title: Methylenetetrahydrofolate reductase C677T polymorphism in patients with lung cancer in a Korean population.
abstract: BACKGROUND
  This study was designed to investigate an association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of lung cancer in a Korean population.
  
  
  METHODS
  We conducted a large-scale, case-control study involving 3938 patients with newly diagnosed lung cancer and 1700 healthy controls. Genotyping was performed with peripheral blood DNA for MTHFR C677T polymorphisms. Statistical significance was estimated by logistic regression analysis.
  
  
  RESULTS
  The MTHFR C677T frequencies of CC, CT, and TT genotypes were 34.5%, 48.5%, and 17% among lung cancer patients, and 31.8%, 50.7%, and 17.5% in the controls, respectively. The MTHFR 677CT and TT genotype showed a weak protection against lung cancer compared with the homozygous CC genotype, although the results did not reach statistical significance. The age- and gender-adjusted odds ratio (OR) of overall lung cancer was 0.90 (95% confidence interval (CI), 0.77-1.04) for MTHFR 677 CT and 0.88 (95% CI, 0.71-1.07) for MTHFR 677TT. However, after stratification analysis by histological type, the MTHFR 677CT genotype showed a significantly decreased risk for squamous cell carcinoma (age- and gender-adjusted OR, 0.78; 95% CI, 0.64-0.96). The combination of 677 TT homozygous with 677 CT heterozygous also appeared to have a protection effect on the risk of squamous cell carcinoma. We observed no significant interaction between the MTHFR C677T polymorphism and age and gender or smoking habit.
  
  
  CONCLUSIONS
  This is the first reported study focusing on the association between MTHFR C677T polymorphisms and the risk of lung cancer in a Korean population. The T allele was found to provide a weak protective association with lung squamous cell carcinoma.
authors.affiliation: Department of Public Health, Qingdao University Medical College, Qingdao, China.
authors.forename: Lian-Hua
authors.initials: LH
authors.lastname: Cui
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Shin
authors.forename: Hee Nam
authors.initials: HN
authors.lastname: Kim
authors.forename: Hye-Rim
authors.initials: HR
authors.lastname: Song
authors.forename: Jin-Mei
authors.initials: JM
authors.lastname: Piao
authors.forename: Sun-Seog
authors.initials: SS
authors.lastname: Kweon
authors.forename: Jin-Su
authors.initials: JS
authors.lastname: Choi
authors.forename: Woo-Jun
authors.initials: WJ
authors.lastname: Yun
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: In-Jae
authors.initials: IJ
authors.lastname: Oh
authors.forename: Kyu-Sik
authors.initials: KS
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000235:genetics; D000368:Aged; D000483:Alleles; D001483:Base Sequence; D018287:Carcinoma, Large Cell / Q000201:enzymology / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000235:genetics; D016022:Case-Control Studies; D016001:Confidence Intervals; D017931:DNA Primers / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000235:genetics*; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D056910:Republic of Korea; D012307:Risk Factors; D055752:Small Cell Lung Carcinoma / Q000201:enzymology / Q000235:genetics
chemical_list: D017931:DNA Primers; D004273:DNA, Neoplasm; D042965:Methylenetetrahydrofolate Reductase (NADPH2)