Open AccessGenetic factors involved in the development of Helicobacter pylori ‐related gastric cancer
Author(s) -
Hamajima Nobuyuki,
Naito Mariko,
Kondo Takaaki,
Goto Yasuyuki
Publication year - 2006
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/j.1349-7006.2006.00290.x
Subject(s) - helicobacter pylori , cancer , genotype , carcinogenesis , atrophy , biology , immunology , genetics , medicine , gastroenterology , cancer research , gene
Developmental process to gastric cancer by Helicobacter pylori infection consists of three steps: (1) H. pylori infection; (2) gastric atrophy development; and (3) carcinogenesis. In each step, genetic traits may influence the process, interacting with lifestyle. In the step of H. pylori infection, two lines of genetic polymorphisms were assumed: one influencing gastric acid inhibition interacting with smoking, and the other concerning innate immune response attenuation. The former includes functional polymorphisms of IL‐1B (C‐31T or tightly linked T‐511C), and TNF‐A (T‐1031C and C‐857T), and the latter possibly includes NQO1 C609T. In the step to gastric atrophy, polymorphisms pertaining to the signal transduction from cytotoxin‐associated gene A ( PTPN11 A/G at intron 3) and to T‐cell responses ( IL‐2 T‐330G and IL‐13 C‐1111T) were hypothesized. There are a limited number of epidemiological genotype studies on the final step of literal carcinogenesis, potentially interacting with smoking, a low vegetable and fruit intake, and salty foods, the well‐documented risk factors. In past case‐control studies on the associations between genotype and gastric cancer risk, the cases consisted of H. pylori ‐related and unrelated gastric cancer patients and the controls consisted of individuals including the uninfected ( H. pylori unexposed and exposed) and the infected with and without gastric atrophy. Accordingly, it was not clear whether the observed risk was for H. pylori ‐related or ‐unrelated gastric cancer, nor which step was involved in the observed associations even when nearly all cases were H. pylori ‐related. In order to elucidate the genetic traits of H. pylori ‐related gastric cancer, stepwise evaluation will be required. ( Cancer Sci 2006; 97: 1129–1138)