title: Folate intake, methylenetetrahydrofolate reductase polymorphisms in association with the prognosis of esophageal squamous cell carcinoma.
abstract: OBJECTIVE
  An epidemiological study was conducted based on an esophageal cancer patient's cohort to investigate the association of folate intake and MTHFR C677T polymorphism with the prognosis of esophageal cancer in a Chinese population.
  
  
  METHODS
  167 patients aged 37-75 years who had histological confirmed diagnosis of esophageal squamous cell cancer were collected from Jan. 2006 to Jan. 2008. MTHFR genotypes at the C677T site were analyzed by PCR-based RFLP methods, and the folate intake was computed by multiplying the food intake (in grams) and the folate content (per gram) of food in our questionnaire.
  
  
  RESULTS
  We found associations between the prognosis of esophageal cancer and smoking status, T and N stages. Individuals carrying the MTHFR 677CT and TT genotypes showed a shorter survival time than with the CC genotype, with adjusted HRs (95% CI) of 1.20 (0.56-2.15) and 2.29 (1.30-4.28), respectively. Similarly, those carrying MTHFR 677T allele had a 1.86-fold risk of death. A higher folate concentration showed a significant decreased risk of death, with an HR (95% CI) of 0.45 (0.18-0.87). Individuals with high folate intake and the MTHFR 677CC genotype showed a significant decreased risk of esophageal cancer (0.43, 0.25-0.89).
  
  
  CONCLUSIONS
  Our findings supports the hypothesis that high folate intake and active MTHFR C677T polymorphism may exert protective roles in the prognosis of esophageal cancer in the Chinese population.
authors.affiliation: Department of Cadre Ward, The General Hospital of Chengdu Military Area, Chengdu, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Jing
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Huang
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Duan
authors.forename: Xinrong
authors.initials: X
authors.lastname: Xiao
authors.forename: Ru
authors.initials: R
authors.lastname: Zhang
authors.forename: Jianqing
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D004938:Esophageal Neoplasms / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005492:Folic Acid / Q000378:metabolism*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor; D005492:Folic Acid; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)