Impact of bacterial eradication on the cell proliferation and p53 protein accumulation in Helicobacter pylori-associated gastritis

Background: This study investigates the cell proliferation and the expressi on of p53 protein in Helicobacter pylori (H. pylori)-associated gastritis a nd assesses the effect of bacterial eradication on these epithelial factors . Material and Methods: Seventy-nine patients with H. pylori-associated gas ritis were randomized into the control group (n=38) and anti-H. pylori grou p (n=41). Each patient received endoscopic examinations with gastric biopsy before and 8 weeks after the treatment. The specimens from gastric antrum were immmnostained for monoclonal antibodies against the proliferating cell nuclear antigen (PCNA) and p53 protein. Results: In the control group, the total labeling index (L.I) of PCNA and the positive index (P.I.) of p53 in the whole foveolar epithelium were unchanged after treatment. In the anti- H. pylori group, 35 of 41 cases (85.3%) achieved eradication of H. pylori. Amongst the H. pylori-eradicated cases, the total L.I. of PCNA in the whole foveolar epithelium did not meaningfully alter after H. pylori elimination (p>0.05). However, a significant reduction of L.I. was observed in the mid dle compartments of the gastric pits (before vs, after treatment: 14.0 vs. 7.3, p<0.05). With regard to the p53 expression, the P.I.s were significant ly decreased in the whole foveolar epithelium (before vs, after treatment: 0.57 vs. 0.17, p<0.05) and in each compartment of the gastric pits (before vs, after treatment: [upper compartment]: 0.34 vs. 0.15, p<0.05; (middle co mpartment]: 0.67 vs. 0.23, p<0.05; [lower compartment]: 0.71 vs.0.20 p<0.05 ) after eradication of H. pylori. Conclusions: Bacterial eradication revers es the hyperproliferating status of the foveolar epithelium in patients wit h H. pylori gastritis and leads to a decrease in p53 accumulation in the ep ithelial cells.