The Interleukin-6 -174 G/C promoter polymorphism is associated with an aggressive breast cancer phenotype in women in Erbil city
Background: To characterize single nucleotide polymorphisms (SNPs) within the promoter region of the -174 of the interleukin-6 (IL-6) gene promoter and to analyze the association of IL-6 SNPs with aggressive breast cancer in women in Kurdistan Region, Northern Iraq. Materials and methods: Genotype frequencies of three SNPs (-174CC, -174GC, -174GC) in the promoter region of the IL-6 gene in 96 women with breast cancer and 96 healthy women were determined using a polymerase chain reaction (PCR), direct sequencing, and alignment. Using an ELISA kit, the frequency of IL-6 blood levels in 96 breast cancer patients and 96 healthy controls were determined and compared with IL-6 genotypes. The IL-6 genotypes were compared to the stages of breast cancer to find the relationship between the genotypes and the severity of the disease. Result: Breast cancer women with the genotype GC of IL-6 had a significantly higher association with high blood IL-6 levels and aggressive breast cancer compared to the other two genotypes, CC and GG of IL-6. The frequency of IL-6 genotypes showed a considerable difference between patients and the healthy control women. The IL-6 CC genotype was the most prevalent among healthy controls. Conclusions: The IL-6 GC genotype is linked to aggressive breast cancer and elevated serum IL-6 levels in breast cancer women from Erbil/Kurdistan Region, Northern Iraq. It's important in the treatment and response to chemotherapy. Additional work is required to confirm our findings in breast cancer and elucidate the practical implications of IL-6–174 promoter polymorphisms in this patient population.