In this study the EA.hy 926 endothelial cell line--simulating endothelial cells--was treated with imatinib in order to define a possible anti-angiogenic role for imatinib. Dose and time response experiments were performed. Cell morphology was studied, while migration efficiency, intercellular permeability and VE-cadherin expression were assayed, both in the presence and in the absence of imatinib. Imatinib-induced EA.hy 926 cell apoptosis was also examined. Results showed that imatinib reduced the endothelial cell population, changed cell monolayer morphology and reduced cell-to-cell cohesiveness. Migration efficiency was significantly decreased while intercellular permeability was 2.76-fold increased in the presence of imatinib. Indirect immunofluorescence microscopy showed nearly complete down-regulation of VE cadherin in imatinib-treated cells. Furthermore, apoptotic activity was detected in imatinib-treated cells. Altogether our results support an antiangiogenic profile for imatinib that possibly contributes to its therapeutic potential.