TGFB1 and intrahepatic cholangiocarcinoma: Taken together, the results of the present study showed, for the first time, the different levels of β4 and β6 integrin expression in ICC subgroups, and suggested that integrin expression is associated with the subclassification and clinicopathological features of ICC through the coincident expression of laminin-5 and tenascin-C, as well as of TGF-β1.