Background and objective: It has been proven that close relation was existed between XPD polymorphism G312A and lung cancer risk. However, some of the results are not consistent. The aim of this study is to explore the impact of DNA repair gene XPD polymorphism G312A on lung cancer risk.
Methods: The literatures eligible from PUBMED, EMBASE, CNKI and WANGFANG database were enrolled in the meta-analysis. Heterogeneity among combined studies was assessed. The pooled OR and 95%CI were calculated. The sensitivity analysis and the publication bias were evaluated by RevMan 5.0 and STATA 11.0.
Results: There were 6554 cases and 8322 controls from 18 studies included in the meta-analysis. In total, individuals with 312A allele and 312AA genotype showed increased lung cancer risk (A vs. G: OR = 1.06, 95% CI: 1.00-1.12; AA vs. AG+GG: OR = 1.20, 95% CI: 1.06-1.36; AA vs. GG: OR = 1.19, 95% CI: 1.04-1.36). In Asians, individuals with 312AA genotype showed 6.15 fold and 6.20 fold increased lung cancer risk in recessive genetic model and homogenous contrast respectively (AA vs. AG+GG: OR = 7.15, 95% CI: 1.90-26.94; AA vs. GG: OR = 7.20, 95% CI: 1.91-27.15). In Caucasians, individuals with 312AA genotype showed a 15% increased lung cancer risk (OR = 1.15, 95% CI: 1.01-1.31).
Conclusion: XPD 312A allele is risk allele for lung cancer. Individuals with AA genotype have higher risk of lung cancer, especially in Asians.
背景与目的: 已有的研究结果显示DNA修复基因XPD G312A多态位点与肺癌发生存在相关性，但研究结果尚未有一致性结论。本研究旨在通过meta分析的方法，综合评价DNA修复基因XPD G312A多态位点与肺癌发病风险的相关性。
方法: 检索PUBMED、EMBASE、清华CNKI全文数据库、万方全文数据库中XPD基因G312A多态位点与肺癌易感性关系的病例对照研究。对符合纳入标准的研究用meta分析的方法进行数据合并，采用RevMan 5.0和STATA 11.0评价研究间异质性，计算合并OR值及95%CI。并进行敏感性分析和发表偏倚检验。
结果: 共纳入18项研究，累计病例6 554例，对照8 322例。总体人群中A等位基因及AA基因型携带者肺癌风险明显升高（A vs G: OR=1.06, 95%CI: 1.00-1.12; AA vs AG+GG: OR=1.20, 95%CI: 1.06-1.36; AA vs GG: OR=1.19, 95%CI: 1.04-1.36）。亚洲人群中，AA基因型携带者肺癌风险明显升高（AA vs AG+GG: OR=7.15, 95%CI: 1.90-26.94; AA vs GG:OR=7.20, 95%CI: 1.91-27.15）。高加索人群中，AA基因型携带者肺癌风险升高（AA vs AG+GG: OR=1.15, 95%CI: 1.01-1.31）。
结论: XPD 312A等位基因为肺癌发生的风险等位基因，AA基因型携带者肺癌风险升高，尤其在亚洲人群这种影响更为明显。