MicroRNAs: an emerging science in cancer epigenetics

Rishabh Kala,Trygve O Tollefsbol,Tabitha M Hardy,Gregory W Peek

doi:10.1186/2043-9113-3-6

Rishabh Kala, Trygve O Tollefsbol + Show 2 more

Open Access

https://doi.org/10.1186/2043-9113-3-6

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Abstract

MicroRNAs (miRNAs) are remarkable molecules that appear to have a fundamental role in the biology of the cell. They constitute a class of non-protein encoding RNA molecules which have now emerged as key players in regulating the activity of mRNA. miRNAs are small RNAmolecules around 22 nucleotides in length, which affect the activity of specific mRNA, directly degrading it and/or preventing its translation into protein. The science of miRNAs holds them as candidate biomarkers for the early detection and management of cancer. There is also considerable excitement for the use of miRNAs as a novel class of therapeutic targets and as a new class of therapeutic agents for the treatment of cancers. From a clinical perspective, miRNAs can induce a number of effects and may have a diverse application in biomedical research. This review highlights the general mode of action of miRNAs, their biogenesis, the effect of diet on miRNA expression and the impact of miRNAs on cancer epigenetics and drug resistance in various cancers. Further we also provide emphasis on bioinformatics software which can be used to determine potential targets of miRNAs.

Highlights

MicroRNAs are a group of endogenous small and noncoding RNAs that are approximately 18–25 nucleotides in length that play a critical role in the regulation of gene expression
This long primary transcript is further cleaved by Drosha, an RNase III nuclear enzyme which liberates a ~ 60-to 70-nucleotide stem loop intermediate known as the Micro RNA (miRNA) precursor [3,4]
Further activation of miR-34a resulted in inhibition of growth with a decrease in Sirt1 expression. These findings suggest that miR-34a targeting the Sirt1 genes could negatively regulate, at least in part, the resistance to 5-FU in human colorectal cancer DLD-1 cells [41]

Summary

Introduction

MicroRNAs (miRNAs) are a group of endogenous small and noncoding RNAs that are approximately 18–25 nucleotides in length that play a critical role in the regulation of gene expression. In support of a tumor suppressor role of miRNAs, a study was performed on T24 bladder cancer cells in which cells were treated with a DNA demethylating agent and HDAC inhibitors, which resulted in a decrease in DNA methylation and an increase in histone activation around the promoter region of the miR-127 gene. This lead to increased expression of miR-127 and tumor inhibition [46].

Bartel DP

Findings

14. Bartel DP