Gastrin mediated cholecystokinin-2 receptor activation induces loss of cell adhesion and scattering in epithelial MDCK cells.
The presence of gastrin and CCK-2/gastrin receptors in human preneoplastic and neoplastic lesions of pancreas and colon suggests a role in cancer development. Gastrin's growth-promoting action has been established, but a role in cellular morphogenetic processes promoting tumor invasion has been elusive. Our aim was (i) to investigate whether activation of the CCK-2R affects cellular morphology, intercellular adhesion and motility, as crucial parameters of epithelial differentiation, and (ii) to identify the signaling pathways and mechanisms implicated. Madin-Darby Canine Kidney (MDCK) cells were chosen to generate an epithelial non-tumorigenic model system expressing human CCK-2R. Epithelial differentiation and motility were analysed upon CCK-2R activation using immunocytochemistry and invasion assays. The functionality of adhesion complexes and activity of signaling proteins was determined with biochemical techniques. CCK-2R activation induced cell dissociation and enhanced invasion, preceded by decreased membrane localization of adherens junction molecules and nuclear accumulation of beta-catenin. Concomitantly, and requiring the activation of several signaling pathways, catenins were shifted from the cytoskeletal to the cytoplasmic fraction, suggesting the detachment of the cytoskeleton from the adherens complex. These data represent the first evidence for the CCK-2R, regulating cell-cell and cell-substrate adhesion and support a role for CCK-2R in the progression of carcinoma.
Bierkamp
Christiane
C
Institut National de la Santé et la Recherche Médicale (INSERM) U531, Department de Biologie et Pathologie Digestive; Institut Louis Bugnard, CHU Rangueil, 31403 Toulouse, France. Bierkamc@toulouse.inserm.fr
Kowalski-Chauvel
Aline
A
Dehez
Stephanie
S
Fourmy
Daniel
D
Pradayrol
Lucien
L
Seva
Catherine
C
D000081:Acetamides / Q000494:pharmacology; D022005:Adherens Junctions / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology; D015820:Cadherins / Q000187:drug effects / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D004285:Dogs; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005755:Gastrins / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D007668:Kidney / Q000166:cytology; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism; D010671:Phenylurea Compounds / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000187:drug effects / Q000378:metabolism; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D016596:Vinculin / Q000187:drug effects / Q000378:metabolism; D019061:src-Family Kinases / Q000187:drug effects / Q000378:metabolism
D000081:Acetamides; D001570:Benzodiazepinones; D015820:Cadherins; D005755:Gastrins; D010671:Phenylurea Compounds; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin; D016596:Vinculin; C058121:L 365260; C091411:RP 72540; D019869:Phosphatidylinositol 3-Kinases; D019061:src-Family Kinases; D020928:Mitogen-Activated Protein Kinases