Tumor angiogenesis is an essential process for tumor development by forming blood vessel labyrinth to deliver oxygen and energy and support cancer cells proliferation, as well as promote cancer metastasis.Our previous studies showed that anti-CD 146 mAb, AA98, could inhibit tumor angiogenesis both in vivo and in vitro through suppressing NFκB nuclear translocation in endothelial cells.However, whether and how CD 146 contributes to tumor angiogenesis are still unclear.