Identification and mechanism analysis of microRNA-129 target gene mitogen-activated protein kinase 1 in prostate cancer cells

Objective To verify whether mitogen-activated protein kinase 1 (MAPK1) is the target gene of microRNA (miR)-129 in prostate cancer cells, and to explore the corresponding molecular mechanism. Methods Target genes of miR-129 were predicted and screened by bioinformatics software. A target gene 3'untranslated region(3'-UTR) dual luciferase wild-type vector and binding site mutant vectors were constructed, which were co-transfected respectively with the has-miR-129 mimic and scramble mimic into PC-3 cells, and 48 h later the luciferase activities were detected. The mRNA expression levels of target gene were detected by real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) after mimic transfection into PC-3 cells at 48 h. The protein expression levels of target gene and its downstream regulation genes were detected by Western blotting. Results MAPK1 was screened as a possible target gene of miR-129. After miR-129 over-expression, the luciferase activity values of pMIR_MAPK1_WT (0.495±0.070) were significantly lower than those of scramble control groups (1.000±0.128, P 0.05). The mRNA relative expression levels of MAPK1 (0.720±0.041) after miR-129 over-expression was lower than those in scramble control groups (1.000±0.056, P 0.05). Conclusion MAPK1 may be a direct target gene of miR-129. MiR-129 may play anti-tumor roles in prostate cancer cells through inhibiting the activities of MAPK1 signaling pathway. Key words: Prostate cancer; MicroRNA-129; Target gene