MGMT and glioblastoma: Tumors with unmethylated MGMT promoters have a less favorable response to alkylating chemotherapeutic agents4,12,19 due to AGT being actively expressed and repairing the lesions in the DNA caused by treatment.5,10,20–22 Epigenetic silencing of the MGMT gene has also been shown to be associated with decreased mortality and increased progression-free survival (PFS) and overall survival (OS) when compared to glioblastoma patients with unmethylated MGMT promoters.11,13