title: Identification of a genetic marker of Helicobacter pylori strains involved in gastric extranodal marginal zone B cell lymphoma of the MALT-type.
abstract: OBJECTIVE
  Gastric extranodal marginal zone B cell lymphoma of the mucosa associated lymphoid tissue (MALT)-type (MZBL) is a rare complication of Helicobacter pylori infection. Currently, no bacterial factor has been associated with the development of this disease. Our aim was to identify genes associated with lymphoma development.
  
  
  METHODS
  We used subtractive hybridisation as a tool for comparative genomics between H pylori strains isolated from a patient with gastric MZBL and from a patient with gastritis only.
  
  
  RESULTS
  When gastric MZBL strains were compared with gastritis strains, two open reading frames (ORFs) were significantly associated with gastric MZBL: JHP950 (74.4% v 48.7%, respectively; p = 0.023) and JHP1462 (25.6% v 2.6%, respectively; p = 0.004). The prevalence of JHP950 was 48.8% (p = 0.024) in duodenal ulcer strains and 39.3% (p = 0.006) in gastric adenocarcinoma strains, which makes this ORF a specific marker for gastric MZBL strains. In contrast, the prevalence of JHP1462 was 16% (p = 0.545) and 35.7% (p = 0.429) in duodenal ulcer and adenocarcinoma strains, respectively. These ORFs were present in reference strain J99 but not in reference strain 26695. JHP950 is located in the plasticity zone whereas the other, JHP1462, is located outside. Both encode for H pylori putative proteins with unknown functions.
  
  
  CONCLUSIONS
  Despite its low prevalence, the ORF JHP1462 can be considered a candidate marker for H pylori strains involved in severe gastroduodenal diseases. In contrast, the ORF JHP950 has a high prevalence, and is the first candidate marker for strains giving rise to an increased risk of gastric MZBL strains. Further confirmation in other studies is needed.
authors.affiliation: Laboratoire de Bactériologie, Université Victor Segalen Bordeaux 2, Bordeaux, France.
authors.forename: P
authors.initials: P
authors.lastname: Lehours
authors.forename: S
authors.initials: S
authors.lastname: Dupouy
authors.forename: B
authors.initials: B
authors.lastname: Bergey
authors.forename: A
authors.initials: A
authors.lastname: Ruskoné-Foumestraux
authors.forename: J C
authors.initials: JC
authors.lastname: Delchier
authors.forename: R
authors.initials: R
authors.lastname: Rad
authors.forename: F
authors.initials: F
authors.lastname: Richy
authors.forename: J
authors.initials: J
authors.lastname: Tankovic
authors.forename: F
authors.initials: F
authors.lastname: Zerbib
authors.forename: F
authors.initials: F
authors.lastname: Mégraud
authors.forename: A
authors.initials: A
authors.lastname: Ménard
mesh_terms: D000230:Adenocarcinoma / Q000382:microbiology; D000328:Adult; D000368:Aged; D004269:DNA, Bacterial / Q000235:genetics; D004381:Duodenal Ulcer / Q000382:microbiology; D005260:Female; D005756:Gastritis / Q000382:microbiology; D015723:Gene Library; D005819:Genetic Markers; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization / Q000379:methods; D016366:Open Reading Frames / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D013274:Stomach Neoplasms / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial; D005819:Genetic Markers