would be linked with a participation in the assembly, disassembly, and signaling of focal adhesions, in which integrin-β3 clustering induced by FN and activation of adaptor pro- teins, including focal adhesion kinase (FAK) and paxillin that interact with cytoskeletal pro- teins such as microtubules and actin microfil- aments, are required.23-27 Moreover, consider- ing that inmunoreactivities observed for inte- grin-β3 and p-FAK in separating, detaching and migrating cells, resembled to that observed for endocan. As suggested, the function of DS-chain of endocan is to bind some growth factors and cytokines as well as ECM molecules including FN and collagen, but the functional signifi- cance of its EGF-like is not yet fully under- stood.15 It is likely that endocan, through its EGF-like domain, directly binds to integrin-β3, a cell surface receptor that is present on the apical side of endothelial cells,28,29 and that this binding occurs in the presence of divalent cations, considering that endocan interacts physically and functionally with the integrin lymphocyte function associated-antigen-1 (LFA-1), present in leukocyte and Jurkat cells, through its polypeptide moiety13 and that the binding of growth factors containing EGF-like motifs to integrin α5β3 occurs via its EGF-like motif.30 Also, it is possible that endocan through its DS-chain binds to FN, facilitating the endothelial cell adhesion. 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