Figure 1. Presence of an H3K79me2 epigenetic lesion on direct MLL-AF9 fusion targets.
(A) ChIP-Sequencing for H3K79me2 and MLL-AF9 in MLL-AF9 transformed cells. The whole genome view denotes regions associated with H3K79me2 (5507 genes, p=0.02, light green tracks) and Bio-MLL-AF9 (MLL-AF9 direct targets, 139 genes, p=0.0005, dark green tracks). Venn Diagram demonstrating overlap of MLL-AF9 direct targets and genes associated with H3K79me2.
(B) GSEA of the 139 MLL-AF9 direct target genes demonstrating enrichment of gene expression for MLL-AF9 targets in leukemia stem cells (L-GMP) versus normal murine granulocyte macrophage progenitors (GMP) (p<0.001).
(C) H3K79me2 ChIP-Seq signal height and position are shown relative to transcription start site (TSS) for genes grouped according to their expression level in MLL-AF9 L-GMP (No = dark blue to high = red).
(D) Height and distribution of H3K79me2 profiles around the TSS of MLL-AF9 targets (brown) compared to non-targets with similar expression levels (green).
(E) H3K79me2 profiles of selected MLL-AF9 targets and non-targets.
(F) H3K79me2 signal height and position similar to (D) in human MLL-rearranged AML. H3K79me2 ChIP Sequencing was performed on a human MLL-AF9 rearranged primary AML sample. The 139 MLL-AF9 target loci determined in (A) converted to 120 MLL-AF9 target loci in the human genome, defining the MLL-AF9 direct targets (brown). Control gene sets with differential expression levels were created from a previously published expression array data set on human MLL-rearranged AML(Ross et al., 2004) (green).
(G) H3K79me2 profiles relative to the TSS for a list of “core” targets (turquoise) defined as the overlap of the direct MLL-AF9 targets with a previously published gene set of MLL-AF4 direct targets identified in a human MLL-AF4 rearranged cell line.
(H) H3K79me2 profiles relative to the TSS of MLL-fusion target genes expressed in a control AML patient sample with a normal karyotype (no MLL-rearrangement).
(I) H3K79me2 profiles relative to the TSS for “core targets” (defined as in G), in a control AML patient sample with a normal karyotype.