Role of MGMT in Glioblastomas

The acronym “MGMT” refers to the enzyme methylguanine methyltransferase. This enzyme plays a crucial role in DNA repair by removing methyl groups from methylated guanine bases. In the context of glioblastoma, which is a highly aggressive type of brain cancer, the status of the MGMT gene is of great importance because of its relationship to response to treatment with chemotherapy, specifically the agent temozolomide.

Temozolomide is a drug used in the treatment of glioblastoma, and its efficacy is related to the tumor’s ability to repair the DNA damage induced by the drug. Temozolomide induces DNA damage by adding methyl groups to the guanine bases, leading to the formation of cross-links in the DNA strand and cell death. However, cancer cells with high expression of the MGMT enzyme can repair this damage more efficiently, which decreases the effectiveness of treatment.

In patients with glioblastoma, it has been observed that those whose tumors have high MGMT gene promoter methylation (leading to low expression of the enzyme) have a better response to temozolomide treatment, as the tumor cells are less able to repair the drug-induced DNA damage. Therefore, MGMT gene status in glioblastoma tumors is an important predictive factor for treatment response and patient survival.

In summary, the role of the MGMT gene in glioblastoma is related to its impact on response to temozolomide treatment. Methylation of the MGMT gene promoter may influence the expression of the enzyme and thus the ability of the tumor to repair treatment-induced DNA damage.