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Updated: Jun 6, 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

XRCC1 downregulated through promoter hypermethylation is involved in human gastric carcinogenesis

Ping Wang1, Jie Ting Tang, Yan Shen Peng

  • 1Department of Gastroenterology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai Institute of Digestive Disease, Shanghai, China.

Journal of Digestive Diseases
|November 25, 2010
PubMed
Abstract

Insights

X-ray repair cross-complementing gene 1 (XRCC1) expression decreases during gastric carcinogenesis. Promoter hypermethylation is identified as a key mechanism contributing to this XRCC1 downregulation in stomach cancer development.

Area of Science:

  • Molecular Biology
  • Oncology
  • Genetics

Background:

  • Gastric cancer is a significant global health concern.
  • Understanding the molecular mechanisms underlying gastric carcinogenesis is crucial for developing effective diagnostic and therapeutic strategies.

Purpose of the Study:

  • To investigate the expression patterns and methylation status of X-ray repair cross-complementing gene 1 (XRCC1) in gastric carcinogenesis.
  • To elucidate the role of XRCC1 alterations in the molecular pathogenesis of gastric cancer.

Main Methods:

  • Utilized methyl binding domain protein (MBD) immunoprecipitation and promoter microarray to identify methylation-sensitive genes.
  • Assessed XRCC1 protein and mRNA expression via immunohistochemistry and real-time PCR.
  • Analyzed XRCC1 methylation status and polymorphisms using methylation-specific PCR, bisulfite sequencing, and direct DNA sequencing.

Main Results:

  • XRCC1 was identified as a methylation-sensitive gene.
  • XRCC1 protein and mRNA expression significantly decreased with gastric carcinogenesis progression.
  • Increased XRCC1 methylation was observed in gastric cancer tissues, correlating with its downregulation.

Conclusions:

  • XRCC1 expression is significantly downregulated during gastric carcinogenesis.
  • Promoter hypermethylation is a key molecular mechanism contributing to XRCC1 downregulation in gastric cancer.

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