title: Mn-SOD and CuZn-SOD polymorphisms and interactions with risk factors in gastric cancer.
abstract: OBJECTIVE
  To investigate the effects of superoxide dismutase (SOD) polymorphisms (rs4998557, rs4880), Helicobacter pylori (H. pylori) infection and environmental factors in gastric cancer (GC) and malignant potential of gastric precancerous lesions (GPL).
  
  
  METHODS
  Copper-zinc superoxide dismutase (SOD1, CuZn-SOD)-G7958A (rs4998557) and manganese superoxide dismutase (SOD2, Mn-SOD)-Val16Ala (rs4880) polymorphisms were genotyped by SNaPshot multiplex polymerase chain reaction (PCR) in 145 patients with GPL (87 cases of gastric ulcer, 33 cases of gastric polyps and 25 cases of atrophic gastritis), 140 patients with GC and 147 healthy controls. H. pylori infection was detected by immunoblotting analysis.
  
  
  RESULTS
  The SOD1-7958A allele was associated with a higher risk of gastric cancer [odds ratio (OR) = 3.01, 95% confidence intervals (95% CI): 1.83-4.95]. SOD2-16Ala/Val genotype was a risk factor for malignant potential of GPL (OR = 2.04, 95% CI: 1.19-3.49). SOD2-16Ala/- genotype increased the risk of gastric cancer (OR = 2.85, 95% CI: 1.66-4.89). SOD1-7958A/- genotype, SOD2-16Ala/- genotype, alcohol drinking, positive family history and type I H. pylori infection were associated with risk of gastric cancer, and there were additive interactions between the two genotypes and the other three risk factors. SOD2-16Ala/Val genotype and positive family history were associated with malignant potential of GPL and jointly contributed to a higher risk for malignant potential of GPL (OR = 7.71, 95% CI: 2.10-28.22). SOD1-7958A/- genotype and SOD2-16Ala/- genotype jointly contributed to a higher risk for gastric cancer (OR = 6.43, 95% CI: 3.20-12.91).
  
  
  CONCLUSIONS
  SOD1-7958A/- and SOD2-16Ala/-genotypes increase the risk of gastric cancer in Chinese Han population. SOD2-16Ala/-genotype is associated with malignant potential of GPL.
authors.affiliation: The First College of Clinical Medicine of Lanzhou University, Lanzhou 730000, Gansu Province, China.
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Yi
authors.forename: Yu-Min
authors.initials: YM
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.forename: Wen-Ting
authors.initials: WT
authors.lastname: He
authors.forename: Xun
authors.initials: X
authors.lastname: Li
authors.forename: Wen-Ce
authors.initials: WC
authors.lastname: Zhou
authors.forename: Shi-Liang
authors.initials: SL
authors.lastname: Kang
authors.forename: Xiang-Ting
authors.initials: XT
authors.lastname: Zeng
authors.forename: Jun-Qiang
authors.initials: JQ
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D044466:Asian People / Q000235:genetics; D005006:Ethnicity / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D016481:Helicobacter Infections / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D011230:Precancerous Conditions; D013274:Stomach Neoplasms / Q000201:enzymology / Q000235:genetics / Q000382:microbiology; D013482:Superoxide Dismutase / Q000235:genetics*
chemical_list: D013482:Superoxide Dismutase