Prophylactic antitumor effects of additional DNA vaccines were significantly improved by the combined vaccination therapy. In prophylactic studies, 10 BALB/c mice per group were immunized with 2 DNA vaccines encoding the idiotype single chain antigen fused to either defensin2β (A) or MIP3α (B), respectively, with or without cardiotoxin, and then challenged with A20 tumor cells as in Figure 1 and followed for survival.