Coordinated repression of BIM and PUMA by Epstein-Barr virus latent genes maintains the survival of Burkitt lymphoma cells

Cell Death Differ. 2018 Feb;25(2):241-254. doi: 10.1038/cdd.2017.150. Epub 2017 Sep 29.

Abstract

While the association of Epstein-Barr virus (EBV) with Burkitt lymphoma (BL) has long been recognised, the precise role of the virus in BL pathogenesis is not fully resolved. EBV can be lost spontaneously from some BL cell lines, and these EBV-loss lymphoma cells reportedly have a survival disadvantage. Here we have generated an extensive panel of EBV-loss clones from multiple BL backgrounds and examined their phenotype comparing them to their isogenic EBV-positive counterparts. We report that, while loss of EBV from BL cells is rare, it is consistently associated with an enhanced predisposition to undergo apoptosis and reduced tumorigenicity in vivo. Importantly, reinfection of EBV-loss clones with EBV, but surprisingly not transduction with individual BL-associated latent viral genes, restored protection from apoptosis. Expression profiling and functional analysis of apoptosis-related proteins and transcripts in BL cells revealed that EBV inhibits the upregulation of the proapoptotic BH3-only proteins, BIM and PUMA. We conclude that latent EBV genes cooperatively enhance the survival of BL cells by suppression of the intrinsic apoptosis pathway signalling via inhibition of the potent apoptosis initiators, BIM and PUMA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Apoptosis Regulatory Proteins / antagonists & inhibitors
  • Apoptosis Regulatory Proteins / metabolism*
  • Bcl-2-Like Protein 11 / antagonists & inhibitors
  • Bcl-2-Like Protein 11 / metabolism*
  • Burkitt Lymphoma / metabolism*
  • Burkitt Lymphoma / pathology
  • Cell Line
  • Herpesvirus 4, Human / genetics
  • Herpesvirus 4, Human / growth & development
  • Herpesvirus 4, Human / metabolism*
  • Humans
  • Proto-Oncogene Proteins / antagonists & inhibitors
  • Proto-Oncogene Proteins / metabolism*

Substances

  • Apoptosis Regulatory Proteins
  • BBC3 protein, human
  • Bcl-2-Like Protein 11
  • Proto-Oncogene Proteins