A pharmacodynamic assay to monitor treatment with the hypomethylating cytosine analogs, decitabine and azacitidine

Methods Cell Biol. 2024:186:131-150. doi: 10.1016/bs.mcb.2024.02.016. Epub 2024 Mar 21.

Abstract

Hypomethylating therapies using decitabine or azacitidine are actively investigated to treat acute myeloid leukemia, myelodysplastic syndromes, as maintenance therapy after allogenic stem cell transplant and hemoglobinopathies. The therapeutic mechanism is to de-repress genes that have been turned off through oncogenesis or development via methylation. The therapy can be non-cytotoxic at low dosage, sparing healthy stem cells and operating on committed precursors. Because the methods of determining maximum tolerated dose are not well suited to this paradigm, and because the mechanism of action, which is depletion of DNA methylase 1 (DNMT1), is complex and dependent on passing through a cell cycle, a pharmacodynamic assay that measures DNMT1 can inform clinical trials aimed at establishing and improving therapy. Herein, we provide an assay that measures DNMT1 relative levels in circulating T cells of peripheral blood.

Keywords: Acute myeloid leukemia; Beta thalassemia; Cell cycle; Cytometry; DNMT1; Hypomethylating therapy; Myelodysplasia; Sickle cell disease.

MeSH terms

  • Antimetabolites, Antineoplastic / pharmacology
  • Antimetabolites, Antineoplastic / therapeutic use
  • Azacitidine* / pharmacology
  • DNA (Cytosine-5-)-Methyltransferase 1* / genetics
  • DNA (Cytosine-5-)-Methyltransferase 1* / metabolism
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA (Cytosine-5-)-Methyltransferases / metabolism
  • DNA Methylation* / drug effects
  • Decitabine* / pharmacology
  • Humans
  • Myelodysplastic Syndromes / drug therapy
  • Myelodysplastic Syndromes / metabolism
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / metabolism

Substances

  • Azacitidine
  • Decitabine
  • DNA (Cytosine-5-)-Methyltransferase 1
  • Antimetabolites, Antineoplastic
  • DNMT1 protein, human
  • DNA (Cytosine-5-)-Methyltransferases