alpha-Difluoromethylornithine induces differentiation of a human embryonal carcinoma cell line in vitro.

Human embryonal carcinoma cells could serve as a useful model system for analysis of early human development. A limited number of human embryonal carcinoma cell lines have been generated from in vivo tumors. We report here that alpha-difluoromethylornithine, a specific enzyme-activated inhibitor of ornithine decarboxylase activity, can induce differentiation in human embryonal carcinoma cells. The differentiated phenotype could be distinguished from undifferentiated cells by altered cellular morphology, biochemical and cell surface antigenic properties. These results suggest that alterations in the intracellular levels of polyamines may play a role in human embryonal carcinoma cell differentiation, and possibly human embryogenesis.