Role of the bile acid receptor TGR5 (Gpbar-1) in gastrointestinal tumors

Background: The G-protein coupled bile acid receptor TGR5 (GPBAR1) is expressed in biliary epithelial cells of the liver as well as epithelial cell of the intestine. Receptor activation induces proliferation and anti-apoptotic effects in liver but in the intestine its function is relatively unclear. It was shown that secondary bile acids (BA) are involved in the development of different gastrointestinal (GI) malignant tumors of the intestine and liver. High TGR5 expression levels were detected in cell lines generated from adenocarcinomas of the esophagus and cholangiocarcinoma (CCA). Interestingly, high concentr…