Introduction: Interleukin-6 (IL-6) is a circulating proinflammatory cytokine that fulfills an important role in the survival and proliferation of cancer cells. Overexpression of IL-6, possibly due to the -174G>C and -596G>A polymorphisms in the IL6 gene, has been shown to be related to breast cancer (BC) and a more aggressive course of the disease. Aim: To determine the influence of the -174G>C and -596G>A polymorphisms of the IL6 gene on the circulating levels of IL-6 in BC patients from Jalisco, México. Methodology: Genotyping of the two polymorphisms was carried out on 208 BC patients and 219 healthy controls through polymerase chain reaction-restriction fragment length polymorphism analyses. In addition, the plasma IL-6 concentration levels were measured in the BC patients. Results: There was no significant association between BC and the IL-6 alleles and genotypes (-174G>C, p = 0.276; -596G>A, p = 0.762) under study. Similarly, there were no significant differences in the mean plasma IL-6 concentrations associated with the polymorphisms that were analyzed (-174G>C, p = 0.839; -596G>A, p = 0.848). Conclusions: No evidence was found that the analyzed polymorphisms are associated with the IL-6 expression or concentration in patients suffering from BC from Jalisco, Mexico.
Keywords: IL-6; IL6 polymorphisms; breast cancer.