Induction effect of MicroRNA-449a on glioma cell proliferation and inhibition on glioma cell apoptosis by promoting PKCα

OBJECTIVE: This study aimed to investigate the expression of microRNA-449a in brain tissue and plasma of patients with glioma and its mechanism of action on glioma cell proliferation and apoptosis. PATIENTS AND METHODS: 30 cases of gliomas patients were recruited in the study, 12 cases in which with brain tissues excision due to decompression or exposure during the brain surgery were selected as the control group. RT-PCR was used to detect the microRNA-449a expression in brain tissue and peripheral blood of the two groups. Cell proliferation and apoptosis level were further determined after high or low expression of microRNA-145 in human glioma cell line U-251. RTPCR and Western blotting were used to detect PKC alpha-mRNA and protein level in U-251. RESULTS: The expression of microRNA-449a in brain tissue or peripheral blood of patients with brain glioma was significantly lower than that of normal people, and the differences were statistically significant (p < 0.05). Upon interfering with microRNA-449a, the glioma cell proliferation was significantly increased while apoptosis was significantly reduced, the PKC alpha protein levels were increased significantly and the differences were statistically significant (all p < 0.05); after overexpression of microRNA-449a, the glioma cell proliferation was significantly decreased while the cell apoptosis was significantly increased, the PKC alpha protein levels were decreased significantly and the differences were statistically significant (all p < 0.05). CONCLUSIONS: The expression of microRNA-449a is low in patients with glioma, which may inhibit the proliferation of glioma and promote its cell apoptosis via affecting the expression of PKC alpha.