title: Growth differentiation factor-15 (GDF-15) suppresses in vitro angiogenesis through a novel interaction with connective tissue growth factor (CCN2).
abstract: Growth differentiation factor-15 (GDF-15) and the CCN family member, connective tissue growth factor (CCN2), are associated with cardiac disease, inflammation, and cancer. The precise role and signaling mechanism for these factors in normal and diseased tissues remains elusive. Here we demonstrate an interaction between GDF-15 and CCN2 using yeast two-hybrid assays and have mapped the domain of interaction to the von Willebrand factor type C domain of CCN2. Biochemical pull down assays using secreted GDF-15 and His-tagged CCN2 produced in PC-3 prostate cancer cells confirmed a direct interaction between these proteins. To investigate the functional consequences of this interaction, in vitro angiogenesis assays were performed. We demonstrate that GDF-15 blocks CCN2-mediated tube formation in human umbilical vein endothelial (HUVEC) cells. To examine the molecular mechanism whereby GDF-15 inhibits CCN2-mediated angiogenesis, activation of αV β3 integrins and focal adhesion kinase (FAK) was examined. CCN2-mediated FAK activation was inhibited by GDF-15 and was accompanied by a decrease in αV β3 integrin clustering in HUVEC cells. These results demonstrate, for the first time, a novel signaling pathway for GDF-15 through interaction with the matricellular signaling molecule CCN2. Furthermore, antagonism of CCN2 mediated angiogenesis by GDF-15 may provide insight into the functional role of GDF-15 in disease states.
authors.affiliation: Department of Pathology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado 80045, USA.
authors.forename: Ramon J
authors.initials: RJ
authors.lastname: Whitson
authors.forename: Marshall Scott
authors.initials: MS
authors.lastname: Lucia
authors.forename: James R
authors.initials: JR
authors.lastname: Lambert
mesh_terms: D045744:Cell Line, Tumor; D055513:Connective Tissue Growth Factor / Q000378:metabolism*; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D022001:Focal Adhesions / Q000378:metabolism; D055436:Growth Differentiation Factor 15 / Q000502:physiology*; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D009369:Neoplasms / Q000098:blood supply; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D015398:Signal Transduction; D020798:Two-Hybrid System Techniques
chemical_list: C526317:CCN2 protein, human; C526140:GDF15 protein, human; D055436:Growth Differentiation Factor 15; D039302:Integrin alphaVbeta3; D055513:Connective Tissue Growth Factor; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human