Polymorphisms in IL-2 and IL-6R increase serum levels of the respective interleukins in differentiated thyroid cancer

Objectives To investigate polymorphisms of IL-2 and IL-6R genes in patients with differentiated thyroid cancer (DTC), correlating them to previously obtained data on serum levels of IL-2 and IL-6R with DTC. Methods We evaluated the polymorphic inheritance of 300 malignant thyroid nodule patients and 300 healthy controls, including 200 patients with malignant nodules and 100 healthy controls previously investigated by ELISA for serum IL-2 and IL-6R levels. Results The genotypic distribution of IL-2 and IL-6R did not differ between cases and controls. Six haplotypes were generated for IL-6R SNPs, none of the haplotypes showed significance with the risk for thyroid cancer. Significant correlation was observed between all investigated polymorphisms and the serologic levels of the corresponding interleukins. Patients who had the IL-2 gene TT genotype of rs2069762 had higher serum levels of IL-2. Individuals with the CC genotype of rs2228145, the GG genotype of the rs4845622 and the AA genotype of the rs6684439 correlated with a higher serum production of IL-6R. Conclusion We demonstrated that IL-2 SNPs rs2069762, IL-6R rs2228145, IL-6R rs4845622 and IL-6R rs6684439 are associated with differences in the concentrations of the respective interleukins and these concentrations suggesting they may have a clinical utility distinguishing patient with active-disease.