Lipoxygenase metabolism is required for interleukin-3 dependent proliferation and cell cycle progression of the human M-07e cell line
✍ Scribed by Alan M. Miller; Beverly Steele Allen; Vincent Ziboh
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 184 KB
- Volume
- 170
- Category
- Article
- ISSN
- 0021-9541
No coin nor oath required. For personal study only.
✦ Synopsis
The cell line M-07e requires either Interleukin-3 (IL-3) or granulocyte-macrophage colony stimulating factor (GM-CSF) for proliferation in vitro. Cells deprived of growth factor for up to 48 hours remain viable but no longer divide. The growthfactor-deprived M-07e cells begin to divide within 48 hours of reexposure to IL-3. Flow cytometric analysis of M-07e cells labeled with hypotonic propidium iodide demonstrates that the percentage of cells undergoing DNA synthesis decreases from 24%, in a log phase population of IL-3 stimulated cells, to 1% when cells are deprived of IL-3 for 24 hours. IL-3-deprived cells accumulate predominantly in a flow cytometry peak representative of G 0 /G 1 . DNA synthetic activity, as determined by tritiated thymidine uptake and flow cytometry, resumes between 12 and 18 hours after reexposure to IL-3, reaching a peak of up to 40% by 24 hours and returning to log phase levels by 72 hours. Prior to initiation of DNA synthesis, increases are seen in mRNA levels for five-lipoxygenase-activating protein (FLAP). Following reexposure to IL-3, a rapid time-dependent biosynthesis of leukotriene D4 (LTD4) is induced by M-07e cells. When IL-3 is added in the presence of any of three lipoxygenase inhibitors tested (Piriprost, caffeic acid, nordihydroguiaretic acid) or FLAP inhibitor, MK-886, there is dose-dependent inhibition of the resumption of proliferation and of DNA synthesis. Flow cytometric cell cycle analysis demonstrates that the inhibited cells remain in the G 0 /G 1 population and do not progress through the cell cycle. These results are consistent with our previous observation that an intact lipoxygenase pathway is necessary for hematopoietic growth-factor-stimulated colony formation of normal bone marrow myeloid progenitors and suggest that the induction of a lipoxygenase metabolite or metabolites is necessary for myeloid cells to progress through the cell cycle when stimulated by a hematopoietic growth factor.