CDH17 (Cadherin 17) is a cadherin-like glycoprotein that is a component of the gastrointestinal tract and pancreatic ducts. It functions as an intestinal proton-dependent peptide transporter in the first step in oral absorption of numerous medically important peptide-based drugs. The protein also participates in the morphological organization of liver and intestine. In gastric cancer, CDH17 expression is correlated with severity and it is thought to play an oncogenic role in promoting proliferation and metastasis. In immunohistochemistry, CDH17 has distinct membranous and cytoplasmic positivity in gastrointestinal tissue and is also found in the appendix. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804; World J Gastroenterol. 2015 Mar 28; 21(12): 3694–3705, PMID: 25834338