Therefore, the immunosuppressive GBM microenvironment is the main reason for the limited efficacy of immunotherapy in GBM, especially for T cells, including immunosuppressive immune cells (Tregs, MDSCs, and TAMs), tumor cell-derived inhibitory cytokines, and the upregulated expression of immune checkpoint receptors on T cells and PD-L1 on tumor cells. Here, CD274 is linked to glioblastoma.