Multiple i.v. administrations in OS-RC-2 renal cell carcinoma xenograft-bearing mice successfully induced anti-tumor immune functionality by increasing the number of intratumoral (CD11b+) macrophages and M1 (CD169+) macrophages, repolarizing M1/M2 macrophages, and inhibiting tumor growth, compared with the untreated control group. Here, SIGLEC1 is linked to neoplasm.