title: Tenascin-C blocks cell-cycle progression of anchorage-dependent fibroblasts on fibronectin through inhibition of syndecan-4.
abstract: Tenascin-C is an adhesion-modulatory extracellular matrix protein that is predominantly expressed during embryonic development, wound healing and in tumor stroma. Here we report that anchorage-dependent human, rat and mouse fibroblasts adhere poorly and fail to proliferate on pure tenascin-C. This was due to a significant reduction of cyclin-dependent kinase 2 (cdk2) activity, resulting from elevated expression and association of the cdk inhibitors (CKIs) p21Cip1 and p27Kip1. To analyse the effect of tenascin-C on fibronectin-mediated adhesion, cells were plated on a mixed fibronectin/tenascin-C substratum. Compared to fibronectin alone, cell spreading and adhesion signaling were compromised, as determined by delayed phosphorylation kinetics of focal adhesion kinase (FAK). Despite the presence of growth factors, these cells remained arrested in the G1 phase of the cell cycle. In contrast to cells plated on pure tenascin-C, cdk2 activity appeared to be inhibited independently of CKIs. Interestingly, overexpression of the transmembrane proteoglycan syndecan-4 restored cell spreading, adhesion signaling and DNA replication on the fibronectin/tenascin-C substratum. A similar rescue was observed using a recombinant peptide that spans the syndecan-4-binding site in fibronectin. This indicates that tenascin-C causes cell cycle arrest and cdk2 inactivation by interfering with fibronectin-syndecan-4 interactions. We therefore propose that syndecan-4 signaling plays a central role in the control of cellular proliferation of anchorage-dependent fibroblasts.
authors.affiliation: Friedrich Miescher Institute for Biomedical Research, Novartis Forschungsstiftung, PO Box 2543, CH-4002 Basel, Switzerland. Gertraud.Orend@unibas.ch
authors.forename: Gertraud
authors.initials: G
authors.lastname: Orend
authors.forename: Wentao
authors.initials: W
authors.lastname: Huang
authors.forename: Monilola A
authors.initials: MA
authors.lastname: Olayioye
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Hynes
authors.forename: Ruth
authors.initials: R
authors.lastname: Chiquet-Ehrismann
mesh_terms: D016475:3T3 Cells / Q000166:cytology / Q000187:drug effects; D000595:Amino Acid Sequence; D000818:Animals; D042846:CDC2-CDC28 Kinases; D002448:Cell Adhesion / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects*; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics; D048429:Cell Size; D002645:Chickens; D003470:Culture Media; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D016213:Cyclins / Q000096:biosynthesis / Q000235:genetics; D004261:DNA Replication / Q000187:drug effects; D016326:Extracellular Matrix Proteins / Q000502:physiology; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D005353:Fibronectins / Q000494:pharmacology*; D016193:G1 Phase / Q000187:drug effects; D006801:Humans; D008562:Membrane Glycoproteins / Q000037:antagonists & inhibitors* / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011509:Proteoglycans / Q000037:antagonists & inhibitors* / Q000502:physiology; D011518:Proto-Oncogene Proteins; D051381:Rats; D053671:Syndecan-4; D019063:Tenascin / Q000494:pharmacology*; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: C493956:CDKN1A protein, human; C493957:Cdkn1a protein, mouse; C493958:Cdkn1a protein, rat; C493961:Cdkn1b protein, mouse; C493962:Cdkn1b protein, rat; D018797:Cell Cycle Proteins; D003470:Culture Media; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D008562:Membrane Glycoproteins; D010446:Peptide Fragments; D011509:Proteoglycans; D011518:Proto-Oncogene Proteins; C508304:SDC4 protein, human; C508306:Sdc4 protein, mouse; C508307:Sdc4 protein, rat; D053671:Syndecan-4; D019063:Tenascin; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C495900:CDK4 protein, human; C495893:Cdk2 protein, mouse; C495892:Cdk2 protein, rat; C495902:Cdk4 protein, mouse; C495903:Cdk4 protein, rat; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases