The effects of IDH1 mutation on radiosensitivity of GSCs

• 1、School of Radiation Medicine and Protection , Medical College of Soochow University

Abstract：Objective: To investigate the effects of Isocitrate dehydrogenase 1 (IDH1) gene mutation on radiosensitivity of glioma stem cells (GSCs). Methods: GSCs were enriched and cultured by automated flow cytometry according to CD133, a stem marker of GSCs. The plasmid in which IDH1 gene mutation was overexpressed was constructed and transfected into GSCs, and the expression levels of the mutant protein were detected by Western blot. The effects of IDH1 mutation on the proliferation of GSCs were detected by CCK8 assay. The number of γH2AX foci at different time points after irradiation was detected by cell immunofluorescence technique. The expression of TIGAR protein was detected by Western blot. The redox kit detected the ratios of NADP﹢/NADPH and GSSG/GSH in the control and the experimental groups, respectively. Results: IDH1 mutation on the proliferation of GSCs was not significant by CCK8. Cellular immunofluorescence experiments showed that the amount of γH2AX foci formed in the control group was consistent with that in the experimental group. Western blot results indicated that irradiation caused an increase in TIGAR protein levels, but the amount of protein increased was basically same, The results of redox experiments showed that the reducing substances in the experimental group increased slightly, compared to the control group, but there was no statistical difference. Conclusion: IDH1 gene mutation did not decrease the GSCs` proliferation, DNA damage repair ability, TIGAR protein expression and reducing substances, and the radiation sensitivity ofIDH1 mutant GSCs was not increased after irradiation.

Keywords： radiosensitivity glioma stem cells isocitrate dehydrogenase 1