Abstract
BACKGROUND AND OBJECTIVE: The association between angiotensin-converting enzyme insertion/deletion gene polymorphism and lung cancer susceptibility is still being debated. This meta-analysis was performed to evaluate the relationship between angiotensin-converting enzyme insertion/deletion gene polymorphism and lung cancer risk. METHOD: Association studies were identified from the databases of PubMed and China Biological Medicine Database disc as of June 1, 2015, and eligible investigations were synthesized using meta-analysis method. RESULTS: Ten investigations were identified for the analysis of association between angiotensin-converting enzyme insertion/deletion gene polymorphism and lung cancer risk. There was no a marked association between D allele/DD genotype and lung cancer susceptibility, and II genotype did not play a protective role against lung cancer risk in the overall population (D: odds ratio = 1.05, 95% confidence interval: 0.88-1.26, P = .58; DD: odds ratio = 1.18, 95% confidence interval: 0.82-1.69, P = .38; II: odds ratio = 0.99, 95% confidence interval: 0.77-1.27, P = .93). Furthermore, angiotensin-converting enzyme insertion/deletion gene polymorphism was not associated with lung cancer susceptibility in Asian population and in Caucasians. CONCLUSION: Angiotensin-converting enzyme insertion/deletion gene polymorphism was not associated with lung cancer susceptibility. However, more investigations are required to further clarify the association.