title: Pleiotrophin-induced endothelial cell migration is regulated by xanthine oxidase-mediated generation of reactive oxygen species.
abstract: Pleiotrophin (PTN) is a heparin-binding growth factor that induces cell migration through binding to its receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ) and integrin alpha v beta 3 (ανβ3). In the present work, we studied the effect of PTN on the generation of reactive oxygen species (ROS) in human endothelial cells and the involvement of ROS in PTN-induced cell migration. Exogenous PTN significantly increased ROS levels in a concentration and time-dependent manner in both human endothelial and prostate cancer cells, while knockdown of endogenous PTN expression in prostate cancer cells significantly down-regulated ROS production. Suppression of RPTPβ/ζ through genetic and pharmacological approaches, or inhibition of c-src kinase activity abolished PTN-induced ROS generation. A synthetic peptide that blocks PTN-ανβ3 interaction abolished PTN-induced ROS generation, suggesting that ανβ3 is also involved. The latter was confirmed in CHO cells that do not express β3 or over-express wild-type β3 or mutant β3Y773F/Y785F. PTN increased ROS generation in cells expressing wild-type β3 but not in cells not expressing or expressing mutant β3. Phosphoinositide 3-kinase (PI3K) or Erk1/2 inhibition suppressed PTN-induced ROS production, suggesting that ROS production lays down-stream of PI3K or Erk1/2 activation by PTN. Finally, ROS scavenging and xanthine oxidase inhibition completely abolished both PTN-induced ROS generation and cell migration, while NADPH oxidase inhibition had no effect. Collectively, these data suggest that xanthine oxidase-mediated ROS production is required for PTN-induced cell migration through the cell membrane functional complex of ανβ3 and RPTPβ/ζ and activation of c-src, PI3K and ERK1/2 kinases.
authors.affiliation: Laboratory of Molecular Pharmacology, Department of Pharmacy, University of Patras, GR26504 Patras, Greece.
authors.forename: Sotiria
authors.initials: S
authors.lastname: Tsirmoula
authors.affiliation: Laboratory of Molecular Pharmacology, Department of Pharmacy, University of Patras, GR26504 Patras, Greece.
authors.forename: Margarita
authors.initials: M
authors.lastname: Lamprou
authors.affiliation: Laboratory of Molecular Pharmacology, Department of Pharmacy, University of Patras, GR26504 Patras, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Hatziapostolou
authors.affiliation: Sino-French Research Centre for Life Sciences and Genomics, CNRS/LIA124, Rui Jin Hospital, Jiao Tong University Medical School, 197 Rui Jin Er Road, Shanghai 200025, China.
authors.forename: Nelly
authors.initials: N
authors.lastname: Kieffer
authors.affiliation: Laboratory of Molecular Pharmacology, Department of Pharmacy, University of Patras, GR26504 Patras, Greece. Electronic address: epapad@upatras.gr.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Papadimitriou
mesh_terms: D000818:Animals; D016466:CHO Cells; D000081247:CSK Tyrosine-Protein Kinase; D002352:Carrier Proteins / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002465:Cell Movement; D003412:Cricetulus; D016207:Cytokines / Q000494:pharmacology*; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D008297:Male; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000378:metabolism; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5 / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D014969:Xanthine Oxidase / Q000378:metabolism*; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D000081247:CSK Tyrosine-Protein Kinase; D002352:Carrier Proteins; D016207:Cytokines; D039302:Integrin alphaVbeta3; D019869:Phosphatidylinositol 3-Kinases; D017382:Reactive Oxygen Species; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5; D011994:Recombinant Proteins; D014969:Xanthine Oxidase; D019061:src-Family Kinases; C066845:pleiotrophin; C000631346:CSK protein, human
keywords: Cell migration; PTN; ROS; RPTPβ/ζ; Xanthine oxidase; α(ν)β(3)