Sousa H.,Laboratorios 4o Piso |
Sousa H.,Portuguese Institute of Oncology of Porto |
Sousa H.,University of Porto |
Breda E.,Portuguese Institute of Oncology of Porto |
And 10 more authors.
Archives of Oral Biology | Year: 2013
Background: Nasopharyngeal carcinoma (NPC) is a rare malignancy in Western countries that is widely associated with the infection by Epstein-Barr virus (EBV). Several studies have showed that a common allele (allele 2) of the 86-bp variable number of tandem repeats (VNTR) polymorphism within intron 2 of the interleukin 1 receptor antagonist (IL-1RN) gene is associated with several disorders, including viral-associated cancers. Methods: We have developed a hospital-based case-control study to characterise the role of the IL-1RN 86-bp VNTR polymorphism in the development of NPC with 112 patients with the disease and 433 healthy individuals from the northern region of Portugal. IL-1RN genotypes were combined according to the number of repeats: allele 2 (A2), the short allele that corresponds to two repeats, and L, the long allele that corresponds to three or more repeats. Results: Our study revealed that 31.2% of NPC patients were IL-1RN A2*A2, compared with 9.7% observed in the control group. The statistical analysis revealed that IL-1RN*A2 homozygosity for the A2 allele was associated with a fourfold increased risk for NPC development (p < 0.001). Additionally, cumulative hazard analysis revealed that estimated median age of onset of NPC is significantly (p < 0.001) different for A2*A2 homozygous versus non-A2*A2 (57.0 vs. 74.0, respectively). Conclusions: This is the first study to evaluate the role of the IL-1RN VNTR in NPC development in Portugal. Our study indicates IL-1RN*A2 homozygosity as a significant risk marker in our population and that it should be further investigated for the potential role in the definition of a susceptibility profile for NPC onset. © 2013 Elsevier Ltd. All rights reserved.