What is MGMT?
Methylguanine Methyltransferase (MGMT) is a DNA repair enzyme.
What does it do?
MGMT reverses the effect of the commonly used oral chemotherapy drug, temozolomide, by repairing the damage inflicted on the tumour DNA by the drug. Temozolomide is used as a standard treatment for high grade glioma (a type of brain tumour), along with radiation therapy, after surgical removal of tumour.
What happens with methylation?
Methylation of the MGMT gene promoter “switches off” the gene that produces the MGMT protein.
How does this improve survival?
Temozolomide is more effective in killing tumour cells (due to lesser DNA repair by MGMT) and this leads to improved survival. In other cases, having a glioma that is MGMT positive is in itself a favourable indicator of better prognosis (even prior to starting on any treatment).
Back