NR1H4 and neoplasm: Specifically, secondary, hydrophobic bile acids function as tumor promoters for a variety of gastrointestinal cancers (27–29, 34) through a combination of mechanisms, including induction of direct oxidative stress with concomitant DNA damage, proliferation, apoptosis, epigenetic gene regulation, altered expression of bile acid receptors, and dysbiosis of the gut microbiota.