has been shown to be able to predict progression and prognosis of various cancers. The aim of our study was to explore a novel signature of microRNA expression for predicting survival of colon adenocarcinoma patients. By analyzing the miRNA expression profiles and clinical information of 329 colon adenocarcinoma patients derived from The Cancer Genome Atlas database. 129 miRNAs were identified to be expressed differentially between the cancer and adjacent tissues. Among them, 27 miRNAs were found to be associated with the corresponding clinical characteristics of the patients. Furthermore, 7 miRNAs (let-7a-2, mir-32, mir-181a-1, mir-197, mir-328, mir-505 and mir-652) were found to be significantly correlated with the patient survival. The risk established by the 7-miRNA signature we built was proved be an independent prognostic factor (Hazard ratio [HR] = 2.048; 95% CI = 1.144-3.664; p, 0.016). In summary, our study identified miRNAs correlated with progression and prognosis of colon adenocarcinoma and built a 7-microRNA expression signature for prediction of the survival of the patients with colon adenocarcinoma.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7-"}
{"PMID":25371200,"Year":2014,"Title":"MicroRNA-200 (miR-200) cluster regulation by achaete scute-like 2 (Ascl2): impact on the epithelial-mesenchymal transition in colon cancer cells.","Abstract":"Ascl2, a basic helix-loop-helix transcription factor, is a downstream target of WNT signaling that controls the fate of intestinal cryptic stem cells and colon cancer progenitor cells. However, its involvement in colon cancer and downstream molecular events is largely undefined; in particular, the mechanism by which Ascl2 regulates the plasticity of epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) programs in colon cancer cells remains unknown. In this study, we systematically demonstrate that Ascl2 loss of function in colon cancer cells promotes MET by derepressing the expression of microRNA (miR)-200s (i.e. miR-200b, miR-200a, miR-429, miR-200c, and miR-141) and further activating their expression through a transcriptional mechanism that involves direct binding to the most proximal E-box (E-box2) in the miR-200b-a-429 promoter. Activation of miR-200s due to Ascl2 deficiency led to the inhibition of ZEB1/2 expression and the alteration of epithelial and mesenchymal features. Transfection of miR-200b, miR-200a, and miR-429 inhibitors into Ascl2-deficient colon cancer cells promoted the epithelial-mesenchymal transition in a reversible manner. Transfection of miR-200a or miR-429 inhibitors into Ascl2-deficient colon cancer cells increased cellular proliferation and migration. Ascl2 mRNA levels and the miR-200a, miR-200b, miR-200c, miR-141, or miR-429 levels in the colon cancerous samples were inversely correlated. These results provide the first evidence of a link between Ascl2 and miR-200s in the regulation of EMT-MET plasticity in colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-429"}
{"PMID":29748374,"Year":2018,"Title":"The miR-371 approximately 373 Cluster Represses Colon Cancer Initiation and Metastatic Colonization by Inhibiting the TGFBR2/ID1 Signaling Axis.","Abstract":"The vast majority of colorectal cancer-related deaths can be attributed to metastatic spreading of the disease. Therefore, deciphering molecular mechanisms of metastatic dissemination is a key prerequisite to improve future treatment options. With this aim, we took advantage of different colorectal cancer cell lines and recently established primary cultures enriched in colon cancer stem cells, also known as tumor-initiating cells (TIC), to identify genes and miRNAs with regulatory functions in colorectal cancer progression. We show here that metastasis-derived TICs display increased capacity for self-renewal, TGFbeta signaling activity, and reduced expression of the miR-371 approximately 373 cluster compared with nonmetastatic cultures. TGFbeta receptor 2 (TGFBR2) and aldehyde dehydrogenase A1 (ALDH1A1) were identified as important target genes of the miR-371 approximately 373 cluster. In addition, TGFBR2 repression, either by direct knockdown or indirectly via overexpression of the entire miR-371 approximately 373 cluster, decreased tumor-initiating potential of TICs. We observed significantly reduced in vitro self-renewal activity as well as lowered tumor initiation and metastatic outgrowth capacity in vivo following stable overexpression of the miR-371 approximately 373 cluster in different colon TIC cultures. Inhibitor of DNA binding 1 (ID1) was affected by both TGFBR2 and miR-371 approximately 373 cluster alterations. Functional sphere and tumor formation as well as metastatic dissemination assays validated the link between miR-371 approximately 373 and ID1. Altogether, our results establish the miR-371 approximately 373/TGFBR2/ID1 signaling axis as a novel regulatory mechanism of TIC self-renewal and metastatic colonization.Significance: These findings establish the miR-371 approximately 373/TGFBR2/ID1 signaling axis as a novel mechanism regulating self-renewal of tumor-initiating cell and metastatic colonization, potentially opening new concepts for therapeutic targeting of cancer metastasis.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/14/3793/F1.large.jpg Cancer Res; 78(14); 3793-808. (c)2018 AACR.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-371"}
{"PMID":29725503,"Year":2018,"Title":"miRNA involvement in cell cycle regulation in colorectal cancer cases.","Abstract":"Uncontrolled cell replication is a key component of carcinogenesis. MicroRNAs (miRNAs) regulate genes involved in checkpoints, DNA repair, and genes encoding for key proteins regulating the cell cycle. We investigated how miRNAs and mRNAs in colorectal cancer subjects interact to regulate the cell cycle. Using RNA-Seq data from 217 individuals, we analyzed differential expression (carcinoma minus normal mucosa) of 123 genes within the cell cycle pathway with differential miRNA expression, adjusting for age and sex. Multiple comparison adjustments for gene/miRNA associations were made at the gene level using an FDR <0.05. Differentially expressed miRNAs and mRNAs were tested for associations with colorectal cancer survival. MRNA and miRNA sequences were compared to identify seed region matches to support biological interpretation of the observed associations. Sixty-seven mRNAs were dysregulated with a fold change (FC) <0.67 or >1.50. Thirty-two mRNAs were associated with 48 miRNAs; 102 of 290 total associations had identified seed matches; of these, ten had negative beta coefficients. Hsa-miR-15a-5p and hsa-miR-20b-5p were associated with colorectal cancer survival with an FDR <0.05 (HR 0.86 95% CI 0.79, 0.94; HR 0.83 95% CI 0.75, 0.91 respectively). Our findings suggest that miRNAs impact mRNA translation at multiple levels within the cell cycle.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-15"}
{"PMID":28870889,"Year":2018,"Title":"miR-194 as predictive biomarker of responsiveness to neoadjuvant chemoradiotherapy in patients with locally advanced rectal adenocarcinoma.","Abstract":"AIMS: Curative surgery remains the primary form of treatment for locally advanced rectal cancer (LARC). Recent data support the use of preoperative chemoradiotherapy (pCRT) to improve the prognosis of LARC with a significant reduction of local relapse and an increase of overall survival. Unfortunately, only 20% of the patients with LARC present complete pathological response after pCRT, whereas in 20%-40%, the response is poor or absent. METHODS: We investigated the expression level of miR-194 in n=38 patients with LARC using our public microRNA (miRNA) expression dataset. miR-194 expression was further validated by real-time quantitative PCR (qRT-PCR) and in situ hybridisation (ISH). Protein-protein interaction network and pathway enrichment analysis were performed on miR-194 targets. RESULTS AND DISCUSSION: Using biopsy samples collected at diagnosis, mir-194 was significantly upregulated in patients responding to treatment (p value=0.016). The data was confirmed with qRT-PCR (p value=0.0587) and ISH (p value=0.026). Protein-protein interaction network and pathway enrichment analysis reveal a possible mechanism of susceptibility to pCRT involving Wnt pathway via its downstream mediator TRAF6. Finally, we interrogated the Comparative Toxicogenomics Database database in order to identify those chemical compounds able to mimic the biological effects of miR-194 as new possible therapeutic option in LARC treatment. The present study combining miRNA expression profiling with integrative computational biology identified miR-194 as predictive biomarker of response to pCRT. Using known and predicted drug mechanism of action, we then identified possible chemical compounds for further in vitro validation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-194"}
{"PMID":26215320,"Year":2015,"Title":"Calycosin induces apoptosis by the regulation of ERbeta/miR-17 signaling pathway in human colorectal cancer cells.","Abstract":"Prior studies have suggested that a high intake of isoflavonoids is associated with a protective effect against hormone-related cancers, such as colorectal cancer (CRC). Calycosin, a main component of isoflavones, has been shown to suppress the growth of hormone-dependent tumors through an ERbeta-mediated signaling pathway. However, the effects of calycosin on CRC remain unclear. In this study, we aimed to investigate the anti-tumor activities of calycosin on CRC and its potential mechanism. HCT-116 cells were treated with calycosin. Cell proliferation, apoptosis and invasiveness were measured by MTT assay, flow cytometry and transwell invasion assay, respectively. mRNA levels of ER beta (ERbeta) and miR-17 were quantified by real-time PCR. Protein expressions of ERbeta and phosphatase and tensin homolog deleted on chromosome ten (PTEN) were determined by western blotting. We found that calycosin significantly induced apoptosis, and inhibited proliferation and invasiveness of HCT-116 cells in a dose-dependent manner. In addition, ERbeta expression significantly increased in calycosin-treated HCT-116 cells, followed by a decrease of miR-17, and up-regulation of PTEN. Our results indicate that calycosin has an inhibitory effect on CRC, which might be obtained by ERbeta-mediated regulation of miR-17 and PTEN expression.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-17"}
{"PMID":28940804,"Year":2017,"Title":"Long non-coding RNA CRNDE sponges miR-384 to promote proliferation and metastasis of pancreatic cancer cells through upregulating IRS1.","Abstract":"OBJECTIVE: Colorectal neoplasia differentially expressed (CRNDE), a vital cancer-related long non-coding RNA (lncRNA), has been brought to reports for playing quintessential functions in the growth and progression of several human malignancies. Nevertheless, the expression as well as the functional mechanisms of CRNDE in pancreatic cancer is not known so for. This study aimed at investigating the biological and clinical importance of CRNDE in human pancreatic cancer. MATERIALS AND METHODS: The expression levels of CRNDE in pancreatic cancer tissues as well as cell lines were identified with the help of quantitative real-time PCR (qRT-PCR). Furthermore, the analysis of the relationship between CRNDE expression and clinicopathologic characteristics of patients with pancreatic cancer was also performed. Novel target of CRNDE was identified with the use of bioinformatics analysis and confirmed by a dual-luciferase reporter assay. Colorectal neoplasia differentially expressed was knocked down using siRNA in pancreatic cancer cells. Thereafter, cell proliferation, migration and invasion were examined. Tumour xenograft was created to explore the function of CRNDE in tumorigenesis in vivo. RESULTS: Upregulation of the expression of CRNDE was found in pancreatic cancer tissues as well as cell lines, in comparison with the adjacent non-tumour tissues and human pancreatic duct epithelial cells. High expression of CRNDE was correlated with poor clinicpathological characteristics and shorter overall survival. We identified miR-384 as a direct target for CRNDE. Moreover, the CRNDE knockdown considerably inhibited pancreatic cancer cell proliferation, migration and invasion not only in vitro but also in vivo. In addition, CRNDE positively regulated IRS1 expression through sponging miR-384. CONCLUSIONS: Colorectal neoplasia differentially expressed performed an oncogenic function in cell proliferation as well as metastasis of pancreatic cancer. Our results suggest that CRNDE is likely to serve as an efficient therapeutic approach in respect of pancreatic cancer treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-384"}
{"PMID":25355599,"Year":2015,"Title":"MicroRNA-455 inhibits proliferation and invasion of colorectal cancer by targeting RAF proto-oncogene serine/threonine-protein kinase.","Abstract":"Colorectal cancer (CRC, also known as colon cancer, rectal cancer, or bowel cancer) is the second leading cause of cancer mortality in the Western world. MicroRNAs (miRNAs) are a class of small (18-25 nucleotides long) noncoding RNAs with important posttranscriptional regulatory functions. miRNAs play important roles in various physiological and pathological processes including carcinogenesis in various solid cancers including CRC. In order to investigate the roles that miRNAs played in CRC, the expression of human miRNAs (in 20 normal adjacent tissue samples and 20 colon cancer samples) was examined in this study. miR-455, miR-484, and miR-101 were significantly downregulated in colon cancer samples. And overexpression of miR-455 significantly inhibited the proliferation and the invasion of SW480, but had no effect on apoptosis. PCR and Western blot showed that overexpression of miR-455 decreased protein expression of RAF proto-oncogene serine/threonine-protein kinase (RAF1) but had no effect on mRNA level. Luciferase assay indicated that miR-455 regulated RAF1 expression directly. Moreover, overexpression of RAF1 partially reversed the inhibitory effect of miR-455 on the growth and the invasion of SW480. The data indicated that miR-455 regulates the proliferation and invasion of colorectal cancer cells, at least in part, by downregulating RAF1, a direct target of miR-455. Collectively, our study demonstrated that miR-455-RAF1 may represent a new potential therapeutic target for colorectal carcinoma treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-484"}
{"PMID":19926638,"Year":2010,"Title":"Oncofetal H19-derived miR-675 regulates tumor suppressor RB in human colorectal cancer.","Abstract":"H19 is an imprinted oncofetal non-coding RNA recently shown to be the precursor of miR-675. The pathophysiological roles of H19 and its mature product miR-675 to carcinogenesis have, however, not been defined. By quantitative reverse transcription-polymerase chain reaction, both H19 and miR-675 were found to be upregulated in human colon cancer cell lines and primary human colorectal cancer (CRC) tissues compared with adjacent non-cancerous tissues. Subsequently, the tumor suppressor retinoblastoma (RB) was confirmed to be a direct target of miR-675 as the microRNA suppressed the activity of the luciferase reporter carrying the 3'-untranslated region of RB messenger RNA that contains the miR-675-binding site. Suppression of miR-675 by transfection with anti-miR-675 increased RB expression and at the same time, decreased cell growth and soft agar colony formation in human colon cancer cells. Reciprocally, enhanced miR-675 expression by transfection with miR-675 precursor decreased RB expression, increased tumor cell growth and soft agar colony formation. Moreover, the inverse relationship between the expressions of RB and H19/miR-675 was also revealed in human CRC tissues and colon cancer cell lines. Our findings demonstrate that H19-derived miR-675, through downregulation of its target RB, regulates the CRC development and thus may serve as a potential target for CRC therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-675"}
{"PMID":22989523,"Year":2013,"Title":"Genetic and epigenetic factors in regulation of microRNA in colorectal cancers.","Abstract":"Studies on miRNA profiling revealed that a large number of them are significantly deregulated in human cancers. The molecular mechanisms of this deregulation are not totally clarified, even if genetics and epigenetics are frequently involved. Single nucleotide polymorphisms (SNPs) are the most common type of genetic variation in the human genome. A SNP into miRNA gene might affect the transcription of primary miRNA, its processing and miRNA-mRNA interaction. We investigated the distribution of sequence variants of miR-146a, miR-196a2, miR-499 and miR-149 in colorectal cancer (CRC) and their effect on miRNA expression. Each variant was identified with HRM. For miR-499 we demonstrated a significant reduction of its expression in CRC connected to a specific genotype. To evaluate the epigenetic effects on miRNA genes in CRC, we investigated the influence of DNA methylation on miR-34b, miR-34c and miR-9-1 expression. We aimed to verify the relationship between the methylation status of these miRNA genes and their relative expression in tumor samples. For the quantification of DNA methylation we adopted a method based on Differential High Resolution Melting (D-HRM).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":30458288,"Year":2019,"Title":"A panel of seven-miRNA signature in plasma as potential biomarker for colorectal cancer diagnosis.","Abstract":"Colorectal cancer (CRC) has been one of the most commonly diagnosed cancers in global. The differential expression profiles of microRNAs (miRNAs) in CRC plasma of patients have the potential to serve as a diagnostic biomarker. We conducted a four-stage study to identify the potential plasma miRNAs for CRC detection. In the initial screening phase, Exiqon panel (miRCURY-Ready-to-Use-PCR-Human-panel-I+II-V1.M) including 3 CRC pools and 1 normal controls (NCs) pool were applied to acquire miRNA profiles. In the training stage (30 CRC VS. 30 NCs) and testing stage (79 CRC VS. 76 NCs), quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to conduct candidate miRNA profiles. Then the identified miRNAs were verified in external validation stage (30 CRC VS. 26 NCs). Expression levels of identified miRNAs were assessed in tissue samples (24 pairs) and plasma exosomes (18 CRC VS. 18 NCs). Receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic accuracy. Seven miRNAs (miR-103a-3p, miR-127-3p, miR-151a-5p, miR-17-5p, miR-181a-5p, miR-18a-5p and miR-18b-5p) were significantly overexpressed in CRC compared with NCs. Area under the ROC curve of the seven-miRNA signature was 0.762, 0.824 and 0.895 for the training, testing and the external validation stages, respectively. Additionally, miR-103a-3p, miR-127-3p, miR-17-5p and miR-18a-5p were discovered significantly up-regulated in CRC tissues; while miR-17-5p, miR-181a-5p, miR-18a-5p and miR-18b-5p were significantly elevated in CRC plasma exosomes. In conclusion, we established a seven-miRNA signature in the peripheral plasma for CRC detection.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-151"}
{"PMID":24278149,"Year":2013,"Title":"Association between microRNA polymorphisms and cancer risk based on the findings of 66 case-control studies.","Abstract":"MicroRNAs (miRNAs) are small non-coding RNA molecules, which participate in diverse biological processes and may regulate tumor suppressor genes or oncogenes. Single nucleotide polymorphisms (SNPs) in miRNA may contribute to diverse functional consequences, including cancer development, by altering miRNA expression. Numerous studies have shown the association between miRNA SNPs and cancer risk; however, the results are generally debatable and inconclusive, mainly due to limited statistical power. To assess the relationship between the five most common SNPs (miR-146a rs2910164, miR-196a2 rs11614913, miR-499 rs3746444, miR-149 rs2292832, and miR-27a rs895919) and the risk cancer development, we performed a meta-analysis of 66 published case-control studies. Crude odds ratios at 95% confidence intervals were used to investigate the strength of the association. No association was observed between rs2910164 and cancer risk in the overall group. However, in stratified analysis, we found that either the rs2910164 C allele or the CC genotype was protective against bladder cancer, prostate cancer, cervical cancer, and colorectal cancer, whereas it was a risk factor for papillary thyroid carcinoma and squamous cell carcinoma of the head and neck (SCCHN). Further, rs11614913 was found to be significantly associated with decreased cancer risk, in particular, for bladder cancer, gastric cancer, and SCCHN. For miR-499, a significant association was found between the rs3746444 polymorphism and cancer risk in pooled analysis. In subgroup analysis, similar results were mainly observed for breast cancer. Finally, no association was found between rs2292832 and rs895919 polymorphisms and cancer risk in the overall group and in stratified analysis. In summary, miR-196a2 rs11614913, miR-146a rs2910164, and miR-499 rs3746444 are risk factors for cancer development, whereas mir-149 rs2292832 and miR-27a rs895919 are not associated with cancer risk.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":21694772,"Year":2011,"Title":"miRNA expression in colon polyps provides evidence for a multihit model of colon cancer.","Abstract":"Changes in miRNA expression are a common feature in colon cancer. Those changes occurring in the transition from normal to adenoma and from adenoma to carcinoma, however, have not been well defined. Additionally, miRNA changes among tumor subgroups of colon cancer have also not been adequately evaluated. In this study, we examined the global miRNA expression in 315 samples that included 52 normal colonic mucosa, 41 tubulovillous adenomas, 158 adenocarcinomas with proficient DNA mismatch repair (pMMR) selected for stage and age of onset, and 64 adenocarcinomas with defective DNA mismatch repair (dMMR) selected for sporadic (n = 53) and inherited colon cancer (n = 11). Sporadic dMMR tumors all had MLH1 inactivation due to promoter hypermethylation. Unsupervised PCA and cluster analysis demonstrated that normal colon tissue, adenomas, pMMR carcinomas and dMMR carcinomas were all clearly discernable. The majority of miRNAs that were differentially expressed between normal and polyp were also differentially expressed with a similar magnitude in the comparison of normal to both the pMMR and dMMR tumor groups, suggesting a stepwise progression for transformation from normal colon to carcinoma. Among the miRNAs demonstrating the largest fold up- or down-regulated changes (>/=4), four novel (miR-31, miR-1, miR-9 and miR-99a) and two previously reported (miR-137 and miR-135b) miRNAs were identified in the normal/adenoma comparison. All but one of these (miR-99a) demonstrated similar expression differences in the two normal/carcinoma comparisons, suggesting that these early tumor changes are important in both the pMMR- and dMMR-derived cancers. The comparison between pMMR and dMMR tumors identified four miRNAs (miR-31, miR-552, miR-592 and miR-224) with statistically significant expression differences (>/=2-fold change).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-99"}
{"PMID":31560680,"Year":2019,"Title":"Novel Multiple miRNA-Based Signatures for Predicting Overall Survival and Recurrence-Free Survival of Colorectal Cancer Patients.","Abstract":"BACKGROUND Colorectal cancer (CRC) has become a heavy health burden around the world, accounting for about 10% of newly diagnosed cancer cases. In the present study, we aimed to establish the miRNA-based prediction signature to assess the prognosis of CRC patients. MATERIAL AND METHODS A total of 451 CRC patients' expression profiles and clinical information were download from the TCGA database. LASSO Cox regression was conducted to construct the overall survival (OS)- and recurrence-free survival (RFS)-associated prediction signatures, by which CRC patients were divided into low- and high-risk groups. Kaplan-Meier (K-M) curve and receiver operating characteristic (ROC) curves were used to explore the discriminatory ability and stability of the signatures. Functional enrichment analyses were performed to identify the probable mechanisms. RESULTS miRNA-216a, miRNA-887, miRNA-376b, and miRNA-891a were used to build the prediction formula associated with OS, while miR-1343, miR-149, miR-181a-1, miR-217, miR-3130-1, miR-378a, miR-542, miR-6716, miR-7-3, miR-7702, miR-677, and miR-891a were obtained to construct the formula related to RFS. K-M curve and ROC curve revealed the good discrimination and efficiency of OS in the training (P<0.001, AUC=0.712) and validation cohorts (P=0.019, AUC=0.657), as well as the results of RFS in the training (P<0.001, AUC=0.714) and validation cohorts (P=0.042, AUC=0.651). The function annotations for the targeted genes of these miRNAs show the potential mechanisms of CRC. CONCLUSIONS We established 2 novel miRNA-based prediction signatures of OS and RFS, which are reliable tools to assess the prognosis of CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-378"}
{"PMID":23055106,"Year":2013,"Title":"Isolation and characterization of calcium sensing receptor null cells: a highly malignant and drug resistant phenotype of colon cancer.","Abstract":"The expression of calcium sensing receptor (CaSR) in the human colonic crypt epithelium is linked to cellular differentiation while its lack of expression is associated with undifferentiated and invasive colon carcinoma. Human colon carcinoma cell lines contain small subpopulations (10-20%) that do not express CaSR (termed CaSR null cells). Here, we report on the isolation, propagation, maintenance and characterization of CaSR null cells from the CBS and HCT116 human colon carcinoma cell lines. CaSR null cells grew as three-dimensional non-adherent spherical clusters with increased propensity for anchorage independent growth, cellular proliferation and invasion of matrigels. CaSR null cells were highly resistant to fluorouracil and expressed abundant amount of thymidylate synthase and survivin. Molecular profiling by real time reverse transcription-polymerase chain reaction (RT-PCR) and Western blots showed a high level of expression of the previously reported cancer stem cell markers CD133, CD44 and Nanog in CaSR null cells. A significant increase in the expression of epithelial-mesenchymal transitional molecules and transcription factors was also observed. These include N-cadherin, beta-catenin, vimentin, fibronectin, Snail1, Snail2, Twist and FOXC2. The expression of the tumor suppressive E-cadherin and miR145, on the other hand, was greatly reduced while expression of the oncogenic microRNAs: miR21, miR135a and miR135b was significantly up-regulated. CaSR null cells possess a myriad of cellular and molecular features that drive and sustain the malignant phenotype. We conclude that CaSR null constitutes a highly malignant and drug resistant phenotype of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":30807603,"Year":2019,"Title":"Development of novel predictive miRNA/target gene pathways for colorectal cancer distance metastasis to the liver using a bioinformatic approach.","Abstract":"BACKGROUND: Liver metastases are the major cause of colorectal cancer (CRC)-related deaths. However, there is no reliable clinical predictor for CRC progression to liver metastasis. In this study, we investigated possible predictors (miRNAs and biomarkers) for clinical application. METHODOLOGY: The Gene Expression Omnibus (GEO) datasets GSE49355, GSE41258 and GSE81558 for genes and GSE54088 and GSE56350 for miRNAs were used to identify common differentially expressed genes (DEGs) and miRNAs between primary CRC tissues and liver metastases. The identified miRNAs and their targets from the DEGs were verified in datasets comprising gene, miRNA and miRNA exosome profiles of CRC patients with no distant metastases (M0) and distant metastases (M1); the interaction networks and pathways were also mapped. RESULTS: There were 49 upregulated and 13 downregulated DEGs and 16 downregulated and 14 upregulated miRNAs; between the DEGs and miRNA targets, there were five upregulated and four downregulated genes. MiR-20a was strongly correlated with the status of liver metastasis. MiR-20a, miR499a, and miR-576-5p were highly correlated with the metastatic outcomes. MiR-20a was significantly highly expressed in the M1 group. In an analysis of the miRNA target genes, we found that CDH2, KNG1, and MMP2 were correlated with CRC metastasis. We demonstrated a new possible pathway for CRC metastasis: miR-576-5p/F9, miR20a/MMP2, CTSK, MMP3, and miR449a/P2RY14. The regulation of IGF transport and uptake by IGFBPs, extracellular matrix organization, signal transduction and the immune system were the enriched pathways. CONCLUSION: This model can predict CRC to liver metastases and the pathways involved, which can be clinically applicable.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-20"}
{"PMID":27775664,"Year":2016,"Title":"A Comprehensive MicroRNA Expression Profile of Liver and Lung Metastases of Colorectal Cancer with Their Corresponding Host Tissue and Its Prognostic Impact on Survival.","Abstract":"MicroRNAs are small non-coding RNAs with a length of 18-25 nucleotides. They can regulate tumor invasion and metastasis by changing the expression and translation of their target mRNAs. Their expression is substantially altered in colorectal cancer cells as well as in the adjacent tumor-associated stroma. Both of these compartments have a mutual influence on tumor progression. In the development of metastases, cancer cells initially interact with the host tissue. Therefore, compartment-specific expression signatures of these three locations-tumor, associated stroma, and host tissue-can provide new insights into the complex tumor biology of colorectal cancer. Frozen tissue samples of colorectal liver (n = 25) and lung metastases (n = 24) were laser microdissected to separate tumor cells and the adjacent tumor-associated stroma cells. Additionally, normal lung and liver tissue was collected from the same patients. We performed a microarray analysis in four randomly selected liver metastases and four randomly selected lung metastases, analyzing a total of 939 human miRNAs. miRNAs with a significant change >2-fold between the tumor, tumor stroma, and host tissue were analyzed in all samples using RT-qPCR (11 miRNAs) and correlated with the clinical data. We found a differential expression of several miRNAs between the tumor, the tumor-associated stroma, and the host tissue compartment. When comparing liver and lung metastases, miR-194 showed a 1.5-fold; miR-125, miR-127, and miR-192 showed a 2.5-fold; miR-19 and miR-215 a 3-fold; miR-145, miR-199-3, and miR-429 a 5-fold; miR-21 a 7-fold; and, finally, miR-199-5 a 12.5-fold downregulation in liver metastases compared to lung metastases. Furthermore miR-19, miR-125, miR-127, miR-192, miR-194, miR-199-5, and miR-215 showed a significant upregulation in the normal liver tissue compared to the normal lung tissue. Univariate analysis identified an association of poor survival with the expression of miR-125 (p = 0.05), miR-127 (p = 0.001), miR-145 (p = 0.005), miR-192 (p = 0.015), miR-194 (0.003), miR-199-5 (p = 0.008), miR-215 (p < 0.001), and miR-429 (p = 0.03) in the host liver tissue of the liver metastases. Colorectal liver and lung metastases have a unique miRNA expression profile. miRNA expression in the host tissue of colorectal liver metastases seems to be able to influence tumor progression and survival. These findings can be used in the development of tailored therapies.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-19"}
{"PMID":29589310,"Year":2018,"Title":"RT-qPCR for Fecal Mature MicroRNA Quantification and Validation.","Abstract":"By routinely and systematically being able to perform quantitative stem-loop reverse transcriptase (RT) followed by TaqMan(R) minor-groove binding (MGB) probe, real-time quantitative PCR analysis on exfoliated enriched colonocytes in stool, using human (Homo sapiens, hsa) micro(mi)RNAs to monitor changes of their expression at various stages of colorectal (CRC) progression, this method allows for the reliable and quantitative diagnostic screening of colon cancer (CC). Although the expression of some miRNA genes tested in tissue shows less variability in normal or cancerous patients than in stool, the noninvasive stool by itself is well suited for CC screening. An miRNA approach using stool promises to offer more sensitivity and specificity than currently used genomic, methylomic, or proteomic methods for CC screening.To present an application of employing miRNAs as diagnostic markers for CC screening, we carried out global microarray expression studies on stool colonocytes isolated by paramagnetic beads, using Affymetrix GeneChip miRNA 3.0 Array, to select a panel of miRNAs for subsequent focused semiquantitative PCR analysis studies. We then conducted a stem-loop RT-TaqMan(R) MGB probes, followed by a modified real-time qPCR expression study on 20 selected miRNAs for subsequent validation of the extracted immunocaptured total small RNA isolated from stool colonocytes. Results showed 12 miRNAs (miR-7, miR-17, miR-20a, miR-21, miR-92a, miR-96, miR-106a, miR-134, miR-183, miR-196a, miR-199a-3p, and miR214) to have an increased expression in stool of CC patients, and that later TNM stages exhibited more increased expressions than adenomas, while 8 miRNAs (miR-9, miR-29b, miR-127-5p, miR-138, miR-143, miR-146a, miR-222, and miR-938) showed decreased expressions in stool of CC patients, which becomes more pronounced as the cancer progresses from early to late TNM stages (0-IV).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-196"}
{"PMID":19593777,"Year":2009,"Title":"MicroRNA expression profiling of human metastatic cancers identifies cancer gene targets.","Abstract":"Small non-coding microRNAs (miRNAs) contribute to cancer development and progression, and are differentially expressed in normal tissues and cancers. However, the specific role of miRNAs in the metastatic process is still unknown. To seek a specific miRNA expression signature characterizing the metastatic phenotype of solid tumours, we performed a miRNA microarray analysis on 43 paired primary tumours (ten colon, ten bladder, 13 breast, and ten lung cancers) and one of their related metastatic lymph nodes. We identified a metastatic cancer miRNA signature comprising 15 overexpressed and 17 underexpressed miRNAs. Our results were confirmed by qRT-PCR analysis. Among the miRNAs identified, some have a well-characterized association with cancer progression, eg miR-10b, miR-21, miR-30a, miR-30e, miR-125b, miR-141, miR-200b, miR-200c, and miR-205. To further support our data, we performed an immunohistochemical analysis for three well-defined miRNA gene targets (PDCD4, DHFR, and HOXD10 genes) on a small series of paired colon, breast, and bladder cancers, and one of their metastatic lymph nodes. We found that the immunohistochemical expression of these targets significantly follows the corresponding miRNA deregulation. Our results suggest that specific miRNAs may be directly involved in cancer metastasis and that they may represent a novel diagnostic tool in the characterization of metastatic cancer gene targets.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-125"}
{"PMID":29588449,"Year":2018,"Title":"Confirmation of a metastasis-specific microRNA signature in primary colon cancer.","Abstract":"The identification of patients with high-risk stage II colon cancer who may benefit from adjuvant therapy may allow the clinical approach to be tailored for these patients based on an understanding of tumour biology. MicroRNAs have been proposed as markers of the prognosis or treatment response in colorectal cancer. Recently, a 2-microRNA signature (let-7i and miR-10b) was proposed to identify colorectal cancer patients at risk of developing distant metastasis. We assessed the prognostic value of this signature and additional candidate microRNAs in an independent, clinically well-defined, prospectively collected cohort of primary colon cancer patients including stage I-II colon cancer without and stage III colon cancer with adjuvant treatment. The 2-microRNA signature specifically predicted hepatic recurrence in the stage I-II group, but not the overall ability to develop distant metastasis. The addition of miR-30b to the 2-microRNA signature allowed the prediction of both distant metastasis and hepatic recurrence in patients with stage I-II colon cancer who did not receive adjuvant chemotherapy. Available gene expression data allowed us to associate miR-30b expression with axon guidance and let-7i expression with cell adhesion, migration, and motility.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":22692424,"Year":2012,"Title":"The lin-4 microRNA targets the LIN-14 transcription factor to inhibit netrin-mediated axon attraction.","Abstract":"miR-125 microRNAs, such as lin-4 in Caenorhabditis elegans, were among the first microRNAs discovered, are phylogenetically conserved, and have been implicated in regulating developmental timing. Here, we showed that loss-of-function mutations in lin-4 microRNA increased axon attraction mediated by the netrin homolog UNC-6. The absence of lin-4 microRNA suppressed the axon guidance defects of anterior ventral microtubule (AVM) neurons caused by loss-of-function mutations in slt-1, which encodes a repulsive guidance cue. Selective expression of lin-4 microRNA in AVM neurons of lin-4-null animals indicated that the effect of lin-4 on AVM axon guidance was cell-autonomous. Promoter reporter analysis suggested that lin-4 was likely expressed strongly in AVM neurons during the developmental time frame that the axons are guided to their targets. In contrast, the lin-4 reporter was barely detectable in anterior lateral microtubule (ALM) neurons, axon guidance of which is insensitive to netrin. In AVM neurons, the transcription factor LIN-14, a target of lin-4 microRNA, stimulated UNC-6-mediated ventral guidance of the AVM axon. LIN-14 promoted attraction of the AVM axon through the UNC-6 receptor UNC-40 [the worm homolog of vertebrate Deleted in Colorectal Cancer (DCC)] and its cofactor MADD-2, which signals through both the UNC-34 (Ena) and the CED-10 (Rac1) downstream pathways. LIN-14 stimulated UNC-6-mediated axon attraction in part by increasing UNC-40 abundance. Our study indicated that lin-4 microRNA reduced the activity of LIN-14 to terminate UNC-6-mediated axon guidance of AVM neurons.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-125"}
{"PMID":29940575,"Year":2018,"Title":"Knockdown of MiR-20a Enhances Sensitivity of Colorectal Cancer Cells to Cisplatin by Increasing ASK1 Expression.","Abstract":"BACKGROUND/AIMS: Platinum-based chemotherapy is one of the most important strategies for treatment of colorectal cancer. To improve the therapeutic efficiency, adjuvant drugs were sought to sensitize colorectal cancer cells to platinum-based agents such as cisplatin. As previous research has shown that miRNAs are associated with chemosensitivity, we aimed to alter miRNA regulation in colorectal cancer cells to increase their chemosensitivity. METHODS: MTT assays were performed to determine the viability of HT29, SW480, and LoVo cells. Quantitative real time polymerase chain reaction (qRT-PCR) was performed to examine the expression of miR-20a in these cell lines. Regulation of the miR-20a/ASK1 axis was confirmed by western blotting and luciferase reporter assays. After treatment with miR-20a inhibitor (anti-miR-20a) and cisplatin, production of reactive oxygen species (ROS), mitochondrial membrane potential, and apoptosis were measured by flow cytometry. Activation of ASK1, Bcl-xl, JNK, and caspase-9, -7, and -3 was detected by western blotting. RESULTS: miR-20a was overexpressed in colorectal cancer cell lines. Furthermore, knockdown of miR-20a increased the sensitivity of colorectal cancer cells to cisplatin treatment in vitro and in vivo. We demonstrated that the ASK1 gene was the target of miR-20a, and knockdown of miR-20a increased the expression of ASK1 in colorectal cancer cells. As cisplatin treatment induced production of ROS, knockdown of miR-20a enhanced ROS signaling through promoting the phosphorylation of ASK1. Phosphorylation of JNK and the subsequent mitochondrial apoptosis were triggered by the combination of cisplatin and anti-miR-20a. CONCLUSIONS: Knockdown of miR-20a enhanced sensitivity of colorectal cancer cells to cisplatin through the ROS/ASK1/JNK pathway.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-20"}
{"PMID":24096488,"Year":2014,"Title":"Impaired DICER1 function promotes stemness and metastasis in colon cancer.","Abstract":"Disruption of microRNA (miRNA) expression patterns is now being recognized as a hallmark of human cancer. The causes of these altered profiles are diverse, and, among them, we found the existence of defects in the miRNA processing machinery. However, little is known about how these alterations affect the biology of the underlying tumors. Herein, we show that colorectal cancer cells with an impairment in DICER1, a major miRNA biogenesis gene, undergo enrichment of tumor stemness features and an epithelial-to-mesenchymal transition. These phenotypes are associated with the downregulation of miRNAs, such as miR-34a, miR-126 and those of the miR-200 family, that target critical coding genes in these pathways. Most importantly, DICER1 impairment also induces the acquisition of a greater capacity for tumor initiation and metastasis, two properties associated with cancer stem cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-126"}
{"PMID":29589310,"Year":2018,"Title":"RT-qPCR for Fecal Mature MicroRNA Quantification and Validation.","Abstract":"By routinely and systematically being able to perform quantitative stem-loop reverse transcriptase (RT) followed by TaqMan(R) minor-groove binding (MGB) probe, real-time quantitative PCR analysis on exfoliated enriched colonocytes in stool, using human (Homo sapiens, hsa) micro(mi)RNAs to monitor changes of their expression at various stages of colorectal (CRC) progression, this method allows for the reliable and quantitative diagnostic screening of colon cancer (CC). Although the expression of some miRNA genes tested in tissue shows less variability in normal or cancerous patients than in stool, the noninvasive stool by itself is well suited for CC screening. An miRNA approach using stool promises to offer more sensitivity and specificity than currently used genomic, methylomic, or proteomic methods for CC screening.To present an application of employing miRNAs as diagnostic markers for CC screening, we carried out global microarray expression studies on stool colonocytes isolated by paramagnetic beads, using Affymetrix GeneChip miRNA 3.0 Array, to select a panel of miRNAs for subsequent focused semiquantitative PCR analysis studies. We then conducted a stem-loop RT-TaqMan(R) MGB probes, followed by a modified real-time qPCR expression study on 20 selected miRNAs for subsequent validation of the extracted immunocaptured total small RNA isolated from stool colonocytes. Results showed 12 miRNAs (miR-7, miR-17, miR-20a, miR-21, miR-92a, miR-96, miR-106a, miR-134, miR-183, miR-196a, miR-199a-3p, and miR214) to have an increased expression in stool of CC patients, and that later TNM stages exhibited more increased expressions than adenomas, while 8 miRNAs (miR-9, miR-29b, miR-127-5p, miR-138, miR-143, miR-146a, miR-222, and miR-938) showed decreased expressions in stool of CC patients, which becomes more pronounced as the cancer progresses from early to late TNM stages (0-IV).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-127"}
{"PMID":21354697,"Year":2011,"Title":"miR-203 reverses chemoresistance in p53-mutated colon cancer cells through downregulation of Akt2 expression.","Abstract":"In this study, we explored miR-203's role in the chemoresistance of colon cancer. We found that overexpression of miR-203 significantly decreased cell proliferation and survival, and induced cell apoptosis in the p53-mutated colon cancer cells. Importantly, miR-203 overexpression increased the cytotoxic role of paclitaxel in the p53-mutated colon cancer cells, but not in the p53 wild-type cells. We further demonstrated that the tumor suppressive role of miR-203 was mediated by negatively regulating Akt2 protein expression through mRNA degradation. The inhibition of Akt2 activity downregulated the protein expression of its downstream molecules involved in chemoresistance, such as MTDH and HSP90 genes. Also, overexpression of miR-203 decreased anti-apoptotic gene Bcl-xL expression and increased apoptotic proteins Bax and active caspase-3 levels. Our study is the first to identify the tumor suppressive role of overexpressed miR-203, describe its associated signaling pathways, and highlight the role of miR-203 in chemoresistance.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-20"}
{"PMID":25472670,"Year":2014,"Title":"Suitability of circulating miRNAs as potential prognostic markers in colorectal cancer.","Abstract":"miRNAs are crucial in cellular processes and have been shown to be abnormally expressed in cancer tissue and the circulation. Circulating miRNAs may serve as a novel class of minimally invasive biomarkers for prognosis. Within a first methodologic study, we evaluated the miRNA profile kinetics in the plasma of patients with colorectal cancer after surgical tumor removal to identify potential suitability as prognostic biomarkers. This pilot study is based on the ColoCare Study, a cohort study of newly diagnosed patients with stage I-IV colorectal cancer. Colorectal cancer pre- and postsurgical blood (2-7 days after surgery) and 6 months follow-up blood from 35 patients were examined and candidate miRNAs were investigated in the plasma. miRNA levels were measured by two-step qRT-PCR. Statistical analysis was performed using log-transformed normalized CT values using SAS 9.3. Comparing pre- and postsurgical miRNA levels revealed a statistically significant decrease of nine circulating miRNAs after surgery (miR92a, miR18a, miR320a, miR106a, miR16-2, miR20a, miR223, miR17, and miR143). Analyses of plasma levels over all three time points demonstrated a statistically significant decrease from presurgery to postsurgery and re-increase from postsurgery to the six months follow-up time point of four circulating miRNAs (miR92a, miR320a, miR106a, and miR18a). We were able to show for the first time that in plasma miRNA profiles change within days after colorectal cancer surgery. Our results underscore the role of the investigated miRNAs in colorectal cancer and their potential utility as prognostic biomarkers. See all the articles in this CEBP Focus section, \"Biomarkers, Biospecimens, and New Technologies in Molecular Epidemiology.\"","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-143"}
{"PMID":26954494,"Year":2016,"Title":"Support Vector Machine Based on microRNA Expression Profiles to Predict Histological Origin of Ampullary Carcinoma: Case Report of a Patient Affected From Adenocarcinoma of the Papilla of Vater With Lynch Syndrome.","Abstract":"Adenocarcinomas of Vater's papilla (PVAC) may originate from either the pancreatic duct or the intestinal epithelium. Conflicting data have been reported about the frequency of the 2 anatomical entities and their influence on patients' prognosis. To ascertain the anatomical origin of PVAC in a family member of a Lynch syndrome kindred, we searched for microRNA (miRNA) expression profiles on resected tumor specimens. The support vector machine was trained on our previous miRNAs expression data sets of pancreatic and colorectal tissue samples and used to classify the site of origin of the tumor in our patient. The support vector machine worked by contrasting the profiles of miRNAs in patients with pancreatic ductal and colorectal cancers to that of our patient, which was finally classified as pancreatic ductal adenocarcinoma accordingly to alterations of 55 miRNAs. The PVAC might be originated from ductal epithelium rather than from the intestinal mucosa of the papilla in the case at issue. Alteration of miR-548b-3p, miR-551a, miR-21, miR-92a, miR-let-7i, and miR-181a* emerged as potentially associated with cancer genetic susceptibility in PVAC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":27081702,"Year":2016,"Title":"Serum miR-125b is a non-invasive predictive biomarker of the pre-operative chemoradiotherapy responsiveness in patients with rectal adenocarcinoma.","Abstract":"BACKGROUND: Therapeutic management of Locally Advanced Rectal Cancer (LARC) involves pre-operative chemoradiotherapy (pCRT) followed by surgery. However, after pCRT the complete pathological response is approximately 20%, whereas in 20 to 40% of patients the response is poor or absent. METHODS: Cancer biopsy specimens (n= 38) and serum samples (n= 34) obtained before pCRT from 38 LARC patients were included in the study. Patients were classified in responders (R, tumor regression grade [TRG] 1-2; n= 16) and non-responders (NR, TRG 3-5; n= 22) according to the pathological response observed upon surgery. We performed miRNA microarrays analysis on biopsy specimens, and validated the selected candidates both by qRT-PCR (tissue and serum) and by in situ hybridization (tissue, miR-125b) analyses. RESULTS: Eleven miRNAs were significantly different between R and NR (miR-154, miR-409-3p, miR-127-3p, miR-214*, miR-299-5p and miR-125b overexpressed in NR; miR-33a, miR-30e, miR-338-3p, miR-200a and miR-378 decreased). In particular, miR-125b resulted to be the best candidate to discriminate the two groups (AUC of 0.9026; 95% CI, 0.7618-1.043). Additionally, miR-125b serum levels were significantly overexpressed in NR patients compared to R (p-value=0.0087), with an excellent discriminating power (AUC of 0.782; 95% CI, 0.6123-0.9518). CONCLUSIONS: The obtained results further support the clinical impact of miRNA analysis. High miR-125b expression in tissue and serum were associated with a poor treatment response in LARC patients, therefore miR-125b could be considered as a possible novel non-invasive biomarker of response in LARC treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-299"}
{"PMID":26547791,"Year":2015,"Title":"Functional variants inPXRare associated with colorectal cancer susceptibility in Chinese populations.","Abstract":"BACKGROUND: As an important member of the steroid nuclear receptor family, recent research has suggested that PXR may play important roles in the development of multiple cancers. However, no well-designed studies has been conducted to investigate the associations between genetic polymorphisms of PXR and colorectal cancer (CRC) risk in Chinese populations. MATERIALS AND METHODS: We performed a hospital-based case-control analysis to assess two genetic polymorphisms in the 3'-untranslated regions (3'-UTR) via allele-specific MALDI-TOF mass spectrometry assay and evaluated the associations between two polymorphisms and risk of CRC. RESULTS: The PXR rs3814058C>T polymorphism was significantly associated with a higher risk of CRC (P<10-3), and the CT/TT variant genotypes had an increased CRC risk (adjusted odds ratio=1.54, 95% confidence interval=1.27-1.83) comparing CC genotype. In stratified analyses, rs3814058CT+TT genotypes was associated with increased risk among alcohol consumers (P=0.002). In vitro experiments indicated that the rs3814058C to rs3814058T transition gained a new binding of the microRNA hsa-miR-129-5p and decreased the PXR expression. CONCLUSIONS: Our data suggest that the functional polymorphism rs3814058C>T in 3'-UTR of PXR may be a functional biomarker to predict risk of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-129"}
{"PMID":29048669,"Year":2017,"Title":"MicroRNA337 inhibits colorectal cancer progression by directly targeting KRAS and suppressing the AKT and ERK pathways.","Abstract":"Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death worldwide. Tumour progression and development in CRC is a multi-step process involving a large number of genetic and epigenetic alterations. Previous studies indicated that abnormally expressed microRNAs play critical roles in CRC through regulation of oncogenic and tumour-suppressor genes. Hence, determination of the function of microRNAs may provide novel therapeutic targets for CRC diagnosis and treatments. MicroRNA337 (miR337) has been reported to be downregulated in several cancer types. However, the expression, function and underlying mechanisms of miR337 in CRC have not been clearly elucidated. In this study, miR337 was significantly decreased in CRC tissues and cell lines. Low miR337 expression level was correlated with lymph node metastasis, distant metastasis and TNM stage of CRC patients. In addition, upregulation of miR337 suppressed cell proliferation and invasion and promoted apoptosis in CRC. Based on bioinformatics analysis, we assumed that Kirsten rat sarcoma viral oncogene homolog (KRAS) was directly modulated by miR337 in CRC. Luciferase reporter assay demonstrated the direct interaction between miR337 and 3'UTR of KRAS mRNA. Furthermore, reverse transcription-quantitative polymerase chain reaction and western blot analysis indicated that miR337 could negatively regulate endogenous KRAS expression in CRC cells at both mRNA and protein levels. Moreover, KRAS was highly expressed in CRC tissues and inversely correlated with miR337 expression in CRC tissues. KRAS knockdown recapitulates effects similar to those induced by miR337 overexpression in CRC cells, whereas KRAS overexpression partially restored the tumour suppressive effects of miR337. Besides, ectopic expression of miR337 inactivates the AKT and ERK signalling pathways in CRC. These results suggested that miR337 may act as a tumour suppressor during the process of CRC malignant transformation by interacting with KRAS.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-337"}
{"PMID":30473751,"Year":2018,"Title":"MiR-192, miR-200c and miR-17 are fibroblast-mediated inhibitors of colorectal cancer invasion.","Abstract":"Colorectal cancer remains a leading cause of cancer-related death worldwide. A previous transcriptomics based study characterized molecular subgroups of which the stromal subgroup was associated with the worst clinical outcome. Micro-RNAs (miRNAs) are well-known regulators of gene expression and can follow a non-linear repression mechanism. We set up a model combining piecewise linear and linear regression and applied this combined regression model to a comprehensive colon adenocarcinoma dataset. We identified miRNAs involved in regulating characteristic gene sets, particularly extracellular matrix remodeling in the stromal subgroup. Comparison of expression data from separated (epithelial) cancer cells and stroma cells or fibroblasts associate these regulatory interactions with infiltrating stromal or tumor-associated fibroblasts. MiR-200c, miR-17 and miR-192 were identified as the most promising candidates regulating genes crucial for extracellular matrix remodeling. We validated our computational findings by in vitro assays. Enforced expression of either miR-200c, miR-17 or miR-192 in untransformed human colon fibroblasts down-regulated 85% of all predicted target genes. Expressing these miRNAs singly or in combination in human colon fibroblasts co-cultured with colon cancer cells considerably reduced cancer cell invasion validating these miRNAs as cancer cell infiltration suppressors in tumor associated fibroblasts.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-192"}
{"PMID":18695884,"Year":2008,"Title":"Micro-RNAs miR125b and miR137 are frequently upregulated in response to capecitabine chemoradiotherapy of rectal cancer.","Abstract":"There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":26329295,"Year":2016,"Title":"MicroRNA-33b inhibits tumor cell growth and is associated with prognosis in colorectal cancer patients.","Abstract":"PURPOSE: To explore the role of miR-33b in colorectal cancer (CRC) and the correlation between its expression and prognosis. METHODS: The expressions of miR-33b between CRC tissues and normal tissues were measured by real-time PCR. The effects of miR-33b on cell proliferation and cell cycle progression were detected by MTT assay, colony formation assay and flow cytometry. The potential regulations of miR-33b on multiple genes expression were verified by Western blot. Furthermore, the association of miR-33b with CRC clinicopathologic features and prognosis was analyzed by Chi-squared test and Kaplan-Meier tests. RESULTS: MiR-33b was downregulated in CRC compared with normal colorectal samples and miR-33b inhibited tumor cell growth and induced cell cycle arrest. Western blot assays and correlation analysis showed that miR-33b could regulate multiple growth-related genes. Moreover, the expression of miR-33b was associated with TNM stage and tumor size, and CRC patients with high miR-33b expression had a better prognosis. CONCLUSION: Our data suggest that miR-33b functions as a tumor suppressor gene in CRC through regulating cell proliferation and cell cycle.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-33"}
{"PMID":25990502,"Year":2015,"Title":"Preoperative Prediction of Lymph Node Status by Circulating Mir-18b and Mir-20a During Chemoradiotherapy in Patients with Rectal Cancer.","Abstract":"BACKGROUND: In locally advanced rectal cancer, therapeutic success of preoperative chemoradiotherapy (CRT) ranges from resistance to complete regression. For those patients that respond well to CRT, local resection (LR) procedures are currently under investigation to minimize surgical morbidity and to improve functional outcome. To maintain the oncologic benefit appropriate staging procedures are essential. However, current clinical assessment and imaging techniques need further improvement. METHODS: Five miRNAs associated with rectal cancer (miR-17, miR-18b, miR-20a, miR-31, and miR-193-3p) were analyzed in the plasma of rectal cancer patients (n = 42) using qPCR. Expression levels were assessed before, during and after CRT and analyzed in regard to patients' lymph node status obtained after total mesorectal excision and intensive histopathological work-up. RESULTS: Four of the five miRNAs revealed reliable results in the plasma. miR-31 was excluded due to its low expression. MicroRNA-17, 18b, 20a, and 193-3p showed altering expression levels at different time points. Only 43% (miR-17), 43% (miR-18b), 53% (miR-20a), and 60% (miR-193-3p) showed a continuous in- or decrease of miRNA expression. The reduced expression of miR-18b and miR-20a during CRT was found to be significantly associated with postoperative lymph node negativity (p < 0.05). CONCLUSION: MicroRNA expression in patient plasma changes during preoperative CRT. The alteration is not continuous and the meaning requires additional analysis on a larger patient cohort. The co-occurrence of reduced miR-18b and miR-20a expression with lymph node negativity after preoperative CRT could help to stratify the surgical procedure with respect to total mesorectal excision and LR if validated prospectively.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-31"}
{"PMID":21174058,"Year":2011,"Title":"MicroRNA expression profiles in human colorectal cancers with liver metastases.","Abstract":"At present, a full understanding of the mechanisms by which colorectal cancer (CRC) distant metastases form is still beyond our reach because of the intricate regulation of gene expression. MicroRNAs (miRNAs) are shown to be involved in various human diseases including cancers through negative regulation of target gene expression at the post-transcriptional level. However, there are only a few studies on the roles of miRNA aberrations in liver metastasis of human colorectal cancer. To identify miRNA expression patterns associated with liver metastasis in human colorectal cancer, the miRNA expression profiles of colorectal cancer tissues with liver metastasis and their non-metastatic counterparts were studied using microRNA microarrays and further confirmed by quantitative RT-PCR. We show that 28 miRNAs are differentially expressed in the colorectal carcinomas with liver metastasis compared to the non-metastatic counterparts. Of these, 4 miRNAs including miR-150*, miR-125b-2*, miR-1179 and miR-139-3p were up-regulated in colorectal cancers with liver metastasis while the others were down-regulated. The target genes of selected deregulated miRNAs were predicted through bioinformatic techniques with two functional analyses, gene ontology and KEGG analysis, which showed that categories of high enrichment GOs and specific pathways targeted by dysregulated miRNAs were involved in liver metastasis during human colorectum carcinogenesis. Our results indicated that miRNAs are not only involved in carcinogenesis of colorectum, but may also participate in the progression such as with liver metastases in human colorectal cancers.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-139"}
{"PMID":22898888,"Year":2012,"Title":"Irinotecan induces senescence and apoptosis in colonic cells in vitro.","Abstract":"Irinotecan (CPT-11) is topoisomerase I inhibitor used in the treatment of disseminated colorectal cancer. In colon cancer cells it induces DNA damage which leads to cytotoxicity with ensuing apoptosis or premature senescence. Despite its clinical use and efficiency in malignant colonocytes, its effects in normal colonic cells are relatively underexplored. In this work we report that CPT-11 induces dose-dependent cytotoxicity which results in apoptosis and premature senescence whose occurrence nevertheless varies in relation to the type of exposed cells. In normal colonic epithelial cells (NCM) the prevailing type of response is apoptosis whereas in normal colonic fibroblasts (NCF) it is premature senescence. Further analyses showed that CPT-11 induced in both types of cells DNA damage and activated stress response pathways including p53 and p16 but with varying activity of stress kinase p38 and selected stress-associated microRNAs. Epithelial cells upregulated the expression of p53, which was subsequently specifically phosphorylated, massively activated p38 and initiated mitochondrial, caspase-dependent apoptosis. These events occurred in the presence of moderately increased expression of miR-34a only. Conversely, in colonic fibroblasts p38 was only moderately activated, p53 as well as p16 expressions were upregulated in the presence of increased expression of miR-34a, miR-128a and miR-449a. Caspase-dependent apoptosis was found only in a minority of treated cells and the premature senescence phenotype was prevailing. Specific inhibition further proved that p53-dependent as well as independent mechanisms might be responsible for these cell type-specific differences.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":27601590,"Year":2017,"Title":"Genome-Wide miRNA Analysis Identifies miR-188-3p as a Novel Prognostic Marker and Molecular Factor Involved in Colorectal Carcinogenesis.","Abstract":"Purpose: Characterization of colorectal cancer transcriptome by high-throughput techniques has enabled the discovery of several differentially expressed genes involving previously unreported miRNA abnormalities. Here, we followed a systematic approach on a global scale to identify miRNAs as clinical outcome predictors and further validated them in the clinical and experimental setting.Experimental Design: Genome-wide miRNA sequencing data of 228 colorectal cancer patients from The Cancer Genome Atlas dataset were analyzed as a screening cohort to identify miRNAs significantly associated with survival according to stringent prespecified criteria. A panel of six miRNAs was further validated for their prognostic utility in a large independent validation cohort (n = 332). In situ hybridization and functional experiments in a panel of colorectal cancer cell lines and xenografts further clarified the role of clinical relevant miRNAs.Results: Six miRNAs (miR-92b-3p, miR-188-3p, miR-221-5p, miR-331-3p, miR-425-3p, and miR-497-5p) were identified as strong predictors of survival in the screening cohort. High miR-188-3p expression proves to be an independent prognostic factor [screening cohort: HR = 4.137; 95% confidence interval (CI), 1.568-10.917; P = 0.004; validation cohort: HR = 1.538; 95% CI, 1.107-2.137; P = 0.010, respectively]. Forced miR-188-3p expression increased migratory behavior of colorectal cancer cells in vitro and metastases formation in vivo (P < 0.05). The promigratory role of miR-188-3p is mediated by direct interaction with MLLT4, a novel identified player involved in colorectal cancer cell migration.Conclusions: miR-188-3p is a novel independent prognostic factor in colorectal cancer patients, which can be partly explained by its effect on MLLT4 expression and migration of cancer cells. Clin Cancer Res; 23(5); 1323-33. (c)2016 AACR.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-425"}
{"PMID":25782327,"Year":2015,"Title":"DPD and UGT1A1 deficiency in colorectal cancer patients receiving triplet chemotherapy with fluoropyrimidines, oxaliplatin and irinotecan.","Abstract":"AIMS: Triplet chemotherapy with fluoropyrimidines, oxaliplatin and irinotecan is a standard therapy for metastatic colorectal cancer (CRC). Single nucleotide polymorphisms (SNPs) in DPYD and UGT1A1 influence fluoropyrimdines and irinotecan adverse events (AEs). Low frequency DPYD variants (c.1905 + 1G > A, c.1679 T > G, c.2846A > T) are validated but more frequent ones (c.496A > G, c.1129-5923C > G and c.1896 T > C) are not. rs895819 T > C polymorphism in hsa-mir-27a is associated with reduced DPD activity. In this study, we evaluated the clinical usefulness of a pharmacogenetic panel for patients receiving triplet combinations. METHODS: Germline DNA was available from 64 CRC patients enrolled between 2008 and 2013 in two phase II trials of capecitabine, oxaliplatin and irinotecan plus bevacizumab or cetuximab. SNPs were determined by Real-Time PCR. We evaluated the functional variants in DPYD (rare: c.1905 + 1G > A, c.1679 T > G, c.2846A > T; most common: c.496A > G, c.1129-5923C > G, c.1896 T > C), hsa-mir-27a (rs895819) and UGT1A1 (*28) genes to assess their association with grade 3-4 AEs. RESULTS: None of the patients carried rare DPYD variants. We found DPYD c.496A > G, c.1129-5923C > G, c.1896 T > C in heterozygosity in 19%, 5% and 8%, respectively, homozygous rs895819 in hsa-mir-27a in 9% and homozygous UGT1A1*28 in 8%. Grade 3-4 AEs were observed in 36% patients and were associated with DPYD c.496A > G (odds ratio (OR) 4.93, 95% CI 1.29, 18.87; P = 0.021) and homozygous rs895819 in hsa-mir-27a (OR 11.11, 95% CI 1.21, 102.09; P = 0.020). Carriers of DPYD c.1896 T > C and homozygous UGT1A1*28 showed an OR of 8.42 (95% CI 0.88, 80.56; P = 0.052). Multivariate analysis confirmed an independent value for DPYD c.496A > G and c.1896 T > C. CONCLUSIONS: Concomitant assessment of DPYD variants and the UGT1A1*28 allele is a promising strategy needing further validation for dose personalization.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-27"}
{"PMID":21625210,"Year":2011,"Title":"LIN28B fosters colon cancer migration, invasion and transformation through let-7-dependent and -independent mechanisms.","Abstract":"Lin28b is an RNA-binding protein that inhibits biogenesis of let-7 microRNAs. LIN28B is overexpressed in diverse cancers, yet a specific role in the molecular pathogenesis of colon cancer has to be elucidated. We have determined that human colon tumors exhibit decreased levels of mature let-7 isoforms and increased expression of LIN28B. To determine LIN28B's mechanistic role in colon cancer, we expressed LIN28B in immortalized colonic epithelial cells and human colon cancer cell lines. We found that LIN28B promotes cell migration, invasion and transforms immortalized colonic epithelial cells. In addition, constitutive LIN28B expression increases expression of intestinal stem cell markers LGR5 and PROM1 in the presence of let-7 restoration. This may occur as a result of Lin28b protein binding LGR5 and PROM1 mRNA, suggesting that a subset of LIN28B functions is independent of its ability to repress let-7. Our findings establish a new role for LIN28B in human colon cancer pathogenesis, and suggest LIN28B post-transcriptionally regulates LGR5 and PROM1 through a let-7-independent mechanism.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7-"}
{"PMID":29720118,"Year":2018,"Title":"microRNA-451a regulates colorectal cancer proliferation in response to radiation.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is a leading cause of cancer-related death. The biologic response of CRC to standard of care adjuvant therapies such as chemotherapy and radiation are poorly understood. MicroRNAs (miRs) have been shown to affect CRC progression and metastasis. Therefore, we hypothesized that specific miRs modulate CRC response to chemoradiation. METHODS: In this study, we used miR expression profiling and discovered a set of microRNAs upregulated rapidly in response to either a single 2 Gy dose fraction or a 10 Gy dose of gamma-radiation in mouse colorectal carcinoma models. We used gain and loss-of-function studies in 2D and 3Dcell proliferation assays and colony formation assays to understand the role of the top miR candidate from our profiling. We used Student's T-tests for simple comparisons and two-factor ANOVA for evaluating significance. RESULTS: The most upregulated candidate at early time points in our signature, miR-451a inhibited tumor cell proliferation and attenuated surviving fraction in longer-term cultures. Conversely, inhibition of miR-451a increased proliferation, tumorsphere formation, and surviving fraction of tumor cells. Using a bioinformatics approach, we identified four genes, CAB39, EMSY, MEX3C, and EREG, as targets of miR-451a. Transfection of miR-451a decreased both mRNA and protein levels of these targets. Importantly, we found miR-451a expression was high and CAB39, EMSY levels were low in a small subset of rectal cancer patients who had a partial response to chemoradiation when compared to patients that had no response. Finally, analysis of a TCGA colorectal cancer dataset revealed that CAB39 and EMSY are upregulated at the protein level in a significant number of CRC patients. Higher levels of CAB39 and EMSY correlated with poorer overall survival. CONCLUSIONS: Taken together, our data indicates miR-451a is induced by radiation and may influence colorectal carcinoma proliferation via CAB39 and EMSY pathways.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-451"}
{"PMID":29737579,"Year":2018,"Title":"Beta-elemene increases chemosensitivity to 5-fluorouracil through down-regulating microRNA-191 expression in colorectal carcinoma cells.","Abstract":"Colorectal carcinoma is a common malignant tumor occurring in the alimentary system. Despite developments of modern medicine, developed resistance to 5-fluorouracil (5-FU) may lead to poor prognosis. Herein, we aimed to explore the effects of beta-elemene on colorectal carcinoma cells (HCT116 and HT29) as well as the underlying mechanisms. Beta-elemene reduced cell viability and induced apoptosis in HCT116 and HT29 cells. Increased apoptosis following beta-elemene exposure was due to enhanced sensitivity to 5-FU through down-regulating miR-191. Expression of key kinases, including Wnt3a, and beta-catenin, were down-regulated by beta-elemene through a miR-191 mechanism. Moreover, beta-elemene might improve resistance of colorectal carcinoma cells to 5-FU by down-regulating miR-191, thereby inhibiting the Wnt/beta-catenin pathway.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-191"}
{"PMID":25197016,"Year":2014,"Title":"MiR-107 and miR-99a-3p predict chemotherapy response in patients with advanced colorectal cancer.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are involved in numerous biological and pathological processes including colorectal cancer (CRC). The aim of our study was to evaluate the ability of miRNA expression patterns to predict chemotherapy response in a cohort of 78 patients with metastatic CRC (mCRC). METHODS: We examined expression levels of 667 miRNAs in the training cohort and evaluated their potential association with relevant clinical endpoints. We identified a miRNA profile that was analysed by RT-qPCR in an independent cohort. For a set of selected miRNAs, bioinformatic target predictions and pathway analysis were also performed. RESULTS: Eight miRNAs (let-7 g*, miR-107, miR-299-5p, miR-337-5p, miR-370, miR-505*, miR-889 and miR-99a-3p) were significant predictors of response to chemotherapy in the training cohort. In addition, overexpression of miR-107, miR-337-5p and miR-99a-3p, and underexpression of miR-889, were also significantly associated with improved progression-free and/or overall survival. MicroRNA-107 and miR-99a-3p were further validated in an independent cohort as predictive markers for chemotherapy response. In addition, an inverse correlation was confirmed in our study population between miR-107 levels and mRNA expression of several potential target genes (CCND1, DICER1, DROSHA and NFKB1). CONCLUSIONS: MiR-107 and miR-99a-3p were validated as predictors of response to standard fluoropyrimidine-based chemotherapy in patients with mCRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-299"}
{"PMID":28114282,"Year":2017,"Title":"The miR-487b-3p/GRM3/TGFbeta signaling axis is an important regulator of colon cancer tumorigenesis.","Abstract":"Molecular targeting is an import strategy to treat advanced colon cancer. The current study demonstrates that expression of GRM3, a metabotropic glutamate receptor mainly expressed in mammalian central nervous system, is significantly upregulated in majority of human colonic adenocarcinomas tested and colon cancer cell lines. Knockdown of GRM3 expression or inhibition of GRM3 activation in colon cancer cells reduces cell survival and anchorage-independent growth in vitro and inhibits tumor growth in vivo. Mechanistically, GRM3 antagonizes TGFbeta-mediated activation of protein kinase A and inhibition of Protein kinase B (AKT). In addition, TGFbeta signaling increases GRM3 protein stability and knockdown of GRM3 enhances TGFbeta-mediated tumor suppressor function. Further studies indicate that miR-487b-3p directly targets GRM3. Overexpression of miR-487b-3p mimics the effects of GRM3 knockdown and suppresses the tumorigenicity of colon cancer cells in vivo. Expression of miR-487b-3p is decreased in colon adenocarcinomas and inversely correlates with GRM3 expression. Taken together, these studies indicate that upregulation of GRM3 expression is a functionally important molecular event in colon cancer, and that GRM3 is a promising molecular target for colon cancer treatment. This is particularly interesting and important from a therapeutic standpoint because numerous metabotropic glutamate receptor antagonists are available, many of which have been found unsuitable for treatment of neuropsychiatric disorders for reasons such as inability to readily penetrate blood brain barriers. As GRM3 is upregulated in colon cancer, but rarely expressed in normal peripheral tissues, targeting GRM3 with such agents would not likely cause adverse neurological or peripheral side effects, making GRM3 an attractive and specific molecular target for colon cancer treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-487"}
{"PMID":29374690,"Year":2018,"Title":"MicroRNA Expression in KRAS- and BRAF-mutated Colorectal Cancers.","Abstract":"BACKGROUND/AIM: KRAS and BRAF are two genes commonly mutated in colorectal cancer (CRC). Even though BRAF is a downstream target of KRAS in the MAPK signalling pathway, KRAS- and BRAF-mutated CRCs are found to display several different clinical and histopathological features. We investigated whether a differential expression of microRNAs (miRNAs) could explain the clinicopathological differences seen between KRAS- and BRAF-mutated CRCs. MATERIALS AND METHODS: Using a PCR array, we analyzed the expression of 84 different miRNAs in CRC cell lines wild-type in KRAS and BRAF, or mutated in KRAS or BRAF. RESULTS: Ten miRNAs were selected for further analyses in tumor tissue specimens (let-7a, let-7i, miR-10a, miR-10b, miR-31, miR-100, miR-181a, miR-181b, miR-372, and miR-373). BRAF-mutated tumors were found to express significantly higher levels of miR-31 as well as significantly lower levels of miR-373, compared to wild-type tumors. CONCLUSION: Our results suggest that KRAS- and BRAF-mutated CRCs may have different miRNA signatures compared to CRC tumors wild-type in KRAS and BRAF. However, no difference in expression levels between KRAS- and BRAF-mutated tumors was evident for the miRNAs analyzed in this study.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-100"}
{"PMID":26681654,"Year":2016,"Title":"Intra-tumor heterogeneity of microRNA-92a, microRNA-375 and microRNA-424 in colorectal cancer.","Abstract":"UNLABELLED: Various microRNAs (miRNAs) have been investigated in order to improve diagnostics and risk assessment in colorectal cancer (CRC). To clarify the potential of miRNA profiling in CRC, knowledge of intra-tumor heterogeneity in expression levels is crucial. The study aim was to estimate the intra-tumor variance of three selected miRNAs: miR-92a, miR-375 and miR-424 in CRC tissue. MATERIAL AND METHODS: A retrospective study on archived formalin-fixed paraffin embedded tissue from 9 patients with CRC. miRNA tissue expression levels were analyzed by qRT-PCR on tissue representing luminal, central and invasive border zones. Variance components were estimated based on Cp values using mixed modeling and presented as coefficients of variation (CV). RESULTS: Intra-tumor variance was approximately half of the variance observed between patients with a mean intra-tumor CV of 56.4% (range 33.1-77.1%) and a mean inter-patient CV of 101.7% (range 48.8-152.7%). Furthermore we found a significant systematic difference in expression levels between tumor zones for miR-92a and miR-375 with a luminal-invasive difference equal to 0.60 Cp (95% CI: 0.30-0.89, p=0.0003) for miR-92a and a luminal-invasive difference equal to 0.78 Cp (95% CI: 0.10-1.46, p=0.027) for miR-375. Conclusion While the intra-tumor variance of miR-92a, miR-375 and miR-424 is substantial, it only constitutes approximately 30% of the total variation. Functional deregulation between tumor zones might contribute to variations in measured expression levels, and thus knowledge of specific intra-tumor expression patterns is crucial in tissue sampling for research as well as in future diagnostics.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-424"}
{"PMID":31241203,"Year":2019,"Title":"Evaluation of fecal microRNA stability in healthy cats.","Abstract":"BACKGROUND: Gastrointestinal (GI) cancer accounts for 14% of feline malignancies. There is a great need for reliable noninvasive diagnostic biomarkers to reach a timely diagnosis and initiate treatment. Fecal microRNAs (miRNAs) could be such a biomarker and have shown great potential in colorectal screening in people but have yet to be investigated in cats. OBJECTIVES: We aimed to evaluate the presence and stability of feline fecal miRNA under different storage conditions (room temperature [RT], 4, and -20 degrees C) and to evaluate the expression levels of specific fecal miRNAs collected on three separate days (days 1, 4, and 7) in healthy cats. METHODS: Healthy cats were prospectively recruited. Fecal samples were collected, aliquoted, and stored for 24 hours at RT and then transferred to -20 degrees C, stored for 24 hours at 4 degrees C and then transferred to -20 degrees C, or were immediately placed at -20 degrees C on day 1 or at -20 degrees C on days 4 and 7 postcollection. Expression of 22 miRNAs was investigated using quantitative real-time PCR. RESULTS: Ten miRNA assays worked well, and one, let-7b, was used for normalization. No differences in miRNA expression were seen between the three storage temperatures for the nine miRNAs investigated. Only miR-26a showed a significant increase in expression between samples of days 1 and 7. The rest of the miRNAs levels were stable over time. CONCLUSIONS: Fecal miRNA can be isolated from healthy cats. The expression was stable at different temperatures and for most of the miRNAs over time. Prospective studies evaluating fecal miRNA as biomarkers in cats with GI neoplasia are warranted.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":28651018,"Year":2017,"Title":"Meta-analysis of miRNA expression profiles for prostate cancer recurrence following radical prostatectomy.","Abstract":"BACKGROUND: Prostate cancer (PCa) is a leading reason of death in men and the most diagnosed malignancies in the western countries at the present time. After radical prostatectomy (RP), nearly 30% of men develop clinical recurrence with high serum prostate-specific antigen levels. An important challenge in PCa research is to identify effective predictors of tumor recurrence. The molecular alterations in microRNAs are associated with PCa initiation and progression. Several miRNA microarray studies have been conducted in recurrence PCa, but the results vary among different studies. METHODS: We conducted a meta-analysis of 6 available miRNA expression datasets to identify a panel of co-deregulated miRNA genes and overlapping biological processes. The meta-analysis was performed using the 'MetaDE' package, based on combined P-value approaches (adaptive weight and Fisher's methods), in R version 3.3.1. RESULTS: Meta-analysis of six miRNA datasets revealed miR-125A, miR-199A-3P, miR-28-5P, miR-301B, miR-324-5P, miR-361-5P, miR-363*, miR-449A, miR-484, miR-498, miR-579, miR-637, miR-720, miR-874 and miR-98 are commonly upregulated miRNA genes, while miR-1, miR-133A, miR-133B, miR-137, miR-221, miR-340, miR-370, miR-449B, miR-489, miR-492, miR-496, miR-541, miR-572, miR-583, miR-606, miR-624, miR-636, miR-639, miR-661, miR-760, miR-890, and miR-939 are commonly downregulated miRNA genes in recurrent PCa samples in comparison to non-recurrent PCa samples. The network-based analysis showed that some of these miRNAs have an established prognostic significance in other cancers and can be actively involved in tumor growth. Gene ontology enrichment revealed many target genes of co-deregulated miRNAs are involved in \"regulation of epithelial cell proliferation\" and \"tissue morphogenesis\". Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that these miRNAs regulate cancer pathways. The PPI hub proteins analysis identified CTNNB1 as the most highly ranked hub protein. Besides, common pathway analysis showed that TCF3, MAX, MYC, CYP26A1, and SREBF1 significantly interact with those DE miRNA genes. The identified genes have been known as tumor suppressors and biomarkers which are closely related to several cancer types, such as colorectal cancer, breast cancer, PCa, gastric, and hepatocellular carcinomas. Additionally, it was shown that the combination of DE miRNAs can assist in the more specific detection of the PCa and prediction of biochemical recurrence (BCR). CONCLUSION: We found that the identified miRNAs through meta-analysis are candidate predictive markers for recurrent PCa after radical prostatectomy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-28"}
{"PMID":27658891,"Year":2016,"Title":"MicroRNA Signatures of Colonic Polyps on Screening and Histology.","Abstract":"Colorectal cancer and adenoma adjacent to cancer exhibit distinct microRNA (miRNA) alterations in an apparent mucosa-to-adenocarcinoma sequence. The pattern of microRNAs in screen-detected polyps in relation to histologic features and cancer risk has not been investigated. miRNA expression analysis was performed on normal mucosa (NM), hyperplastic polyps (HP), tubular adenomas (TA), tubulovillous adenomas or high-grade dysplasia (TVHG), and serrated polyps [sessile serrated adenoma/polyps (SSA/P) and traditional serrated adenomas (TSA)] in biopsy specimens from 109 patients undergoing screening/surveillance colonoscopy. Generalized linear models were used to identify differentially expressed miRNAs by histologic type and logistic regression to identify miRNA predictors of histopathology. False discovery rate (FDR) was used to control for multiple comparisons. We identified 99 miRNAs differing in at least one of five histopathologic groups (FDR <\/=0.05). In a comparison of HPNM versus TVHG, the top most upregulated and downregulated miRNAs in HPNM included miR-145, -143, -107, -194, and -26a (upregulated), and miR-663, -1268, -320b, -1275, and -320b (downregulated; FDR P < 0.05). miR-145 and -619 showed high accuracy to discriminate low- from high-risk polyps without serrated histology (TVHG vs. HPNM + TA; CI, 95.6%), whereas miR-124, -143, and -30a showed high accuracy of separating high-risk polyps (TVHG + TSA) from low-risk polyps (HPNM + TA + SSA/P; CI, 96.0%). For TSAs, miR-125b and -199a were uniquely downregulated relative to HPNMs, and miR-335, -222, and -214 discriminated between non-serrated and serrated histology. Our data support the presence of colorectal cancer-associated miRNA alterations in screen-detected adenomas that may be useful for risk stratification for surveillance interval planning. Cancer Prev Res; 9(12); 942-9. (c)2016 AACR.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-143"}
{"PMID":27698796,"Year":2016,"Title":"Mechanism analysis of colorectal cancer according to the microRNA expression profile.","Abstract":"The present study aimed to identify specific microRNAs (miRs) and their predicted target genes to clarify the molecular mechanisms of colorectal cancer (CRC). An miR expression profile (array ID, GSE39833), which consisted of 88 CRC samples with various tumor-necrosis-metastasis stages and 11 healthy controls, was downloaded from the Gene Expression Omnibus database. Subsequently, the differentially expressed miRs and their target genes were screened. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways of target genes were analyzed using the Database for Annotation Visualization and Integrated Discovery. A protein-protein interaction (PPI) network of the target genes was constructed using the Search Tool for the Retrieval of Interacting Genes database. The present study identified a total of 18 differentially expressed miRs (upregulated, 8; downregulated, 10) in the sera of the CRC patients compared with the healthy controls. Of these, 3 upregulated (let-7b, miR-1290 and miR-126) and 2 downregulated (miR-16 and miR-760) differentially expressed miRs and their target genes, including cyclin D1 (CCND1), v-myc avian myelocytomatosis viral oncogene homolog (MYC), phosphoinositide-3-kinase, regulatory subunit 2 (beta) (PIK3R2) and SMAD family member 3 (SMAD3), were significantly enriched in the CRC developmental pathway. All these target genes had higher node degrees in the PPI network. In conclusion, let-7b, miR-1290, miR-126, miR-16 and miR-760 and their target genes, CCND1, MYC, PIK3R2 and SMAD3, may be important in the molecular mechanisms for the progression of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-760"}
{"PMID":26747706,"Year":2016,"Title":"miR-137 Regulates the Tumorigenicity of Colon Cancer Stem Cells through the Inhibition of DCLK1.","Abstract":"UNLABELLED: miRNAs have important roles in regulating cancer stem cell (CSC) properties and are considered to be potential therapeutic targets. However, few studies have focused on miRNAs which are specifically related to colon CSCs. Here, a PCR-based miRNA profiling analysis of normal colon stem cells (NCSC) and colon CSCs (EpCAM(+)/CD44(+)/CD66a(-)) identified miRNAs which regulate colon CSC properties. Interestingly, miRNA-137 (miR-137) expression was downregulated in the colon CSCs compared with NCSCs, while doublecortin-like kinase 1(DCLK1) mRNA was highly expressed in the colon CSCs but low in the NCSCs. In fact, DCLK1-positive cancer cells were widely distributed in clinically resected colon cancer specimens, while DCLK1-positve epithelial cells were rarely detected in normal colon tissues including the crypt bottoms. Luciferase assay and immunoblot analysis revealed that miR-137 regulated DCLK1 gene expression. Transduction of exogenous miR-137 suppressed the development of colon cancer organoids in vitro and the tumorigenicity of colon cancer cells in vivo without affecting the growth of normal intestinal organoids. Furthermore, the suppression of miR-137 enhanced the organoid development of normal colon cells. These data demonstrate that miR-137 has the capacity to suppress the tumorigenicity of colon CSCs and that maintained expression of miR-137 in NCSCs contributes to suppressing uncontrolled cell proliferation through the inhibition of DCLK1 expression. IMPLICATIONS: The miR-137/DCLK1 axis as an important regulator in NCSCs and colon CSCs; further understanding of this axis may foster the development of potential gene therapeutic strategies targeting colon CSCs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-137"}
{"PMID":29115526,"Year":2018,"Title":"The long non-coding RNA ENST00000547547 reduces 5-fluorouracil resistance of colorectal cancer cells via competitive binding to microRNA-31.","Abstract":"Colorectal cancer (CRC) is one of the most common cancers and the third leading cause of cancer-related deaths due to its rapid progression and poor prognosis. 5-Fluorouracil (5-FU)-based chemotherapies are the standard treatment for locally advanced CRC. However, a considerable percentage of CRCs have inherent or acquired 5-FU resistance, which critically impedes clinical outcomes. In the present study, we reported that the expression level ENST00000547547 was downregulated in 5-FU-resistant CRC cells in comparison with the parental cells, While rising with the treatment of 5-FU in parental cells. Overexpression of ENST00000547547 promoted 5-FU-induced cell apoptosis and reduced the chemoresistance of 5-FU in vitro. Moreover, we found that ENST00000547547 was a target of miR-31, as confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay. Notably, miR-31 was upregulated in 5-FU-resistant CRC cells, and knockdown of miR-31 increased the chemosensitivity of 5-FU-resistant CRC cells. Furthermore, we demonstrated that ENST00000547547 reduced the chemoresistance of 5-FU via competitive binding to miR-31 in 5-FU-resistant CRC cell lines. Collectively, our findings revealed that ENST00000547547 reduced chemoresistance in 5-FU of 5-FU-resistant CRC cells through competitive binding to miR-31 and has the potential to serve as a therapeutic target in CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-31"}
{"PMID":26790446,"Year":2016,"Title":"Contribution of in vitro comparison of colorectal carcinoma cells from primary and metastatic lesions to elucidation of mechanisms of tumor progression and response to anticancer therapy.","Abstract":"Colorectal cancer has been a leading cause of cancer-related morbidity and mortality. For the research and individualization of therapy, primary cell lines of the colorectal cancer appear to be still an invaluable tool. We evaluated the differences in metastatic potential between four isolated primary colon cancer cells and cells derived from their lymph node metastasis. These results were compared with correspond immortalized cells-SW480 and SW620, respectively. The ability to migrate was tested using real-time measurement in xCELLigence system. Expressions of molecules involved in adhesion and invasion processes were examined using RT-PCR and western blot analysis. Furthermore, impact of cytotoxic effect of selected chemotherapeutics (irinotecan, oxaliplatin) and biological therapy (bevacizumab, cetuximab, panitumumab) was assessed by the WST assay. As expected, cell lines derived from lymph node migrated more aggressively and higher expression of adhesion molecules ICAM-1, EpCAM, and N-cadherin was detected. The expression of MMP-2 and -9 was elevated, on the other hand, in cell lines derived from primary tumor cancer cells as well as the expression of miR-21, miR-29a, and miR-200a. The most pronounced cytotoxic effect has been recorded with oxaliplatin and irinotecan (IC50 = 48.23 resp. 0.11 mug/ml), especially in cells originating from lymph node metastases. In total, comparison of isolated cell lines and immortalized cell lines has shown many similarities, as well as several differences. Adhesion/invasion molecules and several miRNAs, which play an important role in tumor development and the invasive and migratory behavior, could be a useful therapeutic target in malignant colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":30387187,"Year":2018,"Title":"miR-30a promoter variation contributes to the increased risk of colorectal cancer in an Iranian population.","Abstract":"Cytochrome P450 family 24 subfamily A member 1 (CYP24A1) gene is overexpressed in many cancers including colorectal cancer (CRC) and correlated with tumor invasion, lymph node metastasis, and the reduced overall survival. We predicted that miR-30a and miR-125a regulate the CYp24A1 gene expression. Therefore, we performed a case-control study using 800 individuals, including 389 patients with CRC and 411 noncancer controls to evaluate the association between miR-30a rs2222722 and miR-125a rs12976445 polymorphisms, located at in the promoter region, and the risk of sporadic CRC in an Iranian population. The genotyping assay for both polymorphisms was performed using Tetra-primer amplification refractory mutation systems polymerase chain reaction. The results indicated that the frequency of the miR-30a rs2222722 CT genotype was significantly different in the studied groups ( P = 0.0001; odds ratio [OR] = 1.9; 95% confidence interval [CI], 1.39-2.60). Also, a significant difference was observed under the dominant inheritance model ( P = 0.0001; OR = 1.8; 95% CI, 1.33-2.43). The frequency of the miR-30a rs2222722 T allele was significantly associated with increased CRC risk in the studied population ( P = 0.0019; OR = 1.47; 95% CI, 1.15-1.89). Taken together, our study provides preliminary evidence that the rs2222722 polymorphism increases the susceptibility to CRC in an Iranian population. Therefore, the affecting factors on CYP24A1 gene expression such as microRNAs can be considered as risk factors for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-125"}
{"PMID":23354160,"Year":2013,"Title":"Clinical significance of microRNA-93 downregulation in human colon cancer.","Abstract":"AIM: MicroRNA-93 (miR-93) has been shown to suppress proliferation and colony formation of colon cancer stem cells. The aim of this study was to examine the expression pattern and prognostic value of miR-93 in patients with colon cancer. MATERIALS AND METHODS: A quantitative real-time PCR analysis was carried out to detect the expression levels of miR-93 in 138 paired samples of tumoral and nontumoral colon tissues diagnosed with colon cancer. Associations of miR-93 expression with clinicopathological parameters and survival were also examined. RESULTS: miR-93 expression was significantly decreased in tumoral compared with nontumoral colon tissues (P<0.001). Low miR-93 expression was significantly correlated with advanced tumor stage (P=0.02), positive nodal metastasis (P=0.006), and positive distant metastases (P=0.01). In addition, Kaplan-Meier survival analysis by Cox regression showed that low miR-93 expression [hazard ratio (HR), 10.2; 95% confidence interval (CI), 1.9-42.8, P=0.003] was associated closely with poor overall survival in patients with colon cancer. Moreover, multivariate analysis showed that miR-93 decreased expression (HR, 4.3; 95% CI, 0.8-17.2, P=0.02), advanced tumor stage (HR, 3.1; 95% CI, 0.2-13.9, P=0.04), positive nodal metastasis (HR, 4.1; 95% CI, 0.7-16.8, P=0.02), and positive distant metastases (HR, 3.7; 95% CI, 0.5-14.1, P=0.03) were independent risk factors for overall survival in patients with colon cancer. CONCLUSION: Our data show for the first time that the downregulation of miR-93 was significantly correlated with unfavorable clinicopathologic features and short overall survival in patients with colon cancer, suggesting that decreased expression of miR-93 be used as a novel prognostic factor for this disease.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-93"}
{"PMID":28980150,"Year":2019,"Title":"Comparison of Circulating miRNAs Expression Alterations in Matched Tissue and Plasma Samples During Colorectal Cancer Progression.","Abstract":"MicroRNAs (miRNAs) have been found to play a critical role in colorectal adenoma-carcinoma sequence. MiRNA-specific high-throughput arrays became available to detect promising miRNA expression alterations even in biological fluids, such as plasma samples, where miRNAs are stable. The purpose of this study was to identify circulating miRNAs showing altered expression between normal colonic (N), tubular adenoma (ADT), tubulovillous adenoma (ADTV) and colorectal cancer (CRC) matched plasma and tissue samples. Sixteen peripheral plasma and matched tissue biopsy samples (N n = 4; ADT n = 4; ADTV n = 4; CRC n = 4) were selected, and total RNA including miRNA fraction was isolated. MiRNAs from plasma samples were extracted using QIAamp Circulating Nucleic Acid Kit (Qiagen). Matched tissue-plasma miRNA microarray experiments were conducted by GeneChip(R) miRNA 3.0 Array (Affymetrix). RT-qPCR (microRNA Ready-to-use PCR Human Panel I + II; Exiqon) was used for validation. Characteristic miRNA expression alterations were observed in comparison of AD and CRC groups (miR-149*, miR-3196, miR-4687) in plasma samples. In the N vs. CRC comparison, significant overexpression of miR-612, miR-1296, miR-933, miR-937 and miR-1207 was detected by RT-PCR (p < 0.05). Similar expression pattern of these miRNAs were observed using microarray in tissue pairs, as well. Although miRNAs were also found in circulatory system in a lower concentration compared to tissues, expression patterns slightly overlapped between tissue and plasma samples. Detected circulating miRNA alterations may originate not only from the primer tumor but from other cell types including immune cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-3196"}
{"PMID":27095441,"Year":2016,"Title":"MicroRNA-204 modulates colorectal cancer cell sensitivity in response to 5-fluorouracil-based treatment by targeting high mobility group protein A2.","Abstract":"MicroRNAs (miRNAs) are a conserved class of approximately 22 nucleotide RNAs that playing important roles in various biological processes including chemoresistance. Recently, many studies have revealed that miR-204 is significantly attenuated in colorectal cancer (CRC), suggesting that this miRNA may have a function in CRC. However, whether miR-204 modulates chemosensitivity to 5-fluorouracil (5-Fu) in colorectal cancer is still unclear. In our present study, we discuss this possibility and the potential mechanism exerting this effect. We identified high mobility group protein A2 (HMGA2) as a novel direct target of miR-204 and showed that miR-204 expression was decreased while HMGA2 expression was increased in CRC cell lines. Additionally, both MiR-204 overexpression and HMGA2 inhibition attenuated cell proliferation, whereas forced expression of HMGA2 partly restored the inhibitory effect of miR-204 on HCT116 and SW480 cells. Moreover, the miR-204/HMGA2 axis modulated the resistance of tumor cells to 5-Fu in HCT-116 and SW480 colon cancer cells via activation of the PI3K/AKT pathway. These results demonstrate that the miR-204/HMGA2 axis could play a vital role in the 5-Fu resistance of colon cancer cells. Taken together, our present study elucidated that miR-204 upregulated 5-Fu chemosensitivity via the downregulation of HMGA2 in colorectal cancer and provided significant insight into the mechanism of 5-Fu resistance in colorectal cancer patients. More importantly, our present study suggested that miR-204 has potential as a therapeutic strategy for 5-Fu-resistant colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-204"}
{"PMID":30076720,"Year":2018,"Title":"Restoration of miR-152 expression suppresses cell proliferation, survival, and migration through inhibition of AKT-ERK pathway in colorectal cancer.","Abstract":"BACKGROUND: MiR-152 has been reported as a tumor suppressor microRNA that is downregulated in a number of cancers, including colorectal cancer (CRC). A recent study suggested that miR-152 could be one of the key regulators of CRC. The aim of this study is to investigate the role of miR-152 in CRC and its mechanisms. METHODS: The pCMV-GPF-miR-152 vector was transfected into SW-480 and HCT-116 CRC cells via JetPEI transfection reagent. The stable miR-152-expressed cells were selected for the further experiment. To evaluate the effect of miR-152 on cell proliferation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed. Also, the effect of miR-152 on the survival of CRC cells was analyzed using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. The inhibitory effect of miR-152 on migration was assessed by wound healing scratch assay. Then, the proteins expression levels of protein kinase B (AKT), phosphorylated AKT (p-AKT), extracellular signal-regulated kinase (ERK), and phosphorylated ERK (p-ERK) were measured by the western blot analysis method. RESULTS: The result of MTT assay represented miR-152 could inhibit cell proliferation. The TUNEL assay showed miR-152 could induce apoptosis in CRC cells. The wound healing scratch assay showed that miR-152 replacement repressed cell migration in CRC cell lines compared to control groups. The result of protein expression by western blot analysis demonstrated that miR-152 could reduce AKT-p-AKT, and ERK-p-ERK ratio compared to control cells. CONCLUSION: Our results show that miR-152 has new anticancer and antimetastatic effect in CRC tissue. The current study showed that miR-152 could be a novel therapeutic small molecule to suppress CRC cell proliferation, survival, and migration by suppressing AKT-ERK signaling pathways.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-152"}
{"PMID":25450382,"Year":2014,"Title":"U6 is not a suitable endogenous control for the quantification of circulating microRNAs.","Abstract":"Recently, microRNAs have been detected in serum and plasma, and circulating microRNA (miRNA) profiles have now been associated with many diseases such as cancers and heart disease, as well as altered physiological states. Because of their stability and disease resistance, circulation miRNAs appear to be an ideal material for biomarkers of diseases and physiological states in blood. However, the lack of a suitable internal reference gene (internal reference miRNA) has hampered research and application of circulating miRNAs. Currently, U6 and miR-16 are the most common endogenous controls in the research of miRNAs in tissues and cells. We performed microarray-based serum miRNA profiling on the serum of 20 nasopharyngeal carcinoma patients and 20 controls to detect the expressions of U6 and miRNAs. Profiling was followed by real-time quantitative Polymerase Chain Reaction (qPCR) in 80 patients (20 each with gastric cancer, nasopharyngeal carcinoma, colorectal cancer, and breast cancer) and 30 non-cancerous controls. qPCR was also performed to detect miRNAs in serum with repeated freezing and thawing. The results of microarray showed that with the exception of U6, Ct values of miR-16, miR-24, miR-142-3p, miR-19b and miR-192 in serum samples of nasopharyngeal carcinoma were greater than control samples. The results of 110 cases showed large fluctuations in U6 expression. The difference between the greatest and the least levels of expression was 3.29 for delta Ct values, and 1.23 for miR-16. The expressions of U6, miR-16 and miR-24 in serum subjected to different freeze-thaw cycles showed that U6 expression gradually decreased after 1, 2, and 4 cycles of freezing and thawing, while the expression of miR-16 and miR-24 remained relatively stable. Collectively, our results suggested that U6 is unsuitable as an internal reference gene in the research of circulating miRNAs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-192"}
{"PMID":22850566,"Year":2012,"Title":"The rectal cancer microRNAome--microRNA expression in rectal cancer and matched normal mucosa.","Abstract":"PURPOSE: miRNAs play a prominent role in a variety of physiologic and pathologic biologic processes, including cancer. For rectal cancers, only limited data are available on miRNA expression profiles, whereas the underlying genomic and transcriptomic aberrations have been firmly established. We therefore, aimed to comprehensively map the miRNA expression patterns of this disease. EXPERIMENTAL DESIGN: Tumor biopsies and corresponding matched mucosa samples were prospectively collected from 57 patients with locally advanced rectal cancers. Total RNA was extracted, and tumor and mucosa miRNA expression profiles were subsequently established for all patients. The expression of selected miRNAs was validated using semi-quantitative real-time PCR. RESULTS: Forty-nine miRNAs were significantly differentially expressed (log(2)-fold difference >0.5 and P < 0.001) between rectal cancer and normal rectal mucosa. The predicted targets for these miRNAs were enriched for the following pathways: Wnt, TGF-beta, mTOR, insulin, mitogen-activated protein kinase, and ErbB signaling. Thirteen of these 49 miRNAs seem to be rectal cancer-specific, and have not been previously reported for colon cancers: miR-492, miR-542-5p, miR-584, miR-483-5p, miR-144, miR-2110, miR-652, miR-375, miR-147b, miR-148a, miR-190, miR-26a/b, and miR-338-3p. Of clinical impact, miR-135b expression correlated significantly with disease-free and cancer-specific survival in an independent multicenter cohort of 116 patients. CONCLUSION: This comprehensive analysis of the rectal cancer miRNAome uncovered novel miRNAs and pathways associated with rectal cancer. This information contributes to a detailed view of this disease. Moreover, the identification and validation of miR-135b may help to identify novel molecular targets and pathways for therapeutic exploitation.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-584"}
{"PMID":28289479,"Year":2017,"Title":"Colorectal adenoma and carcinoma specific miRNA profiles in biopsy and their expression in plasma specimens.","Abstract":"BACKGROUND: MiRNA expression markers are well characterized in colorectal cancer (CRC), but less is known about miRNA expression profiles in colorectal adenomas. Genome-wide miRNA and mRNA expression analyses were conducted through the colorectal adenoma dysplasia sequence. Furthermore, analysis of the expression levels of miRNAs in matched plasma samples was performed, focusing on biomarker candidates; miRNA and mRNA expression analyses were performed on colorectal biopsies and plasma samples (20 normals; 11 tubular and 9 tubulovillous adenomas; 20 colorectal carcinomas) by miRNA 3.0 and Human Transcriptome Array (Affymetrix) and validated by RT-qPCR. Microarray data were analyzed using Expression Console and mRNA targets were predicted using miRWALK 2.0. RESULTS: Based on microarray analysis, 447 miRNAs were expressed in tissue and 320 in plasma. Twelve were upregulated (miR-31, 8-fold p < 0.001) and 11 were downregulated (miR-10b 3-fold p < 0.001) in neoplastic lesions compared to normal group. Eleven miRNAs showed altered expression between adenoma subtypes (miR-183 2.8-fold change, p < 0.007). Expression level of 24 miRNAs differed between adenoma and CRC groups (including miR-196a, 3.5-fold). Three miRNAs (miR-31, miR-4506, miR-452*) were differentially expressed in adenoma compared to normal both in tissue and plasma samples. miRNA expression data were confirmed by RT-PCR both in plasma and matched tissue samples. CONCLUSIONS: MiRNAs showed characteristic expression changes during CRC development in tissue. miRNAs were also presented in plasma and positively correlated with matched tissue expression levels. The identified miRNA expression changes could be verified RT-PCR methods facilitating routine application.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-183"}
{"PMID":24297055,"Year":2014,"Title":"NOD2 expression is regulated by microRNAs in colonic epithelial HCT116 cells.","Abstract":"BACKGROUND: Crohn's disease (CD) is associated with defective sensing of pathogens in genetically susceptible individuals. Nucleotide-binding oligomerization domain containing 2 (NOD2) mutations in coding regions are strongly linked to CD pathogenesis. Our laboratory has reported that microRNAs (miRNAs) are differentially expressed in CD. However, miRNA regulation of NOD2 remains unknown. This study was designed to determine whether miRNAs regulate NOD2 expression as well as downstream nuclear factor kappaB activation and inflammatory responses in colonic epithelial HCT116 cells. METHODS: NOD2 and miRNA expression in stimulated HCT116 cells were assessed by quantitative reverse transcription-polymerase chain reaction. Regulation of NOD2 expression by miRNAs was determined by luciferase reporter construct assays and transfection of specific miRNA mimics. Regulation of NOD2 signaling and immune response by miRNAs was assessed by transfection of mimics followed by muramyl dipeptide stimulation. RESULTS: Muramyl dipeptide-induced increases in NOD2, interleukin-8, and CXCL3 expression were inversely associated with miRNA expression. Overexpression of miR-192, miR-495, miR-512, and miR-671 suppressed NOD2 expression, muramyl dipeptide-mediated NF-kappaB activation, and messenger RNA expressions of interleukin-8 and CXCL3 in HCT116 cells. A single-nucleotide polymorphism (rs3135500) located in the NOD2 3'-untranslated region significantly reduced miR-192 effects on NOD2 gene expression. CONCLUSIONS: To our knowledge, this is the first report demonstrating that miRNAs regulate NOD2 and its signaling pathway. Four miRNAs downregulate NOD2 expression, suppress NF-kappaB activity, and inhibit interleukin-8 and CXCL3 messenger RNA expression. Treatment of CD with miRNAs may represent a potential anti-inflammatory therapeutic strategy in CD patients with and without NOD2 gene mutations.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-192"}
{"PMID":28098901,"Year":2017,"Title":"Effect of evodiamine and berberine on the interaction between DNMTs and target microRNAs during malignant transformation of the colon by TGF-beta1.","Abstract":"The tissue microenvironment functions as a crucial player in carcinogenesis, and transforming growth factor-beta1 (TGF-beta1) within the microenvironment stimulates the formation of neoplasms. Using an in vitro model of malignancy induced by TGF-beta1, we assessed the effect of evodiamine and berberine on the interaction between DNA methyltransferases (DNMTs) and target microRNAs (miRNAs) in the model. Colon tissues from neonatal rats 7 days of age were cultured and malignancy was induced by TGF-beta1 in vitro for 48 h, and then the tissues were respectively treated with evodiamine and berberine for 24 h. Morphological alteration of tissues was observed by an inverted microscope, histological structures were observed using hematoxylin and eosin staining, and the expression levels of DNMTs and targeted miRNAs screened by bioinformatics software combined with Gene chip analysis in our previous study were detected by immunohistochemistry and quantified by real-time PCR. Twenty-four hours after treatment with TGF-beta1, expression levels of DNMT1, DNMT3A, DNMT3B and miR-152 (target DNMT1), miR-429 (target DNMT3A) and miR-29a (target DNMT3A/3B) were markedly decreased; however, after 48 h, the expression levels of DNMT1 and DNMT3A were significantly increased, but their target miRNAs were still decreased. After treatment with a DNMT inhibitor (5-Aza-dC), expression levels of the miRNAs were increased to a larger extent, but did not reach normal levels. After treatment with berberine and evodiamine for 24 h, respectively, increased expression of DNMT1, DNMT3A, DNMT3B and miR-152, miR-429, miR-29a was noted. In conclusion, the results of the present study suggest that miRNAs can also be post-transcriptionally regulated by their corresponding DNMTs and that berberine and evodiamine regulate the expression of these genes, which provides early epigenetic evidence for the prevention and therapy of colorectal cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-152"}
{"PMID":27013928,"Year":2016,"Title":"Time course analysis based on gene expression profile and identification of target molecules for colorectal cancer.","Abstract":"BACKGROUND: The study aimed to investigate the expression changes of genes in colorectal cancer (CRC) and screen the potential molecular targets. METHODS: The GSE37178 of mRNA expression profile including the CRC samples extracted by surgical resection and the paired normal samples was downloaded from Gene Expression Omnibus database. The genes whose expressions were changed at four different time points were screened and clustered using Mfuzz package. Then DAVID was used to perform the functional and pathway enrichment analysis for genes in different clusters. The protein-protein interaction (PPI) networks were constructed for genes in the clusters according to the STRING database. Furthermore, the related-transcription factors (TFs) and microRNAs (miRNAs) were obtained based on the resources in databases and then were combined with the PPI networks in each cluster to construct the integrated network containing genes, TFs and miRNAs. RESULTS: As a result, 314 genes were clustered into four groups. Genes in cluster 1 and cluster 2 showed a decreasing trend, while genes in cluster 3 and cluster 4 presented an increasing trend. Then 18 TFs (e.g., TCF4, MEF2C and FOS) and 18 miRNAs (e.g., miR-382, miR-217, miR-1184, miR-326 and miR-330-5p) were identified and three integrated networks for cluster 1, 3, and 4 were constructed. CONCLUSIONS: The results implied that expression of PITX2, VSNL1, TCF4, MEF2C and FOS are time-related and associated with CRC development, accompanied by several miRNAs including miR-382, miR-217, miR-21, miR-1184, miR-326 and miR-330-5p. All of them might be used as potential diagnostic or therapeutic target molecules for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-1184"}
{"PMID":31241203,"Year":2019,"Title":"Evaluation of fecal microRNA stability in healthy cats.","Abstract":"BACKGROUND: Gastrointestinal (GI) cancer accounts for 14% of feline malignancies. There is a great need for reliable noninvasive diagnostic biomarkers to reach a timely diagnosis and initiate treatment. Fecal microRNAs (miRNAs) could be such a biomarker and have shown great potential in colorectal screening in people but have yet to be investigated in cats. OBJECTIVES: We aimed to evaluate the presence and stability of feline fecal miRNA under different storage conditions (room temperature [RT], 4, and -20 degrees C) and to evaluate the expression levels of specific fecal miRNAs collected on three separate days (days 1, 4, and 7) in healthy cats. METHODS: Healthy cats were prospectively recruited. Fecal samples were collected, aliquoted, and stored for 24 hours at RT and then transferred to -20 degrees C, stored for 24 hours at 4 degrees C and then transferred to -20 degrees C, or were immediately placed at -20 degrees C on day 1 or at -20 degrees C on days 4 and 7 postcollection. Expression of 22 miRNAs was investigated using quantitative real-time PCR. RESULTS: Ten miRNA assays worked well, and one, let-7b, was used for normalization. No differences in miRNA expression were seen between the three storage temperatures for the nine miRNAs investigated. Only miR-26a showed a significant increase in expression between samples of days 1 and 7. The rest of the miRNAs levels were stable over time. CONCLUSIONS: Fecal miRNA can be isolated from healthy cats. The expression was stable at different temperatures and for most of the miRNAs over time. Prospective studies evaluating fecal miRNA as biomarkers in cats with GI neoplasia are warranted.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-26"}
{"PMID":21283757,"Year":2011,"Title":"The microbe-derived short chain fatty acid butyrate targets miRNA-dependent p21 gene expression in human colon cancer.","Abstract":"Colonic microbiota ferment non-absorbed dietary fiber to produce prodigious amounts of short chain fatty acids (SCFAs) that benefit the host through a myriad of metabolic, trophic, and chemopreventative effects. The chemopreventative effects of the SCFA butyrate are, in part, mediated through induction of p21 gene expression. In this study, we assessed the role of microRNA(miRNA) in butyrate's induction of p21 expression. The expression profiles of miRNAs in HCT-116 cells and in human sporadic colon cancers were assessed by microarray and quantitative PCR. Regulation of p21 gene expression by miR-106b was assessed by 3' UTR luciferase reporter assays and transfection of specific miRNA mimics. Butyrate changed the expression of 44 miRNAs in HCT-116 cells, many of which were aberrantly expressed in colon cancer tissues. Members of the miR-106b family were decreased in the former and increased in the latter. Butyrate-induced p21 protein expression was dampened by treatment with a miR-106b mimic. Mutated p21 3'UTR-reporter constructs expressed in HCT-116 cells confirmed direct miR-106b targeting. Butyrate decreased HCT-116 proliferation, an effect reversed with the addition of the miR-106b mimic. We conclude that microbe-derived SCFAs regulate host gene expression involved in intestinal homeostasis as well as carcinogenesis through modulation of miRNAs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-106"}
{"PMID":31423272,"Year":2019,"Title":"MicroRNA expression profiling in the colorectal normal-adenoma-carcinoma transition.","Abstract":"Colorectal adenoma is a major precursor to colorectal cancer. Investigating the alteration of microRNA (miRNA/miR) expression during the progression from normal colorectal tissue to adenoma, and finally to colorectal carcinoma may aid our understanding of the biological mechanisms of colorectal tumorigenesis. In the present study, the miRNA expression profiles of normal colorectal tissue, adenoma and colorectal carcinoma from 6 patients were evaluated using miRNA-sequencing. A total of 334 miRNAs were identified as differentially expressed. It was revealed that 34 miRNAs were upregulated in all 6 patients, including miR-135b-5p, miR-18a-5p and miR-29b-3p, and 28 miRNAs were downregulated, including miR-1-3p, miR-338-3p and miR-218-5p. Using bioinformatic analysis, the potential target genes of these 62 miRNAs were predicted and found to be enriched in 'transcription, DNA-dependent (GO:0006351)', 'signal transduction (GO:0007165)', 'small molecule metabolic process (GO:0044281)' 'PI3K/AKT signaling pathway (path ID:04151)' and 'MAPK signaling pathway (path ID:04010)'. The miRNA expression profiles identified in the present study may extend our understanding of the molecular mechanisms underlying colorectal tumorigenesis and promote novel perspectives for prevention, diagnosis and treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-1"}
{"PMID":28854245,"Year":2017,"Title":"miR-625-3p is upregulated in CD8+ T cells during early immune reconstitution after allogeneic stem cell transplantation.","Abstract":"Alloreactive CD8+ T-cells mediate the curative graft-versus-leukaemia effect, the anti-viral immunity and graft-versus-host-disease (GvHD) after allogeneic stem cell transplantation (SCT). Thus, immune reconstitution with CD8+ T-cells is critical for the outcome of patients after allogeneic SCT. Certain miRNAs such as miR-146a or miR-155 play an important role in the regulation of post-transplant immunity in mice. While some miRNAs e.g. miR-423 or miR-155 are regulated in plasma or full blood during acute GvHD also in man, the relevance and expression profile of miRNAs in T-cells after allogeneic SCT is unknown. miR-625-3p has recently been described to be overexpressed in colorectal malignancies where it promotes migration, invasion and apoptosis resistance. Since similar regulative functions in cancer and T-cells have been described for an increasing number of miRNAs, we assumed a role for the cancer-related miR-625-3p also in T-cells. Here, we studied miR-625-3p expression selectively in CD8+ T-cells both in vitro and during immune reconstitution after allogeneic SCT in man. T-cell receptor stimulation lead to miR-625-3p upregulation in human CD8+ T-cells in vitro. Maintenance of elevated miR-625-3p expression levels was dependent on ongoing T-cell proliferation and was abrogated by withdrawal of interleukin 2 or the mTOR inhibitor rapamycin. Finally, miR-625-3p expression was analyzed in human CD8+ T-cells purified from 137 peripheral blood samples longitudinally collected from 74 patients after allogeneic SCT. miR-625-3p expression was upregulated on day 25 and on day 45, i.e. during the early phase of CD8+ T-cell reconstitution after allogeneic SCT and subsequently declined with completion of CD8+ T-cell reconstitution until day 150. In conclusion, this study has shown for the first time that miR-625-3p is regulated in CD8+ T-cells during proliferation in vitro and during early immune reconstitution after allogeneic SCT in vivo. These results warrant further studies to identify the targets and function of miR-625-3p in CD8+ T-cells and to analyze its predictive value for an effective immune reconstitution.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-423"}
{"PMID":26824186,"Year":2016,"Title":"miR-143 or miR-145 overexpression increases cetuximab-mediated antibody-dependent cellular cytotoxicity in human colon cancer cells.","Abstract":"miR-143 and miR-145 are downregulated in colon cancer. Here, we tested the effect of restoring these miRNAs on sensitization to cetuximab in mutant KRAS (HCT116 and SW480) and wild-type KRAS (SW48) colon cancer cells. We evaluated cetuximab-mediated antibody-dependent cellular cytotoxicity (ADCC) and the modulation of signaling pathways involved in immune effector cell-mediated elimination of cancer cells. Stable miR-143 or miR-145 overexpression increased cell sensitivity to cetuximab, resulting in a significant increase of cetuximab-mediated ADCC independently of KRAS status. Importantly, HCT116 cells overexpressing these miRNAs triggered apoptosis in result of cetuximab-mediated ADCC, effected by peripheral blood mononuclear cells (p < 0.01). This was associated with increased apoptosis and caspase-3/7 activity, and reduced Bcl-2 protein expression (p < 0.01). In addition, caspase inhibition abrogated cetuximab-mediated ADCC in HCT116 cells overexpressing either miR-143 or miR-145 (p < 0.01). Furthermore, Bcl-2 silencing led to high level of cetuximab-mediated ADCC, compared to control siRNA (p < 0.05). Importantly, granzyme B inhibition, abrogated cetuximab-mediated ADCC, reducing caspase-3/7 activity (p < 0.01). Collectively, our data suggests that re-introduction of miR-143 or miR-145 may provide a new approach for development of therapeutic strategies to re-sensitize colon cancer cells to cetuximab by stimulating cetuximab-dependent ADCC to induce cell death.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-145"}
{"PMID":20797623,"Year":2010,"Title":"STAT3 activation of miR-21 and miR-181b-1 via PTEN and CYLD are part of the epigenetic switch linking inflammation to cancer.","Abstract":"A transient inflammatory signal can initiate an epigenetic switch from nontransformed to cancer cells via a positive feedback loop involving NF-kappaB, Lin28, let-7, and IL-6. We identify differentially regulated microRNAs important for this switch and putative transcription factor binding sites in their promoters. STAT3, a transcription factor activated by IL-6, directly activates miR-21 and miR-181b-1. Remarkably, transient expression of either microRNA induces the epigenetic switch. MiR-21 and miR-181b-1, respectively, inhibit PTEN and CYLD tumor suppressors, leading to increased NF-kappaB activity required to maintain the transformed state. These STAT3-mediated regulatory circuits are required for the transformed state in diverse cell lines and tumor growth in xenografts, and their transcriptional signatures are observed in colon adenocarcinomas. Thus, STAT3 is not only a downstream target of IL-6 but, with miR-21, miR-181b-1, PTEN, and CYLD, is part of the positive feedback loop that underlies the epigenetic switch that links inflammation to cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-181"}
{"PMID":25773836,"Year":2015,"Title":"MicroRNA expression profile in patients with stage II colorectal cancer: a Turkish referral center study.","Abstract":"BACKGROUND: There are increasing data about microRNAs (miRNA) in the literature, providing abundant evidence that they play important roles in pathogenesis and development of colorectal cancer. In this study, we aimed to investigate the miRNA expression profiles in surgically resected specimens of patients with recurrent and non-recurrent colorectal cancer. MATERIALS AND METHODS: The study population included 40 patients with stage II colorectal cancer (20 patients with recurrent tumors, and 20 sex and age matched patients without recurrence), who underwent curative colectomy between 2004 and 2011 without adjuvant therapy. Expression of 16 miRNAs (miRNA-9, 21, 30d, 31, 106a, 127, 133a, 133b, 135b, 143, 145, 155, 182, 200a, 200c, 362) was verified by quantitative real-time polymerase chain reaction (qRT-PCR) in all resected colon cancer tissue samples and in corresponding normal colonic tissues. Data analyses were carried out using SPSS 15 software. Values were statistically significantly changed in 40 cancer tissues when compared to the corresponding 40 normal colonic tissues (p<0.001). MiR-30d, miR-133a, miR-143, miR-145 and miR-362 expression was statistically significantly downregulated in 40 resected colorectal cancer tissue samples (p<0.001). When we compared subgroups, miRNA expression profiles of 20 recurrent cancer tissues were similar to all 40 cancer tissues. However in 20 non-recurrent cancer tissues, miR-133a expression was not significantly downregulated, moreover miR-133b expression was significantly upregulated (p<0.05). CONCLUSIONS: Our study revealed dysregulation of expression of ten miRNAs in Turkish colon cancer patients. These miRNAs may be used as potential biomarkers for early detection, screening and surveillance of colorectal cancer, with functional effects on tumor cell behavior.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-135"}
{"PMID":27111221,"Year":2016,"Title":"Aberrant DNA Methylation: Implications in Racial Health Disparity.","Abstract":"BACKGROUND: Incidence and mortality rates of colorectal carcinoma (CRC) are higher in African Americans (AAs) than in Caucasian Americans (CAs). Deficient micronutrient intake due to dietary restrictions in racial/ethnic populations can alter genetic and molecular profiles leading to dysregulated methylation patterns and the inheritance of somatic to germline mutations. MATERIALS AND METHODS: Total DNA and RNA samples of paired tumor and adjacent normal colon tissues were prepared from AA and CA CRC specimens. Reduced Representation Bisulfite Sequencing (RRBS) and RNA sequencing were employed to evaluate total genome methylation of 5'-regulatory regions and dysregulation of gene expression, respectively. Robust analysis was conducted using a trimming-and-retrieving scheme for RRBS library mapping in conjunction with the BStool toolkit. RESULTS: DNA from the tumor of AA CRC patients, compared to adjacent normal tissues, contained 1,588 hypermethylated and 100 hypomethylated differentially methylated regions (DMRs). Whereas, 109 hypermethylated and 4 hypomethylated DMRs were observed in DNA from the tumor of CA CRC patients; representing a 14.6-fold and 25-fold change, respectively. Specifically; CHL1, 4 anti-inflammatory genes (i.e., NELL1, GDF1, ARHGEF4, and ITGA4), and 7 miRNAs (of which miR-9-3p and miR-124-3p have been implicated in CRC) were hypermethylated in DNA samples from AA patients with CRC. From the same sample set, RNAseq analysis revealed 108 downregulated genes (including 14 ribosomal proteins) and 34 upregulated genes (including POLR2B and CYP1B1 [targets of miR-124-3p]) in AA patients with CRC versus CA patients. CONCLUSION: DNA methylation profile and/or products of its downstream targets could serve as biomarker(s) addressing racial health disparity.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-124"}
{"PMID":25174582,"Year":2014,"Title":"Angiopoietin-like protein 2 negatively regulated by microRNA-25 contributes to the malignant progression of colorectal cancer.","Abstract":"Angiopoietin-like protein 2 (ANGPTL2) is associated with tumor progression while dysregulation of its expression has been observed in various types of cancer. However, the expression and role of ANGPTL2 remain exclusive in colorectal cancer (CRC). In the present study, we determined the expression levels of ANGPTL2 in CRC tissues and cells. The roles of ANGPTL2 and miR-25 in the migration and invasion of CRC SW620 and HCT-116 cells were also investigated using transwell assays or scratch wound assays. The results showed that ANGPTL2 increased with metastatic progression. Increased ANGPTL2 and decreased microRNA-25 (miR-25) expression were found to coexist in CRC. The functional studies revealed that knockdown of ANGPTL2 reduced colony formation, and the invasive and migratory abilities of human CRC SW620 and HCT-116 cells. Similarly, overexpression of miR-25 resulted in reduced colony formation, invasion and migration in both cell lines. The overexpression of miR-25 led to a decreased ANGPTL2 mRNA and protein expression, whereas the downregulation of miR-25 resulted in increased ANGPTL2 mRNA and protein expression, in SW620 and HCT-116 cells. miR-25 directly targeted ANGPTL2 by binding to its 3'UTR, as determined by the dual luciferase reporter assay. To the best of our know-ledge, the results of this study suggest for the first time that the abnormal upregulation of ANGPTL2 in CRC is associated with miR-25 downregulation. Additionally, miR-25mediated ANGPTL2 promoted the malignant progression of CRC. The present study provides evidence supporting ANGPTL2 and miR-25 as diagnostic or therapeutic targets for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-25"}
{"PMID":27095166,"Year":2016,"Title":"miRs-134 and -370 function as tumor suppressors in colorectal cancer by independently suppressing EGFR and PI3K signalling.","Abstract":"Growth factor receptor signalling plays a central and critical role in colorectal cancer. Most importantly, the EGFR signalling cascade involving PI3K/AKT/mTOR and Raf/MEK/ERK pathways are particularly relevant, since they are commonly activated in several cancer entities, including colorectal cancer. In this study, we show that miRs-134 and -370 are both capable of regulating these pathways by targeting EGFR and PIK3CA. In three different colorectal cancer cell lines (DLD1, HCT-116 and RKO), suppression of EGFR and PIK3CA through the enhanced expression of miR-134 or -370 led to a suppression of the key molecules of the PI3K/AKT/mTOR pathway. Furthermore, overexpression of miR-134 or -370 resulted in a significant reduction of cell proliferation, colony formation, migration, invasion and in-vivo tumor growth and metastasis. Concurrent experiments with small interfering RNAs targeting the prime targets show that our selected miRNAs exert a greater functional influence and affect more downstream molecules than is seen with silencing of the individual proteins. Taken together, these data indicate that miRs-134 and -370 are potential tumour suppressor miRNAs and could play a fundamental role in suppressing colorectal cancer tumorigenesis through their ability to co-ordinately regulate EGFR signalling cascade by independently targeting EGFR and PIK3CA.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-134"}
{"PMID":23486085,"Year":2013,"Title":"miR-30a suppresses cell migration and invasion through downregulation of PIK3CD in colorectal carcinoma.","Abstract":"BACKGROUND/AIMS: MicroRNAs (miRNAs) play key roles in tumor metastasis. The aim of this study was to determine the regulation and function of miR-30a in colorectal carcinoma (CRC) metastasis. METHODS: The expression of miR-30a was detected in CRC cell lines and samples by qRT-PCR. The anti-metastatic effect of miR-30a was determined by both in vitro and in vivo assays. A luciferase reporter assay was performed to determine target association between miR-30a and phosphoinositide 3-kinase catalytic subunit delta (PIK3CD). RESULTS: miR-30a was significantly downregulated in highly metastatic CRC cell lines and metastatic tissues. Overexpression of miR-30a suppressed CRC cell migration and invasion in vitro and liver metastasis in vivo, whereas miR-30a deletion dramatically promoted cell migration and invasion. Further studies revealed that PIK3CD is a direct target of miR-30a as miR-30a bounds directly to the 3'-UTR of PIK3CD, subsequently reducing its expression. Similar to the restoring miR-30a expression, PIK3CD downregulation inhibited cell migration and invasion, whereas PIK3CD overexpression rescued the suppressive effect of miR-30a. Moreover, significant downregulation of miR-30a in metastatic CRC tissues was found to be inversely correlated with PIK3CD expression. Mechanistic studies revealed that miR-30a down-regulated the expression of key components of the Akt/mTOR pathway, whereas PIK3CD overexpression reversed this negative effect. CONCLUSION: Our findings indicate that miR-30a might function as a metastasis suppressor in CRC. miR-30a may be a potential therapeutic target to block CRC metastasis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-30"}
{"PMID":30138915,"Year":2018,"Title":"Prognostic Impact of miR-200 Family Members in Plasma and Exosomes from Tumor-Draining versus Peripheral Veins of Colon Cancer Patients.","Abstract":"OBJECTIVE: To evaluate the prognostic potential of expression levels of miR-200 family members (miR-200a, miR-200b, miR-200c, miR-429, miR-141) in plasma and exosomes from the tumor-draining vein (mesenteric vein [MV]) and peripheral vein (PV) of colon cancer (CC) patients. METHODS: We analyzed the expression of miR-200 family members in matched samples of MV and PV plasma from 50 resected patients with CC and correlated our findings with overall survival (OS). We also examined the content of these microRNAs in MV and PV exosomes. RESULTS: Expression levels were higher in MV than in PV (miR-200a, p < 0.001; miR-200b, p < 0.001; miR-429, p = 0.01; miR-200c, p = 0.05; miR-141, p = 0.05). Low levels of both miR-200c and miR-141 in MV plasma were associated with longer OS (p = 0.02). This association was maintained for the MV exosome cargo of miR-200c and miR-141 (p = 0.02). CONCLUSION: Our findings provide the first indication that expression levels of miR-200c and miR-141 in MV plasma can identify CC patients with poor prognosis. In addition, our results lend further support to the premise that tumor-draining veins constitute a better source of biomarkers than do PVs.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-200"}
{"PMID":25216407,"Year":2014,"Title":"MicroRNA-185 suppresses growth and invasion of colon cancer cells through inhibition of the hypoxiainducible factor-2alpha pathway in vitro and in vivo.","Abstract":"MicroRNAs (miRs) are small noncoding RNAs with regulatory roles, which are involved in a broad spectrum of physiological and pathological processes, including cancer development and progression. However, the function of miR185 in the development of human colon cancer has not yet been investigated. In this study, the association between miR185 expression and the clinicopathological characteristics of patients with colon cancer was analyzed using quantitative polymerase chain reaction (qPCR). Using a gainoffunction approach, the effects of miR185 overexpression on the expression of hypoxiainducible factor2alpha (HIF2alpha), proliferating cell nuclear antigen (PCNA) and matrix metallopeptidase2 (MMP2) were investigated in SW620 colon cancer cells using qPCR and western blotting. Functional analysis of cellular proliferative activities, by MTT assay, and invasive potential, by Transwell assay, was conducted on SW620 cells expressing low levels of miR185. miR185 was found to be significantly downregulated in cancer tissues compared with adjacent noncancerous tissues, and was negatively correlated with lymph node metastasis of colon cancer (P<0.001). miR185 overexpression in vitro impeded cellular proliferation and invasive potential with reduced expression of HIF2alpha, PCNA and MMP2 in SW620 cells transfected with an miR185 mimic. In addition, the tumor volumes in SW620 subcutaneous nude mouse models treated with miR185 were significantly smaller than those of the control group. In conclusion, these findings indicate that miR185 as a tumor suppressor may affect the development of colon cancer cells via inhibition of HIF2alpha signaling, suggesting that miR185 may serve as a potential therapeutic target in cancer treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-185"}
{"PMID":27081702,"Year":2016,"Title":"Serum miR-125b is a non-invasive predictive biomarker of the pre-operative chemoradiotherapy responsiveness in patients with rectal adenocarcinoma.","Abstract":"BACKGROUND: Therapeutic management of Locally Advanced Rectal Cancer (LARC) involves pre-operative chemoradiotherapy (pCRT) followed by surgery. However, after pCRT the complete pathological response is approximately 20%, whereas in 20 to 40% of patients the response is poor or absent. METHODS: Cancer biopsy specimens (n= 38) and serum samples (n= 34) obtained before pCRT from 38 LARC patients were included in the study. Patients were classified in responders (R, tumor regression grade [TRG] 1-2; n= 16) and non-responders (NR, TRG 3-5; n= 22) according to the pathological response observed upon surgery. We performed miRNA microarrays analysis on biopsy specimens, and validated the selected candidates both by qRT-PCR (tissue and serum) and by in situ hybridization (tissue, miR-125b) analyses. RESULTS: Eleven miRNAs were significantly different between R and NR (miR-154, miR-409-3p, miR-127-3p, miR-214*, miR-299-5p and miR-125b overexpressed in NR; miR-33a, miR-30e, miR-338-3p, miR-200a and miR-378 decreased). In particular, miR-125b resulted to be the best candidate to discriminate the two groups (AUC of 0.9026; 95% CI, 0.7618-1.043). Additionally, miR-125b serum levels were significantly overexpressed in NR patients compared to R (p-value=0.0087), with an excellent discriminating power (AUC of 0.782; 95% CI, 0.6123-0.9518). CONCLUSIONS: The obtained results further support the clinical impact of miRNA analysis. High miR-125b expression in tissue and serum were associated with a poor treatment response in LARC patients, therefore miR-125b could be considered as a possible novel non-invasive biomarker of response in LARC treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-33"}
{"PMID":27632639,"Year":2017,"Title":"Plasma miR-122 and miR-200 family are prognostic markers in colorectal cancer.","Abstract":"Circulating microRNAs (miRNAs) have been proposed as minimally invasive prognostic markers for various types of cancers, including colorectal cancer (CRC), the third most diagnosed cancer worldwide. We aimed to evaluate the levels of circulating miRNAs that might serve as markers for CRC prognosis and survival. We included plasma samples of 543 CRC patients with stage I-IV disease from a population-based study carried out in Germany. After comprehensive evaluation of current literature, 95 miRNAs were selected and measured with Custom TaqMan(R) Array MicroRNA Cards. Plasma samples of non-metastatic and metastatic colon cancer patients, each group consisting of ten patients with 'good' and ten patients with 'bad' prognosis were screened. Identified candidate miRNAs were further validated by RT-qPCR in the whole study cohort. The association of the miRNA levels with patients' survival and the prognostic subtypes was analyzed with uni- and multivariate logistic regression and Cox proportional hazards regression models. Increased miR-122 levels were associated with a 'bad' prognostic subtype in metastatic CRC (Odds ratio: 1.563, 95% confidence interval (CI): 1.038-2.347) and a shorter relapse-free survival and overall survival for non-metastatic (Hazard ratio (HR): 1.370, 95% CI: 1.028-1.825; HR: 1.353, 95% CI: 1.002-1.828) and metastatic (HR: 1.264, 95% CI: 1.050-1.520; HR: 1.292, 95% CI: 1.078-1.548) CRC patients. Additionally, several members of the miR-200 family showed associations with patients' prognosis and correlations to clinicopathological characteristics. The here identified miRNA markers, miR-122 and the miR-200 family members, could be of use in the development of a multi-marker blood test for CRC prognosis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-200"}
{"PMID":26522916,"Year":2015,"Title":"Heterogeneity of miR-10b expression in circulating tumor cells.","Abstract":"Circulating tumor cells (CTCs) in the blood of cancer patients are recognized as important potential targets for future anticancer therapies. As mediators of metastatic spread, CTCs are also promising to be used as 'liquid biopsy' to aid clinical decision-making. Recent work has revealed potentially important genotypic and phenotypic heterogeneity within CTC populations, even within the same patient. MicroRNAs (miRNAs) are key regulators of gene expression and have emerged as potentially important diagnostic markers and targets for anti-cancer therapy. Here, we describe a robust in situ hybridization (ISH) protocol, incorporating the CellSearch((R)) CTC detection system, enabling clinical investigation of important miRNAs, such as miR-10b on a cell by cell basis. We also use this method to demonstrate heterogeneity of such as miR-10b on a cell-by-cell basis. We also use this method to demonstrate heterogeneity of miR-10b in individual CTCs from breast, prostate and colorectal cancer patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-10"}
{"PMID":22348113,"Year":2012,"Title":"Computational analysis of mRNA expression profiles identifies microRNA-29a/c as predictor of colorectal cancer early recurrence.","Abstract":"Colorectal cancer (CRC) is one of the leading malignant cancers with a rapid increase in incidence and mortality. The recurrences of CRC after curative resection are sometimes unavoidable and often take place within the first year after surgery. MicroRNAs may serve as biomarkers to predict early recurrence of CRC, but identifying them from over 1,400 known human microRNAs is challenging and costly. An alternative approach is to analyze existing expression data of messenger RNAs (mRNAs) because generally speaking the expression levels of microRNAs and their target mRNAs are inversely correlated. In this study, we extracted six mRNA expression data of CRC in four studies (GSE12032, GSE17538, GSE4526 and GSE17181) from the gene expression omnibus (GEO). We inferred microRNA expression profiles and performed computational analysis to identify microRNAs associated with CRC recurrence using the IMRE method based on the MicroCosm database that includes 568,071 microRNA-target connections between 711 microRNAs and 20,884 gene targets. Two microRNAs, miR-29a and miR-29c, were disclosed and further meta-analysis of the six mRNA expression datasets showed that these two microRNAs were highly significant based on the Fisher p-value combination (p = 9.14 x 10(-9) for miR-29a and p = 1.14 x 10(-6) for miR-29c). Furthermore, these two microRNAs were experimentally tested in 78 human CRC samples to validate their effect on early recurrence. Our empirical results showed that the two microRNAs were significantly down-regulated (p = 0.007 for miR-29a and p = 0.007 for miR-29c) in the early-recurrence patients. This study shows the feasibility of using mRNA profiles to indicate microRNAs. We also shows miR-29a/c could be potential biomarkers for CRC early recurrence.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":29374690,"Year":2018,"Title":"MicroRNA Expression in KRAS- and BRAF-mutated Colorectal Cancers.","Abstract":"BACKGROUND/AIM: KRAS and BRAF are two genes commonly mutated in colorectal cancer (CRC). Even though BRAF is a downstream target of KRAS in the MAPK signalling pathway, KRAS- and BRAF-mutated CRCs are found to display several different clinical and histopathological features. We investigated whether a differential expression of microRNAs (miRNAs) could explain the clinicopathological differences seen between KRAS- and BRAF-mutated CRCs. MATERIALS AND METHODS: Using a PCR array, we analyzed the expression of 84 different miRNAs in CRC cell lines wild-type in KRAS and BRAF, or mutated in KRAS or BRAF. RESULTS: Ten miRNAs were selected for further analyses in tumor tissue specimens (let-7a, let-7i, miR-10a, miR-10b, miR-31, miR-100, miR-181a, miR-181b, miR-372, and miR-373). BRAF-mutated tumors were found to express significantly higher levels of miR-31 as well as significantly lower levels of miR-373, compared to wild-type tumors. CONCLUSION: Our results suggest that KRAS- and BRAF-mutated CRCs may have different miRNA signatures compared to CRC tumors wild-type in KRAS and BRAF. However, no difference in expression levels between KRAS- and BRAF-mutated tumors was evident for the miRNAs analyzed in this study.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-373"}
{"PMID":26905585,"Year":2016,"Title":"A functional polymorphism in lnc-LAMC2-1:1 confers risk of colorectal cancer by affecting miRNA binding.","Abstract":"Genome-wide association studies (GWASs) have identified multiple susceptibility loci of colorectal cancer (CRC), however, causative polymorphisms have not been fully elucidated. Long non-coding RNAs (lncRNAs) are a recently discovered class of non-protein coding RNAs that involved in a wide variety of biological processes. We hypothesized that single nucleotide polymorphisms (SNPs) in lncRNA may associate with the CRC risk by influencing lncRNA functions. To evaluate the effects of SNPs on CRC susceptibility in Chinese populations, we first screened out all potentially functional SNPs in exons of lncRNAs located in CRC susceptibility loci identified by GWAS. Eight SNPs were selected and genotyped in 875 CRC cases and 855 controls and replicated in an independent case-control study consisting of 768 CRC cases and 768 controls. Analyses showed that CG and GG genotypes of the rs2147578 were significantly associated with increased risk for CRC occurrence in both case-control studies [combined analysis OR = 1.29; 95% confidence interval (CI) = 1.11-1.51, P = 0.001] compared to the rs2147578 CC genotype. Bioinformatics analyses showed that rs2147578 is located in the transcript of lnc-LAMC2-1:1 and could influence the binding of lnc-LAMC2-1:1/miR-128-3p. Further luciferase reporter assays demonstrated that the construct with the risk rs2147578G allele had relatively high expression activity compared with that of the rs2147578C allele. Expression quantitative trait loci analyses also showed that rs2147578 is correlated with the expression of a well established oncogene LAMC2 (laminin subunit gamma 2). These findings indicated that rs2147578 in lnc-LAMC2-1:1 might be a genetic modifier for the development of CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-128"}
{"PMID":29589310,"Year":2018,"Title":"RT-qPCR for Fecal Mature MicroRNA Quantification and Validation.","Abstract":"By routinely and systematically being able to perform quantitative stem-loop reverse transcriptase (RT) followed by TaqMan(R) minor-groove binding (MGB) probe, real-time quantitative PCR analysis on exfoliated enriched colonocytes in stool, using human (Homo sapiens, hsa) micro(mi)RNAs to monitor changes of their expression at various stages of colorectal (CRC) progression, this method allows for the reliable and quantitative diagnostic screening of colon cancer (CC). Although the expression of some miRNA genes tested in tissue shows less variability in normal or cancerous patients than in stool, the noninvasive stool by itself is well suited for CC screening. An miRNA approach using stool promises to offer more sensitivity and specificity than currently used genomic, methylomic, or proteomic methods for CC screening.To present an application of employing miRNAs as diagnostic markers for CC screening, we carried out global microarray expression studies on stool colonocytes isolated by paramagnetic beads, using Affymetrix GeneChip miRNA 3.0 Array, to select a panel of miRNAs for subsequent focused semiquantitative PCR analysis studies. We then conducted a stem-loop RT-TaqMan(R) MGB probes, followed by a modified real-time qPCR expression study on 20 selected miRNAs for subsequent validation of the extracted immunocaptured total small RNA isolated from stool colonocytes. Results showed 12 miRNAs (miR-7, miR-17, miR-20a, miR-21, miR-92a, miR-96, miR-106a, miR-134, miR-183, miR-196a, miR-199a-3p, and miR214) to have an increased expression in stool of CC patients, and that later TNM stages exhibited more increased expressions than adenomas, while 8 miRNAs (miR-9, miR-29b, miR-127-5p, miR-138, miR-143, miR-146a, miR-222, and miR-938) showed decreased expressions in stool of CC patients, which becomes more pronounced as the cancer progresses from early to late TNM stages (0-IV).","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-938"}
{"PMID":26739063,"Year":2016,"Title":"LMTK3 escapes tumour suppressor miRNAs via sequestration of DDX5.","Abstract":"Lemur tyrosine kinase-3 (LMTK3) plays an important role in cancer progression and is associated with breast, lung, gastric and colorectal cancer. MicroRNAs (miRNAs) are small endogenous non-coding RNAs that typically repress target genes at post-transcriptional level and have an important role in tumorigenesis. By performing a miRNA expression profile, we identified a subset of miRNAs modulated by LMTK3. We show that LMTK3 induces miR-34a, miR-196-a2 and miR-182 levels by interacting with DEAD-box RNA helicase p68 (DDX5). LMTK3 binds via DDX5 to the pri-miRNA of these three mature miRNAs, thereby sequestrating them from further processing. Ectopic expression of miR-34a and miR-182 in LMTK3-overexpressing cell lines (MCF7-LMTK3 and MDA-MB-231-LMTK3) inhibits breast cancer proliferation, invasion and migration. Interestingly, miR-34a and miR-182 directly bind to the 3'UTR of LMTK3 mRNA and consequently inhibit both its stability and translation, acting as tumour suppressor-like miRNAs. In aggregate, we show that LMTK3 is involved in miRNA biogenesis through modulation of the Microprocessor complex, inducing miRNAs that target LMTK3 itself.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":22992310,"Year":2012,"Title":"Expression of miR-34 is lost in colon cancer which can be re-expressed by a novel agent CDF.","Abstract":"BACKGROUND: Colorectal Cancer (CRC) is one of the leading causes of death worldwide. Numerous cellular events, including deregulated expression of microRNAs (miRNAs), specifically the family of miR-34 consisting of miR-34a, b and c, is known to regulate the processes of growth and metastasis. METHODS: We evaluated the expression of miR-34 in formalin-fixed paraffin-embedded (FFPE) human colon cancer tissue specimens compared to normal colonic mucosa. Moreover, we also assessed the expression of miR-34 in colon cancer cell lines treated with our newly developed synthetic analogue of curcumin referred as difluorinated curcumin (CDF) compared to well known inhibitor of methyl transferase. RESULTS: We found that the expression of miR-34a and miR-34c was down-regulated in colon cancer specimens compared to normal colonic mucosa and the loss of expression was also consistent with data from colon cancer cell lines. This down-regulation was attributed to promoter hypermethylation, because we found that the treatment of colon cancer cells with 5-aza-2 -deoxycytidine, a methyltransferase inhibitor, markedly induced the levels of miR-34a and miR-34c expression. Likewise, CDF was very effective in the re-expression of miR-34a and miR-34c, which was consistent with inhibition of cell growth of both chemo-sensitive and chemo-resistant colon cancer cells. The re-expression of miR-34 led to a marked reduction in the expression of its target gene, Notch-1. CONCLUSION: The loss of expression of miR-34 in colon cancer is in part due to promoter hypermethylation of miR-34, which can be re-expressed with our novel agent CDF, suggesting that CDF could be a novel demethylating agent for restoring the expression of miR-34 family, and thus CDF could become a newer therapeutic agent for the treatment of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":26913609,"Year":2016,"Title":"Proteomic screening identifies calreticulin as a miR-27a direct target repressing MHC class I cell surface exposure in colorectal cancer.","Abstract":"Impairment of the immune response and aberrant expression of microRNAs are emerging hallmarks of tumour initiation/progression, in addition to driver gene mutations and epigenetic modifications. We performed a preliminary survey of independent adenoma and colorectal cancer (CRC) miRnoma data sets and, among the most dysregulated miRNAs, we selected miR-27a and disclosed that it is already upregulated in adenoma and further increases during the evolution to adenocarcinoma. To identify novel genes and pathways regulated by this miRNA, we employed a differential 2DE-DIGE proteome analysis. We showed that miR-27a modulates a group of proteins involved in MHC class I cell surface exposure and, mechanistically, demonstrated that calreticulin is a miR-27a direct target responsible for most downstream effects in epistasis experiments. In vitro miR-27a affected cell proliferation and angiogenesis; mouse xenografts of human CRC cell lines expressing different miR-27a levels confirmed the protein variations and recapitulated the cell growth and apoptosis effects. In vivo miR-27a inversely correlated with MHC class I molecules and calreticulin expression, CD8(+) T cells infiltration and cytotoxic activity (LAMP-1 exposure and perforin release). Tumours with high miR-27a, low calreticulin and CD8(+) T cells' infiltration were associated with distant metastasis and poor prognosis. Our data demonstrate that miR-27a acts as an oncomiRNA, represses MHC class I expression through calreticulin downregulation and affects tumour progression. These results may pave the way for better diagnosis, patient stratification and novel therapeutic approaches.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-27"}
{"PMID":30944658,"Year":2019,"Title":"Association between TP53 genetic polymorphisms and the methylation and expression of miR-34a, 34b/c in colorectal cancer tissues.","Abstract":"Colorectal cancer (CRC) is one of the most common types of cancers, as evidenced by the >1.2 million patient diagnoses and 600,000 mortalities globally each year. Recently, the microRNA (miR/miRNA)-34 miRNA precursor family was revealed to participate in the tumor protein (TP)-53 pathway, which is frequently involved in CRC. Furthermore, the expression of miR-34 is reportedly regulated by DNA methylation. Accordingly, the present study investigated the correlation between the methylation status of miR-34 miRNAs and miR-34 expression in paired CRC tumor and normal tissues. The methylation status of miR-34a and miR-34b/c was determined using the MethyLight assay, and the expression of miR-34a and miR-34b/c in the same paired tissues was analyzed by reverse transcription-quantitative polymerase chain reaction. The results revealed significantly elevated miR-34a (P=0.012) and miR-34b/c (P<0.0001) methylation levels in tumor tissues when compared with normal tissues, whereas only the expression of miR-34b/c differed (P=0.005) between the paired tissues. In addition, an association between TP53 haplotypes and miR-34 family expression levels was observed. The miR-34a methylation levels in the TP53 PIN A1A1 (48.56+/-36.49) and TP53 MSP GG (49.00+/-36.44) genotypes were increased in the tumor tissues when compared with normal tissues. In conclusion, it was determined that miR-34 promoter methylation and TP53 polymorphisms may be associated with CRC pathogenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":28980150,"Year":2019,"Title":"Comparison of Circulating miRNAs Expression Alterations in Matched Tissue and Plasma Samples During Colorectal Cancer Progression.","Abstract":"MicroRNAs (miRNAs) have been found to play a critical role in colorectal adenoma-carcinoma sequence. MiRNA-specific high-throughput arrays became available to detect promising miRNA expression alterations even in biological fluids, such as plasma samples, where miRNAs are stable. The purpose of this study was to identify circulating miRNAs showing altered expression between normal colonic (N), tubular adenoma (ADT), tubulovillous adenoma (ADTV) and colorectal cancer (CRC) matched plasma and tissue samples. Sixteen peripheral plasma and matched tissue biopsy samples (N n = 4; ADT n = 4; ADTV n = 4; CRC n = 4) were selected, and total RNA including miRNA fraction was isolated. MiRNAs from plasma samples were extracted using QIAamp Circulating Nucleic Acid Kit (Qiagen). Matched tissue-plasma miRNA microarray experiments were conducted by GeneChip(R) miRNA 3.0 Array (Affymetrix). RT-qPCR (microRNA Ready-to-use PCR Human Panel I + II; Exiqon) was used for validation. Characteristic miRNA expression alterations were observed in comparison of AD and CRC groups (miR-149*, miR-3196, miR-4687) in plasma samples. In the N vs. CRC comparison, significant overexpression of miR-612, miR-1296, miR-933, miR-937 and miR-1207 was detected by RT-PCR (p < 0.05). Similar expression pattern of these miRNAs were observed using microarray in tissue pairs, as well. Although miRNAs were also found in circulatory system in a lower concentration compared to tissues, expression patterns slightly overlapped between tissue and plasma samples. Detected circulating miRNA alterations may originate not only from the primer tumor but from other cell types including immune cells.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-933"}
{"PMID":20413677,"Year":2010,"Title":"Association of microRNA expression with microsatellite instability status in colorectal adenocarcinoma.","Abstract":"MicroRNAs (miRNA), small noncoding RNAs, are potential diagnostic and prognostic markers, as well as therapeutic targets. miRNA profiles of colorectal carcinomas have not been studied extensively in the context of microsatellite instability (MSI) status. We therefore evaluated 55 paired colorectal adenocarcinomas (CRC) and non-neoplastic mucosa samples using a panel of 24 miRNAs selected by literature review and prior studies in our laboratory. Stem-loop reverse transcriptase quantitative (real-time) polymerase chain reaction assays were done on RNA extracted from formalin-fixed, paraffin-embedded tissue of resection specimens. When miRNA expression was compared with clinicopathologic features and MSI status, eleven miRNAs (miR-183, -31, -20, -25, -92, -93, -17, -135a, -203, -133b, and -223) were over-expressed in CRC relative to mucosa, and nine (miR-192, -215, -26b, -143, -145, -191, -196a, -16, and let-7a) were under-expressed in CRC. Relative expression of miR-92, -223, -155, -196a, -31, and -26b were significantly different among MSI subgroups, and miR-31 and miR-223 were overexpressed in CRC of patients with hereditary non-polyposis colorectal cancer syndrome (Lynch syndrome). Our findings indicate that miRNA expression in CRC is associated with MSI subgroups, including low MSI and HNPCC-associated cancers, and that miRNAs may have posttranscriptional gene regulatory roles in these MSI subgroups and possible effects on the clinicopathologic and biomarker characteristics.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-203"}
{"PMID":31438886,"Year":2019,"Title":"CircRNA CBL.11 suppresses cell proliferation by sponging miR-6778-5p in colorectal cancer.","Abstract":"BACKGROUND: Radiotherapy (RT) is considered an important therapeutic strategy in the fight against colorectal cancer (CRC). However, the existence of some radioresistance factors becomes the main challenge for the RT. Recently, non-coding RNAs (ncRNAs) have shown an important role in modulating cancer cell responses to ionizing radiation (IR). It is therefore of great significance to elucidate the exact mechanisms of ncRNAs in IR-mediated responses to CRC. METHODS: Microarrays were used to identify specific miRNAs that may be altered in response to IR. Bioinformatics, luciferase reporter analyses were used to explore the targets of miR-6778-5p. CircRNA CBL.11 was identified to bind with miR-6778-5p by bioinformatic analysis, AGO2 immunoprecipitation and biotinylated RNA pull-down assay. Functional experiments, including CCK-8 assay, cell colony formation assay and EdU incorporation were conducted to investigate the biological roles of miR-6778-5p and circular RNA CBL.11. RESULTS: MiR-6778-5p was suppressed in CRC cells after irradiation. Results of functional experiments indicated that miR-6778-5p promoted the proliferation of CRC cells. Luciferase reporter analyses showed that YWHAE was a target of miR-6778-5p, which mediated the function of miR-6778-5p in the proliferation of CRC cells via the p53 pathway. Furthermore, we have noticed that after carbon ion irradiation, circRNA CBL.11 was increased in CRC cells and could function as a competing endogenous RNA (ceRNA) to regulate YWHAE expression by sponging miR-6778-5p, resulting in regulation the proliferation of CRC cells. CONCLUSION: CircRNA CBL.11 may play an important role in improving the efficacy of carbon ion RT against CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-6778"}
{"PMID":26747707,"Year":2016,"Title":"Transcriptional Regulation of miR-31 by Oncogenic KRAS Mediates Metastatic Phenotypes by Repressing RASA1.","Abstract":"UNLABELLED: Activating KRAS mutations are nearly ubiquitous in pancreatic cancer occurring in more than 95% of clinical cases. miRNAs are small noncoding RNAs that regulate gene expression by binding sequences within the 3'UTRs of target mRNAs. An integral role for miRNAs in cancer pathogenesis is well established; however, the role of miRNAs in KRAS-mediated tumorigenesis is poorly characterized. Here it is demonstrated that expression of miR-31 is coupled to the expression of oncogenic KRAS and activity of the MAPK pathway. miR-31 is highly expressed in patient-derived xenografts and a panel of pancreatic and colorectal cancer cells harboring activating KRAS mutations. The miR-31 host gene is a large noncoding RNA that correlates with miR-31 expression and enabled identification of the putative miR-31 promoter. Using luciferase reporters, a minimal RAS-responsive miR-31 promoter was found to drive robust luciferase activity dependent on expression of mutant KRAS and the transcription factor ELK1. Furthermore, ELK1 interacts directly with the endogenous miR-31 promoter in a MAPK-dependent manner. Expression of enforced miR-31 significantly enhanced invasion and migration of multiple pancreatic cancer cells resulting from the activation of RhoA through regulation of the miR-31 target gene RASA1. Importantly, acute knockdown of RASA1 phenocopied enforced miR-31 expression on the migratory behavior of pancreatic cancer cells through increased RhoA activation. IMPLICATIONS: Oncogenic KRAS can activate Rho through the miR-31-mediated regulation of RASA1 indicating miR-31 acts as a KRAS effector to modulate invasion and migration in pancreatic cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-31"}
{"PMID":30083271,"Year":2018,"Title":"Carcinoma-associated fibroblasts promote the stemness and chemoresistance of colorectal cancer by transferring exosomal lncRNA H19.","Abstract":"Long non-coding RNAs (lncRNAs) are involved in the pathology of various tumors, including colorectal cancer (CRC). The crosstalk between carcinoma- associated fibroblasts (CAFs) and cancer cells in the tumor microenvironment promotes tumor development and confers chemoresistance. In this study, we further investigated the underlying tumor-promoting roles of CAFs and the molecular mediators involved in these processes. Methods: The AOM/DSS-induced colitis-associated cancer (CAC) mouse model was established, and RNA sequencing was performed. Small interfering RNA (siRNA) sequences were used to knock down H19. Cell apoptosis was measured by flow cytometry. SW480 cells with H19 stably knocked down were used to establish a xenograft model. The indicated protein levels in xenograft tumor tissues were confirmed by immunohistochemistry assay, and cell apoptosis was analyzed by TUNEL apoptosis assay. RNA-FISH and immunofluorescence assays were performed to assess the expression of H19 in tumor stroma and cancer nests. The AldeRed ALDH detection assay was performed to detect intracellular aldehyde dehydrogenase (ALDH) enzyme activity. Isolated exosomes were identified by transmission electron microscopy, nanoparticle tracking and Western blotting. Results: H19 was highly expressed in the tumor tissues of CAC mice compared with the expression in normal colon tissues. The up-regulation of H19 was also confirmed in CRC patient samples at different tumor node metastasis (TNM) stages. Moreover, H19 was associated with the stemness of colorectal cancer stem cells (CSCs) in CRC specimens. H19 promoted the stemness of CSCs and increased the frequency of tumor-initiating cells. RNA-FISH showed higher expression of H19 in tumor stroma than in cancer nests. Of note, H19 was enriched in CAF-derived conditioned medium and exosomes, which in turn promoted the stemness of CSCs and the chemoresistance of CRC cells in vitro and in vivo. Furthermore, H19 activated the beta-catenin pathway via acting as a competing endogenous RNA sponge for miR-141 in CRC, while miR-141 significantly inhibited the stemness of CRC cells. Conclusion: CAFs promote the stemness and chemoresistance of CRC by transferring exosomal H19. H19 activated the beta-catenin pathway via acting as a competing endogenous RNA sponge for miR-141, while miR-141 inhibited the stemness of CRC cells. Our findings indicate that H19 expressed by CAFs of the colorectal tumor stroma contributes to tumor development and chemoresistance.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-141"}
{"PMID":28731158,"Year":2017,"Title":"The long non-coding RNA SNHG3 functions as a competing endogenous RNA to promote malignant development of colorectal cancer.","Abstract":"Accumulating evidence has revealed that aberrantly expressed long non-coding transcripts are involved in the development and progression of colorectal cancer (CRC). Small nucleolar RNA host gene 3 (SNHG3) is a newly identified lncRNA, and little is known about its clinical significance and biological functions in the development of CRC. In the present study, we found that the expression of SNHG3 was significantly upregulated in CRC, and upregulation of SNHG3 predicted poor prognosis for patients with CRC as determined through analysis of the data obtained from TCGA database. Gain-of function and loss-of function assays revealed that SNHG3 markedly promoted cellular proliferation of CRC cells. Gene Set Enrichment Analysis (GSEA) suggested that high expression of SNHG3 was positively associated with c-Myc and its targets genes. Furthermore, ectopic overexpression of SNHG3 increased the expression of c-Myc and its target genes, whereas inhibition of SNHG3 had opposite effect on the expression of c-Myc and its targets. Mechanistic investigations demonstrated that SNHG3 functioned as a competing endogenous RNA (ceRNA) to 'sponge' miR-182-5p, thus leading to the release of c-Myc from miR-182-5p and modulating the expression of c-Myc. In conclusion, SNHG3 promoted CRC progression via sponging miR-182-5p and upregulating c-Myc and its target genes.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-182"}
{"PMID":22348132,"Year":2012,"Title":"MiRNA genes constitute new targets for microsatellite instability in colorectal cancer.","Abstract":"Mismatch repair-deficient colorectal cancers (CRC) display widespread instability at DNA microsatellite sequences (MSI). Although MSI has been reported to commonly occur at coding repeats, leading to alterations in the function of a number of genes encoding cancer-related proteins, nothing is known about the putative impact of this process on non-coding microRNAs. In miRbase V15, we identified very few human microRNA genes with mono- or di-nucleotide repeats (n = 27). A mutational analysis of these sequences in a large series of MSI CRC cell lines and primary tumors underscored instability in 15 of the 24 microRNA genes successfully studied at variable frequencies ranging from 2.5% to 100%. Following a maximum likelihood statistical method, microRNA genes were separated into two groups that differed significantly in their mutation frequencies and in their tendency to represent mutations that may or may not be under selective pressures during MSI tumoral progression. The first group included 21 genes that displayed no or few mutations in CRC. The second group contained three genes, i.e., hsa-mir-1273c, hsa-mir-1303 and hsa-mir-567, with frequent (>/= 80%) and sometimes bi-allelic mutations in MSI tumors. For the only one expressed in colonic tissues, hsa-mir-1303, no direct link was found between the presence or not of mono- or bi-allelic alterations and the levels of mature miR expression in MSI cell lines, as determined by sequencing and quantitative PCR respectively. Overall, our results provide evidence that DNA repeats contained in human miRNA genes are relatively rare and preserved from mutations due to MSI in MMR-deficient cancer cells. Functional studies are now required to conclude whether mutated miRNAs, and especially the miR-1303, might have a role in MSI tumorigenesis.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-1303"}
{"PMID":28725241,"Year":2017,"Title":"miR-378 suppresses the proliferation, migration and invasion of colon cancer cells by inhibiting SDAD1.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) play important roles in the growth and metastasis of colon cancer. It is known that one set of miRNAs are dysregulated in colon cancer cells, but the mechanism of their role in cancer development is still largely unknown. Our study focuses on the role of miR-378 in colon cancer cells. METHODS: Human colon cancer tissues and adjacent non-tumor tissues were collected from patients diagnosed in pathological examinations. In addition, human colon cancer cell lines LoVo, CaCo2, SW1116, SW480 and HCT-116, and a normal colonic mucosa cell line NCM460 were included. Quantitative RT-PCR was used to detect the miR-378 level in the clinical tissues and cell lines. In SW480 and HCT-116, miR-378 was artificially overexpressed or suppressed. Cell viability and proliferation were measured using MTT and colony formation assays, and apoptosis was detected via annexin V-PI staining and flow cytometry analysis. The transwell technique was applied to detect the migration and invasion of the colon cancer cells, and their epithelial-mesenchymal transition (EMT) was evaluated by detecting EMT-associated markers using Western blotting. Bioinformatics methods were used to predict the potential targets of miR-378, and luciferase reporter assays were performed to conform the direct binding between miR-378 and its target mRNA. The activity of the Wnt/beta-catenin pathway was evaluated by detecting the key factors through Western blotting. RESULTS: We found that miR-378 expression was low in colon cancer tissues and cell lines. Overexpression of miR-378 not only inhibits the proliferation of colon cancer cells in vitro by inducing apoptosis, but also inhibits migration and invasion by inhibiting the EMT of colon cancer cells. SDAD1 is a direct target gene of miR-378, and knockdown of SDAD1 suppresses the proliferation, migration and invasion of colon cancer cells. We also confirmed that miR-378 alleviated the malignant phenotypes of colon cancer cells by inhibiting the Wnt/beta-catenin pathway. CONCLUSION: miR-378 inhibits the proliferation, migration and invasion of colon cancer cells by targeting SDAD1, defining miR-378 as a potential target for the diagnosis and treatment of colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-378"}
{"PMID":24145123,"Year":2014,"Title":"miR-203 induces oxaliplatin resistance in colorectal cancer cells by negatively regulating ATM kinase.","Abstract":"Chemotherapy for patients with metastatic colorectal cancer (CRC) is the standard of care, but ultimately nearly all patients develop drug resistance. Understanding the mechanisms that lead to resistance to individual chemotherapeutic agents may help identify novel targets and drugs that will, in turn, improve therapy. Oxaliplatin is a common component combination therapeutic regimen for use in patients with metastatic CRC, but is also used as a component of adjuvant therapy for patients at risk for recurrent disease. In this study, unbiased microRNA array screening revealed that the miR-203 microRNA is up-regulated in three of three oxaliplatin-resistant CRC cell lines, and therefore we investigated the role of miR-203 in chemoresistance. Exogenous expression of miR-203 in chemo-naive CRC cells induced oxaliplatin resistance. Knockdown of miR-203 sensitized chemoresistant CRC cells to oxaliplatin. In silico analysis identified ataxia telangiectasia mutated (ATM), a primary mediator of the DNA damage response, as a potential target of miR-203. ATM mRNA and protein levels were significantly down-regulated in CRC cells with acquired resistance to oxaliplatin. Using TCGA database, we identified a significant reverse correlation of miR-203 and ATM expression in CRC tissues. We validated ATM as a bona fide target of miR-203 in CRC cells. Mutation of the putative miR-203 binding site in the 3' untranslated region (3'UTR) of the ATM mRNA abolished the inhibitory effect of miR-203 on ATM. Furthermore, stable knockdown of ATM induced resistance to oxaliplatin in chemo-naive CRC cells. This is the first report of oxaliplatin resistance in CRC cells induced by miR-203-mediated suppression of ATM.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-203"}
{"PMID":30686821,"Year":2019,"Title":"Early modifications of circulating microRNAs levels in metastatic colorectal cancer patients treated with regorafenib.","Abstract":"Biomarkers able to improve the cost/benefit ratio are urgently needed for metastatic colorectal cancer patients that are eligible to receive regorafenib. Here, we measured plasma levels of ten circulating microRNAs (c-miRNAs) and we investigated their early changes during treatment, as well as possible correlation with clinical outcome. Ten literature-selected c-miRNAs were quantified by qRT-PCR on plasma samples collected at baseline (d1) and after 15 days of treatment (d15). C-miRNAs showing significant changes were further analyzed to establish correlations with outcome. A decision tree-based approach was employed to define a c-miRNA signature able to predict the outcome. Results achieved in an exploratory cohort were tested in a validation group. In the exploratory cohort (n = 34), the levels of c-miR-21 (p = 0.06), c-miR-141 (p = 0.04), and c-miR-601 (p = 0.01) increased at d15 compared with d1. A c-miRNA signature involving c-miR-21, c-miR-221, and c-miR-760 predicted response to treatment (p < 0.0001) and was significantly associated to PFS (HR = 10.68; 95% CI 3.2-35.65; p < 0.0001). In the validation cohort (n = 36), the increase in c-miR-21 (p = 0.02) and c-miR-601 (p = 0.02) levels at d15 was confirmed, but the associations with outcome were not. Our data indicate that early changes of c-miRNA levels might be influenced by regorafenib treatment. However, further studies are needed to establish the predictive power of such modifications.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-221"}
{"PMID":30166271,"Year":2018,"Title":"Serum-based microRNA signature predicts relapse and therapeutic outcome of adjuvant chemotherapy in colorectal cancer patients.","Abstract":"BACKGROUND: Approximately 60% of patients with colorectal cancer (CRC) undergo either local recurrence or distant metastases after surgery. Current prognostic biomarkers are insufficient to predict recurrence of CRC and provide little forecast information about what patients are likely to receive benefit from the adjuvant chemotherapy. As microRNAs (miRNAs) constantly exist in human serum and being used to predict the prognosis of a various cancers, this study was designed to identify miRNA-based circulating biomarkers to predict clinical outcomes of CRC. METHODS: A serum-focused miRNA expression was used to investigate if miRNA expression profiles could predict the clinical outcomes of patients with CRC. We created miRNA signature profiles associated in the training set (n =40), and further validated its prediction in two independent testing cohorts. RESULTS: Using Cox regression and risk-score analysis, we identified a four-miRNA signature (miR-652-3p, miR-342-3p, miR-501-3p and miR-328-3p) for the prediction of tumor relapse and the overall survival(OS) of patients with CRC in the training set (n=40). This miRNA signature was further validated in a testing set (n=226) and another independent cohort (n=56). A high-risk signature score was significantly associated with CRC tumor recurrence and poor treatment outcome. Multivariable Cox regression models indicated that the risk score, based on the four-miRNA signature, was an independent prognostic classifier for patients with CRC. CONCLUSIONS: The serum miRNA signature may serve as a minimally invasive predictor for tumor relapse and treatment outcome in patients with CRC and provide a useful reference for treatment selection.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-342"}
{"PMID":24705396,"Year":2014,"Title":"MiR-124 Radiosensitizes human colorectal cancer cells by targeting PRRX1.","Abstract":"One of the challenges in the treatment of colorectal cancer patients is that these tumors show resistance to radiation. MicroRNAs (miRNAs) are involved in essential biological activities, including chemoresistance and radioresistance. Several research studies have indicated that miRNA played an important role in sensitizing cellular response to ionizing radiation (IR). In this study, we found that miR-124 was significantly down-regulated both in CRC-derived cell lines and clinical CRC samples compared with adjacent non-tumor colorectal tissues, MiR-124 could sensitize human colorectal cancer cells to IR in vitro and in vivo. We identified PRRX1, a new EMT inducer and stemness regulator as a novel direct target of miR-124 by using target prediction algorithms and luciferase assay. PRRX1 knockdown could sensitize CRC cells to IR similar to the effects caused by miR-124. Overexpression of PRRX1 in stably overexpressed-miR-124 cell lines could rescue the effects of radiosensitivity enhancement brought by miR-124. Taking these observations into consideration, we illustrated that miR-124 could increase the radiosensitivity of CRC cells by blocking the expression of PRRX1, which indicated miR-124 could act as a great therapeutic target for CRC patients.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-124"}
{"PMID":27878288,"Year":2017,"Title":"MicroRNA-6826 and -6875 in plasma are valuable noninvasive biomarkers that predict the efficacy of vaccine treatment against metastatic colorectal cancer.","Abstract":"Various vaccine treatments against metastatic colorectal cancer have been developed and applied. However, to improve the efficacy of immunotherapy, biomarkers that can predict the effects are needed. It has been reported that various microRNAs (miRNAs) in peripheral blood may be useful as non-invasive biomarkers. In this study, miRNAs influencing the efficacy of vaccine treatment were screened for in a microarray analysis of 13 plasma samples that were obtained from patients prior to vaccine treatment. To validate the screening results, real-time RT-PCR was performed using 93 plasma samples obtained from patients prior to vaccine treatment. Four candidate miRNAs were selected according to the results of the comprehensive analysis of miRNA expression, which were ranked using the Fisher criterion and the absolute value of the log2 ratio in the screening analysis. The validation analysis showed that in the HLA-A*2402matched patient group (vaccine-treated group), patients with a high expression of plasma miR-6826 had a poorer prognosis than those with a low expression (P=0.048). In contrast, in the HLA-A*2402-unmatched patient group (control group), there was no difference between the patients with high or low plasma miR-6826 expression (P=0.168). Similar results were obtained in the analysis of miR-6875 (P=0.029 and P=0.754, respectively). Moreover, multivariate analysis of the Cox regression model indicated that the expression of miR-6826 was the most significant predictor for overall survival (P=0.003, hazard ratio, 3.670). In conclusion, plasma miR-6826 and miR-6875 may be predictive biomarkers for a poor response to vaccine treatment. Although further clarification is needed regarding the functions of miR-6826 and miR-6875 and their relationship to immunerelated molecules, plasma miR-6826 and miR-6875 may be useful negative biomarkers for predicting the efficacy of vaccine treatment.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-6875"}
{"PMID":28624481,"Year":2017,"Title":"miR-34a overexpression predicts poor prognostic outcome in colorectal adenocarcinoma, independently of clinicopathological factors with established prognostic value.","Abstract":"OBJECTIVES: MicroRNA-34a (miR-34a) is regulated by TP53 and, in response, downregulates the expression of a gamut of protein-coding genes, including apoptosis regulators, transcription factors, cyclins, and cyclin-dependent kinases. Its upregulation initiates a reprogramming of gene expression and promotes apoptosis. The purpose of this study was the investigation of the potential clinical significance of miR-34a as a molecular prognostic biomarker in colorectal adenocarcinoma using an in-house real-time quantitative PCR (qPCR) methodology. DESIGN AND METHODS: Total RNA was extracted from 113 primary colorectal adenocarcinoma specimens and 61 paired non-cancerous colorectal tissue samples. After polyadenylation and reverse transcription, miR-34a molecules were determined using qPCR based on SYBR Green chemistry. Calculations were performed using the comparative CT method. Finally, extensive biostatistical analysis was performed. RESULTS: miR-34a expression does not significantly differ between colorectal adenocarcinoma tissue specimens and adjacent non-cancerous mucosae. However, miR-34a expression increases progressively as colorectal adenocarcinoma loses its differentiation, being highest in grade III tumors (P=0.010). Moreover, miR-34a expression is a potential unfavorable prognostic biomarker in colorectal adenocarcinoma, predicting poor disease-free and overall survival (P=0.002 and P=0.019, respectively), independently of classical clinicopathological parameters. Most importantly, miR-34a expression stratifies patients without local (N0) and/or distant metastasis (M0) at the time of diagnosis into two groups with substantially different prognosis (P=0.013 and P=0.002, respectively). CONCLUSIONS: High miR-34a levels in colorectal adenocarcinoma predict a rather increased risk for disease recurrence and poor overall survival, particularly in patients at an early TNM stage. The unfavorable prognostic potential of miR-34a expression is independent of established prognostic features of colorectal adenocarcinoma.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":21406606,"Year":2011,"Title":"Integrated microRNA and mRNA expression profiling in a rat colon carcinogenesis model: effect of a chemo-protective diet.","Abstract":"We have recently demonstrated that nutritional bioactives (fish oil and pectin) modulate microRNA molecular switches in the colon. Since integrated analysis of microRNA and mRNA expression at an early stage of colon cancer development is lacking, in this study, four computational approaches were utilized to test the hypothesis that microRNAs and their posttranscriptionally regulated mRNA targets, i.e., both total mRNAs and actively translated mRNA transcripts, are differentially modulated by carcinogen and diet treatment. Sprague-Dawley rats were fed diets containing corn oil +/- fish oil with pectin +/- cellulose and injected with azoxymethane or saline (control). Colonic mucosa was assayed at an early time of cancer progression, and global gene set enrichment analysis was used to obtain those microRNAs significantly enriched by the change in expression of their putative target genes. In addition, cumulative distribution function plots and functional network analyses were used to evaluate the impact of diet and carcinogen combination on mRNA levels induced via microRNA alterations. Finally, linear discriminant analysis was used to identify the best single-, two-, and three-microRNA combinations for classifying dietary effects and colon tumor development. We demonstrate that polysomal profiling is tightly related to microRNA changes when compared with total mRNA profiling. In addition, diet and carcinogen exposure modulated a number of microRNAs (miR-16, miR-19b, miR-21, miR26b, miR27b, miR-93, and miR-203) linked to canonical oncogenic signaling pathways. Complementary gene expression analyses showed that oncogenic PTK2B, PDE4B, and TCF4 were suppressed by the chemoprotective diet at both the mRNA and protein levels.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-19"}
{"PMID":27498032,"Year":2016,"Title":"Let-7a inhibits tumor cell growth and metastasis by directly targeting RTKN in human colon cancer.","Abstract":"Colorectal cancer (CRC) is the third most common cancer worldwide, with high morbidity. MicroRNAs (miRNAs) are endogenous small RNAs that play important roles in regulating multiple biological and pathologic processes. The differential expression of miRNAs in CRC was first reported in 2003. Accumulated evidence indicates that lethal-7a (let-7a, miRNA) generally functions as a tumor suppressor in several human cancers. However, the role of let-7a in human colon cancer remains unclear. The aim of this study was to investigate the biological functions of let-7a and its potential role in colon cancer. We first discovered that let-7a level was significantly decreased in colon cancer tissues and cell lines (HT-29, HCT-116, LoVo, SW480, and SW620). To explore the effects of let-7a on colon cancer, let-7a over-expressed HCT-116 and SW620 cells were constructed. Further studies demonstrated that over-expressed let-7a could remarkably inhibit HCT-116 and SW620 cell growth and metastasis by directly down-regulating Rhotekin (RTKN). When RTKN was reintroduced into let-7a mimic transfected HCT-116 or SW620 cells, the inhibition effects of let-7a on colon cancer cell growth and metastasis were markedly reversed. In conclusion, our research shows that let-7a can inhibit tumor cell growth and metastasis by directly targeting RTKN in human colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"let-7"}
{"PMID":29588449,"Year":2018,"Title":"Confirmation of a metastasis-specific microRNA signature in primary colon cancer.","Abstract":"The identification of patients with high-risk stage II colon cancer who may benefit from adjuvant therapy may allow the clinical approach to be tailored for these patients based on an understanding of tumour biology. MicroRNAs have been proposed as markers of the prognosis or treatment response in colorectal cancer. Recently, a 2-microRNA signature (let-7i and miR-10b) was proposed to identify colorectal cancer patients at risk of developing distant metastasis. We assessed the prognostic value of this signature and additional candidate microRNAs in an independent, clinically well-defined, prospectively collected cohort of primary colon cancer patients including stage I-II colon cancer without and stage III colon cancer with adjuvant treatment. The 2-microRNA signature specifically predicted hepatic recurrence in the stage I-II group, but not the overall ability to develop distant metastasis. The addition of miR-30b to the 2-microRNA signature allowed the prediction of both distant metastasis and hepatic recurrence in patients with stage I-II colon cancer who did not receive adjuvant chemotherapy. Available gene expression data allowed us to associate miR-30b expression with axon guidance and let-7i expression with cell adhesion, migration, and motility.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-30"}
{"PMID":22983984,"Year":2012,"Title":"Downregulation of miR-144 is associated with colorectal cancer progression via activation of mTOR signaling pathway.","Abstract":"The mammalian target of rapamycin (mTOR) is a downstream integrator of essential pathways. mTOR signaling is frequently dysregulated in a variety of human cancers, and in silico analysis has revealed two miR-144 binding sites in the mTOR 3' untranslated region. We investigated the clinicopathologic magnitude of the mTOR pathway regulating microRNA, miR-144 in colorectal cancer (CRC) cases. The regulation of mTOR by miR-144 was examined with inhibitor miR-144-transfected cells. We also investigated changes in sensitivity to the mTOR inhibitor, rapamycin, in inhibitor miR-144-transfected cells. Quantitative RT-PCR was used to evaluate the clinicopathologic significance of miR-144 expression in 137 CRC. Furthermore, we assessed the correlation between CRC prognosis and the expression of 16 genes in the Akt/mTOR pathway. In vitro assays showed that mTOR is a direct target of miR-144, and downregulation of miR-144 facilitated proliferation of CRC cell line, HT29. In addition, the viability of HT29 cells with downregulated miR-144 expression was significantly reduced with rapamycin treatment. Low expression levels of miR-144 were associated with enhanced malignant potential such as venous invasion (P = 0.0013), liver metastasis (P = 0.08), liver recurrence (P = 0.0058) and poor prognosis (P = 0.0041). Multivariate analysis indicated that low miR-144 expression was an independent prognostic factor for survival. Among many genes consisting of the mTOR pathway, only high expression of Rictor was associated with poor prognosis of CRC. miR-144 is a meaningful prognostic marker. Downregulation of miR-144 leads to poor prognosis of CRC patients via activation of the mTOR signaling pathway.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-144"}
{"PMID":27013928,"Year":2016,"Title":"Time course analysis based on gene expression profile and identification of target molecules for colorectal cancer.","Abstract":"BACKGROUND: The study aimed to investigate the expression changes of genes in colorectal cancer (CRC) and screen the potential molecular targets. METHODS: The GSE37178 of mRNA expression profile including the CRC samples extracted by surgical resection and the paired normal samples was downloaded from Gene Expression Omnibus database. The genes whose expressions were changed at four different time points were screened and clustered using Mfuzz package. Then DAVID was used to perform the functional and pathway enrichment analysis for genes in different clusters. The protein-protein interaction (PPI) networks were constructed for genes in the clusters according to the STRING database. Furthermore, the related-transcription factors (TFs) and microRNAs (miRNAs) were obtained based on the resources in databases and then were combined with the PPI networks in each cluster to construct the integrated network containing genes, TFs and miRNAs. RESULTS: As a result, 314 genes were clustered into four groups. Genes in cluster 1 and cluster 2 showed a decreasing trend, while genes in cluster 3 and cluster 4 presented an increasing trend. Then 18 TFs (e.g., TCF4, MEF2C and FOS) and 18 miRNAs (e.g., miR-382, miR-217, miR-1184, miR-326 and miR-330-5p) were identified and three integrated networks for cluster 1, 3, and 4 were constructed. CONCLUSIONS: The results implied that expression of PITX2, VSNL1, TCF4, MEF2C and FOS are time-related and associated with CRC development, accompanied by several miRNAs including miR-382, miR-217, miR-21, miR-1184, miR-326 and miR-330-5p. All of them might be used as potential diagnostic or therapeutic target molecules for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-330"}
{"PMID":22641662,"Year":2012,"Title":"KRAS up-regulates the expression of miR-181a, miR-200c and miR-210 in a three-dimensional-specific manner in DLD-1 colorectal cancer cells.","Abstract":"BACKGROUND: We previously found that oncogenic KRAS induces increased expression of microRNAs (miRNAs), such as miR-200c and miR-221/222, in human colorectal cancer (CRC) HCT116 cells in a three-dimensional (3D)-specific manner, however, the regulation of miRNA expression through oncogenic KRAS in other types of CRC remains unclear. MATERIALS AND METHODS: The differential expression of 94 cancer-related miRNAs was examined in DLD-1 and DKO-4 cells (DLD-1 cells with a disrupted oncogenic KRAS) in 3D cultures. RESULTS: Increased miR-15b, miR-16, miR-23a, miR-24, miR-103 and miR-222 expression was observed in 3D and in 2D cultures. Of note, increased miR-181a, miR-200c and miR-210 expression was only observed in 3D cultures. Furthermore, miR-181a and miR-210 were significantly overexpressed in DLD-1 cells in 3D culture compared with those in HCT116 cells, and were significantly overexpressed in human CRC specimens. CONCLUSION: Oncogenic KRAS regulates 3D-specific miRNAs that are possibly associated with CRC development in vivo.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-103"}
{"PMID":27145368,"Year":2016,"Title":"Downregulation of miR-199b is associated with distant metastasis in colorectal cancer via activation of SIRT1 and inhibition of CREB/KISS1 signaling.","Abstract":"The progression of distant metastasis cascade is a multistep and complicated process, frequently leading to a poor prognosis in cancer patients. Recently, growing evidence has indicated that deregulation of microRNAs (miRNAs) contributes to tumorigenesis and tumor progression in colorectal cancer (CRC). In the present study, by comparing the miRNA expression profiles of CRC tissues and corresponding hepatic metastasis tissues, we established the downregulation of miR-199b in CRC metastasis tissues. The decrease in miR-199b expression was significantly correlated to late TNM stage and distant metastasis. Moreover, Kaplan-Meier curves showed that CRC patients with high expression level of miR-199b had a longer median survival. Functional assays results indicated that the restoration of miR-199b considerably reduced cell invasion and migration in vitro and in vivo, and increased the sensitivity to 5-FU and oxaliplatin. Further dual-luciferase reporter gene assays revealed that SIRT1 was the direct target of miR-199b in CRC. The expression of miR-199b was inversely correlated with SIRT1 in CRC specimens. SIRT1 knockdown produced effects on biological behavior that were similar to those of miR-199b overexpression. Furthermore, through Human Tumor Metastasis PCR Array we discovered KISS1 was one of the downstream targets of SIRT1. Silencing of SIRT1 upregulated KISS1 expression by enhancing the acetylation of the transcription factor CREB. The latter was further activated via binding to the promoter of KISS1 to induce transcription. Thus, we concluded that miR-199b regulates SIRT1/CREB/KISS1 signaling pathway and might serve as a prognosis marker or a novel therapeutic target for patients with CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-199"}
{"PMID":26744471,"Year":2016,"Title":"MicroRNA-155 deletion promotes tumorigenesis in the azoxymethane-dextran sulfate sodium model of colon cancer.","Abstract":"Clinical studies have linked microRNA-155 (miR-155) expression in the tumor microenvironment to poor prognosis. However, whether miR-155 upregulation is predictive of a pro- or antitumorigenic response is unclear, as the limited preclinical data available remain controversial. We examined miR-155 expression in tumor tissue from colon cancer patients. Furthermore, we investigated the role of this microRNA in proliferation and apoptosis, inflammatory processes, immune cell populations, and transforming growth factor-beta/SMAD signaling in a chemically induced (azoxymethane-dextran sulfate sodium) mouse model of colitis-associated colon cancer. We found a higher expression of miR-155 in the tumor region than in nontumor colon tissue of patients with colon cancer. Deletion of miR-155 in mice resulted in a greater number of polyps/adenomas, an increased symptom severity score, a higher grade of epithelial dysplasia, and a decrease in survival. Surprisingly, these findings were associated with an increase in apoptosis in the normal mucosa, but there was no change in proliferation. The protumorigenic effects of miR-155 deletion do not appear to be driven solely by dysregulation of inflammation, as both genotypes had relatively similar levels of inflammatory mediators. The enhanced tumorigenic response in miR-155(-/-) mice was associated with alterations in macrophages and neutrophils, as markers for these populations were decreased and increased, respectively. Furthermore, we demonstrated a greater activation of the transforming growth factor-beta/SMAD pathway in miR-155(-/-) mice, which was correlated with the increased tumorigenesis. Given the multiple targets of miR-155, careful evaluation of its role in tumorigenesis is necessary prior to any consideration of its potential as a biomarker and/or therapeutic target in colon cancer.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-155"}
{"PMID":24237355,"Year":2014,"Title":"miR-429 identified by dynamic transcriptome analysis is a new candidate biomarker for colorectal cancer prognosis.","Abstract":"Colorectal cancer (CRC) is a common malignant gastrointestinal cancer. Efforts for preventive and personalized medicine have intensified in the last decade with attention to novel forms of biomarkers. In the present study, microRNA and genetic analyses were performed in tandem for differential transcriptome profiling between primary tumors with or without nodes or distant metastases. Serial Test Cluster (STC) analysis demonstrated that 20 genes and two microRNAs showed distinctive expression patterns associated with the tumor, node, and metastasis (TNM) stage. The selected target genes were characterized by GO and Pathway analysis. A microRNA-target gene network analysis showed that miR-429 resided in the center of the network, indicating that miR-429 might serve important roles in the development of CRC. Real-time PCR and tissue microarrays showed that miR-429 had a dynamic expression pattern during the CRC progression stage, and was significantly downregulated in stage II and stage III clinical progression. The low expression of miR-429 was correlated with poor prognosis for CRC. Taken together, miR-429 warrant further clinical translation research as a candidate biomarker for CRC prognosis. Additional downstream targets and attendant gene function also need to be discerned to design a sound critical path to personalized medicine for persons susceptible to, or diagnosed with CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-429"}
{"PMID":24185900,"Year":2013,"Title":"SNAIL and miR-34a feed-forward regulation of ZNF281/ZBP99 promotes epithelial-mesenchymal transition.","Abstract":"Here, we show that expression of ZNF281/ZBP-99 is controlled by SNAIL and miR-34a/b/c in a coherent feed-forward loop: the epithelial-mesenchymal transition (EMT) inducing factor SNAIL directly induces ZNF281 transcription and represses miR-34a/b/c, thereby alleviating ZNF281 mRNA from direct down-regulation by miR-34. Furthermore, p53 activation resulted in a miR-34a-dependent repression of ZNF281. Ectopic ZNF281 expression in colorectal cancer (CRC) cells induced EMT by directly activating SNAIL, and was associated with increased migration/invasion and enhanced beta-catenin activity. Furthermore, ZNF281 induced the stemness markers LGR5 and CD133, and increased sphere formation. Conversely, experimental down-regulation of ZNF281 resulted in mesenchymal-epithelial transition (MET) and inhibition of migration/invasion, sphere formation and lung metastases in mice. Ectopic c-MYC induced ZNF281 protein expression in a SNAIL-dependent manner. Experimental inactivation of ZNF281 prevented EMT induced by c-MYC or SNAIL. In primary CRC samples, expression of ZNF281 increased during tumour progression and correlated with recurrence. Taken together, these results identify ZNF281 as a component of EMT-regulating networks, which contribute to metastasis formation in CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-34"}
{"PMID":30737378,"Year":2019,"Title":"The p300/YY1/miR-500a-5p/HDAC2 signalling axis regulates cell proliferation in human colorectal cancer.","Abstract":"The biological role of miR-500a-5p has not yet been reported in the context of colorectal cancer (CRC). Here, we show that miR-500a-5p expression is decreased in CRC tissues compared with adjacent normal tissues. Low miR-500a-5p expression is associated with malignant progression. Moreover, transfection of CRC cells with miR-500a-5p induces G0/G1 cell cycle arrest and inhibits their growth and migration. Mechanistically, miR-500a-5p directly targets HDAC2 and inhibits HDAC2-mediated proliferation in CRC in nude mice. Furthermore, YY1 binds to the promoter of miR-500a-5p and negatively regulates its transcription. Restoration of miR-500a-5p expression is up-regulated via the p300/YY1/HDAC2 complex. Besides, therapeutic delivery of miR-500a-5p significantly suppresses tumour development in a xenograft tumour model and a HDAC2 inhibitor FK228-treated CRC model. Our studies demonstrate that miR-500a-5p functions as a tumour suppressor in CRC by targeting the p300/YY1/HDAC2 axis, which contributes to the development of and provides new potential candidates for CRC therapy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-500"}
{"PMID":25757925,"Year":2015,"Title":"Induction of epithelial-mesenchymal transition and down-regulation of miR-200c and miR-141 in oxaliplatin-resistant colorectal cancer cells.","Abstract":"Epithelial-mesenchymal transition (EMT) and changes in the expression of the microRNA-200 (miR-200) family were examined in the human colorectal cancer (CRC) cell line SW620 with acquired oxaliplatin (L-OHP) resistance. Two CRC cell lines, SW480, derived from primary CRC, and SW620, derived from lymph node metastasis, which were obtained from the same patient, were used in the present study. L-OHP-resistant SW620 cells were obtained by exposure to L-OHP for 155 d. The concentration of L-OHP was increased to 80 microM in a stepwise manner. The IC50 value of L-OHP was increased 16-fold in L-OHP-resistant SW620 cells, which also displayed mesenchymal cell-like characteristics, such as the down-regulation of E-cadherin and up-regulation of vimentin. However, L-OHP-resistant SW480 cells were not obtained when the concentration of L-OHP was increased in a similar stepwise manner. The expression levels of members of the miR-200 family (miR-200a, miR-200b, miR-429, miR-200c, and miR-141) were significantly higher in SW480 cells than in SW620 cells. The expression levels of miR-200c and miR-141 were significantly lower in L-OHP-resistant SW620 cells than in control SW620 cells. L-OHP-resistant SW620 cells did not exhibit cross-resistance to other anti-cancer drugs used to treat CRC, such as 5-fluorouracil, irinotecan, and the active metabolite of irinotecan (SN-38). These results suggest that the down-regulated expression of miR-200c and miR-141 plays a role in selective resistance to L-OHP and EMT in CRC cells during repeated treatments with L-OHP.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-200"}
{"PMID":30883340,"Year":2019,"Title":"Expression levels of miR-143-3p and -424-5p in colorectal cancer and their clinical significance.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is one of the most prevalent cancers and microRNAs are involved in colorectal carcinogenesis and progression. The role of our candidate microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) have been investigated in various cancers. OBJECTIVE: The aim of the current study was to evaluate expression levels of microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) in the sera of patients with CRC in order to identify potential non-invasive biomarker for CRC and investigate the relationship between their expression and clinicopathological features of CRC. METHODS: The serological expression of candidate microRNAs were measured in 124 participants, including 62 CRC patients and 62 healthy controls and the serum expression levels of candidate miRNAs were quantified by stemloop reverse transcriptionquantitative polymerase chain reaction. RESULTS: In the present study, results showed a significant upregulation expression level of miR-424-5p (P< 0.001) and decreased expression level of miR143-3p was observed in the sera of patients with CRC (P< 0.001). Receiver operating characteristic (ROC) curve analysis demonstrated the area of miR-424-5p and miR-143-3p under the ROC curve for CRC diagnosis were 0.703 and 0.724 respectively (P< 0.001). In addition, down expression of miR-143-3p was significantly associated with tumor size (P= 0.005) and lymph node metastasis (P= 0.020) in CRC patients. CONCLUSIONS: The present investigation suggested that low expression of miR-143-3p and increasing level of miR-424-5p in CRC patients may play an important role in development of CRC and they could function as potential non-invasive biomarkers for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-424"}
{"PMID":28054337,"Year":2017,"Title":"Combined miRNA profiling and proteomics demonstrates that different miRNAs target a common set of proteins to promote colorectal cancer metastasis.","Abstract":"The process of liver colonization in colorectal cancer remains poorly characterized. Here, we addressed the role of microRNA (miRNA) dysregulation in metastasis. We first compared miRNA expression profiles between colorectal cancer cell lines with different metastatic properties and then identified target proteins of the dysregulated miRNAs to establish their functions and prognostic value. We found that 38 miRNAs were differentially expressed between highly metastatic (KM12SM/SW620) and poorly metastatic (KM12C/SW480) cancer cell lines. After initial validation, we determined that three miRNAs (miR-424-3p, -503, and -1292) were overexpressed in metastatic colorectal cancer cell lines and human samples. Stable transduction of non-metastatic cells with each of the three miRNAs promoted metastatic properties in culture and increased liver colonization in vivo. Moreover, miR-424-3p and miR-1292 were associated with poor prognosis in human patients. A quantitative proteomic analysis of colorectal cancer cells transfected with miR-424-3p, miR-503, or miR-1292 identified alterations in 149, 129, or 121 proteins, respectively, with an extensive overlap of the target proteins of the three miRNAs. Importantly, down-regulation of two of these shared target proteins, CKB and UBA2, increased cell adhesion and proliferation in colorectal cancer cells. The capacity of distinct miRNAs to regulate the same mRNAs boosts the capacity of miRNAs to regulate cancer metastasis and underscores the necessity of targeting multiple miRNAs for effective cancer therapy. Copyright (c) 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-424"}
{"PMID":26436952,"Year":2015,"Title":"MiR expression profiles of paired primary colorectal cancer and metastases by next-generation sequencing.","Abstract":"MicroRNAs (miRs) have been recognized as promising biomarkers. It is unknown to what extent tumor-derived miRs are differentially expressed between primary colorectal cancers (pCRCs) and metastatic lesions, and to what extent the expression profiles of tumor tissue differ from the surrounding normal tissue. Next-generation sequencing (NGS) of 220 fresh-frozen samples, including paired primary and metastatic tumor tissue and non-tumorous tissue from 38 patients, revealed expression of 2245 known unique mature miRs and 515 novel candidate miRs. Unsupervised clustering of miR expression profiles of pCRC tissue with paired metastases did not separate the two entities, whereas unsupervised clustering of miR expression profiles of pCRC with normal colorectal mucosa demonstrated complete separation of the tumor samples from their paired normal mucosa. Two hundred and twenty-two miRs differentiated both pCRC and metastases from normal tissue samples (false discovery rate (FDR) <0.05). The highest expressed tumor-specific miRs were miR-21 and miR-92a, both previously described to be involved in CRC with potential as circulating biomarker for early detection. Only eight miRs, 0.5% of the analysed miR transcriptome, were differentially expressed between pCRC and the corresponding metastases (FDR <0.1), consisting of five known miRs (miR-320b, miR-320d, miR-3117, miR-1246 and miR-663b) and three novel candidate miRs (chr 1-2552-5p, chr 8-20656-5p and chr 10-25333-3p). These results indicate that previously unrecognized candidate miRs expressed in advanced CRC were identified using NGS. In addition, miR expression profiles of pCRC and metastatic lesions are highly comparable and may be of similar predictive value for prognosis or response to treatment in patients with advanced CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-663"}
{"PMID":21826996,"Year":2011,"Title":"[Differential expression of colon cancer microRNA in microarry study].","Abstract":"OBJECTIVE: To investigate the miRNA expression difference between colon cancer and normal colonic mucosa. METHODS: Twelve (12) pairs of colorectal cancer tissue and normal colonic mucosa were collected, total RNA was extracted and purified. After fluorescent tags being added, hybridization was carried out on miRNA microarray chip (Affymetrix company). SAM analysis was performed to find out the significant expression difference, then the difference was verified by RT-PCR, finally target gene analysis software was utilized to predict the miRNA function. RESULTS: The up-regulated miRNAs in colon cancer included has-miR-182, has-miR-17, hasmiR-106a, has-miR-93, has-miR-200c, has-miR-92a, has-let-7a, has-miR-20a (FDR value < 5%), while the downregulated miRNAs were has-miR-l195, has-miR-143, has-miR-145 (FDR value < 5%). CONCLUSION: There is significant difference of miRNA expression between colon caner and normal colonic mucosa.","Language":"chi","Type":"Journal Article","Topic":"CRC","miRNA":"miR-143"}
{"PMID":28651018,"Year":2017,"Title":"Meta-analysis of miRNA expression profiles for prostate cancer recurrence following radical prostatectomy.","Abstract":"BACKGROUND: Prostate cancer (PCa) is a leading reason of death in men and the most diagnosed malignancies in the western countries at the present time. After radical prostatectomy (RP), nearly 30% of men develop clinical recurrence with high serum prostate-specific antigen levels. An important challenge in PCa research is to identify effective predictors of tumor recurrence. The molecular alterations in microRNAs are associated with PCa initiation and progression. Several miRNA microarray studies have been conducted in recurrence PCa, but the results vary among different studies. METHODS: We conducted a meta-analysis of 6 available miRNA expression datasets to identify a panel of co-deregulated miRNA genes and overlapping biological processes. The meta-analysis was performed using the 'MetaDE' package, based on combined P-value approaches (adaptive weight and Fisher's methods), in R version 3.3.1. RESULTS: Meta-analysis of six miRNA datasets revealed miR-125A, miR-199A-3P, miR-28-5P, miR-301B, miR-324-5P, miR-361-5P, miR-363*, miR-449A, miR-484, miR-498, miR-579, miR-637, miR-720, miR-874 and miR-98 are commonly upregulated miRNA genes, while miR-1, miR-133A, miR-133B, miR-137, miR-221, miR-340, miR-370, miR-449B, miR-489, miR-492, miR-496, miR-541, miR-572, miR-583, miR-606, miR-624, miR-636, miR-639, miR-661, miR-760, miR-890, and miR-939 are commonly downregulated miRNA genes in recurrent PCa samples in comparison to non-recurrent PCa samples. The network-based analysis showed that some of these miRNAs have an established prognostic significance in other cancers and can be actively involved in tumor growth. Gene ontology enrichment revealed many target genes of co-deregulated miRNAs are involved in \"regulation of epithelial cell proliferation\" and \"tissue morphogenesis\". Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that these miRNAs regulate cancer pathways. The PPI hub proteins analysis identified CTNNB1 as the most highly ranked hub protein. Besides, common pathway analysis showed that TCF3, MAX, MYC, CYP26A1, and SREBF1 significantly interact with those DE miRNA genes. The identified genes have been known as tumor suppressors and biomarkers which are closely related to several cancer types, such as colorectal cancer, breast cancer, PCa, gastric, and hepatocellular carcinomas. Additionally, it was shown that the combination of DE miRNAs can assist in the more specific detection of the PCa and prediction of biochemical recurrence (BCR). CONCLUSION: We found that the identified miRNAs through meta-analysis are candidate predictive markers for recurrent PCa after radical prostatectomy.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-363"}
{"PMID":24568449,"Year":2014,"Title":"Associations of single nucleotide polymorphisms in miR-146a, miR-196a, miR-149 and miR-499 with colorectal cancer susceptibility.","Abstract":"BACKGROUND: MicroRNAs (miRNAs) are an abundant class of endogenous small non-coding RNAs of 20-25 nucleotides in length that function as negative gene regulators. MiRNAs play roles in most biological processes, as well as diverse human diseases including cancer. Recently, many studies investigated the association between SNPs in miR-146a rs2910164, miR-196a2 rs11614913, miR-149 rs229283, miR-499 rs3746444 and colorectal cancer (CRC), which results have been inconclusive. METHODOLOGY/PRINCIPAL FINDINGS: PubMed, EMBASE, CNKI databases were searched with the last search updated on November 5, 2013. For miR-196a2 rs11614913, a significantly decreased risk of CRC development was observed under three genetic models (dominant model: OR = 0.848, 95%CI: 0.735-0.979, P = 0.025; recessive model: OR = 0.838, 95%CI: 0.721-0.974, P = 0.021; homozygous model: OR = 0.754, 95%CI: 0.627-0.907, P = 0.003). In the subgroup analyses, miR-196a2*T variant was associated with a significantly decreased susceptibility of CRC (allele model: OR = 0.839, 95%CI: 0.749-0.940, P = 0.000; dominant model: OR = 0.770, 95%CI: 0.653-0.980, P = 0.002; recessive model: OR = 0.802, 95%CI: 0.685-0.939, P = 0.006; homozygous model: OR = 0.695, 95%CI: 0.570-0.847, P = 0.000). As for miR-149 rs2292832, the two genetic models (recessive model: OR = 1.199, 95% CI 1.028-1.398, P = 0.021; heterozygous model: OR = 1.226, 95% CI 1.039-1.447, P = 0.013) demonstrated increased susceptibility to CRC. On subgroup analysis, significantly increased susceptibility of CRC was found in the genetic models (recessive model: OR = 1.180, 95% CI 1.008-1.382, P = 0.040; heterozygous model: OR = 1.202, 95% CI 1.013-1.425, P = 0.013) in the Asian group. CONCLUSIONS: These findings supported that the miR-196a2 rs11614913 and miR-149 rs2292832 polymorphisms may contribute to susceptibility to CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-149"}
{"PMID":31221189,"Year":2019,"Title":"EV-associated miRNAs from peritoneal lavage as potential diagnostic biomarkers in colorectal cancer.","Abstract":"BACKGROUND: Colorectal cancer (CRC) is the third leading cause of cancer-related mortality worldwide. Current systematic methods for diagnosing have inherent limitations so development of a minimally-invasive diagnosis, based on the identification of sensitive biomarkers in liquid biopsies could therefore facilitate screening among population at risk. METHODS: In this study, we aim to develop a novel approach to identify highly sensitive and specific biomarkers by investigating the use of extracellular vesicles (EVs) isolated from the peritoneal lavage as a source of potential miRNA diagnostic biomarkers. We isolated EVs by ultracentrifugation from 25 ascitic fluids and 25 peritoneal lavages from non-cancer and CRC patients, respectively. Analysis of the expression of EV-associated miRNAs was performed using Taqman OpenArray technology through which we could detect 371 miRNAs. RESULTS: 210 miRNAs were significantly dysregulated (adjusted p value < 0.05 and abs(logFC) >/= 1). The top-10 miRNAs, which had the AUC value higher than 0.95, were miRNA-199b-5p, miRNA-150-5p, miRNA-29c-5p, miRNA-218-5p, miRNA-99a-3p, miRNA-383-5p, miRNA-199a-3p, miRNA-193a-5p, miRNA-10b-5p and miRNA-181c-5p. CONCLUSIONS: This finding opens the avenue to the use of EV-associated miRNA of peritoneal lavages as an untapped source of biomarkers for CRC.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-29"}
{"PMID":25720255,"Year":2014,"Title":"[Coordinated aberranit expression of miRNAs in colon cancer].","Abstract":"Applying the method of multiple parallel sequencing on the MiSeq platform (Illumina, United States), a comparative analysis of miRNA expression in tumor and normal colon tissuie cells was performed. Forty miRNAs aberrantly expressed in cancer were detected. Among them, 15 and 25 miRNAs showed increased arid decreased expression, respectively, for all or most of the cases. Sixteen miRNA clusters were identified, which showed a coordinated or incompletely coordinated aberrant expression in colorectal cancer cells. In two (miR-183/182 and miR-106b/25) and four (miR-143/145, miR-497/195, miR-30e/30c-1, and miR-30a/30c-2) miRNA clusters, respectively, a statistically significant coordinated increase or decrease in expression was iegistered for all miRNAs withini the corresponding cluster. Three aberrantly expressed well-known miRNAs (miR-100-5p, mil-30d-5p, and miR-204-5p) were identified, which, however, had never 'before been associated with coloreictal cancer. The obtained results demonstrate the potential and promising application of 6 miRNA clusters with' coordinated aberrant expression as markers for colorectal cancer.","Language":"rus","Type":"Journal Article","Topic":"CRC","miRNA":"miR-106"}
{"PMID":24239208,"Year":2013,"Title":"Prognostic and predictive value of a microRNA signature in stage II colon cancer: a microRNA expression analysis.","Abstract":"BACKGROUND: Current staging methods do not accurately predict the risk of disease recurrence and benefit of adjuvant chemotherapy for patients who have had surgery for stage II colon cancer. We postulated that expression patterns of multiple microRNAs (miRNAs) could, if combined into a single model, improve postoperative risk stratification and prediction of chemotherapy benefit for these patients. METHOD: Using miRNA microarrays, we analysed 40 paired stage II colon cancer tumours and adjacent normal mucosa tissues, and identified 35 miRNAs that were differentially expressed between tumours and normal tissue. Using paraffin-embedded specimens from a further 138 patients with stage II colon cancer, we confirmed differential expression of these miRNAs using qRT-PCR. We then built a six-miRNA-based classifier using the LASSO Cox regression model, based on the association between the expression of every miRNA and the duration of individual patients' disease-free survival. We validated the prognostic and predictive accuracy of this classifier in both the internal testing group of 138 patients, and an external independent group of 460 patients. FINDINGS: Using the LASSO model, we built a classifier based on the six miRNAs: miR-21-5p, miR-20a-5p, miR-103a-3p, miR-106b-5p, miR-143-5p, and miR-215. Using this tool, we were able to classify patients between those at high risk of disease progression (high-risk group), and those at low risk of disease progression (low-risk group). Disease-free survival was significantly different between these groups in every set of patients. In the initial training group of patients, 5-year disease-free survival was 89% (95% CI 77.3-94.4) for the low-risk group, and 60% (46.3-71.0) for the high-risk group (hazard ratio [HR] 4.24, 95% CI 2.13-8.47; p<0.0001). In the internal testing set of patients, 5-year disease-free survival was 85% (95% CI 74.3-91.8) for the low-risk group, and 57% (42.8-68.5) for the high-risk group (HR 3.63, 1.86-7.01; p<0.0001), and in the independent validation set of patients, was 85% (79.6-89.0) for the low-risk group and 54% (46.4-61.1) for the high-risk group (HR 3.70, 2.56-5.35; p<0.0001). The six-miRNA-based classifier was an independent prognostic factor for, and had better prognostic value than, clinicopathological risk factors and mismatch repair status. In an ad-hoc analysis, the patients in the high-risk group were found to have a favourable response to adjuvant chemotherapy (HR 1.69, 1.17-2.45; p=0.0054). We developed two nomograms for clinical use that integrated the six-miRNA-based classifier and four clinicopathological risk factors to predict which patients might benefit from adjuvant chemotherapy after surgery for stage II colon cancer. CONCLUSION: Our six-miRNA-based classifier is a reliable prognostic and predictive tool for disease recurrence in patients with stage II colon cancer, and might be able to predict which patients benefit from adjuvant chemotherapy. It might facilitate patient counselling and individualise management of patients with this disease. FUNDING: Natural Science Foundation of China.","Language":"eng","Type":"Journal Article","Topic":"CRC","miRNA":"miR-143"}