Iranian

---

Background: The aim of this study was to understand any association between differentiated thyroid carcinoma (DTC) and Ile3434Thr XRCC7 gene polymorphism (GenBank accession number: rs7830743). DTC is the most prevalent thyroid neoplasm, which includes papillary and follicular cell carcinoma. XRCC7 gene encodes a protein that functions in non-homologous end joining DNA repair pathway. Non-synonymous polymorphisms in this gene may alter DNA repair capacity of the cell and change the risk of developing cancers. Methods: DTC patients (n = 173) and cancer free individuals (n = 204) were enrolled in a case-control study. The Ile3434Thr polymorphic alleles were discriminated by using amplification refractory mutation system-PCR method. The frequencies of this single nucleotide polymorphism in case and control groups were compared. Also, risk ratio for developing DTC in dichotomized genotypes was estimated by multivariate logistic regression analysis. Results: Dichotomized genotypes into those with and without the 3434Thr allele showed that this allele was associated with DTC (OR [odd ratio]: 1.89, 95% confidence interval (CI) = 1.29-2.79, P<0.001). Also, TC genotype was significantly associated with increased risk of DTC (OR: 2.42, 95% CI = 1.55-3.81, P = 0.0001) in individuals carrying this genotype. Conclusion: Allele 3434Thr in XRCC7 gene might be associated with differentiated thyroid cancer risk. Further studies with larger samples are needed to verify these initial findings.

---

Background: Gastric cancer arises, mainly, on an inflammatory background. Helicobacter pylori neutrophil activating (HP-NAP) protein functions as a potent pro-inflammatory mediator.  Similarly, IL-4 plays a critical role in the inflammation pathway, the levels of which are altered by C to T transition at position -590 in its promoter region. Here, we have aimed to assess the risk of gastritis and gastric cancer in the co-presence of these two inflammation modulating mediators. Methods: Gastritis (n=58) and gastric cancer (n=31) patients were evaluated and compared with H. pylori-positive asymptomatic controls (n=46), for serum antibodies against recombinant HP-NAP and IL-4 C-590T single nucleotide polymorphism using immunoblotting and PCR-RFLP, respectively. Multivariable logistic regression, adjusting for age, gender and ethnicity, was used for data analysis. Results: In terms of susceptibility to gastritis, seropositivity to HP-NAP projected a risk impact of 4.62 fold (OR=4.62, 95% CI=1.50-14.22), which when present in IL-4 -590 T carriers augmented the risk up to 9.7 fold (OR=9.70, 95% CI=2.06-45.69). A similar pattern, but of a stronger magnitude, occurred for the risk of gastric cancer, which was estimated at 9.07 fold (OR=9.07, 95% CI=1.99-42.0) for HP-NAP-seropositive subjects and was drastically amplified (OR=33.64, 95% CI=2.06-548.68), when double-positive (HP-NAP seropositive/IL-4 -590 T carrier) subjects were examined against double negatives (HP-NAP seronegative/IL-4 -590 CC). Conclusion: Our preliminary data indicate that serum antibodies against HP-NAP represent a state of risk, which is further exacerbated in IL-4 -590 T carriers. These biomarkers, if validated in larger prospective studies, can be used to screen for gastric cancer susceptibility.