Diagnostic and prognostic value of miR-106a in colorectal cancer

Dysregulated microRNAs participate in the crosstalk between colorectal cancer and atrial fibrillation

Colorectal cancer and atrial fibrillation share several common risk factors, and the incidence of the two diseases also exhibits a certain correlation. The above facts suggest a potential interaction mechanism between them, which has obtained increasing attention in the scientific community but remains to be further explored. Participating in diverse physiological and pathological processes, miRNAs exert important roles in both occurrence and growth of colorectal cancer and atrial fibrillation. To fill the gap in the understanding of the potential linkage between two diseases, the present study collected dysregulated miRNAs of colorectal cancer and atrial fibrillation from previous studies and then selected the miRNAs with the same change trends in both diseases. Finally, we reviewed the potential crosstalk of two diseases focusing on the roles of 6 dysregulated miRNAs, including 3 co-downregulated miRNAs (hsa-mir-126, hsa-mir-133a and hsa-mir-150) and 3 co-upregulated miRNAs (hsa-mir-106a, hsa-mir-155 and hsa-mir-21). The molecular mechanisms mediated by these miRNAs in colorectal cancer and atrial fibrillation were reviewed, and the possible crosstalk between the two diseases was discussed from the perspective of miRNAs. This study also provides potential common targets for preventive and curative measures against both colorectal cancer and atrial fibrillation.

Experimental validation of in silico analysis estimated the reverse effect of upregulated hsa‐miR ‐106a‐5p and hsa‐miR ‐223‐3p on SLC4A4 gene expression in Iranian patients with colorectal adenocarcinoma by RT‐qPCR

BACKGROUND AND METHODS

Colorectal cancer (CRC) is considered one of the most common malignancies worldwide. The diagnosis and prognosis of the patients are very poor. In this study, we used in-silico analysis and experimental techniques to investigate novel co-expression genes and their associated miRNA networks in CRC. For this purpose, we conducted a comprehensive transcriptome analysis using online bulk and single-cell RNA-seq datasets. We then validated the results on tissue samples from cancerous and adjacent normal tissues from CRC patients by RT-qPCR.

RESULTS

Using a weighted gene co-expression network algorithm, we identified SLC4A4 as a significantly downregulated hub gene in the CRC. The single-cell analysis indicated that the expression level of SLC4A4 in Paneth cells is higher than in other cell populations. Further computational analysis suggested hsa-miR-223-3p and hsa-miR-106a-5p as two specific hub-miRNAs for the SLC4A4 gene. RT-qPCR analysis showed a 2.60-fold downregulation of SLC4A4. Moreover, hsa-miR-223-3p and hsa-miR-106a-5p showed an increased expression level of 5.58-fold and 9.66-fold in CRC samples, respectively. Based on the marginal model analysis, by increasing the expression of hsa-miR-106a-5p, the average expression of the SLC4A4 gene significantly decreased by 103 units. Furthermore, ROC curves analysis indicated statistically significant for diagnostic ability of SLC4A4 (AUC: 0.94, Sensitivity: 95.5%, Specificity: 95.5%) and hsa-miR-106a-5p (AUC: 0.72, Sensitivity: 72.7%, Specificity: 100%).

CONCLUSION

This study provides a framework of co-expression gene modules and miRNAs of CRC, which identifies some important biomarkers for CRC pathogenicity and diagnosis. Further experimental evidence will be required to support this study and validate the precise molecular pathways.

OncomiRs miR-106a and miR-17 negatively regulate the nucleoside-derived drug transporter hCNT1

High-affinity uptake of natural nucleosides as well as nucleoside derivatives used in anticancer therapies is mediated by human concentrative nucleoside transporters (hCNTs). hCNT1, the hCNT family member that specifically transports pyrimidines, is also a transceptor involved in tumor progression. In particular, oncogenesis appears to be associated with hCNT1 downregulation in some cancers, although the underlying mechanisms are largely unknown. Here, we sought to address changes in colorectal and pancreatic ductal adenocarcinoma-both of which are important digestive cancers-in the context of treatment with fluoropyrimidine derivatives. An analysis of cancer samples and matching non-tumoral adjacent tissues revealed downregulation of hCNT1 protein in both types of tumor. Further exploration of the putative regulation of hCNT1 by microRNAs (miRNAs), which are highly deregulated in these cancers, revealed a direct relationship between the oncomiRs miR-106a and miR-17 and the loss of hCNT1. Collectively, our findings provide the first demonstration that hCNT1 inhibition by these oncomiRs could contribute to chemoresistance to fluoropyrimidine-based treatments in colorectal and pancreatic cancer.

Biomarker roles identification of miR-106 family for predicting the risk and poor survival of colorectal cancer

Background

Recent studies have extensively investigated the roles of miR-106 in colorectal cancer (CRC). However, the associations and molecular mechanism underlying the roles of miR-106 in CRC remain unclear. We aimed to thoroughly investigate the biomarker roles of miR-106 for predicting the risk and survival outcome in CRC.

Methods

We first conducted a comprehensive meta-analysis to quantitatively evaluate the roles of miR-106 in the diagnosis and prognosis of CRC. Then, we qualitatively explored the biomarker roles of miR-106 in CRC through an integrative bioinformatics analysis.

Results

The results indicated that miR-106 yielded a combined AUC of 0.79 (95% CI: 0.76–0.83), with a pooled sensitivity of 0.50 (95% CI: 0.32–0.68) and a pooled specificity of 0.93 (95% CI: 0.79–0.98) for discriminating CRC cases from normal controls. Moreover, patients with higher expression of miR-106 were significantly associated with shorter disease-free survival (HR: 1.73; 95%CI: 1.23–2.44) and overall survival (HR: 1.39; 95%CI: 1.09–1.77). Finally, gene ontology and pathway analysis demonstrated that miR-106 family was highly involved in the initiation and progression of CRC and indicated the potential molecular mechanism for miR-106 in CRC.

Conclusions

Our results indicated that miR-106 showed promising potential as diagnostic and prognostic biomarker for CRC. Nevertheless, the underlying molecular mechanism of miR-106 family involved in CRC requires further investigation.

Long non-coding RNA HOTAIR modulates the progression of preeclampsia through inhibiting miR-106 in an EZH2-dependent manner

AIMS

Preeclampsia (PE) accounts for the foremost cause of maternal and fetal mortality worldwide, whereas, there are no effective treatments for the disease yet. Long non-coding RNAs (lncRNAs) play critical roles in various human disorders, including PE. Here, we identified an up-regulated lncRNA HOTAIR, and explored its underlying mechanisms in PE.

MAIN METHODS

qRT-PCR analysis was used to examine HOTAIR expression in PE tissues and cell lines. Trophoblast proliferation was examined by colony formation and 5-Ethynyl-2'-deoxyuridine (EdU) incorporation assays. Trophoblast migration and invasion was determined by transwell and wound healing assays. Bioinformatics analysis was performed to verify the regulation HOTAIR on miRNAs. The interaction between HOTAIR and EZH2 was detected using RNA immunoprecipitation assay (RIP). Chromatin immunoprecipitation (CHIP) assay was also performed to verify that the negative regulation of HOTAIR on miR-106a was dependent on the epigenetic repressor EZH2.

KEY FINDINGS

HOTAIR was up-regulated in PE placenta tissues, which repressed the proliferation, migration and invasion of trophoblast cells. HOTAIR significantly repressed miR-106a expression and the reduced miR-106a level was also observed in placentas from PE patients. Additionally, miR-106a mimic enhanced the migration and invasion of trophoblast cells. Further mechanistic analyses implied that the action of HOTAIR is moderately attributable to its repression of miR-106a via association with EZH2.

SIGNIFICANCE

High level of HOTAIR repressed the proliferation, migration and invasion of trophoblast cells through targeting miR-106 in an EZH2-dependent manner, which may provide new insights into the roles of HOTAIR and miR-106a as potential regulators in PE.

Epigenetics of colorectal cancer: biomarker and therapeutic potential

Colorectal cancer (CRC), a leading cause of cancer-related death worldwide, evolves as a result of the stepwise accumulation of a series of genetic and epigenetic alterations in the normal colonic epithelium, leading to the development of colorectal adenomas and invasive adenocarcinomas. Although genetic alterations have a major role in a subset of CRCs, the pathophysiological contribution of epigenetic aberrations in this malignancy has attracted considerable attention. Data from the past couple of decades has unequivocally illustrated that epigenetic marks are important molecular hallmarks of cancer, as they occur very early in disease pathogenesis, involve virtually all key cancer-associated pathways and, most importantly, can be exploited as clinically relevant disease biomarkers for diagnosis, prognostication and prediction of treatment response. In this Review, we summarize the current knowledge on the best-studied epigenetic modifications in CRC, including DNA methylation and histone modifications, as well as the role of non-coding RNAs as epigenetic regulators. We focus on the emerging potential for the bench-to-bedside translation of some of these epigenetic alterations into clinical practice and discuss the burgeoning evidence supporting the potential of emerging epigenetic therapies in CRC as we usher in the era of precision medicine.

Overexpression of miR-106a enhances oxaliplatin sensitivity of colorectal cancer through regulation of FOXQ1

Chemotherapy resistance poses a major challenge for the clinical treatment of colorectal cancer, therefore, the aim of the present study was to examine its underlying mechanisms. Reverse transcription-quantitative polymerase chain reaction and western blot analysis were used to determine the microRNA (miRNA)/mRNA and protein expression levels, respectively. A dual luciferase assay was conducted for verification of the interaction between miR-106a and 3′untranslated region (UTR) of Forkhead box Q1 (FOXQ1). Cell viability was assessed using an MTT assay. In the present study, it was demonstrated that miR-106a is involved in regulating oxaliplatin sensitivity of colorectal cancer. Transfection of miR-106a mimics slightly inhibited colorectal cancer cell growth and sensitized colorectal cancer cells to oxaliplatin exposure. In addition, miR-106a overexpression induced a decrease of FOXQ1 at mRNA and protein levels in colorectal cancer cells. The enhanced expression of miR-106a also increased the expression of Wnt target genes, including vascular endothelial growth factor-A and matrix metallopeptidase 2, which were reported to be regulated by FOXQ1. It was predicted and validated that miR-106a could repress FOXQ1 expression via direct binding to 3′UTR. Elevation of miR-106a and a decrease of FOXQ1 expression levels were detected in tumor tissues from patients with oxaliplatin-sensitive colorectal cancer, compared with patients with oxaliplatin-resistant colorectal cancer. Furthermore, there was a significant association between miR-106a and FOXQ1 mRNA levels. In conclusion, the present study demonstrated that miR-106a increased oxaliplatin sensitivity of colorectal cancer cells through direct repression of FOXQ1 expression.

Association between LINC00657 and miR-106a serum expression levels and susceptibility to colorectal cancer, adenomatous polyposis, and ulcerative colitis in Egyptian population

Colorectal cancer (CRC) represented the second cause of mortality among cancer patients. Long noncoding RNAs and microRNAs (miRNAs) serve as noninvasive biomarkers for CRC surveillance and introduce new therapeutic approaches. LINC00657 and miR-106a expression levels play a pivotal role in CRC. This study included 190 Egyptian subjects, and the expression levels of LINC00657 and miR-106a in serum were measured by using quantitative real-time polymerase chain reaction. We found that upregulation of LINC00657 and downregulation of miR-106a are significantly associated with the development of CRC. Also, a positive correlation was detected between their serum levels. In addition, serum LINC00657 can distinguish adenomatous polyposis (AP) patients and/or ulcerative colitis (UC) patients from controls. Also the miRNA-106a expression level discriminates AP but not UC from healthy individuals. Our study cited new diagnostic biomarkers for CRC, AP, and UC among Egyptians in addition to be noninvasive screening tools for CRC in both healthy subjects and those having precancerous lesions. © 2019 IUBMB Life, 71(9):1322-1335, 2019.

Long Noncoding RNAs in Colorectal Adenocarcinoma; an in silico Analysis

Long noncoding RNAs (lncRNAs) are lengthy noncoding transcripts which are involved in critical signaling pathways including cell cycle and apoptosis so it is not surprising to see their altered expression in human tumors. Colorectal adenocarcinoma is one the most frequent malignancies worldwide. The role of lncRNAs in colorectal adenocarcinoma is not well understood. To study the significance of lncRNAs in colorectal adenocarcinoma, we retrieved 189 approved lncRNAs from HGNC. The genes were imported into the cBioPortal database for transcriptomic analyses. We queried all the samples from TCGA provisional colorectal adenocarcinoma with RNA-seq v2 data in our study and considered RNA dysregulation with Z-score: ±2. The lncRNA which was altered in most of the patients were considered as "significant lncRNA" for further analyses. We considered the association of candidate lncRNAs with clinicopathologic parameters of samples including tumor disease anatomic site, neoplasm histologic types, tumor stage and survival. We also compute the specificity of the significant lncRNAs expression in colorectal adenocarcinoma comparing with other human cancers in cancer portal. Our analysis showed that lncRNAs SNHG6, PVT1 and ZFAS1 allocated the maximum alteration among the colorectal cases. The expression of SNHG6 and ZFAS1 was more in rectal adenocarcinoma than the colon carcinoma while the PVT1 showed the same expression levels in both tissues. However, we found that upregulation of PVT1 has been reduced the overall survival in patients. Altogether these data showed SNHG6, PVT1 and ZFAS1, are promising candidates for experimental research on colorectal adenocarcinoma to discover novel biomarker for this prevalent cancer.

Prognostic value of microRNAs in colorectal cancer: a meta-analysis

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.

Clinical significance of miRNA - 106a in non-small cell lung cancer patients who received cisplatin combined with gemcitabine chemotherapy

Objective:

Research has demonstrated that microRNA (miR)-106a is related to cisplatin resistance. We investigated the expression of miR-106a in the serum of patients with non-small cell lung cancer (NSCLC) and their sensitivity to chemotherapy by cisplatin combined with gemcitabine.

Methods:

Eighty-five NSCLC patients, who completed four cycles of gemcitabine and cisplatin chemotherapy, volunteered for this study and their serum samples were collected. Serum samples from 60 healthy subjects were used as controls. Real-time quantitative polymerase chain reaction (real-time qPCR) was used to quantify the level of miR-106a in the serum. Demographic and survival data of these patients were collected for the analysis.

Results:

The expression of miR-106a in the serum of NSCLC patients was significantly higher than that of healthy subjects (P < 0.001). The expression of miR-106a was not correlated with patients' gender, age, tumor size, lymphatic metastasis, and pathological types; but was correlated with patients' tumor staging ( P = 0.003). After chemotherapy, serum miR-106a expression decreased in patients. The decrease in miR-106a expression in the chemotherapy-sensitive group was much higher than that in the chemotherapy-resistant group. Survival analysis shows that NSCLC patients with high expression of miR-106a have a poorer prognosis. The overall survival of NSCLC patients in the chemotherapy-sensitive group was significantly higher than that in the chemotherapy-resistant group.

Conclusions:

High expression of miR-106a may be involved in the development of NSCLC. MiR-106a has significance in the prognosis of NSCLC. The level of miR-106a in the serum can be a useful parameter in screening for drug resistance during cisplatin-based chemotherapy.

lncRNAs as prognostic molecular biomarkers in hepatocellular carcinoma: a systematic review and meta-analysis

The latest studies have shown that long non-coding RNAs (lncRNAs) may be considered markers as their expression levels were abnormal in cancer and can be used as a molecular biomarker for the potential assessment of cancer prognosis. In this study, we aimed to assess the prognostic value of lncRNA as marker of patients with hepatocellular carcinoma. We performed a detailed search of the PubMed and Embase databases for articles on the prognostic value of various lncRNAs in HCC. We then carefully extracted the relevant data from the articles, and we used the meta-analysis method to analyze these results; heterogeneity and publication bias were also evaluated. With 40 associative studies included, we found that high expression of 27 types of lncRNA was associated with a poor prognosis in HCC patients, and low expression of 18 types of lncRNAs was associated with a worse prognosis. Patients with higher lncRNA expression had significantly poor overall survival (OS; pooled HR, 1.25; 95% confidence interval [CI], 1.03–1.52) as well as significantly poor recurrence-free survival (RFS; pooled HR, 1.66; 95% CI, 1.26–2.17). Overexpression of lncRNAs may not meaningfully predict disease-free survival (DFS; pooled HR, 1.04; 95% CI, 0.52–2.07; p = 0.91). Our meta-analysis demonstrated that lncRNAs may serve as predictive biomarkers for cancer prognosis.

miR-203 as a novel biomarker for the diagnosis and prognosis of colorectal cancer: a systematic review and meta-analysis

We sought to systematically evaluate the diagnostic and prognostic value of miR-203 in patients with colorectal cancer. To explore the diagnostic performance of miR-203, eligible studies were identified from biomedical databases. Based on these results, 11 studies were pooled and included in this meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratios of miR-203 were 0.83 (95% confidence interval, CI: 0.78–0.86), 0.80 (95% CI: 0.77–0.83), and 19.27 (95% CI: 7.23–51.36) for the diagnosis of colorectal cancer. The area under the curve for miR-203 for diagnosing colorectal cancer was 0.89. Patients with higher expression of tissue miR-203 had poor overall survival (pooled hazard ratio: 1.63; 95% CI: 1.03–2.57, P=0.04), but serum miR-203 was not predictive (pooled hazard ratio: 1.59; 95% CI: 0.31–8.12, P=0.58). The miR-203 values of tissue and serum merged together may perhaps predict superior overall survival (pooled hazard ratio: 1.62; 95% CI: 0.93–2.82), but the effect was not significant (P=0.09).

miR-106a suppresses tumor cells death in colorectal cancer through targeting ATG7

Autophagy-related gene 7 (ATG7) and miR-106a play an important role in cancer cell autophagy and apoptosis, but the outcome of ATG7 and miR-106a in colorectal cancer (CRC) still remains not clear. In this study, we found that ATG7 and miR-106a expression were mutually related with cell death and prognosis in CRC patients. In addition, we also showed that ATG7 and miR-106a expression were changeable in colorectal cancer cell lines when compared with normal cell lines, but ATG7 and miR-106a mRNA level was negatively correlated. Furthermore, ATG7 protein and mRNA levels decreased after over-expression of miR-106a, whereas the suppression of ATG7 had the opposite effect. We confirmed that miR-106a down-regulated ATG7 mRNA level by binding the specific sequence of ATG7 mRNA 3'UTR region. Moreover, the over-expression of ATG7 induced CRC cells death both in vitro and in vivo. Taken together, our study data demonstrated that ATG7 aggravated the cell death of CRC, which was inhibited by miR-106a.