POSSIBLE NATURALLY OCCURRING TUMOR PROMOTER, TELEOCIDIN-B FROM STREPTOMYCES

Dihydroteleocidin B, a derivative of teleocidin B, when painted on mouse skin, caused marked induction of ornithine decarboxylase within 4 hrs. This induction of ornithine decarboxylase was inhibited by painting the skin with 13-cis-retinoic acid one hour before dihydroteleocidin B. Dihydroteleocidin B induced cell adhesion of human promyelocytic leukemia cells (HL-60) to the surface of culture flasks, and inhibited terminal differentiation of Friend erythroleukemia cells induced by dimethyl sulfoxide. Its effective dose for these actions was comparable to that of the potent tumor promoter, 12-O-tetradecanoyl-phorbol-13-acetate. Teleocidin B seems to be a new type of promoter of carcinogenesis. © 1979.