One major mechanism that leads to TMZ resistance in GBM is the absence of the MMR system and MLH1 deficiency can confer GBM TMZ resistance.[17] ChIP‐qPCR assay results revealed no markedly difference of H3K9la in the MLH1 promoter in the TMZ‐resistant cells compared to parental cells (Figure S6B, Supporting Information). Here, MLH1 is linked to glioblastoma.