A pan‐cancer analysis of the TCGA database showed that PES1 is highly expressed in various types of cancer, such as bladder urothelial carcinoma (BLCA), HNSCC, cholangiocarcinoma (CHOL), lung adenocarcinoma (LUAD), oesophageal carcinoma (ESCA), breast invasive carcinoma (BRCA), kidney renal clear cell carcinoma (KIRC) and colon cancer (COAD), etc. (Figure 1A). This evidence concerns the gene PES1 and cholangiocarcinoma.