Study of the regulatory promoter polymorphism (-938C>A) of B-cell lymphoma 2 gene in breast cancer patients of Mazandaran province in Northern Iran.

Background: The incidence rate of breast cancer has been dramatically increasing since the last decade in Iran, and it is now one of the most common female malignant tumors. B-cell lymphoma 2 (BCL2) family is the most important regulator of apoptosis, and -938C>A single nucleotide polymorphism (SNP) of gene promoter has been demonstrated to influence breast cancer susceptibility. In this research, we study the effect of -938C>A allelic variants on breast cancer risk in Mazandaran province at the North of Iran.

Materials And Methods: This analysis performed on 120 breast cancer patients who underwent surgery in some referenced hospitals at Mazandaran province along with 130 healthy individuals as a control. DNA extracted from peripheral blood samples was applied in polymerase chain reaction-single-strand conformation polymorphism analysis to determine -938C>A genotype. The association of the -938C>A genotype and breast cancer risk as well as clinicopathological characters were analyzed by logistic regression method.

Results: Results showed that genotype frequency of AA, AC, and CC genotypes was 10%, 62%, and 28% for case and 28%, 50%, and 22% in control group, respectively. In the logistic regression model, - 938C/A variant genotype AA was associated with a decreased risk of breast cancer ( = 0.041) by 0.31-fold (odds ratio = 0.31, confidence interval = 0.091-0.909) compared to CC genotype. However, no significant association found between -938C>A genotype and clinicopathological characters.

Conclusion: The study showed that AA genotype of BCL2 gene (-938C>A) is associated with decreased susceptibility to breast cancer. Hence, investigating the -938C>A SNP of BCL2 gene promoter could be an appropriate molecular marker to determine individual sensitivity to breast cancer.