title: Modulation of endothelial cell migration by extracellular nucleotides: involvement of focal adhesion kinase and phosphatidylinositol 3-kinase-mediated pathways.
abstract: Extracellular nucleotides bind to type-2 purinergic/pyrimidinergic (P2) receptors that mediate various responses, such as cell activation, proliferation and apoptosis, implicated in inflammatory processes. The role of P2 receptors and their associated signal transduction pathways in endothelial cell responses has not been fully investigated. Here, it is shown that stimulation of human umbilical vein endothelial cells (HUVEC) with extracellular ATP or UTP increased intracellular free calcium ion concentrations ([Ca(2+)](i)), induced phosphorylation of focal adhesion kinase (FAK), p130(cas) and paxillin, and caused cytoskeletal rearrangements with consequent cell migration. Furthermore, UTP increased migration of HUVEC in a phosphatidylinositol 3-kinase (PI3-K)-dependent manner. BAPTA or thapsigargin inhibited the extracellular nucleotide-induced increase in [Ca(2+)](i), a response crucial for both FAK phosphorylation and cell migration. Furthermore, long-term exposure of HUVEC to ATP and UTP, agonists of the G protein-coupled P2Y2 and P2Y4 receptor subtypes, caused upregulation of alpha(v) integrin expression, a cell adhesion molecule known to directly interact with P2Y2 receptors. Our results suggest that extracellular nucleotides modulate signaling pathways in HUVEC influencing cell functions, such as cytoskeletal changes, cellular adhesion and motility, typically associated with integrin-activation and the action of growth factors. We propose that P2Y2 and possibly P2Y4 receptors mediate those responses that are important in vascular inflammation, atherosclerosis and angiogenesis.
authors.affiliation: Beth Israel Deaconess Medical Center, Department of Medicine, Harvard Medical School, Boston, MA 02215, USA. ekaczmar@bidmc.harvard.edu
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Kaczmarek
authors.forename: Laurie
authors.initials: L
authors.lastname: Erb
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Koziak
authors.forename: Robert
authors.initials: R
authors.lastname: Jarzyna
authors.forename: Marcia R
authors.initials: MR
authors.lastname: Wink
authors.forename: Olaf
authors.initials: O
authors.lastname: Guckelberger
authors.forename: J Krzysztof
authors.initials: JK
authors.lastname: Blusztajn
authors.forename: Vickery
authors.initials: V
authors.lastname: Trinkaus-Randall
authors.forename: Gary A
authors.initials: GA
authors.lastname: Weisman
authors.forename: Simon C
authors.initials: SC
authors.lastname: Robson
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002448:Cell Adhesion; D002465:Cell Movement / Q000187:drug effects*; D003599:Cytoskeleton / Q000378:metabolism; D042783:Endothelial Cells / Q000502:physiology; D004730:Endothelium, Vascular / Q000166:cytology*; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D006801:Humans; D009711:Nucleotides / Q000494:pharmacology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000502:physiology; D058473:Receptors, Purinergic P2Y2; D015398:Signal Transduction / Q000187:drug effects; D014471:Umbilical Veins; D014544:Uridine Triphosphate / Q000494:pharmacology
chemical_list: D009711:Nucleotides; C546385:P2RY2 protein, human; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; D000255:Adenosine Triphosphate; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human; D002118:Calcium; D014544:Uridine Triphosphate