Tissue culture model of transitional cell carcinoma: characterization of twenty-two human urothelial cell lines

Twenty-two continuous cell lines derived from normal and neoplastic urothelium, maintained under identical culture conditions, were characterized in terms of isozyme phenotype, tumorigenicity, and xenograft morphology following xenotransplantation to nude mice, cytological appearance, in vitro growth rate, labelling index, and colony-forming efficiency, in parallel with separate studies of in vitro drug sensitivities and monoclonal antibody reactivities. Three groups were identified: (a) distinct lines with differing isozyme patterns, a broad spectrum of growth characteristics, and xenograft morphologies similar to the histopathology of the parent tumors after periods of up to 17 yr following establishment in vitro; (b) cross-contaminated sublines (maintained separately in different laboratories for periods of up to 10 yr), with identical isozyme patterns and similar growth characteristics, but differing markedly in tumorigenicity and xenograft morphology; and (c) lines derived from normal urothelium which were nontumorigenic and had an isozyme pattern usually only encountered in untransformed cells. These data indicate that cell lines representative of human transitional cell carcinomas can be selected on the basis of xenograft morphology and isozyme patterns, and that a panel of lines derived from normal and neoplastic urothelium could provide a model system to study the biology and treatment of this disease.