In our previous studies, we found that Jag1 is a transcriptional target of Yap, the transcriptional co-activator downstream of Hippo tumour suppressor pathway, in multiple tumour types.42 We also showed that Yap is frequently activated in human ICC cells.43 However, our preliminary data seem to exclude that Jag1 is a Yap target in human ICC (Pilo et al. unpublished observation). This evidence concerns the gene JAG1 and intrahepatic cholangiocarcinoma.