We have investigated the effects of interleukin-4 (IL-4) on the proliferation of chronic myelomonocytic leukemia (CMMoL) cells in the chronic and leukemic transformation phases in vitro. CMMoL cells formed colonies spontaneously in both phases. IL-4 suppressed the spontaneous growth in the chronic phase, but on the other hand, stimulated colony formation in the leukemic transformation phase. Anti-IL-6 antibody inhibited spontaneous colony formation in both phases. CMMoL cells in both phases produced high levels of IL-6, compared with those produced by acute myelogenous leukemia (AML) cells showing myelomonocytic differentiation and normal monocytes. IL-4 suppressed the IL-6 production by CMMoL cells in both phases. None of anti-IL-6, anti-macrophage colony-stimulating factor (M-CSF), anti-granulocyte-macrophage colony-stimulating factor (GM-CSF), anti-tumor necrosis factor-α (TNF-α) and anti-IL-1-β antibodies inhibited IL-4-stimulated colony formation. These results suggest that IL-4 directly stimulates the growth of CMMoL cells once leukemic transformation has occurred and that the therapeutic use of IL-4 for CMMoL should he viewed with caution, especially in the leukemic transformation phase.
|Number of pages
|Published - Jun 1995
All Science Journal Classification (ASJC) codes
- Cancer Research