Relationship of Polymorphisms of MTHFR Gene and Hypermethylation of Tumor Suppressor Gene in Lung Cancers

Objective：To evaluate the possible association of the MTHFR gene C677T polymorphisms with the hypermethylation of p16 and MGMT gene in lung cancer. Methods：A retrospective case control study was designed in this investigation.The MTHFR genotypes of 93 cases and 106 controls were determined using a PCR-based restriction fragment length polymorphism(RFLP) method.The hypermethylation of p16 and MGMT gene in plasma of 93 cases of lung cancer by nested methylation specific polymerase chain reaction（nMSP）. Results：The frequencies of C/C,C/T,T/T genotypes of MTHFR gene C677T were 29%，49.5% and 21.5% in cases and 36%，51% and 19% in controls,respectively.No significant difference of genotype distribution was found. Aberrant methylation of the p16 gene was detected in 63 from 93 cases(68%),and methylation of the MGMT gene was detected in 48 from 93 cases(52%).There was no significant difference among the different genotypes. Conclusion：No association between MTHFR gene C677T variant genotypes were and lung cancer was suggested. MTHFR C677T variant genotypes was not the direct reason of methylation of tumor suppressor gene.