Interleukin-10 Promoter Polymorphisms and Breast Cancer Risk in Iranian Women

Background: IL-10 is an anti-inflammatory cytokine which is involved in tumorigenesis. Over production of IL-10 and elevated number of IL-10 generating mononuclear cells in breast tumor tissue has already been shown. Objective: To determine the association of IL-10 promoter polymorphisms with increased risk of breast cancer and its association with breast cancer prognostic factors. Methods: Peripheral blood samples from 275 female breast cancer patients and 320 cancer free controls were used to detect three single nucleotide polymorphisms in IL-10 promoter region ( -1082, -819, -592 ) by PCR method. Results: The frequency of genotypes and alleles of three mentioned regions of IL-10 promoter and their haplotypes (GCC, ATA, and ACC) showed no statistically significant difference between patients and controls. In the case of prognostic factors, progesterone receptor (PR) status exhibited significant relation with -1082 genotypes (P=0.03) and haplotypes (P=0.02). -1082 AA genotype was associated with negative PR expression whereas AG and GG genotypes of this site were positively associated with PR expression. Similarly GCC haplotype correlated with positive PR expression and ATA and ACC with negative PR expression. Conclusion: The data of this study showed that IL-10 promoter gene polymorphisms may not be considered as one of the risk factors for breast cancer in Iranian patients.