Helicobacter pylori Is Associated with miR-133a Expression through Promoter Methylation in Gastric Carcinogenesis

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Updated: Feb 22, 2026

Genome-Wide Analysis of DNA Methylation in Gastrointestinal Cancer
07:50

Genome-Wide Analysis of DNA Methylation in Gastrointestinal Cancer

Published on: September 18, 2020

6.2K

Joo Hyun Lim1,2, Sang Gyun Kim2, Ji Min Choi1

  • 1Department of Internal Medicine and Healthcare Research Institute, Healthcare System Gangnam Center, Seoul National University Hospital, Seoul, Korea.

Gut and Liver
|September 28, 2017
PubMed
Abstract

Insights

Helicobacter pylori eradication can reverse epigenetic silencing of miR-133a, a microRNA (miRNA) involved in gastric cancer. This finding suggests a potential therapeutic strategy for H. pylori-associated gastric carcinogenesis.

Area of Science:

  • Epigenetics
  • Molecular Biology
  • Oncology

Background:

  • Helicobacter pylori infection is a major risk factor for gastric cancer.
  • Epigenetic silencing of microRNAs (miRNAs) plays a role in H. pylori-induced gastric carcinogenesis.
  • Specific miRNAs like miR-133a are implicated in this process.

Purpose of the Study:

  • To investigate if H. pylori eradication can reverse the epigenetic silencing of specific miRNAs.
  • To determine the role of miR-133a in H. pylori-associated gastric carcinogenesis.
  • To assess the impact of H. pylori eradication on miRNA expression and methylation.

Main Methods:

  • Examined expression and promoter methylation of miR-34b/c, miR-133a, let-7a, and let-7i in gastric cancer cell lines and human tissues.
  • Assessed miRNA changes in H. pylori-positive patients before and after treatment, comparing eradication and non-eradication groups.
  • Utilized demethylation in cell lines to identify epigenetically controlled miRNAs.

Main Results:

  • miR-133a and miR-34b/c showed epigenetic silencing in gastric cancer cell lines.
  • Promoter methylation of miR-34b/c and miR-133a increased progressively from control to gastritis to cancer tissues.
  • H. pylori eradication led to decreased miR-133a promoter methylation and increased expression.

Conclusions:

  • H. pylori eradication can reverse the methylation-based silencing of miR-133a.
  • miR-133a is involved in H. pylori-induced gastric carcinogenesis.
  • Targeting epigenetic modifications may offer a therapeutic approach for H. pylori-related gastric cancer.
Keywords:
Helicobacter pyloriMethylationMicroRNAsStomach neoplasms

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