This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by O'Brien, T. G. Articles by Diamond, L. Search for Related Content PubMed PubMed Citation Articles by O'Brien, T. G. Articles by Diamond, L.

Ornithine Decarboxylase Activity and DNA Synthesis after Treatment of Cells in Culture with 12-O-Tetradecanoylphorbol-13-acetate¹

Wistar Institute of Anatomy and Biology, Philadelphia, Pennsylvania 19104

The ability of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) to induce the enzyme ornithine decarboxylase (ODC) and to stimulate DNA synthesis was studied in four different cell types in vitro. The effects of this agent on each cell type were different: (a) in hamster embryo cells, TPA induced ODC but had no effect on DNA synthesis; (b) TPA induced ODC and stimulated DNA synthesis in BALB/c 3T3 mouse cells; (c) it did not induce ODC in human fibroblasts but did stimulate DNA synthesis; and (d) it induced neither ODC nor DNA synthesis in rat embryo fibroblasts. In contrast to the effects of TPA, ODC was induced and DNA synthesis was stimulated in all cell types by fresh serum-containing medium. Treatment of the cells with a combination of fresh medium and TPA resulted in an approximate summation of the effects of treatment with each agent alone.

These results emphasize the differences in the responses of various cells to TPA. They also show that in some cells, at least, the induction of ODC and stimulation of DNA synthesis following TPA treatment can be regulated independently.

¹ This research was supported in part by grants from the National Cancer Institute CA 08936, CA 05545, CA 09171, and CA 21778 and the National Institute for Environmental Health Sciences ES 01664.

² To whom requests for reprints should be addressed.

Received 5/ 3/79. Accepted 8/ 9/79.