RNF7-Mediated ROS Targets Malignant Phenotype and Radiotherapy Sensitivity in Glioma With Different IDH1 Genotypes.

Abstract

RNF7 (Ring Finger Protein 7) is a key component of CRLs (Cullin-RING-type E3 ubiquitin ligases) and has been found to possess intrinsic anti-ROS capabilities. Aberrant expression of RNF7 has been observed in various tumor types and is known to significantly influence tumor initiation and progression. However, the specific role of RNF7 in glioblastoma remains unclear. IDH (isocitrate dehydrogenase) mutations, which induce metabolic reprogramming and result in notable heterogeneity among glioma with different IDH genotypes. Through analysis of public glioma databases, we identified a high expression of RNF7 in glioma and its correlation with patient prognosis. Moreover, we observed variations in RNF7 expression and its association with patient outcomes under different treatment modalities among different IDH genotypes. In this study, we demonstrated the critical role of RNF7 in the malignant phenotype of IDH1-mutant glioma and its contribution to radiation resistance. Subsequent functional enrichment analysis of RNF7 in glioma, coupled with validation through cellular experiments, confirmed its significant involvement in maintaining redox balance. Our findings suggest that RNF7 exerts a buffering effect against radiation-induced oxidative stress and counterbalances the redox stress induced by IDH1 mutation through its anti-ROS activity. Additionally, our follow-up investigations revealed that the upregulation of RNF7 after radiation exposure and in IDH1-mutant glioma cells is induced by ROS. Collectively, our study underscores the potential of RNF7 as a molecular biomarker in glioma. Elevated RNF7 expression often indicates a heightened metabolic resilience in glioma, leading to resistance against radiotherapy.