title: Focal adhesion kinase mediates defects in the force-dependent reinforcement of initial integrin-cytoskeleton linkages in metastatic colon cancer cell lines.
abstract: Micro-environmental clues, including the biophysical interpretation of the extracellular matrix, are critical to proliferation, apoptosis and migration. Here, we show that metastatic human colon cancer cell lines display altered matrix interaction. Interaction of colon cancer cells with collagen I depends on integrins (mainly alpha(1)/beta(1)) but metastatic cells display delayed spreading and reduced extension of lamellipodia. In addition, cells show defective strengthening of integrin-cytoskeleton linkages upon mechanical stimulation, as determined by laser trapping experiments and binding of large beads to the cell surface. However, adhesion to pliable surfaces is ameliorated in metastatic variants. These changes are caused by constitutive activation of focal adhesion kinase (FAK) and can be modulated by changing expression and/or activity of FAK via RNA-interference or expression of inhibitory constructs, respectively. In addition, consistent with defective strengthening of integrin-cytoskeleton linkages, metastatic cell lines show reduced random motility. Taken together these data suggest that constitutive activation of FAK causes defects in spreading, reinforcement of integrin-cytoskeleton linkages and migration and at the same time could ameliorate the adhesion of metastatic cells to suboptimal surfaces.
authors: Department of Internal Medicine I, University of Ulm, Robert Koch Strasse 8, D-89081 Ulm, Germany. goetz.wichert@uniklinik-ulm.de
authors: Götz
authors: G
authors: von Wichert
authors: Denis
authors: D
authors: Krndija
authors: Heidrun
authors: H
authors: Schmid
authors: Georg
authors: G
authors: von Wichert
authors: Georg
authors: G
authors: Haerter
authors: Guido
authors: G
authors: Adler
authors: Thomas
authors: T
authors: Seufferlein
authors: Michael P
authors: MP
authors: Sheetz
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D003110:Colonic Neoplasms / Q000201:enzymology* / Q000473:pathology; D003599:Cytoskeleton / Q000378:metabolism* / Q000473:pathology; D004789:Enzyme Activation / Q000187:drug effects; D051417:Focal Adhesion Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D039222:Integrin alpha1beta1 / Q000378:metabolism*; D009362:Neoplasm Metastasis; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000494:pharmacology; D013314:Stress, Mechanical
chemical_list: D039222:Integrin alpha1beta1; D034741:RNA, Small Interfering; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human