Similarly, increased TP53 methylation in the IDH-mutant group did not seem to affect the gene expression, and, furthermore, genes that negatively regulate TP53 (i.e., MDM1, MDM2, and MDM4) were all expressed at significantly lower levels in IDH-mutant glioma than in IDH-wildtype glioma. This evidence concerns the gene IDH2 and central nervous system cancer.