Association between CYP2D6 polymorphisms and lung cancer risk: an up-date meta-analysis

Background: Genetic variants in metabolic enzymes of CYP2D6 have been shown to be associated with the pathogenesis of lung cancer. However, the results remain inconsistent. The aim of the present study was to explore the exact role of CYP2D6 polymorphisms in lung cancer risk. Methods: Online electronic databases were searched to retrieve related articles published between 2000 and 2014. The odds ratio ( OR) with its 95% confidence interval (CI) were employed to assess these associations. Results: A total of 11 case-control studies were screened out, including 1634 cases and 1626 healthy controls. No significant heterogeneity was found between studies. Our results found that the T allele and TT genotype of C188T polymorphism, the C allele and CC genotype of G4268C variant, were associated with increased the risk of lung cancer. Subgroup analysis by hyphology of lung cancer showed that TT genotype of C188T polymorphism was significantly associated with adenocarcinoma risk. No relationship was found between G1934A polymorphism and lung cancer. Conclusions: Our results found that polymorphisms of C188T and G4268C in CYP2D6 gene were associated with increased the risk of lung cancer. Further large-scale studies concerning the interaction of gene-gene or gene-environment are needed.