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 in vitro by MTT, colony formation assays and suppressed tumor growth in vivo 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.