Single-cell molecular analysis defines therapy response and immunophenotype of stem cell subpopulations in CML

Research output: Contribution to journalArticle

Abstract

Understanding leukemia heterogeneity is critical for the development of curative treatments as the failure to eliminate therapy-persistent leukemic stem cells (LSCs) may result in disease relapse. Here we have combined high-throughput immunophenotypic screens with large-scale single-cell gene expression analysis to define the heterogeneity within the LSC-population in chronic phase chronic myeloid leukemia (CML) patients at diagnosis and following conventional tyrosine kinase inhibitor (TKI) treatment. Our results reveal substantial heterogeneity within the putative LSC population in CML at diagnosis and demonstrate differences in response to subsequent TKI-treatment between distinct subpopulations. Importantly, LSC subpopulations with myeloid and proliferative molecular signatures are proportionally reduced at a higher extent in response to TKI-therapy compared to subfractions displaying primitive and quiescent signatures. Additionally, cell surface expression of the CML stem cell markers CD25, CD26, and IL1RAP is high on all subpopulations at diagnosis, but downregulated and unevenly distributed across subpopulations in response to TKI-treatment. The most TKI-insensitive cells of the LSC-compartment can be captured within the CD45RA- fraction and further defined as positive for CD26 in combination with an aberrant lack of cKIT expression. Together, our results expose a considerable heterogeneity of the CML stem cell population and propose a Lin(-)CD34(+)CD38(-/low)CD45RA(-)cKIT(-)CD26(+) population as potential therapeutic target for improved therapy response.

Details

Authors
Organisations
External organisations
  • Karolinska Institutet
  • Aarhus University Hospital
  • Uppsala University Hospital
  • St. Olav’s University Hospital
  • University of Helsinki
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Hematology
Original languageEnglish
Pages (from-to)2384-2394
JournalBlood
Volume129
Issue number17
Early online date2017 Jan 25
Publication statusPublished - 2017 Apr
Publication categoryResearch
Peer-reviewedYes