Abstract
Growing evidence shows that miRNA plays an important role in the development and progression of cancer. In this study, we found that the expression levels of miR-29 family were dramatically decreased in hepatocellular carcinoma (HCC) cell lines and clinical tissues. Then, we demonstrated that ectopic expression of miR-29 family could significantly suppress cell proliferation and induce apoptosis in HCC cells. Luciferase assay together with western blot assay confirmed that miR-29 family bound directly to the 3'-untranslated region (3'-UTR) of RPS15A and reduced the expression of RPS15A. In addition, the cell cycle related gene including cyclinA, cyclin D1 and p21 were also down-regulated when increased the expression of miR-29 family, which is similar as silencing RPS15A expression. Moreover, co-transfection of miR-29 mimics with 3'UTR-deleted RPS15A could rescue the expressions of cyclin A and cyclin D1 while down-regulate the p21 expression. In conclusion, miR-29 family functions as a novel tumor suppressor in HCC by regulate cell growth and cell cycle through binding to RPS15A 3'UTR. These findings may be utilized in developing novel therapeutic tools for HCC.