Article Text

PDF
Immunohistochemical study of nuclear factor-κB activity and interleukin-8 abundance in oesophageal adenocarcinoma; a useful strategy for monitoring these biomarkers
  1. G J S Jenkins1,
  2. J Mikhail1,
  3. A Alhamdani2,
  4. T H Brown2,
  5. S Caplin2,
  6. J M Manson3,
  7. R Bowden4,
  8. N Toffazal4,
  9. A P Griffiths4,
  10. J M Parry1,
  11. J N Baxter2
  1. 1
    Swansea School of Medicine, University of Wales Swansea, Swansea, UK
  2. 2
    Department of Surgery, Morriston Hospital, Swansea, UK
  3. 3
    Department of Surgery, Singleton Hospital, Swansea, UK
  4. 4
    Department of Pathology, Swansea NHS Trust, Swansea, UK
  1. Dr G J S Jenkins, Swansea School of Medicine, University of Wales Swansea, Swansea SA28PP, UK; g.j.jenkins{at}swansea.ac.uk

Abstract

Aims: To determine if immunohistochemistry (IHC) could be used to monitor nuclear factor-κB (NF-κB) activity in oesophageal adenocarcinoma and pre-malignant (Barrett’s) oesophageal tissues, relative to normal oesophageal mucosa. The pro-inflammatory cytokine interleukin-8 (IL-8), a transcriptional target of NF-κB, was also studied to better understand NF-κB functionality; its RNA and protein levels were assessed in oesophageal tissues.

Methods: IHC was employed using an antibody against the nuclear localisation sequence (NLS) of the p65 subunit as well as an antibody against IL-8. To assess NF-κB function, changes in gene expression of NF-κB controlled genes (IL-8 and I-κB) were also assessed in the histological sequence using real-time PCR. More global expression changes were also studied using membrane arrays.

Results: IHC was effective at monitoring overall NF-κB activity and IL-8 abundance. This method also allowed NF-κB activity and IL-8 abundance to be pinpointed in specific cell types. There were significant increases in nuclear NF-κB activity and IL-8 abundance across the histological series. Gene expression analysis also showed consistent up-regulation of IL-8, confirming the IHC data and showing enhanced transcriptional NF-κB activity. I-κB (another NF-κB target) showed down-regulation in dysplastic and adenocarcinoma tissues. Down-regulation of I-κB gene expression may partly explain increased NF-κB activity.

Conclusion: IHC, using antibodies against the NLS of p65, may be useful in monitoring overall NF-κB activity in oesophageal tissues. As IHC is amenable to high-throughput screening (whereas traditional electrophoretic mobility shift assay methods are not), this may lead to the development of a better screening tool for early cancer risk.

  • immunohistochemistry
  • NF-kB
  • IL-8
  • Barrett’s oesophagus
  • adenocarcinoma
  • biomarker

Statistics from Altmetric.com

Footnotes

  • Funding: This work was partly funded by the Welsh Office for Research and Development (Grant WS01/1/009).

  • Competing interests: None.

  • Abbreviations:
    IHC
    immunohistochemistry
    IL
    interleukin
    NF-κB
    nuclear factor-κB
    NLS
    nuclear localisation sequence

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.