Evaluation of p21,p53 expression and ki-67 proliferative activities in children with helicobacter pylori gastritis

Background: Helicobacter pylori that is generally acquired in childhood and infects the gastric mucosa is charged for many pathobiologic changes that are linked with the pathogenesis of gastrik cancer. Although the majority of studies about the subject have been performed in adults; there are limited number of studies about children that reflects the early period of infection and may be of greater significance.Aim: We aimed to determine the role of H.pylori infection and/or gastritis on several histopathological changes, p53, p21 and cell prolifaretion-associated Ki-67 antigen expression in the gastric mucosa.Methods: We studied 60 patients with a mean age at referral of 7,5±4,5 years. By endoscopic appearance and the evaluation of the gastric antral specimens the patients were studied in three groups which involves the patients without gastritis and gastritis with +/- H.pylori. In order to determine the expression of p53, Ki-67 and p21 in gastric biopsy specimens immunohistochemical stains were performed.Results: The frequency of neutrophil activity which is one of our histopathologic parameters was significantly higher in H.pylori (+) gastritis group than the other two groups. The presence of lymphoid aggregate was more frequent in H.pylori +/- gastritis groups than the non-gastrit group. p53 expression was found significantly higher in H.pylori (+) gastritis group than the non-gastrit group. Ki-67 and p21 expressions were significantly more frequent in the H.pylori (+) gastritis group than the other two groups. When we evaluate the density of H.pylori, as the density of bacteria increases we detected that the expression of p53, p21 and Ki-67 was significantly rised.Conclusion: Expression of the studied precanserous markers in significant amounts in childhood introduces the importance of the early eradication of the bacteria in order to prevent the constitution of gastric cancer in adulthood.Key words: Helicobacter pylori, gastritis, p53, p21, Ki-67, intestinal metaplasia, gastric atrophy