Further studies are necessary to (i) identify the mechanisms of TMZ-induced Cx43/Snail-1 up-regulation in GBM cells, (ii) to scrutinize the interrelations between MGMT and Cx43-dependent GBM drug-resistance, and (iii) to elucidate the contribution of single cell adaptation to TMZ versus selective elimination of drug-sensitive cells by TMZ during the microevolution of GBM lineages. Here, MGMT is linked to glioblastoma.