AML cells accumulate iron. (A) FACS analysis of the mean fluorescence intensity (MFI) of surface CD71 in nonmalignant Ter119⁺ erythroid precursors and AML blasts in the BM. n = 5 mice per group. (B) Analysis of CD71 MFI in all or in proliferating Ki-67^hi control nonmalignant BM cells and AML blasts isolated from the BM. n = 5 mice per group. (C) Representative TEM images of BM cells from control and leukemic mice and EDS quantification of atomic iron (Fe) in selected cells. n = 7-9 cells from 3 mice per group. (D) FACS quantification of the labile iron pool (LIP) in BM mononuclear cells (BMMC) or CD11b⁺ cells from control mice or leukemic cells from AML-burdened mice. The fluorescent indicator Phen Green SK is quenched by iron (lower Phen Green SK MFI corresponds to higher LPI). Each dot represents a mouse. Expression of heme oxygenase 1 (Hmox1), (E) ferritin light chain 1 (Ftl1), and ratio between ferritin heavy chain 1 (Fth1) and Ftl1 expression in nonmalignant GMPs and AML cells (GSE105159). Each dot represents a mouse. (F) Flow cytometry analysis of ferroportin (FPN) in nonmalignant monocytes and AML cells. Right, representative histogram. Each dot represents a mouse.