MicroRNA-18b-5p Inhibits the Malignant Progression of Prostate Cancer Through Downregulating TRAF5.

OBJECTIVE: Extensive efforts have been made for translating the mechanisms of microRNAs (miRNAs) in prostate cancer (PCa). However, the specific role of miR-18b-5p in PCa is still in obscurity. Herein, miR-18b-5p/TRAF5 axis-oriented exploration in PCa has been launched. METHODS: miR-18b-5p and TRAF5 expression in PCa tissues and cells was detected by RT-qPCR. In-vitro experiments were conducted to investigate the biological functions of miR-18b-5p and TRAF5 in PCa cells. The underlying mechanism of miR-18b-5p was revealed by luciferase reporter assay, miRNA Pull down, RT-qPCR, and rescue assay. RESULTS: Lower miR-18b-5p and higher TRAF5 expression were observed in PCa tissues and cell lines. miR-18b-5p overexpression or TRAF5 downregulation impaired proliferation, diminished migratory and invasive properties, as well as advanced apoptosis in PCa cells. miR-18b-5p could regulate TRAF5 expression by directly binding to its 3'-untranslated region. Overexpression of TRAF5 abolished the suppressive effects of restored miR-18b-5p on PCa cell progression. CONCLUSION: This study elucidates that upregulated miR-18b-5p impedes PCa cell progression via downregulating TRAF5, which may provide a novel therapeutic basis for PCa.