Metabolic cooperation between cells from three human hepatoma cell lines was studied by the clonogenic method and by autoradiography. It was found that human HGPRT+/HGPRT- SK-HEP-1 cells only, showed a metabolic cooperation capacity that was inhibited by tumour promoters 12-O-tetradecanoylphorbol-13-acetate (TPA) and phenobarbital, and was not inhibited by the non-promoter 4-O-methyl TPA, provided suitable experimental conditions (short exposure times) were used. This biological system might be the basis of a new in vitro short-term screening test for potential tumour-promoting chemicals.
Carcinogens Carcinoma, Hepatocellular