The antitumor effect of the novel cancer-specific adenovirus Ad-VEGFR on bladder cancer in vitro and in vivo

Bladder cancer is one of the most common cancers. Approaches that block tumor angiogenesis are a new therapeutic strategy for locally advanced or metastatic BC. VEGF/VEGFR signaling has been obviously and negatively correlated with the progression and invasion of cancer. In this study, we constructed the recombinant adenovirus vAd-VEGFR-3 to investigate its antitumor effector in vitro/vivo. First, we used the recombinant adenovirus vAd-VEGFR-3 to infect bladder cancer cells and then collected the cell culture supernatant to treat human umbilical vein endothelial cells (HUVECs). The proliferation, migration and apoptosis of HUVECs were respectively detected by MTT, transwell and Annexin V-FITC/PI double staining. In addition, mouse bladder mucosa was injured by trypsin, and the orthotopic transplantation model of human bladder cancer was successfully constructed to clarify the anti-tumor effect of Ad-VEGFR in vivo. The results showed that Ad-VEGFR could inhibit the cancer’s proliferation and migration, while promoting the apoptosis of HUVECs in vitro. Moreover, Ad-VEGFR could significantly promote the apoptosis of bladder cancer cells and then prevent tumor growth in vivo. In addition, it also down-regulated the expression levels of CD31, an endothelial cell marker which is closely related to the angiogenesis. Taken together, it suggests that the infection of adenovirus-carrying VEGFR in bladder cancer cells may inhibit blood vessel formation and prevent tumor progression.