Asociación de los polimorfismos IL-1B-511 e IL-1RN y Helicobacter pylori CagA positivo con cáncer gástrico en una zona de riesgo alto en Colombia / Association of interleukin-1 genetic polymorphism and CagA positive Helicobacter pylori with gastric cancer in Colombia

ABSTRACT

Background: There is an association of interleukin (IL)1B polymorphism with gastric cancer risk. However systematic reviews of the existing evidence have shown that such association varies across populations with different genetic ancestry. Aim: To evaluate the association of IL-1B-511 and IL-1RN polymorphism and Helicobacter pylori IgG antibodies CagA, with gastric cancer in two Colombian cities located in a high risk area for gastric cancer. Material and Methods: A case-control study including 46 gastric cancer cases and 99 controls with non-atrophic gastritis from a high risk zone for gastric cancer. Polymorphism genotyping was carried out by polymerase chain reaction (PCR) and IgG CagA status by ELISA. Results: IgG CagA seropositive individuals had an increased gastric cancer risk (odds ratio (OR) = 11.56; 95 percent confidence intervals (CI) 2.62-50.91 in Tunja and OR = 19.66, 95 percentCI 0.98-395 in Bogotá). IL-1B-511TT carriers in Tunja had increased risk of gastric cancer (OR = 11.31; 95 percentCI 1.20-106.54)), while IL-1RN*2 alelle carriers in Bogotá showed an inverse association with gastric cancer risk (OR = 0.03; 95 percentCI 0.01-0.65). Conclusions: This study adds evidence to the positive association of Helicobacter pylori CagA positive strains with non-cardial gastric cancer etiology. There is a possible heterogeneity in the association of IL-1B gene polymorphism with cancer, in populations of similar ethnic background and settled in the same risk area.