Methylation of MGMT
Many people are wondering about MGMT and what it means for brain tumor treatment.
MGMT (O-6-methlylguaninine-DNA methlytransferase) is a DNA repair protein which transfers a methyl group from guanine to itself. Methylation of the MGMT promoter within tumor cells prevents expression of MGMT, limiting DNA repair ability of the tumor cell. Methylation of MGMT promoter makes tumor cells more responsive to alkylating agents such as temozolomide, CCNU and BCNU. MGMT methylation is a genetic marker obtained from the tumor biopsy. In gliomas, MGMT promoter methylation is shows longer survival when receiving either radiation or chemotherapy.
MGMT methylation presence or absence is not presently used or approved as part of the treatment. Patients with glioblastoma, or high grade gliomas will usually receive temozolomide regardless of their MGMT methylation status. In the next step towards personalized medicine, MGMT promoter methylation testing will be used as a marker for patient selection within clinical trials.
Mary Lovely, PhD, RN, CNRN