Effects of the Cyclin D1 Polymorphism on Lung Cancer Risk - a Meta-analysis

Background: Cyclin D1 (CCND1) is critical in the transition of the cell cycle from G1 to S phases andunbalanced cell cycle regulation is a hallmark of carcinogenesis. A number of studies conducted to assess theassociation between CCND1 G870A polymorphism and susceptibility to lung cancer have yielded inconsistentand inconclusive results. In the present study, the possible association above was assessed by a meta-analysis.
Methods: Eligible articles were identified for the period up to November 2011. Pooled odds ratios (OR) with95% confidence intervals (95%CI) were appropriately derived from fixed effects or random-effects models.Sensitivity analysis excluding studies whose genotype frequencies in controls significantly deviated from theHardy-Weinberg equilibrium (HWE) was performed.
Results: Ten case-control studies with a total of 10,548subjects were eligible. At the overall analysis the CCND1 870A allele appeared to be associated with elevatedlung cancer risk (for allele model, pooled OR = 1.24, 95% CI: 1.08-1.44, P = 0.004; for homozygous model,pooled OR = 1.45, 95% CI: 1.14-1.84, P = 0.003; for recessive model, pooled OR = 1.29, 95% CI: 1.06-1.58, P= 0.013; for dominant model, pooled OR = 1.33, 95% CI: 1.08-1.65, P = 0.009). Subgroup analyses by ethnicityand sensitivity analysis further pointed to associations, particularly in Asians.
Conclusion: This meta-analysissuggests that the A allele of CCND1 G870A polymorphism confers additional lung cancer risk.