MGMT and glioblastoma: Inclusion of AAG and/or Ape1 together with MGMT expression in multivariate models may allow more accurate prediction of clinical response and further the goal of individualizing treatment for GBM, an expectation supported by the stratification of survival based on AAG immunopositivity in both MGMT promoter methylated and unmethylated GBMs (Agnihotri et al., 2012).