MiR-515-5p acts as a tumor suppressor via targeting TRIP13 in prostate cancer.

MiR-515-5p has been suggested to function as tumor suppressor in various human cancers. However, the role of miR-515-5p in prostate cancer was still unclear. In this study, we observed miR-515-5p expression was reduced in prostate cancer tissues and prostate cancer cell lines compared with paired adjacent normal prostatic tissues and normal human prostate epithelial cell lines, respectively. Furthermore, we found miR-515-5p was negatively correlated with TRIP13 mRNA and protein expression in prostate cancer tissue samples, and miR-515-5p directly targeted TRIP13 3'-UTR and negatively regulated TRIP13 mRNA and protein expression. Moreover, miR-515-5p acted as a tumor suppressor to regulate cell proliferation, migration and invasion via targeting TRIP13 in prostate cancer. Besides, we observed that miR-515-5p expression in prostate cancer patients with advanced T stage subgroup or high Gleason score was significantly lower than its expression in prostate cancer patients with early T stage or low Gleason score. Survival analysis suggested that prostate cancer cases with high miR-515-5p expression had better prognosis than prostate cancer cases with low miR-515-5p expression. In conclusion, our study highlights the clinical and biological role of miR-515-5p as tumor suppressive microRNA in prostate cancer.