In order to target GBM-specific immunosuppressive pathways, creating inverted cytokine receptors with exodomain from the TGF-b receptor or IL-10R and ectodomain from IL-7 or IL-21 might combat the immune-suppressive role of these cytokines as these are abundantly secreted by GBM and play an important role in attenuating T cell effector function. This evidence concerns the gene IL21 and glioblastoma.