title: Transglutaminase stabilizes melanoma adhesion under laminar flow.
abstract: To resist substantial wall shear stress (WSS) exerted by flowing blood, metastatic melanoma cells can form adhesive contacts with subendothelial extracellular matrix proteins, such as fibronectin (FN). Such contacts may be stabilized by transglutaminase catalyzed-cross-linkage of cell focal adhesion proteins. We analyzed human melanoma cell adhesion under flow by decreasing the flow (WSS) of melanoma cell suspensions and allowing them to adhere to immobilized wheat germ agglutinin or FN. At the wall shear adhesion threshold (WSAT), cell adherence was rapid with no rolling. Following cell adherence, we increased the flow and determined the wall shear detachment threshold (WSDeT). Cells spread and remained adherent on immobilized FN at high WSDeTs (greater than or equal to 32.5 dynes/cm2). The high resistance of adherent cells to shear forces suggested that transglutaminase-mediated crosslinking might be involved. Transglutaminase inhibitors monodansylcadaverine and INO-3178 decreased WSAT, and at low concentrations completely inhibited tumor cell spreading and promoted detachment at low WSDeTs (0.67 dynes/cm2). In static adhesion assays, transglutaminase inhibitors decreased cell adhesion to immobilized-FN in a dose-dependent manner and prevented the formation of crosslinked 125I-FN complex that failed to enter a SDS-polyacrylamide gradient gel. The data suggest that transglutaminase-catalyzed crosslinking, particularly in the presence of WSS, may be important in stabilizing cellular adhesive contacts during adhesion to immobilized-FN.
authors.affiliation: Department of Tumor Biology, University of Texas, M. D. Anderson Cancer Center, Houston.
authors.forename: D G
authors.initials: DG
authors.lastname: Menter
authors.forename: J T
authors.initials: JT
authors.lastname: Patton
authors.forename: T V
authors.initials: TV
authors.lastname: Updyke
authors.forename: R S
authors.initials: RS
authors.lastname: Kerbel
authors.forename: M
authors.initials: M
authors.lastname: Maamer
authors.forename: L V
authors.initials: LV
authors.lastname: McIntire
authors.forename: G L
authors.initials: GL
authors.lastname: Nicolson
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology; D001345:Autoradiography; D002103:Cadaverine / Q000031:analogs & derivatives / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D016923:Cell Death / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005353:Fibronectins / Q000494:pharmacology; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008545:Melanoma / Q000473:pathology* / Q000503:physiopathology; D013314:Stress, Mechanical; D013876:Thiophenes / Q000494:pharmacology; D011503:Transglutaminases / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology
chemical_list: D000970:Antineoplastic Agents; D005353:Fibronectins; D007457:Iodine Radioisotopes; D013876:Thiophenes; C051179:2-(3-(diallylamino)propionyl)benzothiophene; D011503:Transglutaminases; C008542:monodansylcadaverine; D002103:Cadaverine