Smoking and hOGG1 Ser326Cys polymorphism contribute to lung cancer risk: evidence from a meta-analysis

The human 8-oxoguanine DNA glycosylase (hOGG1) gene plays an important role in the repair of oxidatively damaged DNA base lesions and its functional single nucleotide polymorphisms (SNPs) may alter DNA repair capacity and thus contributes to cancer susceptibility. Numerous studies have investigated the association between hOGG1 Ser326Cys polymorphism and lung cancer susceptibility; however, the conclusions are still inconclusive. We searched eligible publications from MEDLINE, EMBASE, and CBM and performed a meta-analysis to assess the associations between hOGG1 Ser326Cys polymorphism and lung cancer risk. Pooled odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated to estimate risk associations, and false-positive report probability (FPRP) analysis was also carried out to evaluate significant findings. A total of 31 investigations with 10,220 cases and 12,284 controls were identified. When all studies were pooled, a significantly increased overall lung cancer risk was found (Cys/Cys vs. Ser/Ser: OR = 1.24, 95 % CI = 1.05-1.47, P = 0.013; recessive model: OR = 1.22, 95 % CI = 1.05-1.41, P = 0.008, and Cys vs. Ser: OR = 1.11, 95 % CI = 1.02-1.21, P = 0.022), and further stratification analysis showed that the association was stronger in Asians, never smokers, and more-cigarette takers. These results were confirmed by FPRP analysis. Despite some limitations, this meta-analysis provides solid evidence that hOGG1 Ser326Cys polymorphism may contribute to lung cancer risk, particularly for Asian populations, never smokers, and more-cigarette takers. Nevertheless, these findings warrant further validation in single large investigations.