The miR-203/SNAI2 axis regulates prostate tumor growth, migration, angiogenesis and stemness potentially by modulating GSK-3β/β-CATENIN signal pathway.

Dysregulation of microRNA expression plays a pivotal role in the initiation and progression of a variety of human carcinomas including prostate cancer. Our previous studies have demonstrated that the silence of miR-203 contributes to the invasiveness of malignant breast cancer cells by targeting SNAI2. However, the effects and underlying mechanisms of miR-203/SNAI2 axis in prostate cancer have not been elucidated. The aim of this study is to explore the effects of miR-203/SNAI2 axis on the biological characteristics of prostate carcinomas both in vitro and in vivo. We found that miR-203 was significantly downregulated in prostate cancer cell lines compared with immortalized prostate epithelial cells using semi-quantitative PCR and real-time PCR, as well as in clinical prostate cancer tissues compared to normal tissues using TCGA analysis. Functionally, miR-203 inhibited prostate cancer cell proliferation, migration, endothelial cell tube formation and cancer stemness in vitro. Meanwhile, overexpression of miR-203 suppressed SNAI2 expression both in DU145 and PC3 cells. In addition, the in vivo study showed that miR-203 suppressed tumorigenicity, metastasis and angiogenesis of DU145 cells. Ectopic expression of SNAI2 rescued the inhibitory effects of miR-203 both in vitro and in vivo. Importantly, the EMT markers CDH1 and VIMENTIN were modulated by the miR-203/SNAI2 axis. Furthermore, the GSK-3β/β-CATENIN signal pathway was suppressed by miR-203 and could be reactivated by SNAI2. Taken together, this research unveiled the function of miR-203/SNAI2 axis in tumorigenesis, angiogenesis, stemness, metastasis and GSK-3β/β-CATENIN signal pathway in prostate cancer and gave insights into miR-203/SNAI2-targeting therapy for prostate cancer patients.