67 Background: Nasopharyngeal Carcinoma(NPC) is an Epstein-Barr virus(EBV) associated malignancy with remarkable ethnic and geographical distribution. The EBV oncoprotein latent membrane protein 1 (LMP1) is the primary oncogene of EBV infection through the its signaling cascade and its connections to other pathways including NF-κB, TGF-β and JNK signaling, which plays an important role in the pathogenesis of NPC. In GWASs (Genome-wide association studies) associations these pathways were also identified. Single nucleotide polymorphisms (SNPs) in the regulatory regions may regulate the expression of genes in these pathways, or affect the function of the coded protein. Methods: Altogether 149 SNPs were covered by the 15 SNPs in the TRAF2, TRAF3, NFKBIA, MAP2K4, and CHUK genes were genotyped in a hospital-based case-control study of 350 NPC cases and 587 healthy controls from the Chinese Han. The observed genotype frequencies in the controls were tested for Hardy–Weinberg equilibrium (HWE) using the chi-square test. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between genotypes and NPC risk and tumor characteristics were calculated by logistic regression, and they were adjusted for multiple testing using the SNP spectral deposition (SNPSpD) approach for multilocus analyses. Results: We found one NFKBIA SNP was associated with NPC risk after adjustment for multiple comparisons. Minor allele carriers of the NFKBIA had an increased risk of NPC (P 0.05). The analyses were adjusted for age and gender. For a polymorphism with a variant allele frequency between 10 %and 50%, the study had greater than 90% power to detect an OR of 1.50 at a significance level of 0.05 (PS—software for power and sample size calculation, http://biostat.mc.vanderbilt.edu/twiki/bin/view/Main/PowerSampleSize). The other genotyped SNPs that we found were not associated with NPC risk. Conclusions: Our data suggests that genetic variation especially in the NFKBIA maybe a useful biomarker for NPC screening and further studies are warranted.
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