Effect of miR-939-5p on the migration and proliferation of hepatocellular carcinoma by regulating the expression of USP22 gene / 国际外科学杂志

ABSTRACT

Objective To investigate the regulation of miR-939-5p on USP22 gene expression and its effect on liver cancer migration and proliferation.Methods The expression of miR-939-5p in hepatoma cell lines (HepG2,MHCC-97H,SMMC-7721,BEL-7404 and Huh7) and normal liver cell line LO2 was detected by realtime PCR (qPCR).The liver cancer cells with the lowest expression were used as experimental subjects,and transfected with miR-939-5p (Experimental group) or miR-NC (Control group).qPCR was used to detect the transfection efficiency of miR-939-5p.Transwell migration assay and MTT proliferation assay were used to detect the migration and proliferation of hepatoma cells after transfected miR-939-5p.Bioinformatics software predicted target genes for miR-939-5p.The dual luciferase reporter gene verified the interaction of miR-939-5p with the target gene.qPCR and Western blotting were used to detect the expression of target genes at mRNA and protein levels after over-expression of miR-939-5p.Measurement data were expressed as (Mean ± SD),and t test was used for comparison between groups.Results The expression of miR-939-5p was significantly lower in hepatoma cell lines than in normal hepatocytes (P ＜0.01),and the expression of miR-939-5p was the lowest in SMMC-7721 cells (P＜0.01).miR-939-5p was efficiently transfected into SMMC-7721 cells [(1.01 ±0.07) vs (20.12 ± 1.27),P ＜0.01].High expression of miR-939-5p inhibited the migration ability (P ＜ 0.01) and proliferative capacity of liver cancer SMMC-7721 cells (P ＜0.05).The USP22 gene may be a target gene of miR-939-5p.The luciferase reporter gene confirmed that miR-939-5p specifically binds to the 3'-UTR of USP22 mRNA (P ＜ 0.01).USP22 expression was decreased at mRNA and protein levels after high expression of miR-939-5p (P ＜ 0.01).Conclusions The expression of miR-939-5p was down-regulated in hepatocellular carcinoma cell lines,and miR-939-5p inhibited the migration and proliferation of liver cancer SMMC-7721 cells.The molecular mechanism was to interfere with the expression of USP22 gene.