Serotonin synthesis protects the mouse colonic crypt from DNA damage and colorectal tumorigenesis

Serotonin (5‐HT) signaling pathways are thought to be involved in colorectal tumorigenesis (CRT), but the role of 5‐HT synthesis in the early steps of this process is presently unknown. In this study, we used carcinogen treatment in the tryptophan hydroxylase 1 knockout (Tph1KO) and transgenic (Tph1 fl/fl Villin Cre ) mouse models defective in 5‐HT synthesis to investigate the early mutagenic events associated with CRT. Our observations of the...