Lack of association among TNF-α gene expression, -308 polymorphism (G > A) and virulence markers of Helicobacter pylori

Author(s):Show less -

Luanna Munhoz Zabaglia ; Mariane Avante Ferraz ; Weendelly Nayara Pereira ; Wilson Aparecido Orcini ; Roger Willian de Labio ; Agostinho Caleman Neto ; Fernanda Wisnieski ; Juliana Garcia de Oliveira ; Marilia de Arruda Cardoso Smith ; Spencer Luiz Marques Payão ; Lucas Trevizani Rasmussen

• Document type: Journal article
• Source: Journal of Venomous Animals and Toxins including Tropical Diseases; v. 21, p. -, 2015.

Abstract

Abstract Background Tumor necrosis factor plays a critical role in the pathogenesis of gastric diseases such as gastric cancer, and an abnormal inflammatory response has frequently been observed in dyspeptic patients. Helicobacter pylori infection can induce a gastric mucosal inflammatory response that may be influenced by -308 (G > A) polymorphisms and gene expression of theTNF-α gene. Methods One hundred and thirty-four gastric biopsy samples were collected from patients of both genders (61♂ and 73♀, mean age 40.3 ± 24.2 years) with gastric symptoms. The -308 (G > A) polymorphism of TNF-α was characterized using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The expression level was measured using real-time PCR, and relative quantification (RQ) was calculated using the comparative CT method (2-ΔΔCT). Results The analysis revealed an increase in TNF-α gene expression in patients with gastritis; on the other hand, no statistical differences were observed in patients with gastric cancer. In addition, no association was found among -308 polymorphism genotypes, virulence markers, or TNF-α gene expression. Conclusions Helicobacter pylori induces a large increase in TNF-α expression in patients with gastritis, regardless of tissue inflammation, but after the tissue becomes neoplastic, the presence of bacteria did not influence expression. These results suggest that the TNF-α pathway may play an important role in the progression from gastritis to gastric cancer (AU)

• FAPESP's process: 13/21224-4 - Genotyping and Gene Expression Analysis of TNF-Alpha in samples from patients with gastric disease: A Possible relationship with Helicobacter pylori.
• Grantee: Luanna Munhoz Zabaglia
• Support type: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/18333-3 - Characterization of virulence factor dupA, of Helicobacter pylori, genotyping and analysis of the expression of genes of tumor necrosis factor and E-cadherin in samples of children and adults with symptoms peptides
• Grantee: Lucas Trevizani Rasmussen
• Support type: Regular Research Grants
• FAPESP's process: 13/21285-3 - Characterization of dupA gene of Helicobacter pylori and gene expression analysis of E-Caderin gene in gastric biopses samples from dyspeptic patients and gastric cancer.
• Grantee: Mariane Avante Ferraz
• Support type: Scholarships in Brazil - Scientific Initiation