MGMT and glioblastoma: For enhancer 1 (CpG 12, CpG 13, and CpG 18) and enhancer 2 (mean methylation of CpGs 05–08, CpGs 11–14, CpGs 15–18, and CpGs 37–39 as well as ten individual CpGs), the two enhancers being closest to Ki-67, we found significantly positive correlation between enhancer methylation and Ki-67 index, but exclusively for GBM samples with an unmethylated MGMT promoter.