Fatty Acid-Binding Protein 6 (FABP6) is cytoplasmic protein that binds long-chain fatty acids and other hydrophobic ligands which belongs to the calycin superfamily. FABP6 expression is restricted in the small intestine to the ileum where it is involved in the enterohepatic circulation of bile acids. FABP6 forms a beta-barrel structure that accommodates the hydrophobic ligand in its interior. Isoform 2 is expressed in colorectal adenocarcinomas and their adjacent normal mucosa (at protein level). Isoform 1 is expressed in the jejunum, ileum, cecum and ascending colon intestine. FABP6 plays a role in fatty acid uptake, transport, and metabolism. FABP6 stimulates gastric acid and pepsinogen secretion. It seems to be able to bind to bile salts and bilirubins.