TNN and intrahepatic cholangiocarcinoma: These results suggest that a secreted factor in the tumor microenvironment, mimicked by co-cultures of Huh-28 and 196hT cells in vitro, is required for the production and assembly of tenascin-W-positive fibrils in the tumor stroma, and that the cancer cells themselves can be/are the source of tenascin-W, at least in ICC.