Document Type : Research Articles
Helicobacter Pylori and Gastric Pathologies Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco.
Biology and Health Laboratory, Faculty of Sciences Ben M’sik, University Hassan II, Casablanca, Morocco
Pathogenesis of Helicobacter Laboratory, Institut Pasteur, Paris, France.
Gastroenterology Department, Ibn Rochd University Hospital Center, Casablanca, Morocco.
Department of Radiotherapy Oncology, Ibn Rochd University Hospital Center, Casablanca, Morocco.
Histo-Cytopathology Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco.
Objective: Helicobacter pylori (H. pylori) induces the production of tumor necrosis factor-alpha (TNF-α), which is closely related to a gastric epithelial injury. TNF-α gene polymorphism and TNF-α serum levels are associated with various malignant conditions. Identification of the ideal marker for gastric cancer (GC) is still the leading aim of several trials. Physio-pathological considerations of GC led us to investigate the association of two TNF-α promoter polymorphisms (-308G>A and -238G>A), and TNF-α serum levels with the susceptibility to gastric precancerous (PL) and GC. Methods: Patients suffering from gastric lesions (65 chronic gastritis, 50 PL, 40 GC) related to H. pylori infection , and 63 healthy controls (HC) were involved in this study. Individuals are genotyped by TNF-α gene promoter sequencing and TNF-α serum levels are measured by ELISA quantitative method. Results: Regarding TNF-α-308 G/A locus, we noticed higher risk for GC (OR=4.3, CI 1.5-11.9, p-value=0.005) and PL (OR=3.4, CI 1.2-9.2, p-value=0.01) for individuals with AA/GA genotypes compared to GG genotype. Concerning TNF-α-238 G/A locus, we noticed higher risk for GC (OR=5.9, CI 1.2-27.5, p-value=0.01) and PL (OR=4.8, CI 1.3-18, p-value=0.01) for individuals with GG genotype compared to AA/GA genotypes. We noticed that TNF-α serum levels have been increased together with gastric lesions severity. Moreover, TNF-α-308 and TNF-α-238 A alleles seemed to, respectively, upregulate and downregulate TNF-α serum levels. Conclusion: The TNF-α -308 A allele has a promotive effect for GC progression, whereas the TNF-α -238 A allele has a protective function against GC progression. High levels of TNF-α seemed to be associated with the aggressiveness of gastric lesions. TNF-α gene polymorphisms and TNF-α serum levels might be helpful to select those patients who are at high risk for GC.