TUMOR PROMOTERS INHIBIT METABOLIC COOPERATION IN COCULTURES OF EPIDERMAL AND 3T3-CELLS

Cultures of mouse epidermal cells ( HEL 37) were prelabelled by incubation for 2-3 h with 3H-uridine. The cells were washed and cocultured for 4 h with unlabelled 3T3 cells. Communication between 3T3 and HEL 37 cells, as evidenced by the transfer of label from HEL 37 cells to contacting 3T3 cells, was inhibited by inclusion of the tumor promoting agents, 12-0-tetradecanoylphorbol-13-acetate (10-7-10-9 M) and phorbol-12,13-didecanoate (10-7 M) during coculture. Non-promoting derivatives of these phorbol esters did not inhibit transfer of label. © 1979.