Insertion/deletion (I/D) in the Angiotensin-converting Enzyme Gene and Breast Cancer Risk: Lack of Association in a Metaanalysis

Purpose: Breast cancer is an important cause of cancer-related death in women. Numerous studies haveevaluated the association between the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme(ACE) gene and breast cancer risk. However, the specific association is still controversial rather than conclusive.Therefore, we performed a meta-analysis of related studies to address this controversy.
Methods: PubMed,EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematicallysearched to identify relevant studies. A meta-analysis was performed to examine the association between theI/D polymorphism in the ACE gene and susceptibility to breast cancer. Odds ratios (ORs) and 95% confidenceintervals (95% CIs) were calculated.
Results: 10 separate studies of 7 included articles with 10,888 subjects onthe relation between the I/D polymorphism in the ACE gene and breast cancer were analyzed by meta-analysis,and our results showed no association between the I/D polymorphism in the ACE gene and breast cancer in totalpopulation and different populations. No publication bias was found in the present study.
Conclusions: The ACEI/D polymorphism may not be associated with breast cancer risk. Further large and well-designed studies areneeded to confirm this conclusion.