As it is evidenced that several genes (including TP53, BRCA1 etc.)are regulated by DNA methylation in other cancers [34–37] we also believe altering the DNA methylation in the tumor infiltrating CD4+ T cells, especially the key lineage specific transcription factors and key cytokines is an inherent characteristic of GBM to regulate effector phenotypes in these cells. This evidence concerns the gene BRCA1 and cancer.