Figure 6. Gene expression signatures of Sox4 and K/L LICs are distinct from MLL-AF9 and MOZ-TIF2 L-GMPs.

(A) Hierarchical clustering of fraction II population from leukemic K/L and Sox4 recipients and their wild-type counterparts; L-GMP population from leukemic MLL-AF9 and MOZ-TIF2 recipients; and HSCs from Cebpa KO mice (KO 21D).

(B) Pair wise correlations between CEBPA and SOX4 in gene expression profiles of human AML patients. The bar and histograms next to each sample indicate: CEBPA allele status (mutations are shown in red and wild-type are shown in green), CEBPA and SOX4 mRNA expression levels. The black lines designate cluster 4 AML patients that have either mutated or silent CEBPA allele(s).

(C) Heatmap shows the 80-gene self-renewal associated LIC signature that are specifically up-regulated in the wild-type HSCs (vs. committed progenitors) as well as Sox4 and K/L LICs (vs. WT FrII) (fold change cutoff=1.5; p value cutoff=0.05).

(D) The Venn diagram shows the overlap between the “self-renewal associated LIC signature” (80 genes) and the “self-renewal associated L-GMP signature” (420 genes) in a single 2-class comparison. Shadow area indicates the “unique C/EBPα-Sox4 LIC signature” (56 genes).

(E) Supervised analysis of gene expression profiles from wild-type HSCs, CMPs, GMPs, MEPs as well as those from MLL-AF9 L-GMP, MOZ-TIF2 L-GMP, Sox4 LICs, K/L LICs and their control counterparts identified a set of self-renewal associated genes that show increased expression only in the L-GMPs but not in the LICs (fold change cutoff=1.5; p value cutoff=0.05).

(F) GSEA demonstrated significant enrichment of the murine “unique C/EBPα-Sox4 LIC signature” in human AML with mutated CEBP (left panel, p=0.005) or with silent CEBP (right panel, p<0.001) as compared to other human AML with wild-type CEBP.

See also Figure S6 and Table S2~S5.