Abstract
In acute myeloid leukemia (AML) with inv(3)(q21;q26) or t(3;3)(q21;q26), a translocated GATA2 enhancer drives oncogenic expression of EVI1. We generated an
EVI1-GFP AML model and applied an unbiased CRISPR/Cas9 enhancer scan to uncover sequence
motifs essential for EVI1 transcription. Using this approach, we pinpointed a single regulatory element in the translocated GATA2 enhancer that is critically required for aberrant EVI1 expression. This
element contained a DNA-binding motif for the transcription factor MYB, which specifically occupied
this site at the translocated allele and was dispensable for GATA2 expression. MYB knockout as well
as peptidomimetic blockade of CBP/p300-dependent MYB functions resulted in downregulation of
EVI1 but not of GATA2. Targeting MYB or mutating its DNA-binding motif within the GATA2 enhancer
resulted in myeloid differentiation and cell death, suggesting that interference with MYB-driven EVI1
transcription provides a potential entry point for therapy of inv(3)/t(3;3) AMLs.
Significance: We show a novel paradigm in which chromosomal aberrations reveal critical regulatory
elements that are nonfunctional at their endogenous locus. This knowledge provides a rationale to
develop new compounds to selectively interfere with oncogenic enhancer activity.
EVI1-GFP AML model and applied an unbiased CRISPR/Cas9 enhancer scan to uncover sequence
motifs essential for EVI1 transcription. Using this approach, we pinpointed a single regulatory element in the translocated GATA2 enhancer that is critically required for aberrant EVI1 expression. This
element contained a DNA-binding motif for the transcription factor MYB, which specifically occupied
this site at the translocated allele and was dispensable for GATA2 expression. MYB knockout as well
as peptidomimetic blockade of CBP/p300-dependent MYB functions resulted in downregulation of
EVI1 but not of GATA2. Targeting MYB or mutating its DNA-binding motif within the GATA2 enhancer
resulted in myeloid differentiation and cell death, suggesting that interference with MYB-driven EVI1
transcription provides a potential entry point for therapy of inv(3)/t(3;3) AMLs.
Significance: We show a novel paradigm in which chromosomal aberrations reveal critical regulatory
elements that are nonfunctional at their endogenous locus. This knowledge provides a rationale to
develop new compounds to selectively interfere with oncogenic enhancer activity.
| Original language | English |
|---|---|
| Pages (from-to) | 2868-2883 |
| Number of pages | 16 |
| Journal | Cancer Discovery |
| Volume | 11 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - Nov 2021 |
Bibliographical note
Acknowledgments:We thank our colleague Michael Vermeulen and the Bioptics Facility at IMP for flow cytometric sorting. We are thankful to Tobias Neumann for help with the design of the enhancer scanning strategy as well as to the Zuber group at the IMP for their help with the enhancer scanning CRISPR/Cas9 experiments. We thank the Vermeulen group at the Radboud Institute for Molecular Life Sciences for assistance in the DNA-pulldown experiments. Furthermore, we acknowledge Berna Beverloo and the Department of Clinical Genetics for the FISH analysis and colleagues from the bone marrow transplantation group and the molecular diagnostics laboratory of the Department of Hematology for storage of samples and molecular analysis of the leukemia cells. This work was funded by a fellowship from the Daniel den Hoed, Erasmus MC Foundation (to L. Smeenk), the Koningin Wilhelmina Fonds grant from the Dutch Cancer Society (to R. Delwel), the NIH grant R01 DK68634 (to E.H. Bresnick), Carbone Cancer Center P30 CA014520 (to E.H. Bresnick), the NIH T32 HL07899 (to D.R. Matson), and FWF-SFB grant F4710 of the Austrian Science Fund (to J. Zuber). Research at the IMP was generously supported by Boehringer Ingelheim and the Austrian Research Promotion Agency (headquarter grant FFG-852936).
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Footnotes