RESUMO
<p><b>OBJECTIVE</b>To investigated the association between interleukin-10(IL-10)-1082/-819/-592 promoter polymorphism, plasma IL-10 levels and risk of vocal leukoplakia.</p><p><b>METHODS</b>A case-control study of 61 patients with vocal cords leukoplakia and 119 healthy subjects were performed. Genotypes for the IL-10 gene (IL-10 -1082 G/A, -819 C/T and -592 C/A) were determined using pyrosequencing and plasma IL-10 levels were analyzed by ELISA.</p><p><b>RESULTS</b>Smoking and alcohol consumption increased the risk of vocal leukoplakia (OR = 4.73, 95%CI:2.4-9.1;OR = 5.70, 95%CI:2.9-11.2, P < 0.01) . Patients with vocal cord leukoplakia had significantly higher frequencies of AC at -592 and -819 (OR = 1.93, 95%CI:0.97-3.81, P = 0.05) and AG at -1082(OR = 2.14, 95%CI:0.87-5.27, P = 0.092) than control. Vocal leukoplakia patients had higher concentration of plasma IL-10 (21.6 ± 0.5) pg/ml (X(-) ± s) than controls (19.0 ± 1.1)pg/ml(t = 2.08, P = 0.043) and the haplotype containing the G allele was associated with higher plasma IL-10 concentrations (24.3 ± 5.7) pg/ml compared with the ATA haplotype(19.9 ± 4.7) pg/ml (t = -2.64, P = 0.008).</p><p><b>CONCLUSIONS</b>IL-10-1082/-819/-592 promoter polymorphism and high concentration of plasma IL-10 are associated with vocal cord leukoplakia, and the concentration of plasma IL-10 is associated with the genotypes of IL-10 promoter polymorphism.</p>