miR-34a inhibits cell proliferation in prostate cancer by downregulation of SIRT1 expression

MicroRNA-34a (miR-34a) functions as a tumor suppressor gene and inhibits abnormal cell growth by regulating the expression of other genes. The role of miR-34a in regulating sirtuin 1 (SIRT1) in prostate cancer remains unclear. The objective of the present study was to investigate the biological function and molecular mechanisms of miR-34a regulation of SIRT1 in human prostate cancer samples and the human prostate cancer cell line, PC-3. Fresh prostate tissues were obtained from patients, and the miR-34a expression in prostate cancer tissues was measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). qPCR and western blotting were performed to assess the effects of miR-34a overexpression on SIRT1 regulation in PC-3 cells, and the cell growth was assessed by Cell Counting Kit-8 (CCK-8). Flow cytometry was used to assess the cell cycle status of the cells. The miR-34a expression levels in prostate cancer tissues were significantly reduced compared with adjacent normal prostate tissues (P