Hepatic leukemia factor is a novel leukemic stem cell regulator in DNMT3A, NPM1, and FLT3-ITD triple-mutated AML

Blood. 2019 Jul 18;134(3):263-276. doi: 10.1182/blood.2018862383. Epub 2019 May 10.

Abstract

FLT3, DNMT3A, and NPM1 are the most frequently mutated genes in cytogenetically normal acute myeloid leukemia (AML), but little is known about how these mutations synergize upon cooccurrence. Here we show that triple-mutated AML is characterized by high leukemia stem cell (LSC) frequency, an aberrant leukemia-specific GPR56 highCD34low immunophenotype, and synergistic upregulation of Hepatic Leukemia Factor (HLF). Cell sorting based on the LSC marker GPR56 allowed isolation of triple-mutated from DNMT3A/NPM1 double-mutated subclones. Moreover, in DNMT3A R882-mutated patients, CpG hypomethylation at the HLF transcription start site correlated with high HLF mRNA expression, which was itself associated with poor survival. Loss of HLF via CRISPR/Cas9 significantly reduced the CD34+GPR56+ LSC compartment of primary human triple-mutated AML cells in serial xenotransplantation assays. HLF knockout cells were more actively cycling when freshly harvested from mice, but rapidly exhausted when reintroduced in culture. RNA sequencing of primary human triple-mutated AML cells after shRNA-mediated HLF knockdown revealed the NOTCH target Hairy and Enhancer of Split 1 (HES1) and the cyclin-dependent kinase inhibitor CDKN1C/p57 as novel targets of HLF, potentially mediating these effects. Overall, our data establish HLF as a novel LSC regulator in this genetically defined high-risk AML subgroup.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic-Leucine Zipper Transcription Factors / metabolism*
  • Biomarkers
  • Cell Cycle / genetics
  • Cell Line, Tumor
  • Computational Biology / methods
  • DNA (Cytosine-5-)-Methyltransferases / genetics*
  • Disease Models, Animal
  • Gene Duplication
  • Gene Expression Profiling
  • Humans
  • Immunophenotyping
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / metabolism*
  • Mice, Transgenic
  • Mutation
  • Neoplastic Stem Cells / metabolism*
  • Nuclear Proteins / genetics*
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism
  • Tandem Repeat Sequences
  • Transcription Initiation Site
  • Transcriptome
  • fms-Like Tyrosine Kinase 3 / genetics*

Substances

  • ADGRG1 protein, human
  • Basic-Leucine Zipper Transcription Factors
  • Biomarkers
  • HLF protein, human
  • Nuclear Proteins
  • Receptors, G-Protein-Coupled
  • nucleophosmin
  • DNA (Cytosine-5-)-Methyltransferases
  • DNA methyltransferase 3A
  • FLT3 protein, human
  • fms-Like Tyrosine Kinase 3