Aim: To investigate beta-catenin expression in patients with intestinal metaplasia, and to look for a possible relationship between beta-catenin expression and either epithelial proliferation values or Helicobacter pylori (H pylori) infection.
Methods: Twenty patients with complete type intestinal metaplasia were studied. beta-Catenin expression and epithelial cell proliferation in antral mucosa were assessed using an immunohistochemical analysis. H pylori infection was detected by histology and a rapid urease test.
Results: Reduced beta-catenin expression on the surface of metaplastic cells was detected in 13 (65%) out of 20 patients. Moreover, in eight (40%) patients intranuclear expression of beta-catenin was found. When patients were analyzed according to H pylori infection, the prevalence of both beta-catenin reduction at the cell surface and its intranuclear localization did not significantly differ between infected and uninfected patients. Cell proliferation was higher in patients with intranuclear beta-catenin expression as compared to the remaining patients, although the difference failed to reach the statistical significance (36+/-8.9 vs 27.2+/-11.4, P = 0.06). On the contrary, a similar cell proliferation value was observed between patients with reduced expression of beta-catenin on cell surface and those with a normal expression (28.1+/-11.8 vs 26.1+/-8.8, P = 0.7). H pylori infection significantly increased cell proliferation (33.3+/-10.2% vs 24.6+/-7.4%, respectively, P = 0.04).
Conclusion: Both cell surface reduction and intranuclear accumulation of beta-catenin were detected in intestinal metaplasia. The intranuclear localization of beta-catenin increases cell proliferation. H pylori infection does not seem to play a direct role in beta-catenin alterations, whilst it significantly increases cell proliferation.