An evaluation of MGMT promoter methylation within the methylation subclasses of glioblastoma

Methylation analysis is a new powerful tool for the classification of brain tumors. Capper et al. classified glioblastoma (GBM) into K27, G34, RTK I, RTK II, RTK III (pediatric tumors), MYCN (enriched with MYCN amplification), mesenchymal, and midline (sharing epigenetic similarities with H3K27M but lacking this mutation). Here, we illustrate MGMT methylation distribution among each of the before mentioned methylation subclasses of GBM. We observe that most MYCN and RTKIII cases, as well as H3K27M midline gliomas, lack MGMT promoter methylation. More tumors were methylated within RTKI, RTKII, G34, and MID subgroups, whereas more tumors were unmethylated within the MES subgroup.