Repression of Hox genes by LMP1 in nasopharyngeal carcinoma and modulation of glycolytic pathway genes by HoxC8

Oncogene. 2015 Dec 10;34(50):6079-91. doi: 10.1038/onc.2015.53. Epub 2015 Mar 9.

Abstract

Epstein-Barr virus (EBV) causes human lymphoid malignancies, and the EBV product latent membrane protein 1 (LMP1) has been identified as an oncogene in epithelial carcinomas such as nasopharyngeal carcinoma (NPC). EBV can epigenetically reprogram lymphocyte-specific processes and induce cell immortalization. However, the interplay between LMP1 and the NPC host cell remains largely unknown. Here, we report that LMP1 is important to establish the Hox gene expression signature in NPC cell lines and tumor biopsies. LMP1 induces repression of several Hox genes in part via stalling of RNA polymerase II (RNA Pol II). Pol II stalling can be overcome by irradiation involving the epigenetic regulator TET3. Furthermore, we report that HoxC8, one of the genes silenced by LMP1, has a role in tumor growth. Ectopic expression of HoxC8 inhibits NPC cell growth in vitro and in vivo, modulates glycolysis and regulates the expression of tricarboxylic acid (TCA) cycle-related genes. We propose that viral latency products may repress via stalling key mediators that in turn modulate glycolysis.

Publication types

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

MeSH terms

  • Cells, Cultured
  • Citric Acid Cycle
  • DNA Methylation
  • Dioxygenases / physiology
  • Genes, Homeobox / physiology*
  • Glycolysis
  • Homeodomain Proteins / physiology*
  • Humans
  • Nasopharyngeal Neoplasms / genetics*
  • Nasopharyngeal Neoplasms / metabolism
  • RNA Polymerase II / metabolism
  • Viral Matrix Proteins / physiology*

Substances

  • EBV-associated membrane antigen, Epstein-Barr virus
  • HOXC8 protein, human
  • Homeodomain Proteins
  • Viral Matrix Proteins
  • TET3 protein, human
  • Dioxygenases
  • RNA Polymerase II