DECREASE IN ORNITHINE DECARBOXYLASE ACTIVITY AFTER ERADICATION OF HELICOBACTER-PYLORI

Objective: Our aim was to determine whether gastric mucosal ODC activi ty is altered after successful eradication of HP. Recent reports have suggested that Helicobacter pylori (HP) infection of the stomach is as sociated with the development of gastric cancer. Gastrointestinal canc ers usually do not arise de novo; a series of mucosal changes leading to neoplastic transformation and degrees of dysplasia are believed to precede the development of cancer. These conditions are associated wit h increased cellular proliferation. Ornithine decarboxylase (ODC) acti vity is induced by factors that stimulate cellular proliferation, and has been shown to be elevated in gastrointestinal neoplasia, including gastric cancer. Methods: Gastric antral and body biopsies were obtain ed from 17 HP-positive patients at endoscopy, for ODC activity and his tology (including Warthin Starry stain) before and 4-6 wk after succes sful triple therapy. Results: Patients included 12 males and five fema les, with a mean age of 55 yr (27-73 yr). Mean ODC activity (in pmol C O2/mg protein/h) was significantly decreased after eradication of HP, compared with pretreatment levels in antral (147 +/- 26 vs. 80 +/- 15) and body mucosa (76 +/- 21 vs. 20 +/- 5) (p < 0.05). Conclusion: Succ essful eradication of HP decreases mucosal proliferative activity, as reflected by decreased ODC activity. We speculate that by decreasing m ucosal proliferative activity, HP eradication may help decrease the su bsequent risk of gastric cancer.