Targeting Chromatin Regulators Inhibits Leukemogenic Gene Expression in NPM1 Mutant Leukemia

ABSTRACT: Homeobox (HOX) proteins and the receptor tyrosine kinase FLT3 are frequently highly expressed and mutated in acute myeloid leukemia (AML). Aberrant HOX expression is found in nearly all AMLs that harbor a mutation in the Nucleophosmin (NPM1) gene, and FLT3 is concomitantly mutated in approximately 60% of these cases. Little is known how mutant NPM1 (NPM1mut) cells maintain aberrant gene expression. Here, we demonstrate that the histone modifiers MLL1 and DOT1L control HOX and FLT3 expression and differentiation in NPM1mut AML. Using a CRISPR-Cas9 genome editing domain screen, we show NPM1mut AML to be exceptionally dependent on the menin binding site in MLL1. Pharmacological small-molecule inhibition of the menin-MLL protein interaction had profound anti-leukemic activity in human and murine models of NPM1mut AML in vitro and in vivo. Combined pharmacological inhibition of menin-MLL and DOT1L resulted in dramatic suppression of HOX and FLT3 expression, induction of differentiation, and superior activity against NPM1mut leukemia. Together, MLL1 and DOT1L are chromatin regulators that control HOX, MEIS1 and FLT3 expression and are therapeutic targets in NPM1mut AML. Combinatorial small-molecule inhibition has synergistic on target activity and constitutes a novel therapeutic concept for this common AML subtype. RNA sequencing data of the human AML cell lines OCI-AML2 and OCI-AML3 comparing EPZ004777 [10µM] drug treatment versus DMSO vehicle control; experiments performed in biological triplicates.

ORGANISM(S): Homo sapiens

SUBMITTER: Richard Koche 

PROVIDER: E-GEOD-85107 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress