EphB4 is a member of the largest known family of receptor protein tyrosine kinases, which plays an important role in angiogenesis and vascular network assembly. EphB4 is normally expressed on venous endothelial cells, while its exclusive ligand, EphrinB2, is expressed on arterial endothelial cells as a transmembrane protein as well. Aberrant expression of EphB4 has been observed in several tumor cell types, although its role in tumor cell biology remains to be fully elucidated. EphB4 activation leads to a number of downstream effects, which influence cell attachment, migration and interaction with ligand-expressing cells. Inhibition of binding of EphB4 to its ligand prevents downstream effects of receptor activation.
Xia G, et al. EphB4 receptor tyrosine kinase is expressed in bladder cancer and provides signals for cell survival[J]. Oncogene, 2006, 25(5): 769.