IDH3A and central nervous system cancer: Using methylation array data from TCGA low-grade and high-grade gliomas data set, we identified robust VRK2 promoter methylation across subtypes that occurred more frequently in tumors that exhibited isocitrate dehydrogenase (IDH) mutations, O6-methylguanine-DNA methyltransferase (MGMT) methylation, the CpG island methylator phenotype (G-CIMP), or lower grade (Figure 2C).