CCK and cancer: SLCO1B3 encodes the organic anion transporting polypeptide 1B3 (OATP1B3), which is abundantly expressed in the perivenous section of the liver and mediates the hepatic uptake of endogenous compounds (such as bile acids, dehydroepiandrosterone-3-sulfate, peptide hormones such as cholecystokinin-8 (CCK-8)) and drugs such as lipid-lowering statins (rosuvastatin or atorvastatin) and anti-cancer agents (irinotecan or methotrexate), thereby influencing hepatobiliary elimination34–36.