PECAM1 and neoplasm: Analysis of CD31 immunochemical staining indicated that a significant reduction of MVD was observed in the tumor tissues from groups treated with HPEI+FILIP1LΔC103-p or DDP alone compared with untreated or HPEI+E-p group (p<0.01, Figure 3A), and the most significant reduction of MVD in the tumor sections was observed from mice received the HPEI+FILIP1LΔC103-p plus DDP combination therapy compared with HPEI+FILIP1LΔC103-p or DDP alone (P<0.01).