CD274 and central nervous system cancer: Early or late blockade of PD/PD-L1 checkpoint in association with potent T cell immunosuppressors has been demonstrated to neutralize T-cells (i.e. CD8+, CD8+, and CD44 +) subset and diffusion in glioma bearing-mice brain, lymph nodes, and spleens [6], presenting a hopeful treatment for patients with GBM.