CCND1 G870A polymorphism contributes to the risk of esophageal cancer: An updated systematic review and cumulative meta-analysis

The common functional cyclin D1 (CCND1) G870A polymorphism may influence the risk of esophageal cancer. However, the conclusions of previous studies have been inconsistent for the association between the CCND1 G870A polymorphism and esophageal cancer risk. A meta-analysis of 11 published case-control studies was performed, including 2,111 patients with esophageal cancer and 3,232 controls, to investigate the association between the CCND1 G870A polymorphism and esophageal cancer risk. The odds ratio (OR) with a 95% confidence interval (CI) was applied to assess the association between the CCND1 G870A polymorphism and esophageal cancer risk. A significant association between the CCND1 G870A polymorphism and esophageal cancer risk was observed for the allele contrast (A vs. G: OR, 1.23; 95% CI, 1.02-1.48; P= 0.029), codominant (AA vs. GG: OR, 1.58; 95% CI; 1.06-2.35; P= 0.024) and recessive models (AA vs. GG + GA: OR, 1.33, 95% CI, 1.03-1.73; P= 0.030). However, in the stratified analysis by ethnicity, study design and pathology, there was no significant association detected in these genetic models. In conclusion, results of the meta- analy-sis suggested that the CCND1 G870A polymorphism is a potential risk factor in the development of esophageal cancer.