CD4 and glioblastoma: In conclusion, our data for the first time, report unique DNA methylation pattern and gene expression profiles in GBM associated tumor infiltrating CD4+ T cells compared to CD4+ T-cell from the blood of the same patient and some of their ligands on the GBM cells suggesting that CD4+ T cells function and differentiation may be influenced by the GBM TME by way of epigenetic mechanisms such as, DNA methylation.