Long-term omeprazole and esomeprazole treatment does not significantly increase gastric epithelial cell proliferation and EGFR expression and has no effect on apoptosis and p53 expression

Aims: Proton pump inhibitor (PPI) therapy is widely used in the treatment of patients with reflux oesophagitis. It is known that long-term omeprazole treatment reversibly increases gastric epithelial cell proliferation but there is limited information available about the in vivo changes of apoptosis, p53- and EGFR expression on gastric mucosa during long-term PPI treatment.

Aims: To study the effect of long-term PPI therapy on gastric epithelial cell proliferation, apoptosis, p53- and EGFR expression.

Methods: After informed consent, gastric biopsies of the antrum were taken from 14 and 12 patients with reflux esophagitis prior to and after 6 months of 20mg omeprazole or 40mg esomeprazole therapy. Patients did not take other medications known to affect the gastric mucosa. All patients were H. pylori negative as confirmed by rapid urease test and histology, respectively. Cell proliferation, apoptosis, EGFR and p53 expression were measured by immunohistochemical techniques. At least 600 glandular epithelial cells were encountered and results were expressed as % of total cell counted. P value <0.05 was considered as significant.

Results: Although there was a trend towards increase of cell proliferation and EGFR expression both in omeprazole and esomeprazole treated group, the difference was statistically not significant. Neither apoptosis nor p53 expression were affected. Conclusion: Long-term PPI treatment does not significantly increase gastric epithelial cell proliferation and EGFR expression and has no effect on apoptosis and p53 expression. Six months treatment with PPI is not associated with cell proliferation abnormalities of the gastric antral mucosa.

Supported in part by OTKA Grant No.: T 034345