In CT26 colon cancer model, ansofaxine hydrochloride enhanced the proportion of CD8+T cells in spleen, decreased the proportion of tumor infiltration exhausted CD8+T cells, and increased the proportion of natural killer cells (NKs) and M1 macrophages in spleen and tumor, which may be due to the enhancement of peripheral dopamine (DA) and the reduction of peripheral 5-hydroxytryptamine (5-HT), ultimately inhibited tumor growth. Here, CD8A is linked to malignant colon neoplasm.