IDH1 and glioblastoma: Due to this influence, a subset of GBM shows Glioma CpG Island Methylation Phenotype (G‐CIMP).4 GBM patients with IDH1 mutations or those belonging to the G‐CIMP phenotype have significantly improved OS.5 Besides, MGMT promoter methylation is also a powerful and independent indicator of therapeutic responses among GBM patients who received chemotherapy with alkylating agents.6 However, these markers have their own limitations in clinical use.