Fig 1: The impacts of HSPB2 methylation and expression on TMZ resistance. a HSPB2 overexpression using lentivirus infections was confirmed by western blot in U251 and T98G cells regardless of MGMT expression. b CCK-8 proliferation assays of U251 and T98G cells infected with lentivirus containing human HSPB2 ORF or empty control lentivirus. c, d Flow cytometry and TUNEL assay analysis detecting apoptotic cells in U251 and T98G cells after infections with lentivirus containing human HSPB2 ORF or empty control lentivirus. e CCK-8 assays of U251 and T98G cells with or without HSPB2 overexpression after the treatment of TMZ at 100 µM or an equal volume of DMSO for 7 consecutive days. f The single CpG methylation of HSPB2 by pyrosequencing predicted OS in FFPE samples of IDH1R132H wild-type GBMs treated with the combination of RT and TMZ (left) but not in those with RT alone (right). g Interaction analysis showed that standard RT plus TMZ conferred a clear OS benefit to patients with hypermethylated HSPB2, rather than those with hypomethylated HSPB2, in comparison with standard RT alone. TMZ temozolomide, ORF open reading frame, RT radiotherapy, DMSO dimethyl sulfoxide, OS overall survival, FFPE formalin-fixed paraffin-embedded, GBM glioblastoma