CTLA4 and neoplasm: Researchers constructed tumor models of CT26 colon cancer and ID8‐VEGF ovarian cancer mice, prepared a gvax vaccine composed of irradiated tumor cells expressing granulocyte‐macrophage colony‐stimulating factor, combined the dual block therapy of PD‐1 and CTLA‐4 with the vaccine, and observed the activation of tumor‐infiltrating lymphocytes in mice, the production of antigen‐specific inflammatory cytokines and the decrease of regulatory T cells.121