Cyclin D1 G870A polymorphism and lung cancer risk: a meta-analysis

Many studies have investigated the association between Cyclin D1 (CCND1) G870A polymorphism and lung cancer risk, but the impact of CCND G870A polymorphism on lung cancer is unclear owing to the obvious inconsistence among those studies. This study aimed to quantify the strength of association between CCND1 G870A polymorphism and lung cancer risk. We searched the PubMed, Embase, and Wangfang databases for articles on studies relating the CCND1 G870A polymorphism to the risk of lung cancer in humans. We estimated summary odds ratios (ORs) with their confidence intervals (CIs) to assess the association. Meta-analyses of total studies showed that CCND1 G870A polymorphism was associated with lung cancer risk under three genetic models (OR_{A versus G} = 1.13, 95 % CI 1.03–1.24; OR_{AA versus GG} = 1.20, 95 % CI 1.07–1.35; OR_{AA versus AG + GG} = 1.23, 95 % CI 1.02–1.50). Meta-analyses of studies with high quality showed that CCND1 G870A polymorphism was associated with lung cancer risk under two genetic models (OR_{A versus G} = 1.08, 95 % CI 1.02–1.15; OR_{AA versus GG} = 1.17, 95 % CI 1.04–1.32). Subgroup analyses by ethnicity and sensitivity analyses further identified the significant association above. No evidence of publication bias was observed. Meta-analyses of available data show a significant association between the CCND1 G870A polymorphism and lung cancer risk, and CCND1 G870A polymorphic variant A contributes to increased risk of lung cancer.