miR-15a-3p Suppresses Prostate Cancer Cell Proliferation and Invasion by Targeting SLC39A7 Via Downregulating Wnt/β-Catenin Signaling Pathway.

Background: MiR-15a-3p has been reported as a tumor suppressor in several kinds of cancer, including cervical cancer and gastric cancer. However, the precise molecular mechanisms underlying its role in prostate cancer (PCa) remain largely unknown.

Methods: The expression of miR-15a-3p was determined in PCa tissues and cell lines using quantitative real time PCR. The biological function of miR-15a-3p in PCa cells was investigated using a MTT assay, Edu staining and transwell assay. Moreover, luciferase reporter assay, quantitative real time PCR and western blotting were used to identify and verify the direct downstream target of miR-15a-3p.

Results: We found that the expression of miR-15a-3p was down-regulated in both PCa tissues and cell lines. The in vitro results showed that miR-15a-3p overexpression suppressed cell proliferation, invasion, and epithelial-mesenchymal transition (EMT) via down-regulating Wnt/β-catenin signaling in PCa cells. Moreover, SLC39A7 was a direct downstream target of miR-15a-3p. Furthermore, SLC39A7 overexpression attenuated the effects of miR-15a-3p on cell proliferation, invasion, Wnt/β-catenin pathway and EMT molecules.

Conclusions: In summary, our study indicated that miR-15a-3p inhibited the proliferation, invasion, and EMT process of PCa cells via targeting SLC39A7 and suppressing Wnt/β-catenin signaling pathway, which may represent a new therapeutic objective for PCa treatment.