title: Higher number of Helicobacter pylori CagA EPIYA C phosphorylation sites increases the risk of gastric cancer, but not duodenal ulcer.
abstract: BACKGROUND
  Helicobacter pylori infection is one of the most common infections worldwide and is associated with gastric cancer and peptic ulcer. Bacterial virulence factors such as CagA have been shown to increase the risk of both diseases. Studies have suggested a causal role for CagA EPIYA polymorphisms in gastric carcinogenesis, and it has been shown to be geographically diverse. We studied associations between H. pylori CagA EPIYA patterns and gastric cancer and duodenal ulcer, in an ethnically admixed Western population from Brazil. CagA EPIYA was determined by PCR and confirmed by sequencing. A total of 436 patients were included, being 188 with gastric cancer, 112 with duodenal ulcer and 136 with gastritis.
  
  
  RESULTS
  The number of EPIYA C segments was significantly associated with the increased risk of gastric carcinoma (OR=3.08, 95% CI=1.74 to 5.45, p<10-3) even after adjustment for age and gender. Higher number of EPIYA C segments was also associated with gastric atrophy (p=0.04) and intestinal metaplasia (p=0.007). Furthermore, patients infected by cagA strains possessing more than one EPIYA C segment showed decreased serum levels of pepsinogen I in comparison with those infected by strains containing one or less EPIYA C repeat. Otherwise, the number of EPIYA C segments did not associate with duodenal ulcer.
  
  
  CONCLUSIONS
  Our results demonstrate that infection with H. pylori strains harbouring more than one CagA EPIYA C motif was clearly associated with gastric cancer, but not with duodenal ulcer.Higher number of EPIYA C segments was also associated with gastric precancerous lesions as demonstrated by histological gastric atrophic and metaplastic changes and decreased serum levels of pepsinogen I.
authors: Laboratory of Research in Bacteriology, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av, Alfredo Balena, 190, sala 216, Belo Horizonte, Minas Gerais, 30130-100, Brazil.
authors: Sérgio A
authors: SA
authors: Batista
authors: Gifone A
authors: GA
authors: Rocha
authors: Andreia M C
authors: AM
authors: Rocha
authors: Ivan E B
authors: IE
authors: Saraiva
authors: Mônica M D A
authors: MM
authors: Cabral
authors: Rodrigo C
authors: RC
authors: Oliveira
authors: Dulciene M M
authors: DM
authors: Queiroz
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001938:Brazil / Q000453:epidemiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004381:Duodenal Ulcer / Q000453:epidemiology* / Q000382:microbiology; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics* / Q000472:pathogenicity*; D006801:Humans; D008875:Middle Aged; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C080866:cagA protein, Helicobacter pylori