GCG and intrahepatic cholangiocarcinoma: Based on our previous studies [11] about the analysis of clinical data of intrahepatic cholangiocarcinoma and immunohistochemical staining, we find that positive expression of GLP-1R is very high in intrahepatic cholangiocarcinoma tissue, indicating that GLP-1 is closely associated to the occurrence and development of cholangiocarcinoma.