Intracellular Cholesterol Pools Regulate Oncogenic Signaling and Epigenetic Circuitries in Early T-cell Precursor Acute Lymphoblastic Leukemia

Cancer Discov. 2022 Mar 1;12(3):856-871. doi: 10.1158/2159-8290.CD-21-0551.

Abstract

Early T-cell acute lymphoblastic leukemia (ETP-ALL) is an aggressive hematologic malignancy associated with early relapse and poor prognosis that is genetically, immunophenotypically, and transcriptionally distinct from more mature T-cell acute lymphoblastic leukemia (T-ALL) tumors. Here, we leveraged global metabolomic and transcriptomic profiling of primary ETP- and T-ALL leukemia samples to identify specific metabolic circuitries differentially active in this high-risk leukemia group. ETP-ALLs showed increased biosynthesis of phospholipids and sphingolipids and were specifically sensitive to inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase, the rate-limiting enzyme in the mevalonate pathway. Mechanistically, inhibition of cholesterol synthesis inhibited oncogenic AKT1 signaling and suppressed MYC expression via loss of chromatin accessibility at a leukemia stem cell-specific long-range MYC enhancer. In all, these results identify the mevalonate pathway as a druggable novel vulnerability in high-risk ETP-ALL cells and uncover an unanticipated critical role for cholesterol biosynthesis in signal transduction and epigenetic circuitries driving leukemia cell growth and survival.

Significance: Overtly distinct cell metabolic pathways operate in ETP- and T-ALL pointing to specific metabolic vulnerabilities. Inhibition of mevalonate biosynthesis selectively blocks oncogenic AKT-MYC signaling in ETP-ALL and suppresses leukemia cell growth. Ultimately, these results will inform the development of novel tailored and more effective treatments for patients with high-risk ETP-ALL. This article is highlighted in the In This Issue feature, p. 587.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carcinogenesis / metabolism
  • Cholesterol / metabolism
  • Epigenesis, Genetic
  • Humans
  • Mevalonic Acid / metabolism
  • Precursor Cells, T-Lymphoid* / metabolism
  • Precursor Cells, T-Lymphoid* / pathology
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma* / pathology
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism
  • Signal Transduction

Substances

  • Proto-Oncogene Proteins c-myc
  • Cholesterol
  • Mevalonic Acid