Transcriptional profiling of phenotypic hematopoietic stem and progenitor compartments of AML patients with monosomy 7 identifies overexpression of IL1RAP. (A) Schematic showing the cell types used for pairwise comparison of gene expression. Phenotypically defined hematopoietic stem and progenitor compartments with potential LSC activity were sorted and compared between healthy and AML individuals. The symbol “Δ” refers to the gene expression differences between groups in each phenotypically defined compartment: LT-HSCs, ST-HSCs, and GMPs. (B) Hierarchical clustering of the 50 most significantly dysregulated genes in −7 AML in phenotypically defined LT-HSCs, ST-HSCs, and GMPs of AML patients compared with HC. Heat maps of log₂-transformed gene expression levels are shown (top). Position of IL1RAP is indicated. Venn diagram (bottom) shows the number of differentially expressed genes that are shared between, or restricted to, specific compartments between AML samples and HC. The numbers represent the total of up- or down-regulated genes in each pairwise comparison. Genes in the triple intersection (common overlap) are listed. Red and green arrows indicate overexpression and down-regulation in the AML samples, respectively. (C) Validation of IL1RAP mRNA expression in LT-HSCs, ST-HSCs, and GMPs. Yellow bars represent expression levels in the gene expression array (n = 4 for LT-HSCs, n = 5 for ST-HSCs, and n = 6 for GMPs). Blue bars represent mRNA levels determined by quantitative RT-PCR in amplified RNA (n = 2). Red bars represent the mRNA levels measured by quantitative RT-PCR from unamplified cDNA (n = 1 for LT-HSCs and n = 2 for ST-HSCs and GMPs). mRNA levels were normalized to GAPDH. Fold change compared with HC is shown.