MicroRNA-195 acts as a tumor suppressor by directly targeting Wnt3a in HepG2 hepatocellular carcinoma cells

Abstract

MicroRNAs (miRNAs) are a class of small, non-coding, endogenous RNAs that are important in tumor cell biological processes as they regulate gene expression. miR-195 has been demonstrated to be a tumor repressor in numerous types of human cancer. However, the mechanism by which miR-195 suppresses tumor development remains to be elucidated. The aim of this study was to investigate the effect of miR-195 on the biological functions of HepG2 hepatocellular carcinoma (HCC) cells and identify the association between miR-195 and Wnt3a in HCC. miR-195 mRNA expression levels in HCC tissues and cell lines were measured by reverse transcription polymerase chain reaction analysis. miR-195 function was measured with cell proliferation, cell cycle and apoptosis assays following transfection with miR-195 and anti-miR-195 sequences, and the respective controls. Luciferase reporter assay was used to determine whether Wnt3a was a target of miR-195. In addition, Wnt3a expression levels were determined in HCC cells using western blot analysis. The miR-195 expression levels were found to be reduced in HCC tissues and cell lines. miR-195 overexpression resulted in a reduction in cell proliferation. In addition, the overexpression of miR-195 in HCC cells induced G1 phase cell cycle arrest and promoted apoptosis. Furthermore, Wnt3a was demonstrated to be directly targeted by miR-195. These findings suggest that miR-195 is key in regulating cell proliferation, cell cycle and apoptosis through targeting Wnt3a. In addition, overexpression of miR-195 may be a potential therapeutic strategy in the treatment of HCC.