Detection of DNA methylated microRNAs in hepatocellular carcinoma

Abstract

Irregular methylation, including DNA hypomethylation and/or promoter gene CpG hypermethylation, is involved in the pathogenesis of several solid tumors, including liver cancer. miRNAs are small, endogenous, noncoding RNAs that serve as posttranscriptional regulators of gene expression. Previous research has focused on identifying the factors that regulate the expression of miRNAs in hepatic carcinogenesis. The factors that regulate miRNA expression are not clear; in particular, the role of DNA methylation, an epigenetic regulatory factor that controls miRNA transcription, has not been clarified. The goal of this study is to explore our understanding of the mechanism by which HCC may develop and progress through identification of the role of epigenetically regulated miRNAs influences in the liver carcinogenesis. The current study included 60 patients who were well diagnosed as HCC patients. 60 patients who suffer from liver cirrhosis were also enrolled in the current study and 30 healthy control subjects who serve as control group. All patients will be subjected to: full clinical assessment, abdominal ultrasound, Blood sample will be withdrawn from every patients for both biochemical and serum detection of microRNAs (191-203 -335) by real time PCR. We found that all studied microRNAs were down regulated among HCC patients when compared to cirrhotic patients and controls (p value: 0.005, 0.005 and 0.001 for microRNAs 191, 203 and 335 respectively). Moreover, these microRNAs can discriminate cases of HCC from risky cirrhotic patients. We can conclude that downregulated microRNAs among HCC cases proposed a pattern to explain the role of DNA methylation on miRNA and gene expression in HCC.