Article Text

Download PDFPDF
Eradication of Helicobacter pylori infection reverses E-cadherin promoter hypermethylation
  1. A O O Chan1,
  2. J Z Peng1,
  3. S K Lam1,
  4. K C Lai1,
  5. M F Yuen1,
  6. H K L Cheung1,
  7. Y L Kwong1,
  8. A Rashid2,
  9. C K Chan1,
  10. B C-Y Wong1
  1. 1Department of Medicine, University of Hong Kong, Hong Kong
  2. 2Department of Pathology, University of Texas, MD Anderson Cancer Center, Houston, Texas, USA
  1. Correspondence to:
    Dr B C-Y Wong
    Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong; bcywong{at}


Background: E-cadherin methylation is important in gastric carcinogenesis. Reversing hypermethylation may halt the carcinogenic process. We have previously reported that Helicobacter pylori infection is associated with E-cadherin methylation in chronic gastritis patients.

Aim: To examine if eradication of H pylori could reverse E-cadherin methylation.

Methods: Patients with dyspepsia and positive for H pylori infection, with a mucosal biopsy showing chronic active gastritis, were randomised to receive H pylori eradication therapy (group 1, n = 41) or no treatment (group 2, n = 40), and were followed up prospectively. Gastric mucosae were taken for methylation assay at week 0 (before treatment) and week 6 (after treatment). Archived specimens of intestinal metaplasia with H pylori infection (n = 22) and without (n = 19) were retrieved for methylation analysis. Methylation was assessed using methylation specific polymerase chain reaction and sequencing.

Results: Methylation at E-cadherin was detected in 46% (19/41) and 17% (7/41) of patients at weeks 0 and 6, respectively, in group 1 (p = 0.004); 78.9% (15/19) of specimens were unmethylated after eradication of H pylori. Mucosal biopsy showed chronic inactive gastritis in 35 patients, intestinal metaplasia in one, and normal mucosa in five at week 6. Methylation was detected in 47.5% (19/40) and 52.5% (21/40) of patients at weeks 0 and 6, respectively, in group 2 (P = 0.5). Gastric mucosal biopsy showed persistent chronic active gastritis in all cases. Methylation frequency did not differ in H pylori positive or negative intestinal metaplastic specimens (72.7% v 63%; p = 0.5).

Conclusion:H pylori eradication therapy could reverse methylation in patients with chronic gastritis. This demonstrates an environmental effect on methylation.

  • PCR, polymerase chain reaction
  • MSP, methylation specific polymerase chain reaction
  • E-cadherin methylation
  • gastric cancer
  • intestinal metaplasia
  • Helicobacter pylori

Statistics from

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.


  • Conflict of interest: None declared.

  • The abstract was presented orally at the AGA Distinguished Abstract Plenary Session, GI Oncology Plenary Session: Frontiers of Clinical Medicine and Translational Research, Digestive Disease Week, New Orleans, USA, May 2004.