title: Thy-1-induced migration inhibition in vascular endothelial cells through reducing the RhoA activity.
abstract: Our previous study indicated that Thy-1, which is expressed on blood vessel endothelium in settings of pathological and a specific of physiological, but not during embryonic, angiogenesis, may be used as a marker for angiogenesis. However, the function of Thy-1 during angiogenesis is still not clear. Here, we demonstrate that knock-down of the endogenous Thy-1 expression by Thy-1 siRNA transfection promoted the migration of human umbilical vein endothelial cells (HUVEC). In contrast, treatment with interleukin-1β (IL-1β) or phorbol-12-myristate-13-acetate (PMA) increased the level of Thy-1 protein and reduced the migration of HUVEC. These effects were abolished by pre-transfection of HUVEC with Thy-1 siRNA to knock-down the expression of Thy-1. Moreover, over-expression of Thy-1 by transfection of HUVEC with Thy-1 pcDNA3.1 decreased the activity of RhoA and Rac-1 and inhibited the adhesion, migration and capillary-like tube formation of these cells. These effects were prevented by co-transfection of the cell with constitutively active RhoA construct (RhoA V14). On the other hand, pre-treatment with a ROCK (a kinase associated with RhoA for transducing RhoA signaling) inhibitor, Y27632, abolished the RhoA V14-induced prevention effect on the Thy-1-induced inhibition of endothelial cell migration and tube formation. Taken together, these results indicate that suppression of the RhoA-mediated pathway might participate in the Thy-1-induced migration inhibition in HUVEC. In the present study, we uncover a completely novel role of Thy-1 in endothelial cell behaviors.
authors.affiliation: Graduate Institute of Medical Sciences, Medical College, Taipei Medical University, Taipei, Taiwan.
authors.forename: Heng-Ching
authors.initials: HC
authors.lastname: Wen
authors.forename: Chieh
authors.initials: C
authors.lastname: Kao
authors.forename: Ruei-Chi
authors.initials: RC
authors.lastname: Hsu
authors.forename: Yen-Nien
authors.initials: YN
authors.lastname: Huo
authors.forename: Pei-Ching
authors.initials: PC
authors.lastname: Ting
authors.forename: Li-Ching
authors.initials: LC
authors.lastname: Chen
authors.forename: Sung-Po
authors.initials: SP
authors.lastname: Hsu
authors.forename: Shu-Hui
authors.initials: SH
authors.lastname: Juan
authors.forename: Wen-Sen
authors.initials: WS
authors.lastname: Lee
mesh_terms: D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D018919:Neovascularization, Physiologic; D011554:Pseudopodia / Q000378:metabolism; D015398:Signal Transduction; D018800:Thy-1 Antigens / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D018800:Thy-1 Antigens; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein