PDCD1 and neoplasm: In the CpG+OX40 aptamer+PD1 aptamer group, the percentage of animals having a tumor at the treatment site was 2.5 times smaller than that in the CpG+OX40 aptamer group (Fig. 5B), while the average tumor size on day 20 was 30 times smaller, compared with the group that received no PD1 aptamers (Fig. 5A).