KCNN2 was found to be involved in the bile secretion, and the abnormal expression of KCNN2 may be closely related to the pathogenesis of cholangiocarcinoma.25 In addition, KCNN2 was also found under‐expressed in Ewing's sarcoma family of tumours relative to alveolar rhabdomyosarcomas, and may be also involved in prostate carcinomas26; Keratin 80, also known as KRT80,27 whose gene is located at the centromeric end of the type II keratin gene domain, are filament proteins that constitutes one of the main structural fibres of epithelial cells. This evidence concerns the gene KCNN2 and cholangiocarcinoma.