Alexandra M. Santos

Linkage of TP53 codon 72 pro/pro genotype as predictive factor for nasopharyngeal carcinoma development.

Genetic predisposition has been suggested as a cofactor for cancer aetiology and a polymorphism in TP53 codon 72 has been associated as a susceptibility factor for several cancers. Nasopharyngeal carcinoma is a rare neoplasia in western civilizations and genetic predisposition might play an important role in its development. We evaluated the linkage of the polymorphic variants (Arg/Pro) on TP53 codon 72 with nasopharyngeal cancer development in a case–control study with 392 individuals from a northern Portuguese population, including 107 patients with nasopharyngeal carcinoma and 285 healthy controls. This study revealed a three-fold risk for carriers of Pro/Pro genotype either against carriers of Arg/Arg (OR=2.62; 95% CI=1.10–6.30; P=0.016) or total Arg carriers (OR=2.67; 95% CI=1.21–5.90; P=0.012). Moreover, step-wise logistic regression analysis identified Pro/Pro genotype (OR=3.1; 95% CI=1.3–7.3; P=0.009), age >49 at diagnosis (OR=2.5; 95% CI=1.6–4.0; P<0.001) and male gender (OR=2.7; 95% CI=1.6–4.4; P<0.001) as predictive factors for the development of nasopharyngeal carcinoma. These results confirm the data from Asiatic populations suggesting that Pro/Pro genotype represents a stable risk factor for nasopharyngeal carcinoma development in Portugal and that TP53 codon 72 polymorphism can contribute as a genetic susceptibility marker, providing additional information to improve the knowledge about nasopharyngeal carcinoma aetiology.

Genetic Risk Markers for Nasopharyngeal Carcinoma in Portugal: Tumor Necrosis Factor Alpha −308G >A Polymorphism

The tumor necrosis factor-alpha (TNF-α) is a strong proinflammatory cytokine produced by the activated macrophages in the immune response to viral infections. A common polymorphism on the promoter region of TNFA gene (-308G >A) has been associated with different susceptibilities to the development of several diseases including viral-associated neoplasias. Data suggest that the A allele has been associated with higher levels of TNF-α and, therefore, leads to increased risk of cancer development. We have performed a case-control study considering the role of the -308G >A polymorphism in 750 individuals from the northern region of Portugal, including 123 patients with nasopharyngeal carcinoma (NPC) and 627 healthy individuals. Our study revealed an increased frequency of the -308A TNFA allele in patients with NPC. The statistical analysis for recessive model revealed that -308AA genotype is associated with increased risk for the development of NPC (odds ratio = 2.46; 95% confidence interval, 0.98-6.17; p = 0.047); moreover, this effect was stronger in undifferentiated types, which are virtually 100% caused by the Epstein-Barr virus (odds ratio = 2.75; 95% confidence interval, 1.09-6.90; p = 0.025). These results reveal that in our population -308 TNFA AA genotype can represent a risk marker for NPC development and contributes for the definition of genetic susceptibility profiles for individuals at risk of development of a viral infection and associated neoplasia.

The p53 R72P polymorphism does not influence cervical cancer development in a portuguese population: A study in exfoliated cervical cells

The interaction between the E6 protein of the high‐risk human papillomaviruses (HPVs) with p53 seems to be crucial in cervical carcinogenesis. The presence of Arg/Arg genotype at codon 72 of TP53 gene was characterized as a risk factor in development of cervical cancer. However, the role of this polymorphism remains controversial and some authors suggested that the origin of DNA (blood or exfoliated cervical cells) might influence these results. This study analyzed the effect of the p53 codon 72 polymorphism (R72P) in exfoliated cervical cells of women from the northern region of Portugal using two methodologies: allele‐specific polymerase chain reaction and real‐time polymerase chain reaction. We studied 700 cervical exfoliated cells which showed: 334 cases from women without cervical cancer or cervical lesion (N), 114 low‐grade squamous intraepithelial lesions (LSIL), 107 high‐grade squamous intraepithelial lesions (HSIL), 20 invasive cervical cancers (ICC) and 125 atypical squamous cells of unknown significance (ASCUS). No statistically significant differences between cases and controls were found, regarding the influence of the R72P polymorphism with cytological classification, high risk‐HPV infection and HPV16 presence (P = 0.336, P = 0.945, and P = 0.964, respectively). Also, the influence of this polymorphism in the median age of onset for LSIL, HSIL, and ICC was not statistically significant (P = 0.674, P = 0.810, and P = 0.928, respectively). Therefore, the hypothesis that women with Arg/Arg genotype have an increased risk of developing cervical cancer failed to be proven in this study. Moreover, our study reveals that results using exfoliated cervical cells are reliable as compared with studies on blood. J. Med. Virol. 80:424–429, 2008.

Tumour necrosis factor alpha 308 G/A is a risk marker for the progression from high-grade lesions to invasive cervical cancer

Tumour necrosis factor alpha (TNF-α) is a strong pro-inflammatory cytokine with important functions on immune response to viral infections. A single nucleotide polymorphism on the −308 position of the promoter region of TNFA gene characterised by a G > A transition has been associated with different TNF-α levels and therefore with differential susceptibility for the development several diseases. A cross-sectional case–control study was performed with 509 women with cancer from the northern region of Portugal, including 205 healthy women and 337 women with different cervical lesions including invasive cervical. The −308G > A polymorphism genotyping was performed with TaqMan® SNP Genotyping Assay and studied for its association with cervical cancer development. This study showed increased frequency of the −308A allele in women with any cervical lesions. Statistical analysis revealed that −308A carriers are associated with an almost 2-fold increased risk for invasive cervical cancer development (p = 0.005; odds ratio (OR) = 1.87). Similar results were found when comparing the risk of progression between preinvasive lesions and invasive cervical cancer development (p = 0.002; OR = 2.41). Our results reveal that −308 TNFA AA individuals are at increased risk of invasive cervical cancer development and more important, that the risk is significantly increased for the progression from premalignant lesion to invasive cancer. Considering previous data and this study, this polymorphism confirms to be a significant marker in our population.

IL-1RN VNTR polymorphism as a susceptibility marker for nasopharyngeal carcinoma in Portugal

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.

P017: P53 Polymorphism: Susceptibility to Nasopharyngeal Cancer

otolaryngology as synthetic injectable fillers. Teflon uses include the treatment of vocal cord paralysis, velopharyngeal insufficiency, and patulous eustachian tube. Silicone has been used extensively in soft tissue augmentation. However, both have a variety of side effects, including granuloma formation. These synthetic injectable fillers demonstrate marked FDG accumulation on PET/CT, which can be misinterpreted as a neoplasm. Knowledge of the radiographic characteristics of Teflon and silicone, as well as awareness of the clinical history are important in providing an accurate diagnosis and to prevent unnecessary interventions.