TP53 and glioblastoma: Zawlik et al. found a significantly higher frequency of TP53 G:C > A:T transition mutations in glioblastomas with MGMT promoter methylation compared with glioblastomas without MGMT promoter methylation, whereas the total frequency of TP53 mutations in glioblastoma with methylated and non-methylated MGMT promoters was similar [17].