To evaluate whether active immunization with PD1-derived mimotopes induces an anti-tumor effect, the BALB/c mice, engrafted with the syngeneic tumor cell line D2F2/E2 expressing human Her-2/neu, were immunized with the mimotope JT–mPD1 (conjugated to CRM197 in conjunction with Montanide; 25 μg/dose) (Figure 4A). This evidence concerns the gene PDCD1 and neoplasm.