RESUMO
OBJECTIVE: To explore the mechanism of miR-124 inhibiting the proliferative activity of prostate cancer PC3 cells. METHODS: Luciferase reporter gene assay was used to examine the specific binding ability of miR-124 to PKM2 mRNA 3'-UTR. After miR-124 was transfected mimic to PC3 cells, the expression levels of PKM2 mRNA and protein were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot, respectively. The effects of miR-124 mimic and PKM2 siRNA on the proliferative activity of the PC3 cells were determined by MTT assay. RESULTS: The expressions of PKM2 mRNA and protein were upregulated (5.12 +/- 0.35) times and (4.05 +/- 0.20) times respectively in the PC3 cells as compared with those in the RWPE-1 cells (P < 0.05). Luciferase reporter gene assay demonstrated that miR-124 targeted PKM2 3'-UTR. At 24 hours after transfection with miR-124 mimic, the PKM2 protein expression in the PC3 cells was downregulated (0.16 +/- 0.04) times (P < 0.05), while the PKM2 mRNA level was not changed significantly (P > 0.05), as compared with the control group. MTT assay showed that both miRNA-124 mimic and PKM2 siRNA could inhibit the proliferation of the PC3 cells, but the former exhibited a greater inhibitory effect than the latter. After transfection with miR-124 mimic and PKM2 siRNA, the cell growth rates were (66.20 +/- 5.10)% vs (82.10 +/- 6.35)% at 24 hours (P < 0.05) and (49.34 +/- 2.37)% vs (70.10 +/- 5.80)% at 48 hours (P < 0.05). CONCLUSION: miR-124 can suppress the proliferation of PC3 cells by regulating the PKM2 gene.