Mn-SOD and CuZn-SOD polymorphisms and interactions with risk factors in gastric cancer.
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.
Yi
Jian-Feng
JF
The First College of Clinical Medicine of Lanzhou University, Lanzhou 730000, Gansu Province, China.
Li
Yu-Min
YM
Liu
Tao
T
He
Wen-Ting
WT
Li
Xun
X
Zhou
Wen-Ce
WC
Kang
Shi-Liang
SL
Zeng
Xiang-Ting
XT
Zhang
Jun-Qiang
JQ
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*
D013482:Superoxide Dismutase