Despite significant survival-prolonged benefits,1,220 TMZ treatment promotes GBM gain by more than 10 times mutations stochastically at recurrence (mainly C>T transitions),29,98 including the DNA mismatch repair (MMR)-encoding genes (MSH2, MSH5, MSH6, MHS4, MLH1, MLH2, PMS1, and PMS2),221 whose deficiency contributes to post-treatment hypermutation222 and TMZ resistance.223. This evidence concerns the gene PMS1 and glioblastoma.