Evidence for possible role of toll-like receptor 3 mediating virus-induced progression of pituitary adenomas

Mol Cell Endocrinol. 2016 May 5;426:22-32. doi: 10.1016/j.mce.2016.02.009. Epub 2016 Feb 15.


Tumor-related viruses are known to be involved in initiation and progression of certain tumors. However, the relationship between virus and pituitary adenomas (PAs) remains unknown. Here, we investigated infection status of three types of viruses (HPV16, HHV6B and HSV1) and expression level of toll-like receptor 3 (TLR3) in 60 human PA samples. We also determined the role of TLR3 signaling pathway on a PA cell line (GH3). We firstly found that positive rates of HPV16 and HHV6B infection were significantly higher in invasive PA samples than in noninvasive samples (P < 0.01). Similarly, TLR3 mRNA and protein expression also increased in invasive PA samples (P < 0.01). In vitro analysis indicated that GH3 cell proliferation and survival were enhanced by TLR3 activation, which was accompanied by NF-κB activation. Our data indicate that HPV16 and HHV6B viruses may be involved in promoting the progression of PA by activating the TLR3 signaling pathway.

Keywords: Pituitary adenoma; Progression; Toll-like receptor 3; Viruses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoma / metabolism*
  • Adenoma / pathology
  • Adenoma / virology
  • Adult
  • Aged
  • Animals
  • Apoptosis
  • Cell Line, Tumor
  • Cell Proliferation
  • Disease Progression
  • Female
  • Herpesvirus 6, Human / physiology
  • Human papillomavirus 16 / physiology
  • Humans
  • Male
  • Middle Aged
  • Papillomavirus Infections / metabolism*
  • Papillomavirus Infections / pathology
  • Pituitary Neoplasms / metabolism*
  • Pituitary Neoplasms / pathology
  • Pituitary Neoplasms / virology
  • Rats
  • Roseolovirus Infections / metabolism*
  • Roseolovirus Infections / pathology
  • Signal Transduction
  • Toll-Like Receptor 3 / metabolism*


  • TLR3 protein, human
  • Toll-Like Receptor 3