CDH17 and cholangiocarcinoma: Overexpression of CDH17 is widely reported in various GI cancers, including CRC [7, 8], gastric cancer [9, 10, 11], cholangiocarcinoma [12], hepatocellular carcinoma [13, 14, 15, 16], pancreatic cancer [17], neuroendocrine cancer [18], and esophageal cancer [19].