Bmi-1 is induced by the Epstein-Barr virus oncogene LMP1 and regulates the expression of viral target genes in Hodgkin lymphoma cells

Blood. 2007 Mar 15;109(6):2597-603. doi: 10.1182/blood-2006-05-020545. Epub 2006 Dec 5.

Abstract

Polycomb group (PcG) proteins are chromatin modifiers that are necessary for the maintenance and renewal of embryonic and adult stem cells. However, overexpression of the PcG protein, Bmi-1, causes lymphoma in transgenic mice. We show that Bmi-1 is up-regulated in Hodgkin lymphoma (HL) cells by the Epstein-Barr virus (EBV) oncogene latent membrane protein-1 (LMP1) and that this up-regulation is mediated by NF-kappaB signaling. We also show that Bmi-1 is up-regulated by NF-kappaB in EBV-negative HL cells. Down-regulation of LMP1 and Bmi-1 decreased the survival of HL cells, suggesting that Bmi-1 may mediate the prosurvival effects of LMP1-induced NF-kappaB signaling in HL cells. Transcriptional targets of Bmi-1 were identified after its knockdown in an HL cell line. We show here that Bmi-1 and LMP1 down-regulate the ataxia telangiectasia-mutated (ATM) tumor suppressor and conclude that Bmi-1 contributes to LMP1-induced oncogenesis in HL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ataxia Telangiectasia Mutated Proteins
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Cell Line
  • Cell Survival
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Down-Regulation
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic*
  • Herpesvirus 4, Human / metabolism*
  • Hodgkin Disease / genetics
  • Hodgkin Disease / metabolism*
  • Hodgkin Disease / pathology
  • Humans
  • NF-kappa B / metabolism
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Polycomb Repressive Complex 1
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism
  • Up-Regulation
  • Viral Matrix Proteins / genetics
  • Viral Matrix Proteins / metabolism*

Substances

  • BMI1 protein, human
  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • EBV-associated membrane antigen, Epstein-Barr virus
  • NF-kappa B
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Repressor Proteins
  • Tumor Suppressor Proteins
  • Viral Matrix Proteins
  • Polycomb Repressive Complex 1
  • ATM protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • Atm protein, mouse
  • Protein Serine-Threonine Kinases