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Background Host genetic susceptibility markers in immune response associated genes may contribute to identify individuals with high risk of developing viral infection and viral-associated cancers. We aimed to characterize different polymorphisms in immune response associated genes and evaluate its association with nasopharyngeal carcinoma (NPC) development. Methods We have developed a hospital-based case-control study selecting 134 patients with NPC (cases) and 732 healthy individuals (controls) from the Northern Region of Portugal. Eight single nucleotide polymorphisms (SNP) were selected: −56C > T IFNGR1 (rs2234711), +4854G > T IL1A (rs17561), +3954C > T IL1B (rs1143634), +1902A > G IL4RA (rs1801275), −1082G > A IL10 (rs1800896), +2018T > C IL1RN (rs419598), HLA-A locus A > T (rs2530388), HCGA9 locus A > T (rs6457110). All polymorphisms were analysed by real-time methodology using TaqMan ® SNP Genotyping Assays. Results The overall analysis revealed no statistical significant differences between genotypes distributions in all of studied polymorphisms ( p > 0.05). However, the results for HCGA9 rs6457110 polymorphism showed a tendency for an increased risk of NPC development among TT carriers with an almost of 2-fold increased risk (OR = 1.86; 95%CI 1.00–3.65). Conclusions This is the first study to characterize these polymorphisms in NPC patients in Portugal. Our study indicates that HCGA9 rs6457110 polymorphism might represent a risk marker for NPC development in our population and that other SNPs should be further studied in larger populations to clarify the evidences. This data reinforces the need for more studies, especially in NPC low-prevalent populations. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

The incidence of nasopharyngeal carcinoma (NPC) varies worldwide, with higher rates in southern Asia, intermediate rates in Mediterranean basin countries as well as in Greenland and Alaska populations, and low rates in most of the western countries. The percentage of NPC types seems to vary according to the WHO classification. Portugal is also a Mediterranean basin country. The NPC patterns in Portuguese population is comparatively analyzed with a review of the related literature, concerning the overall incidence, male/female ratio, age of incidence, WHO type frequency, Epstein–Barr virus relationship and genetic susceptibility. The particular findings in the Portuguese population can be discussed in the light of genetic background and close relationships with potential exogenous oncogenic factors. [ABSTRACT FROM AUTHOR]

Introduction - The widespread use of formaldehyde is mainly due to its high reactivity, lack of colour, purity in a commercial format, and also low cost. These characteristics put it among the 25 most abundant chemicals produced in the world. IARC, since 2006, classify formaldehyde in Group 1 (carcinogen) based on evidence that exposure to formaldehyde can cause nasopharyngeal cancer in humans. It was developed an exploratory study with the purpose of obtaining information about the occupational exposure reality to formaldehyde in Portugal. Methodology - Several formaldehyde concentrations measurements were performed in 7 industrial units and in an anatomy and pathology laboratory. Environmental measurements were performed using Photo Ionization Detection (PID) equipment. Results - The anatomy and pathology laboratory have the highest concentration value recorded and larger than reference limit (0.3 ppm). Also, in 2 of 7 industrial units studied were recorded maximum concentration values above 0,3 ppm. Conclusions - The anatomy and pathology laboratory was the occupational setting where formaldehyde occupational exposure was more critics. The methodology used for environmental monitoring seems appropriate to the study objectives and related to the chemical agent mode of action. [ABSTRACT FROM AUTHOR]