Genetic Polymorphisms of IL-1B-511, IL-1RN, IL-10 Interleukins, Tumor Necrosis α-308 and Positive Helicobacter pylori CagA Infection in Gastric Cancer and Duodenal Ulcer in Different Populations in Colombia
Keywords:
Interleukins 1B, 10, tumor necrosis factor-alpha, Helicobacter pylori, cagA protein, stomach neoplasm, duodenal ulcerAbstract
Objective: To determine the association between the IL-1B-511, IL-1RN, TNF-α-308, IL-10-819 and IL-101082 polymorphisms and positive Heliocobacter pylori CagA infection in a group of patients with gastric cancer and duodenal ulcer in different populations in Colombia.
Methods: A case-control study was performed on 341 patients: those with non-atrophic gastritis, 194; with gastric cancer, 58; duodenal ulcer with preneoplastic lesion, 54; and with duodenal ulcer, 35. The genotyping of polymorphisms was done with allelic discrimination using PCR in real time, and that for IL-1RN with conventional PCR and agarose electrophoresis. Helicobacter pylori CagA infection was ascertained with ELISA. Logistic regression was used in statistical analysis.
Results: Being a carrier of genotype IL-1B-511TT (OR=4.69; CI 95% 1.22-18.09) and being positive for Helicobacter pylori CagA infection (OR=4.43; CI 95% 1.72-11.4) are associated with gastric cancer. Positive Helicobacter pylori CagA infection (OR=4.39; CI 95% 1.82-10.59) is associated with the presence of duodenal ulcer with preneoplastic lesions, being a carrier of genotype IL-1B-511CT is associated with duodenal ulcer (OR=0.30; CI 95% 0.10-0.91).
Conclusion: The results suggest that pro-inflammatory response and virulent bacterial genetics are factors related to the different outcomes brought about by Helicobacter pylori infection in the population studied; that is, the IL-1B-511 polymorphism is a factor related to gastric cancer and duodenal ulcer, and positive Helicobacter pylori CagA infection is a factor associated with gastric cancer and duodenal ulcer with preneoplastic lesions.
Author Biographies
Teresa Martínez, Instituto Nacional de Cancerología
Grupo de Investigación Epidemiológica del Cáncer, Instituto Nacional de Cancerología, Bogotá D.C., Colombia
Gustavo Hernández, Instituto Nacional de Cancerología
Grupo de Investigación Epidemiológica del Cáncer, Instituto Nacional de Cancerología, Bogotá D.C., Colombia
María M. Bravo, Instituto Nacional de Cancerología
Grupo de Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá D.C., Colombia
Esperanza Trujillo, Instituto Nacional de Cancerología
Grupo de Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá D.C., Colombia
Andrés Quiroga, Instituto Nacional de Cancerología
Grupo de Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá D.C., Colombia
Juan C. Robayo, Fundación Santa Fe
Departamento de Gastroenterología, Fundación Santa Fe, Bogotá D. C., Colombia
Jesús Pérez, Clínica General del Norte
Grupo de investigación, Clínica General del Norte, Barranquilla, Colombia
Juan C. Bravo, Fundación Valle del Lili
Departamento de Patología, Fundación Valle del Lili, Cali, Valle, Colombia
Margarita Camorlinga, Instituto Mexicano de Seguros Sociales
Hospital de Pediatría CMN Siglo XXI, Instituto Mexicano de Seguros Sociales, Ciudad de México, México
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