Many solid tumors establish immune suppression by upregulating the expression of key immune checkpoint receptors (e.g., PD-1, CTLA4) on infiltrating T cells as well as immunosuppressive ligands (e.g., PD-L1, PD-L2, B7-H4), either on tumor cells or other cell types in the tumor microenvironment. Here, CTLA4 is linked to neoplasm.