MicroRNA-144-3p inhibits cell proliferation and induces cell apoptosis in prostate cancer by targeting CEP55.

Previous research reported that miR-144-3p functions as tumor suppressor in several tumors, including glioblastoma and hepatocelluar carcinoma, but the role of miR-144-3p in prostate cancer (PCa) remains unclear. In this study, we aimed to analyze the role of miR-144-3p in PCa. By RT-qPCR, we found that expression of miR-144-3p was markedly down-regulated in PCa tissues and cell lines compared with that in paired adjacent normal tissues and normal cell lines. Moreover, miR-144-3p overexpression in PC-3 and DU145 cells by transfection with miR-144-3p mimics significantly inhibited cell proliferation and by MTT, colony formation assays and suppressed tumor growth by nude mice model. Flow cytometry analysis further demonstrated that forced expression of miR-144-3p induced cell cycle G1/S phase arrest and apoptosis. Moreover, centrosomal protein of 55 (CEP55) was confirmed as a direct target of miR-144-3p by bioinformatics analysis and luciferase reporter assays. Overexpression of miR-144-3p decreased the CEP5 mRNA and protein levels in PC-3 and DU145 cells. Using Oncomine database analysis, we further found the expression of CEP55 was significantly upregulated in PCa tissues. In addition, knockdown of CEP55 elicited similar effects with miR-144-3p overexpression in PCa cells. Taken together, our results demonstrate that miR-144-3p functions as a tumor suppressor in PCa by downregulating CEP55, supporting the targeting miR-144-3p might be a potentially effective therapeutic approach for PCa.