beta-catenin, an inducer of uncontrolled cell proliferation and migration in malignancies, is localized in the cytoplasm of vascular endothelium during neovascularization after myocardial infarction

beta-catenin is a protein. involved in cell-cell adhesion and proliferation . In neoplastic diseases, defects in the regulation of the cellular beta-ca tenin content and cytoplasmic accumulation of the protein contribute to the uncontrolled cell proliferation and migration, Whether beta-catenin plays a role in the controlled proliferative and migratory responses to Injury, e g, of vascular endothelial cells during neovascularization after myocardial infarction (MI), is not known. In the present study, we examined the local ization of beta-catenin in the infarcted rat heart at different time points after MI. Cytoplasmic beta-catenin was observed in the endothelial cells o f the newly formed and pre-existing blood vessels in the infarct area in th e first week after MI, but not in the uninjured parts of the heart and not at later time points. Adenomatous polyposis coli (APC) protein was also det ected; interaction of APC with beta-catenin. has been reported to be critic al in epithelial tube formation in vitro. Moreover, the expression of dishe velled-1, an upstream regulatory molecule of the cellular beta-catenin cont ent, was observed in vascular endothelial cells in the infarct area. These findings suggest a role for the beta-catenin-APC complex in the proliferati on and migration of vascular endothelial cells during neovascularization of the infarct area.