Targeting the HTLV-I-Regulated BATF3/IRF4 Transcriptional Network in Adult T Cell Leukemia/Lymphoma

Cancer Cell. 2018 Aug 13;34(2):286-297.e10. doi: 10.1016/j.ccell.2018.06.014. Epub 2018 Jul 26.

Abstract

Adult T cell leukemia/lymphoma (ATLL) is a frequently incurable disease associated with the human lymphotropic virus type I (HTLV-I). RNAi screening of ATLL lines revealed that their proliferation depends on BATF3 and IRF4, which cooperatively drive ATLL-specific gene expression. HBZ, the only HTLV-I encoded transcription factor that is expressed in all ATLL cases, binds to an ATLL-specific BATF3 super-enhancer and thereby regulates the expression of BATF3 and its downstream targets, including MYC. Inhibitors of bromodomain-and-extra-terminal-domain (BET) chromatin proteins collapsed the transcriptional network directed by HBZ and BATF3, and were consequently toxic for ATLL cell lines, patient samples, and xenografts. Our study demonstrates that the HTLV-I oncogenic retrovirus exploits a regulatory module that can be attacked therapeutically with BET inhibitors.

Keywords: ATLL; BATF3; BET inhibitor; HBZ; functional genomics.

Publication types

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

MeSH terms

  • Animals
  • Basic-Leucine Zipper Transcription Factors / genetics*
  • Basic-Leucine Zipper Transcription Factors / physiology
  • Cell Line, Tumor
  • Gene Regulatory Networks*
  • Genes, myc
  • Human T-lymphotropic virus 1 / physiology*
  • Humans
  • Interferon Regulatory Factors / genetics*
  • Leukemia-Lymphoma, Adult T-Cell / genetics*
  • Mice
  • Proteins / antagonists & inhibitors
  • Retroviridae Proteins / physiology

Substances

  • BATF protein, human
  • Basic-Leucine Zipper Transcription Factors
  • HBZ protein, human T-cell leukemia virus type I
  • Interferon Regulatory Factors
  • Proteins
  • Retroviridae Proteins
  • bromodomain and extra-terminal domain protein, human
  • interferon regulatory factor-4