To investigate the effect of hyperglycemia on anti-tumor function induced by anti-PD-1 antibody treatment, we treated STZ-induced diabetic mice with subcutaneous MC38 colon carcinoma tumors with anti-PD-1 antibody, and examined changes in tumor growth, the number of tumor-infiltrating immune cells, and the expression of chemokines and chemokine receptors. Here, PDCD1 is linked to colon carcinoma.