Associations between promoter polymorphism -106A/G of interleukin-11 receptor alpha and papillary thyroid cancer in Korean population

BackgroundThe interleukin11 (IL11) and IL11 receptor alpha (IL11RA) are involved in cellular growth, differentiation, invasiveness, and tumor progression in several tumors. We investigated whether coding single nucleotide polymorphisms (cSNPs) of IL11 and promoter SNP IL11RA would contribute to the development of papillary thyroid cancer (PTC). We also assessed the relationships between IL11 and IL11RA SNPs and the clinicopathologic characteristics of PTC.MethodsOne coding SNP, designated as rs1126757, Ala82Ala, in IL11 and one promoter SNP, designated as rs1061758, −106A/G, in IL11RA were genotyped using direct sequencing in 94 patents with PTC and 213 patients without PTC (controls). Genetic data were analyzed using commercially available software. The patients with PTC were dichotomized and compared with respect to clinicopathologic characteristics of PTC.ResultsWe found an association between PTC and the coding SNP(rs1061758) in IL11RA (codominant model 1 [G/G vs A/G], odds ratio [OR] = 2.91, 95% confidence interval [CI], 1.44–5.89; P = .003; codominant model 2 [G/G vs A/A], OR = 2.95, 95% CI, 1.30–6.72; P = .01; and dominant model, OR = 2.92, 95% CI, 1.47–5.80; P = .002). Moreover, SNP rs1061758 in IL11RA was associated with the multifocality of PTC (codominant model 2 [A/A vs G/G], OR = 9.56, 95% CI, 1.77–51.69; P = .009; and recessive model, OR = 7.22, 95% CI, 1.72–30.3; P = .007). Genotype and allele analyses of SNP variant rs1126757 in IL11 revealed no statistically significant differences between patients with PTC and controls.ConclusionOur results suggest that an IL11RA promoter polymorphism — rs1061758 — may be associated with the risk of PTC in the Korean population. In addition, rs1061758 might be related to the multifocality of PTC.