PER2/SIRT6复合体调控IDH1R132H胶质瘤细胞干性增强放疗敏感性的机制研究

IDH1R132H突变抑制胶质瘤细胞的干性进而增强胶质瘤细胞放化疗敏感性，但其机制尚不清楚。本课题组率先在人胶质瘤细胞中发现PER2和SIRT6在IDH1R132H突变型胶质瘤中表达高于IDH1野生型；而SIRT6可通过去乙酰化修饰促进PER2稳定表达，且敲除IDH1R132H突变型胶质瘤细胞中SIRT6可抑制PER2表达。RNA-seq显示PER2抑制胶质瘤干细胞关键调控基因DNA结合蛋白抑制子1和3(ID1，ID3)的表达。前期研究显示PER2过表达胶质瘤细胞裸鼠移植瘤具有更高的放疗敏感性。故提出在IDH1R132H突变型胶质瘤中PER2/SIRT6复合体抑制ID1和ID3的转录从而增强放疗敏感性的科学假设。通过CRISPER/Cas9，Co-IP、ChIP、报告基因等方法明确PER2在IDH1R132H突变型胶质瘤细胞干性调控网络中的机制，证实PER2可作为胶质瘤精准治疗的可选靶点。

R132H IDH1 mutations inhibit the stemness of glioma cells and then enhance the chemoradiotherapy sensitivity of glioma cells, but the detailed mechanism remains elusvie. Our findings implicate that the PER2 and SIRT6 expression levels are higher in R132H IDH1 mutant gliomas than that in IDH1 wild type human glioma samples. SIRT6 could stabilize PER2 and in turn promote its function through deacetylation modification. Whereas knock-down of SIRT6 in R132H IDH1 mutant glioma cells could inhibit the PER2 expression level. RNA-sequence analysis indicates that PER2 suppresses the expression of key regulatory genes DNA binding protein inhibitor 1/3 (ID1, ID3) in glioma stem cells. Our results show higher radiosensitivity in PER2 overexpressing glioma cell xenografts in nude mice. Hence, we propose the hypothesis that PER2/SIRT6 complex might inhibit the transcription of ID1 and ID3, and enhance the sensitivity to radiation. In this study, we aim to clarify the function and the underlying mechanism of PER2 in regulatory network of R132H IDH1 mutant glioma cells through molecular technologies such as CRISPER/Cas9, Co-IP, Ch-IP, Luciferase reporter assay, etc. We also want to confirm that PER2 could be an optional target for precise treatment of gliomas.