TBK1 and cholangiocarcinoma: Our results showed that TBK1 expression was higher in the bile ducts with CCA and lower in the adjacent bile ducts with tumour invasion, and no TBK1 expression was detected in adjacent nontumor tissues (including the left hepatic duct, interlobular bile duct, and capillary bile duct) (Fig. 1G and Supplementary Fig. 1E).