CHARACTERIZATION OF HUMAN TUMOR-CELL LINES USING ANTIBODIES TO INTERMEDIATE FILAMENTS

The human hepatoma cell line G2 (Hep G2) has been compared to lung car cinoma, sarcoma and skin fibroblasts for the expression of intermediat e filaments, i.e. vimentin and cytokeratin. The immunofluorescence stu dy revealed that, in contradiction to Szecheng et al. (1987), cytokera tin and vimentin are absent in Hep G2. Human skin fibroblasts and sarc oma cells expressed vimentin as expected for their mesenchymal origin, but a positive reaction to vimentin could also be shown in lung carci noma cells. However, the vimentin filament structure of both these tum our cell lines was different in comparison with skin fibroblasts. Ther efore determining the exact tissue origin of tumour cell lines by mean s of intermediate filament characterization remains doubtful.