Induction of granulocyte-macrophage colony-stimulating activity by 12-O-tetradecanoylphorbol-13-acetate in SENCAR and B6C3F1 mice.

Abstract

Previous studies in this laboratory and others have indicated that 12-O-tetradecanoylphorbol-13-acetate (TPA), the most potent skin tumor promoter known, evokes significantly greater inflammatory responses in phorbol ester-sensitive (SENCAR) mice compared to strains (e.g. C57BL/6 and B6C3F1) that are relatively resistant to the outgrowth of skin tumors in two-stage chemically induced carcinogenesis protocols. In the studies reported herein, subchronic topical application of TPA at doses relevant to two-stage protocols induced serum granulocyte-macrophage colony-stimulating activity (GM-CSA) in both SENCAR and B6C3F1 mice; however, the increase in SENCAR mice was significantly greater than that observed in the relatively resistant B6C3F1 strain (5-fold versus a 2-fold increase respectively). The greater increase in serum GM-CSA observed in SENCAR mice was correlated with a 31% increase in the number of splenic leukocytes that lacked both B and T cell surface markers (i.e. double-negative cells), a presumed GM progenitor cell; no significant increase in the relative percentage of such cells was observed in B6C3F1 mice. Alternatively, significant decreases in splenic T lymphocytes (23 and 32% in SENCAR and B6C3F1 respectively) were observed in both strains of TPA-treated mice and may, in part, account for the previously observed decreases in splenic cell blastogenic response to the T cell mitogen phytohemagglutinin (PHA). In vitro incubation of splenic cells from SENCAR mice with 0.01-1.0 microM TPA led to significantly greater increases in colony formation relative to splenic cells isolated from B6C3F1 mice; therefore, differences in the biochemical responsiveness between strains may occur at the level of signal transduction in splenic GM progenitor cells. In conclusion, these studies indicated that strain-dependent differences in the systemic inflammatory response following topical application of TPA may result from direct stimulation of splenic GM precursor cells by TPA and/or may occur, indirectly, through the release of cytokines [e.g. GM colony-stimulating factor (GM-CSF)] by induced epidermal (or other) cells.

• Authors: L W Updyke, H L Yoon, R W Pfeifer
• Journal: Carcinogenesis (Carcinogenesis) Vol. 12 Issue 4 Pg. 735-9 (Apr 1991) ISSN: 0143-3334 [Print] England
• PMID: 2013137 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, Surface
• Granulocyte-Macrophage Colony-Stimulating Factor
• Tetradecanoylphorbol Acetate

Topics

• Administration, Topical
• Animals
• Antigens, Surface (analysis)
• Bone Marrow (drug effects)
• Bone Marrow Cells
• Cell Count (drug effects)
• Female
• Flow Cytometry
• Granulocyte-Macrophage Colony-Stimulating Factor (biosynthesis, blood)
• Mice
• Mice, Inbred Strains (physiology)
• Skin (drug effects, metabolism)
• Spleen (cytology, drug effects)
• Tetradecanoylphorbol Acetate (administration & dosage, pharmacology)