Expression profiling of miR-96, miR-584 and miR-422a in colon cancer and their potential involvement in colon cancer pathogenesis

Min Lu,Feng-Jun Liu,Xuan Zhou,Cheng-Guo Zheng

doi:10.4314/tjpr.v15i12.1

Abstract

Purpose: To determine the correlation between miRNAs; miR-96, miR-422a and miR584, and colon cancer, and also to test whether any of these miRNAs can act as non-invasive biomarkers in colon cancerMethods: The tumor samples and the corresponding normal mucosa used in this study were collected from 60 patients diagnosed with colon cancer. HT-29, HCT-116 and SW-620 cell lines were used for miRNA expression profiling. Total RNA was extracted using kit-based methods with minor modifications, and specific miRNAs were detected and quantified by quantitative real-time polymerase chain reaction [RT-PCR].Results: The results indicate down-regulation of miR-96, miR-584 and miR-422a in colon cancer tissue and decreased expression levels in the three colon cancer cell lines (all p < 0.01). Lower miRNA expression levels are correlated with increased tumor size.Conclusion: This study shows that miR-96, miR-584 and miR-422a are down-regulated in colon cancer and are associated with tumor size. Thus, the ratio of miR-96/miR-638 in plasma is a potential noninvasive biomarker in colon cancer.Keywords: Colon cancer, miR-96, miR-422a, miR-584, Expression profiling, Biomarker

Highlights

MicroRNAs are relatively newly discovered class of molecules that play crucial roles in cellular processes in humans and other mammals. miRNAs are transcribed by RNA polymerase II and do not code for any proteins, and are of varying lengths ranging between 20 and 25 nucleotides [1]
The results indicated significantly lower expression levels of miR-96, miR-584 and miR-422a in all the three colon cancer cell lines compared to the randomized normal mucosal tissue from patients (Fig 2d)
We evaluated the association between miR-96, miR-584 and miR-422a expression levels and clinicopathological characteristics in colon cancer patients

Summary

INTRODUCTION

MicroRNAs (miRNAs) are relatively newly discovered class of molecules that play crucial roles in cellular processes in humans and other mammals. miRNAs are transcribed by RNA polymerase II and do not code for any proteins, and are of varying lengths ranging between 20 and 25 nucleotides [1]. Since the afore-stated procedures are based on the late onset of colon cancer, it is important to develop early stage detection methods that have the potential to complement the aforementioned standard procedures to cure colon cancer or improve the life span of an individual. Given the crucial association between miRNAs and cancer, several studies have classified different types of human cancers based on miRNA expression profiles [6,7]. Expression profiling of miRNAs have been carried out in the last decade in colon cancer cell lines or tissues and these studies have established that aberrant expression of miRNAs is associated with colon or colorectal cancer. In this study, we carried out expression profiling of miR-96, miR-422a and miR-584 in colon cancer and show that all the three miRNAs are downregulated. RNA was extracted from the normal mucosa and the cancerous tissue samples according to the following procedure. The total RNA was eluted in 50 μL of DPEC treated water and quantified on a NanoDrop 1000 (Thermo Scientific, USA)

RESULTS

DISCUSSION

CONCLUSION

Conflict of Interest