Divisive influence of interleukin-1 receptor antagonist polymorphisms in melanoma patients

OBJECTIVE The interleukin-1 receptor antagonist (IL-1RA) contributes to tumor survival and progression in multiple cancer entities. IL-1RA polymorphisms influence IL-1RA expression patterns and function. A known polymorphism was correlated with clinical outcomes in melanoma patients with particularly aggressive disease. METHODS DNA of 343 controls and 97 melanoma patients with poor prognostic indicators (time from diagnosis to death, nodal status, metastasis) was analyzed for a variable number of tandem repeat polymorphisms (VNTR) of the IL-1RA gene. Five alleles containing two (allele 2), three (allele 4), four (allele 1), five (allele 3) or six (allele 5) 86-bp repeats were targeted via PCR amplification. RESULTS Genotype 1/2 is less common in the melanoma patient group vs. the control (28.8% vs. 39.6%; p = 0.06). Significant was the stage of the melanoma in order to predict the survivability (p = 0.008). The 1/1 and 1/2 genotype appeared to have lower hazards ratios than the 2/2 genotype (p > 0.05). CONCLUSIONS Compared to the general population, the distribution of alleles coding for IL-1RA is different in melanoma patients. This alteration and the potential impact on tumor protein function and systemic inflammatory response may warrant further investigation.