PCDH1 and cholangiocarcinoma: The results display high PCDH1 expression was identify in PAAD and other cancers, including bladder urothelial carcinoma (BLCA), breast invasive carcinoma (BRCA), cholangiocarcinoma (CHOL), kidney chromophobe (KICH), liver hepatocellular carcinoma (LIHC), pheochromocytoma, paraganglioma (PCPG), prostate adenocarcinoma (PRAD), and thyroid carcinoma (THCA) (Additional File 1: Fig. S1 and Fig. 1b).