C/EBPβ expression in mouse HSC and human AML patients. (A) Expression of C/EBPβ and Evi1 in the BM of normal mice. The expression level of KSL is set to 1. KSL indicates c-Kit–positive, Sca1-positive and lineage-negative cells; CMP, common myeloid progenitor cells; MEP, megakaryocyte erythroid progenitor cells; and GMP, granulocyte/macrophage progenitor cells. Expression levels were normalized by the expression level of 18S rRNA. (B-C) Total cell lysates of the human whole BM cells, CD34⁺ cells, and CD34⁻ cells were immunoblotted with anti-C/EBPβ Ab (top panel, Santa Cruz, C-19), anti-Evi1 Ab (second panel, Cell Signaling), anti-C/EBPα Ab (third panel, Santa Cruz, 14AA), and anti-β actin (bottom panel, Cell Signaling). CD34^+/− cells of control sample ID 6 are derived from the residual PB stem cells for autologous transplantation. CD34^+/− cells of control sample ID 10 and 11 are derived from BM. (D) The intensities of the bands of LAP*, LIP, Evi1, and β-actin in AML samples were quantitated by densitometry using Multi Gauge Version 3.0 software (Fujifilm). The intensities of the bands of LAP*, LIP, and Evi1 were normalized by the intensities of the bands of β-actin (n = 10). Spearman rank correlation coefficient of Evi1 and LAP* = 0.744; P = .0032. Spearman rank correlation coefficient of Evi1 and LIP = 0.679; P = .0128.