Antitumor effects of anti-PD-1 antibody, CGA, and their combination (Anti-PD-1 antibody, 200 μg per injection, i.p. at 3rd, 7th, 10th day post tumor innoculation; CGA, 50 mg/kg, i.p. for 21 days and 19 days) were examined by measuring tumor growth suppression in two xenografts mice models (Fig. 4A-B and 4F-G). Here, PDCD1 is linked to neoplasm.