KRT19 and neoplasm: To confirm the presence of two distinct differentiation lineages of neoplasm within our experimental cohorts, we stained tissue sections for markers of the biliary epithelium (cytokeratin 19; CK-19) and hepatocytes (hepatocyte-specific antigen 1; Hep Par 1) that have previously been used to distinguish ICC from HCC clinically [54,55,56,57,58,59].