Jichu yixue yu linchuang (Mar 2020)
miR-150-5p enhances radiotherapy sensitivity of hepatocellular carcinoma cells line HepG2 through targeting SIRT1
Abstract
Objective To investigate the effect on the radiosensitivity enhancement of hepatocellular carcinoma cells by targeting SIRT1 with miR-150-5p. Methods The establishment of radioresistant cell strain RR-HepG2 was induced by fractional incremental radiotherapy. RT-qPCR was used to detect the expression of miR-150-5p in HepG2 and RR-HepG2 at different radiation doses. Cell cloning assay was used to detect the radiosensitivity of the two groups cell at the same radiation dose. Flow cytometry and Western blot were used to detect the effect of over-expression of miR-150-5p on apoptosis of HepG2 cells. Double luciferase assay was used to detect the association between miR-150-5p and SIRT1.Cell cloning and Western blot were used to detect the changes of radiosensitivity and apoptotic protein after over-expression of SIRT1. Results The expression of miR-150-5p in RR-HepG2 group decreased significantly with the same radiation dose(P＜0.05). The survival fraction and sensitivity of cells in agomiR-150-5p group decreased significantly(P＜0.05), the expression of Bax and caspase-9 increased significantly, the expression of Bcl-2 decreased significantly, and the apoptotic rate was significantly increased. The wild type (WT)agomiR-150-5p luciferase activity decreased significantly and SIRT1 protein level decreased significantly(P＜0.05); wild type (WT)anta-agomiR-150-5p luciferase activity increased significantly and SIRT1 protein level increased significantly (P＜0.05); WT-anta-agomiR-150-5p luciferase activity increased significantly and SIRT1 protein level increased significantly (P＜0.05). The survival fraction of cells in the agomiR-150-5p group decreased significantly, the expression of Bax and caspase-9 increased significantly, and the expression of Bcl-2 decreased significantly(P＜0.05). The survival fraction of cells in the agomiR-150-5p+SIRT1 group increased significantly, the expression levels of Bax and caspase-9 decreased significantly, and the expression of Bcl-2 increased significantly(P＜0.05). Conclusions The down-regulation of SIRT1 expression by miR-150-5p improves the radiosensitivity of hepatocellular carcinoma cells and provides a potential target for clinical radiotherapy of hepatocellular carcinoma.
