Since CXCL9 was expressed in CD11c+ cells, but not in CD8+ T cells, it was suggested that the STZ-induced diabetic condition interferes with the increase of CXCL9 expression detected after anti-PD-1 antibody treatment in CD11c+ cells, which may explain the impaired effect of anti-PD-1 antibody treatment on tumor growth and the decreased number of tumor-infiltrating CD8+ T cells in this model. The gene discussed is CXCL9; the disease is neoplasm.