Cytokines and hypoxia do not alter C-X-C chemokine receptor 7 (CXCR7) expression in acute myeloid leukemia (AML) cells. (A) AML cell lines were treated with cytokines at various concentrations for up to 72 hr and then subjected to flow cytometric analysis. Representative results (upper panel) and fold-increase of mean fluorescence intensity (MFI) of the experimental cells from that in the controls (no cytokine treatment) (lower panel) from 3 independent experiments, in which U937 cells were treated with 10 µg of each cytokine for 24 hr, are shown. Cells were incubated with 5% CO₂ and 1% O₂, balanced with N₂ gas, at 37℃ for up to 12 hr, and then subjected to flow cytometric analysis (B) and western blot analysis (C).

Abbreviations: IL-6, interleukin 6; GM-SCF, granulocyte-macrophage colony-stimulating factor; TGF-β, tumor growth factor-β; INF-γ, interferon-γ; TNF-α, tumor necrosis factor-α; G-CSF, granulocyte colony-stimulating factor; SCF, stem cell factor; TPO, thrombopoietin; Con, control.