Age-related changes for the predictors of benign prostatic hyperplasia in Chinese men aged 40 years or older.

A cross-sectional study was conducted to estimate the age-stratified normal levels and age-related changes in the risk predictors of benign prostatic hyperplasia (BPH) progression. A total of 4706 male participants aged 40 years or older in Zhengzhou (China) were enrolled. The values of the International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA), prostate volume (PV), and postvoid residual urine volume (PVR) significantly increased with age. Nonlinear relationships between age and IPSS scores ≥8 (P for nonlinearity = 0.046), PSA level ≥1.6 ng ml-1, PV ≥31 ml, or PVR ≥39 ml (all P for nonlinearity <0.001) were observed. After the age of 61 years, the risk indicators related to BPH progression were positively correlated with age (odds ratio [OR] >1), regardless of the predictors of the IPSS score, PSA level, PV, or PVR; and the OR values increased gradually. Therefore, after the age of 61 years, the risk predictors related to BPH progression were positively correlated with age.

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<0.05). SIRT1 expression levels in PC-3 cells with over-expression of miR-34a were significantly reduced compared with those in the negative control (P<0.05). The over-expression of miR-34a inhibited PC-3 cells growth and resulted in increased cell cycle arrest compared with the negative control (P<0.05). In conclusion, miR-34a inhibits the human prostate cancer cell proliferation, in part, through the downregulation of SIRT1 expression.