Impairing MLL-fusion gene-mediated transformation by dissecting critical interactions with the lens epithelium-derived growth factor (LEDGF/p75)

Leukemia. 2013 Jun;27(6):1245-53. doi: 10.1038/leu.2013.10. Epub 2013 Jan 15.


The lens epithelium-derived growth factor (LEDGF/p75) tethers the mixed-lineage leukemia (MLL1) protein complex to chromatin. Likewise, LEDGF/p75 tethers the HIV-1 pre-integration complex to chromatin. We previously demonstrated that expression of the C-terminal fragment fused to enhanced green fluorescent protein (eGFP) (eGFP-LEDGF(325-530)) impaired HIV-1 replication. Here, we explored this strategy to selectively interfere with the leukemogenic activity of MLL-fusion proteins. We found that expression of LEDGF(325-530) impaired the clonogenic growth of MLL-fusion gene transformed human and mouse hematopoietic cells, without affecting the growth of control cells immortalized by the FLT3-ITD mutant or normal lineage-marker-depleted murine bone marrow cells. Expression of LEDGF(325-530) was associated with downregulation of the MLL target Hoxa9 and impaired cell cycle progression. Structure-function analysis revealed two small eGFP-fused LEDGF/p75 peptides, LEDGF(424-435) and LEDGF(375-386) phenocopying these effects. Both LEDGF(325-530) and the smaller active peptides were able to disrupt the LEDGF/p75-MLL interaction. Expression of LEDGF(325-530) or LEDGF(375-386) fragments increased the latency period to disease development in vivo in a mouse bone marrow transplant model of MLL-AF9-induced AML. We conclude that small peptides disrupting the LEDGF/p75-MLL interface have selective anti-leukemic activity providing a direct rationale for the design of small molecule inhibitors targeting this interaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Transformation, Neoplastic
  • Histone-Lysine N-Methyltransferase / genetics*
  • Histone-Lysine N-Methyltransferase / metabolism
  • Intercellular Signaling Peptides and Proteins / metabolism*
  • Leukemia, Experimental / genetics
  • Mice
  • Myeloid-Lymphoid Leukemia Protein / genetics*
  • Myeloid-Lymphoid Leukemia Protein / metabolism
  • Protein Binding
  • Recombinant Fusion Proteins / genetics*
  • Recombinant Fusion Proteins / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction


  • Intercellular Signaling Peptides and Proteins
  • Recombinant Fusion Proteins
  • lens epithelium-derived growth factor
  • Myeloid-Lymphoid Leukemia Protein
  • Histone-Lysine N-Methyltransferase
  • Kmt2a protein, mouse