Prognostic value of miR-339-5p in patients with prostate cancer and its effects on tumor progression.

Prostate cancer places a serious health burden on males. The present study aimed to explore the potential prognostic significance and biological function of microRNA (miR)-339-5p in patients with prostate cancer. The expression of miR-339-5p was detected in prostate cancer tissues and cell lines by using reverse transcription-quantitative PCR. Kaplan-Meier survival curves and Cox regression analyses were used to investigate the prognostic significance of miR-339-5p in prostate cancer. The Cell Counting Kit-8 assay was used to determine the effect of miR-339-5p on prostate cancer cell proliferation. Transwell assays were used to assess the effect of miR-339-5p on cell migration and invasion. The results indicated that the expression of miR-339-5p was downregulated in prostate cancer tissues and cell lines. Downregulation of miR-339-5p was significantly associated with the Gleason score, lymph node metastasis and TNM stage. Patients with high miR-339-5p expression levels had a longer survival time than those with low expression levels. Multivariate Cox regression analysis indicated that miR-339-5p may be an independent prognostic factor for the overall survival of patients with prostate cancer. Overexpression of miR-339-5p inhibited the proliferation, migration and invasion of prostate cancer cells. Taken together, these results indicated that miR-339-5p functions as a suppressor gene in prostate cancer and acts by inhibiting cell proliferation, migration and invasion of prostate cancer cells. miR-339-5p may serve as an independent prognostic biomarker and therapeutic target for the treatment of prostate cancer.