Figure 2. FoxOs Are Active and Suppress Myeloid Maturation in Murine AML Cells.

(A) Table of activated (left panel) and repressed (right panel) FoxO target genes differentially expressed between GMP and L-GMP microarray datasets (D-Chip analysis, p = 0.95).

(B) Immunofluorescence of purified lineage^low, Sca-1⁻, cKit^high, CD34⁺, FcgRII/III⁺ cells from healthy and MLL-AF9-induced leukemic mice with FoxO3-specific antibodies (75D8) and DAPI contrast.

(C) Mononuclear bone marrow leukemia cells expressing MLL-AF9 and bearing floxed alleles for FoxO1, FoxO3, and FoxO4 (FoxO1/3/4^floxed;MLL-AF9 cells) were infected with Ctrl or CreER-expressing recombinant retroviruses and then treated with vehicle or 400 nM 4-hydroxytamoxifen (4-OHT) for 4–6 hr. 48–72 hr following treatment, cells from all conditions were subjected to western blotting with FoxO3, Tubulin, and Cre antibodies.

(D) Five days following treatment, Ctrl and CreER cells from each condition were assessed by flow cytometry for CD11b and Gr-1 expression (*CreER + 4-OHT versus CreER + vehicle, Ctrl + vehicle, or Ctrl + 4-OHT, p < 0.0001; n = 3, data represented as the mean ± SEM) and (E) stained with May-Grünwald Giemsa.

See also Figure S2.