Regulation of non-coding RNA, microRNA-3182 in Hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the prominent types of primary liver cancer affecting millions of people worldwide. Aberrant expression of non-coding RNAs (ncRNAs) is a key player in regulating hepatocellular HCC. Here, we aimed to identify the role of microRNA-3182 (miR-3182) and long non-coding RNA (lncRNA), mir-497-195 cluster host gene (MIR497HG) in HCC. Computational analysis was used to predict and screen miRNA that regulate MIR497HG and its potential downstream target genes, B-cell lymphoma 2 (Bcl-2) and cyclin D2 (CCND2). The effect of miR-3182 on Bcl-2 and CCND2 expression was further assessed in HCC cell line (HepG2) with miR-3182 mimic and miR-3182 inhibitor to increase and decrease miR-3182 expression, respectively. The cell proliferation was evaluated using MTS assay. Relative expression of miR-3182 and target genes was determined by RT-qPCR. Computational analysis predicted that miR-3182 was targeting MIR497HG, Bcl-2 and CCND2. Expression of miR-3182 was significantly downregulated in HepG2 compared with the WRL-68 cell lines (P<0.05). Meanwhile, the expression of MIR497HG was also significantly downregulated in HepG2 compared with the WRL-68 cell lines (P<0.05). Overexpression of miR-3182 reduced the cell proliferation of HepG2 cells at 24 h post-transfection compared to control (P<0.05). Additionally, overexpression and inhibition of miR-3182 significantly downregulated and upregulated the expression of Bcl-2 and CCCND2 levels in HepG2 cells respectively. It can be concluded that miR-3182 regulates the expression of Bcl-2 and CCND2. miR-3182 may be proposed as a potential therapeutic target for HCC. Taken together, this study provides evidence for post-transcriptional regulation of Bcl-2 and CCND2 by miRNA in HCC cells.