the liver to facilitate digestion of dietary fats. High exposure of the gastrointestinal tract to bile acids can occur in several different settings, but most significantly is prevalent among individuals who have a high dietary fat intake. High bile acid exposure has been implicated in several cancers of both the upper and lower digestive tract. The deleterious effects on cells of elevated bile acid exposure include induction of reactive oxygen species, induction of DNA damage leading to mutation, and induction of apoptosis in the short term and selection for apoptosis resistance over the long term. References External links Gastrointestinal (GI) Cancer Resource Centre Gastrointestinal Cancer Treatment