MicroRNA-325 Is a Potential Biomarker and Tumor Regulator in Human Bladder Cancer

PURPOSE: We evaluated whether human microRNA-325 may be a potential biomarker and tumor regulator in bladder cancer. METHODS: Human microRNA-325 expression was probed by quantitative real-time polymerase chain reaction in both in vitro bladder cancer cell lines and in vivo bladder carcinoma tissues retrieved from patients with cancer. The prognostic potential of human microRNA-325 in predicting postoperative overall survival of patients with bladder cancer was estimated. Endogenous human microRNA-325 was overexpressed by lentiviral transduction in bladder cancer cell lines, T24 and 5637 cells. The tumor regulatory effects of human microRNA-325 upregulation on T24 and 5637 cells were evaluated both in vitro and in vivo. RESULTS: Human microRNA-325 was aberrantly downregulated in both bladder cell lines and human bladder carcinomas. Lowly expressed human microRNA-325 in bladder carcinoma was closely associated with poor postoperative overall survival of patients with cancer. In T24 and 5637 cells, virally transduced cells had markedly upregulated human microRNA-325 expressions. Biochemical assays demonstrated that human microRNA-325 upregulation in bladder cancer had tumor-suppressive functions by decreasing cancer proliferation, cisplatin chemoresistance, and cancer migration in vitro and hindering transplantation growth in vivo and cell cycle transition. CONCLUSION: Human microRNA-325 is lowly expressed and may serve as a potential prognostic biomarker in human bladder cancer. After further validation, human microRNA-325 may be a novel therapeutic target for suppressing carcinoma in patients with bladder cancer.