Mutations in the tumor suppressor protein APC inappropriately activate the transcription factor Tcf4, which in turn activates genes that cause intestinal epithelial cells to become transformed into cancer cells. Roose et al. show that the gene encoding another member of this transcription factor family, Tcf1, is a direct target of Tcf4. Tcf1 acts as a feedback repressor of Tcf4 by antagonizing its effects on cell transformation. Thus, Tcf1 cooperates with APC in suppressing tumorigenesis.
Roose, J., Huls, G., van Beest, M., Moerer, P., van der Horn, K., Goldschmeding, R., Logtenberg, T., Clevers, H. (1999) Synergy between tumor suppressor APC and the ?-catenin -Tcf4 target Tcf1. Science 285: 1923-1925. [Abstract] [Full Text]