I-Chun Lai et al. discovered that the combined use of the MGMT inhibitor O6-BG and Honokiol can reduce the expression of TMZ-induced Notch3 and Hes1 mRNAs, potentially reversing the resistance of glioblastoma stem-like cells (GBM SP cells) to TMZ [186]. Here, HES1 is linked to glioblastoma.