• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Analysis of gastric carcinogenesis induced by H.pylonriinfection: analysis of Asian paradox

Research Project

Project/Area Number 16590613
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Gastroenterology
Research InstitutionFukui Prefectural University

Principal Investigator

KATO Takuji  Fukui Prefectural University, Faculty of Nursing and Welfare, Professor, 看護福祉学部, 教授 (70145902)

Co-Investigator(Kenkyū-buntansha) AZUMA Takeshi  Kobe University, Professor, 医学部, 教授 (60221040)
Project Period (FY) 2004 – 2005
Project Status Completed (Fiscal Year 2005)
Budget Amount *help
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2005: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2004: ¥2,700,000 (Direct Cost: ¥2,700,000)
KeywordsH.pylori / CagA / Gastric cancer / H.pylori / VacA
Research Abstract

Helicobacter pylori (H.pylori) is a human pathogen responsible for chronic active gastritis, and infection with this organism is an important risk factor for gastric cancer. The severity of H.pylori-related disease is correlated with the presence of a cag pathogenicity island (PAI). Genetic diversity within the cag PAI may have a modifying effect on the pathogenic potential of the infecting strain. We analyzed complete cag PAI sequences of 11 representative Japanese strains, and examined the relationship between the diversity of cag PAI and clinical features. The cag PAI genes were divided into two major groups, a Western and a East Asian group, by phylogenetic analysis based on the entire cag PAI sequences. Our molecular analysis has provided the pathological actions of CagA (cagA gene is located in cag PAI) on gastric epithelial cells. CagA is injected into epithelial cells via the type IV secretion system and undergoes tyrosine phosphorylation in the cells. In addition, translocated CagA forms a physical complex with SHP-2. There are two major CagA subtypes ; the East Asian and the Western type. The East Asian CagA protein possesses stronger SHP-2 binding activity than the Western CagA. The grades of inflammation, activity of gastritis, and atrophy are significantly higher in gastritis patients infected with the East Asian CagA-positive strain than in gastritis patients infected with the cagA-negative or Western CagA-positive strains. The prevalence of the East Asian CagA-positive strain is associated with the mortality rate of gastric cancer in Asia. Endemic circulation of H.pylori populations carrying biologically more active CagA proteins in East Asian countries, where the mortality rate of gastric cancer is among the highest in the world, may be involved in increasing the risk of gastric cancer in these populations.

Report

(3 results)
  • 2005 Annual Research Report   Final Research Report Summary
  • 2004 Annual Research Report
  • Research Products

    (4 results)

All 2005 2004

All Journal Article (4 results)

  • [Journal Article] Identification of Helicobacter pylori and the cagAgenotype in gastric biopsies using highly sensitive real-time PCR as a new diagnostic tool.2005

    • Author(s)
      Yamazaki S
    • Journal Title

      FEMS Immunol MedMicrobiol 44

      Pages: 261-268

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2005 Final Research Report Summary
  • [Journal Article] Identification of Helicobacter pylori and the cagA genotype in gastric biopsies using highly sensitive real-time PCR as a new diagnostic tool.2005

    • Author(s)
      Shiho Yamazaki
    • Journal Title

      FEMS Immunol Med Microbiol 44

      Pages: 261-268

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2005 Final Research Report Summary
  • [Journal Article] Identitication of Helicobacter pylori and the cagAgenotype in gastric biopsies using highly sensitive real-time PCR as a new diagnostic tool.2005

    • Author(s)
      Yamazaki S
    • Journal Title

      FEMS Immunol MedMicrobiol 44

      Pages: 261-268

    • Related Report
      2005 Annual Research Report
  • [Journal Article] Diversity of vacA and cagA genes of Helicobacter pylori in Japanese children.2004

    • Author(s)
      Azuma T
    • Journal Title

      Aliment.Pharmacol.Ther. 20(Suppl.1)

      Pages: 7-12

    • Related Report
      2004 Annual Research Report

URL: 

Published: 2004-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi