title: Influence of methylenetetrahydrofolate reductase C677T polymorphism on the risk of lung cancer and the clinical response to platinum-based chemotherapy for advanced non-small cell lung cancer: an updated meta-analysis.
abstract: OBJECTIVE
  Methylenetetrahydrofolate reductase (MTHFR) has been implicated in lung cancer risk and response to platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). However, the results are controversial. We performed meta-analysis to investigate the effect of MTHFR C677T polymorphism on lung cancer risk and response to platinum-based chemotherapy in advanced NSCLC.
  
  
  METHODS
  The databases of PubMed, Ovid, Wanfang and Chinese Biomedicine were searched for eligible studies. Nineteen studies on MTHFR C677T polymorphism and lung cancer risk and three articles on C677T polymorphism and response to platinum-based chemotherapy in advanced NSCLC, were identified.
  
  
  RESULTS
  The results indicated that the allelic contrast, homozygous contrast and recessive model of the MTHFR C677T polymorphism were associated significantly with increased lung cancer risk. In the subgroup analysis, the C677T polymorphism was significantly correlated with an increased risk of NSCLC, with the exception of the recessive model. The dominant model and the variant T allele showed a significant association with lung cancer susceptibility of ever smokers. Male TT homozygote carriers had a higher susceptibility, but the allelic contrast and homozygote model had a protective effect in females. No relationship was observed for SCLC in any comparison model. In addition, MTHFR 677TT homozygote carriers had a better response to platinum-based chemotherapy in advanced NSCLC in the recessive model.
  
  
  CONCLUSIONS
  The MTHFR C677T polymorphism might be a genetic marker for lung cancer risk or response to platinum- based chemotherapy in advanced NSCLC. However, our results require further verification.
authors.affiliation: Department of Respiratory Diseases, Huashan Hospital, Fudan University, No.12 of Wulumuqi Middle Road, Shanghai 200040, China. xdchen8@hotmail.com.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhu
authors.forename: Yi
authors.initials: Y
authors.lastname: Gong
authors.forename: Jian
authors.initials: J
authors.lastname: He
authors.forename: Jingwen
authors.initials: J
authors.lastname: Xia
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Chen
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000235:genetics*; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D010984:Platinum / Q000627:therapeutic use*; D011110:Polymorphism, Genetic / Q000235:genetics
chemical_list: D010984:Platinum; D042965:Methylenetetrahydrofolate Reductase (NADPH2)
keywords: C677T; MTHFR; lung cancer; platinum-based chemotherapy; polymorphism