Neoplastic transformation in vitro of a clone of adult liver epithelial cells into differentiated hepatoma-like cells under conditions of nutritional stress.

Differentiated epithelial cells in contact-inhibited monolayers derived from adult rat liver have been transformed in vitro into epithelioid neoplastic cells under conditions of nutritional stress. The transformed cells maintain their differentiated quality and manufacture serum proteins. They differ from control cultures in the following properties: They are aneuploid, can be agglutinated by wheat-germ agglutinin and concanavalin A, can grow in suspension, and are able to form colonies in semisoft agar. There is no intercellular communication at permeable junctions between the cells; this is demonstrable by electrical measurement or by injection of fluorescein. The cells show invasiveness in culture, and are not inhibited by contact with normal cells. The characteristics of the hepatocytes after transformation in vitro resemble those of epithelioid cells derived from a transplantable hepatoma.