PT - JOURNAL ARTICLE AU - Hordijk, Peter L. AU - ten Klooster, Jean Paul AU - van der Kammen, Rob A. AU - Michiels, Frits AU - Oomen, Lauran C. J. M. AU - Collard, John G. TI - Inhibition of Invasion of Epithelial Cells by Tiam1-Rac Signaling AID - 10.1126/science.278.5342.1464 DP - 1997 Nov 21 TA - Science PG - 1464--1466 VI - 278 IP - 5342 4099 - http://science.sciencemag.org/content/278/5342/1464.short 4100 - http://science.sciencemag.org/content/278/5342/1464.full SO - Science1997 Nov 21; 278 AB - Tiam1 encodes an exchange factor for the Rho-like guanosine triphosphatase Rac. Both Tiam1 and activated RacV12 promote invasiveness of T lymphoma cells. In epithelial Madin–Darby canine kidney (MDCK) cells, Tiam1 localized to adherens junctions. Ectopic expression of Tiam1 or RacV12 inhibited hepatocyte growth factor–induced scattering by increasing E-cadherin–mediated cell-cell adhesion accompanied by actin polymerization at cell-cell contacts. In Ras-transformed MDCK cells, expression of Tiam1 or RacV12 restored E-cadherin–mediated adhesion, resulting in phenotypic reversion and loss of invasiveness. These data suggest an invasion-suppressor role for Tiam1 and Rac in epithelial cells.