We next analyzed the expression levels of Rab1A in these gastrointestinal cancers (Fig. 1B), and detected significantly higher levels in cholangiocarcinoma (CHOL) and pancreatic adenocarcinoma (PAAD) (P < 0.05), moderately higher levels in stomach adenocarcinoma (STAD), colon adenocarcinoma (COAD), rectum adenocarcinoma (READ) and liver hepatocellular carcinoma (LIHC), and similar levels in the esophageal carcinoma (ESCA) tumor tissues compared to their respective paired normal tissues. Here, RAB1A is linked to cholangiocarcinoma.