Non-phorbol mouse skin tumor promoters do not mimic phorbol myristate acetate in its effects on chick embryo fibroblasts
✍ Scribed by Paul E. Driedger; Peter M. Blumberg
- Book ID
- 102867971
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- French
- Weight
- 575 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0020-7136
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✦ Synopsis
Abstract
Phorbol esters, the most potent class of tumor promoter for mouse skin, have been shown to cause loss of the large external transformation‐sensitive glycoprotein LETS^1^ from the surface of chicken embryo fibroblasts (CEF) and to cause an increase in the rate of deoxyglucose (DG) transport by these cells. Several compounds which promote mouse skin tumors but which are structurally unrelated to the phorbol esters were tested for their abilities to cause loss of LETS from CEF and to stimulate DG transport. Of the seven compounds tested, only oleic acid (at 140 μM) caused a decrease of more than 20% in LETS, as measured by lactoperoxidase‐catalyzed surface radioiodination. Phenol at 1 mM caused a 70% increase in LETS levels. Only three agents, anthralin, lauric acid and limonene, caused increases in DG transport. Iodo‐acetic acid and canthridin were inactive in both assays. None of the compounds affected CEF LETS levels or DG transport to the extent that the phorbol esters do. Palmitic and stearic acids, which are structurally similar to oleic acid but which do not promote mouse skin tumors, were inactive in both assays. The lack of correspondence between the effects on CEF of the phorbol esters and the non‐phorbol promoters suggests that these two groups may have different mechanisms of action.