Overexpressing miR-29c targeting AKT2 enhances the radiosensitivity of human hepatocellular carcinoma cell line HepG2 / 中华放射医学与防护杂志

ABSTRACT

Objective To investigate the effect of miR-29c on radiosensitivity of hepatoma HepG2 cells by targeting AKT2 gene.Methods The expression of miR-29c in human normal hepatocytes THLE-3 and hepatoma cell HepG2 was detected by RT-PCR.The relationship between miR-29c and AKT2 were predicted by predicted by informative analysis and verified by dual luciferase reporter gene test and Western blot.miR-29c mimic/AKT2 gene recombinant plasmid and miR-29c inhibitor/ lentivirus vector AKT2 shRNA were transfected into HepG2 cells by Liposome 2000.The cells were irradiated with different doses (0,2,4,6 and 8 Gy) of X-rays,and the effects of miR-29/AKT2 on the survival and cell viability of HepG2 cells were detected by cloning and MTT assays.Results Compared with THLE-3 cells,the expression of miR-29c in HepG2 cells was significantly lower (t=17.816,P＜0.05).After 2,4,6 and 8 Gy X-ray irradiation,the survival of HepG2 cells was significantly lower than that of THLE-3 cells (t =4.541,6.823,7.218,9.363,P＜0.05),and the expression of miR-29c in HepG2 cells was significantly decreased (t =5.599,9.262,10.470,10.873,P＜0.05).The survival and viability of HepG2 cells were decreased by miR-29c overexpression (tsurvival rate =4.307,7.668,7.668,6.894,P＜0.05;tcell viability =3.443,8.116,13.434,P ＜ 0.05) but they were increased by miR-29c inhibition (tsurvival rate =4.003,6.713,7.141,P＜0.05;tcell viability =4.282,5.113,P＜0.05).Double luciferase reporter gene experiments showed that AKT2 was the target gene of miR-29c since the expression of AKT2 was negatively regulated by miR-29c.After the silence of AKT2 or overexpression of AKT2,the survival and viability of HepG2 cells were consistent with the overexpression of miR-29c or the inhibition of miR-29c,respectively.Conclusions MiR-29c increases the radiosensitivity of hepatoma cell HepG2 by targeting AKT2.