However, in a mouse model of colon cancer liver metastasis, anti-CTLA-4 therapy significantly increased the number of intra-tumoral CD8+ and CD4+ T cells, reducing the number of Tregs, inducing the production of various pro-inflammatory cytokines, such as IFN-γ, IL-1α, and IL-12, which are associated with CD8+ T cell activation and antitumor response, thereby effectively inhibiting liver metastasis of colon cancer (36). Here, CD4 is linked to malignant colon neoplasm.