PT - JOURNAL ARTICLE AU - Fang Tian AU - Cai-hua Zhu AU - Xiong-wen Zhang AU - Xin Xie AU - Xian-liang Xin AU - Yang-hua Yi AU - Li-ping Lin AU - Mei-yu Geng AU - Jian Ding TI - Philinopside E, a New Sulfated Saponin from Sea Cucumber, Blocks the Interaction between Kinase Insert Domain-Containing Receptor (KDR) and α<sub>v</sub>β<sub>3</sub> Integrin via Binding to the Extracellular Domain of KDR AID - 10.1124/mol.107.036350 DP - 2007 Sep 01 TA - Molecular Pharmacology PG - 545--552 VI - 72 IP - 3 4099 - http://molpharm.aspetjournals.org/content/72/3/545.short 4100 - http://molpharm.aspetjournals.org/content/72/3/545.full SO - Mol Pharmacol2007 Sep 01; 72 AB - Vascular endothelial growth factor (VEGF) signaling pathway is essential for tumor angiogenesis and has long been recognized as a promising target for cancer therapy. Current view holds that physical interaction between αvβ3 integrin and kinase insert domain-containing receptor (KDR) is important in regulating angiogenesis and tumor development. We have reported previously that a new marine-derived compound, philinopside E (PE), exhibited the antiangiogenic activity via inhibition on KDR phosphorylation and downstream signaling. Herein, we have further demonstrated that PE specifically interacts with KDR extracellular domain, which is distinct from conventional small-molecule inhibitors targeting cytoplasmic kinase domain, to block its interaction with VEGF and the downstream signaling. We also noted that PE markedly suppresses αvβ3 integrin-driven downstream signaling as a result of disturbance of the physical interaction between KDR and αvβ3 integrin in HMECs, followed by disruption of the actin cytoskeleton organization and decreased cell adhesion to vitronectin. All of these findings substantiate PE to be an unrecognized therapeutic class in tumor angiogenesis and, more importantly, help appeal the interest of the therapeutic potential in angiogenesis and cancer development via targeting integrin-KDR interaction in the future. The American Society for Pharmacology and Experimental Therapeutics