Figure 4

F-TrCP-Ecad inhibits clonogenic and tumorigenic potential of DLD1 cells. A. βTrCP-Ecad inhibits the growth rate of DLD1 cells. DLD1-F-TrCP-Ecad cells were grown in the presence or the absence of Dox for five days. The numbers of cells were counted daily in triplicates. B. Induction of F-TrCP-Ecad decreases the colony forming ability of DLD1 cells. DLD1-F-TrCP-Ecad cells were diluted, plated at a low density, and cultured in the presence or the absence of Dox for 14 days. Plates were photographed (top panel) and the number of colonies was counted (bottom panel). The experiment was performed in triplicates C. F-TrCP-Ecad induction inhibits tumorigenicity of DLD1 cells in nude mice. 2 × 10⁶ DLD1-F-TrCP-Ecad cells were injected subcutaneously in nude mice. Each mouse received three injections. Nude mice were fed with either regular or Dox-containing food, and photographed three weeks after injection. In this observation period, six of six injections gave rise to tumors (indicated with asterisks) on mice fed with Dox-impregnated food, while none of the six injections generated tumor on mice fed with regular food.