Self-renewal and cancer of the gut: two sides of a coin.Notch/gamma-secretase inhibition turns proliferative cells in intestinal crypts and adenomas into goblet cells.From gut homeostasis to cancer.Notch1 functions as a tumor suppressor in mouse skinLoss of intestinal crypt progenitor cells owing to inactivation of both Notch1 and Notch2 is accompanied by derepression of CDK inhibitors p27Kip1 and p57Kip2.