To investigate whether TMZ resistance primarily affects chromatin regulation to increase METTL3 expression, we established a TMZ‐resistant U87MG cell line (U87MG_TMZ_R) and a primary TMZ‐resistant GBM cell line (pGBM_TMZ_R) from a TMZ‐resistant GBM tumor (Figure S2B). Here, METTL3 is linked to glioblastoma.