Elevated CD133 expression was observed in several cancers in the TCGA dataset, including colon adenocarcinoma (COAD), cholangiocarcinoma (CHOL), pancreatic adenocarcinoma (PAAD), rectum adenocarcinoma (READ), and stomach adenocarcinoma (STAD) (Fig. 1A). This evidence concerns the gene PROM1 and cholangiocarcinoma.