Aberrant Eph B/ephrin-B expression in experimental gastric lesions and tumor cells

AIM: To determine whether the expression profiles of Eph B receptor and ephrin-B ligand can be used as markers for dysplastic/oncogenic transformation in gastric mucosa.METHODS: The protein expression and localization ofEph B and ephrin-B in normal, ulcerated regenerating, and dysplastic gastric mucosa were examined in a rat experimental model by immunolabeling, and m RNA expression was assessed in four human gastric carcinoma cell lines by reverse transcription-polymerase chain reaction.RESULTS: Ephrin-B- and Eph B-expressing regions were divided along the pit-gland axis in normal gastric units. Eph B2 was transiently upregulated in the experimental ulcer, and its expression domain extended to gastric pits and/or the luminal surface where ephrin-B-expressing pit cells reside. Eph B2, B3, and B4 and ephrin-B1 were coexpressed in the experimental gastric dysplasia, and more than one ligand-receptor pair was highly expressed in each of the gastric carcinoma cell lines.CONCLUSION: Robust and stable coexpression of Eph B and ephrin-B is a feature common to experimentally induced gastric dysplasia and human gastric carcinoma cell lines as compared to normal gastric and ulcerated regenerating epithelia. Thus, Eph B/ephrin-B may be a useful marker combination for dysplastic/oncogenic transformation in gastric cancer.