HPV16 E6 and E7 upregulate the histone lysine demethylase KDM2B through the c-MYC/miR-146a-5p axys

Oncogene. 2018 Mar;37(12):1654-1668. doi: 10.1038/s41388-017-0083-1. Epub 2018 Jan 16.

Abstract

Persistent infection by high-risk human papillomaviruses (HPVs) is associated with the development of cervical cancer and a subset of anogenital and head and neck squamous cell carcinomas. Abnormal expression of cellular microRNAs (miRNAs) plays an important role in the development of cancer, including HPV-related tumors. In this study, we demonstrated that miR-146a-5p was down-regulated by E6 and, less efficiently, by E7 of high-risk HPV16 in keratinocytes and the presence of low levels of this miRNA in cervical carcinoma cell lines and in high-risk HPV-positive cervical specimens. Down-regulation of miR-146a-5p was mediated at least in part by the transcription repressor c-MYC, through binding sites in the miR-146a promoter. Overexpression of miR-146a-5p significantly inhibited proliferation and migration of keratinocytes and cervical cancer cells. The histone demethylase KDM2B was validated as a new direct target of miR-146a-5p and two putative binding sites for miR-146a-5p were identified in its 3'UTR sequence. Western blot analysis and immunohistochemistry showed that KDM2B was overexpressed in HPV16 E6/E7-positive keratinocytes, in cervical cancer cell lines, and in a subset of invasive cervical carcinomas and HPV-positive laryngeal squamous cell carcinomas. In these tumors, KDM2B overexpression was associated with c-MYC copy number gain. In vitro, silencing of KDM2B inhibited proliferation of cervical cancer cells. In conclusion, this study identified a novel player, the hystone demethylase KDM2B, in HPV-mediated tumorigenesis. E6 and, less efficiently, E7 of high-risk HPV16 up-regulated KDM2B expression in human keratinocytes through a pathway involving overexpression of c-MYC, which in turn downregulated miR-146a-5p.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Transformation, Viral / genetics
  • Cells, Cultured
  • F-Box Proteins / genetics*
  • Female
  • Gene Expression Regulation, Enzymologic
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Infant, Newborn
  • Jumonji Domain-Containing Histone Demethylases / genetics*
  • Male
  • MicroRNAs / physiology*
  • Oncogene Proteins, Viral / physiology*
  • Papillomavirus E7 Proteins / physiology*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / physiology*
  • Repressor Proteins / physiology*
  • Signal Transduction / genetics
  • Up-Regulation / genetics
  • Uterine Cervical Neoplasms / genetics
  • Uterine Cervical Neoplasms / pathology

Substances

  • E6 protein, Human papillomavirus type 16
  • F-Box Proteins
  • MIRN146 microRNA, human
  • MYC protein, human
  • MicroRNAs
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • Proto-Oncogene Proteins c-myc
  • Repressor Proteins
  • oncogene protein E7, Human papillomavirus type 16
  • Jumonji Domain-Containing Histone Demethylases
  • KDM2A protein, human