Mapping Neovascularization and Antineovascularization Therapy
The switch of tumors from avascular to the vascular phase and the onset of tumor angiogenesis mark a critical checkpoint in tumor progression. Avascular tumor dormancy can sometimes extend over many years, while upon vascularization, tumors show increased invasiveness, elevated metastatic potential and significantly worse prognosis (Weidner and Folkman, 1996). Regulation of the transition to the vascular phase depends on the balance between the production of promoters and inhibitors of angiogenesis (Hanahan and Folkman, 1996). The goal of our work was to define physiological scenarios which perturb this balance and can thus drive angiogenesis to previously dormant tumors. Such mechanisms that promote angiogenesis may explain epidemiological observations regarding age specific probabilities of certain tumors, environmental effects and the effects of trauma on tumor growth. In order to follow angiogenesis quantitatively, we developed an experimental system that relies on detection of vessel density by magnetic resonance imaging (MRI).
KeywordsVascular Endothelial Growth Factor Expression Angiogenic Growth Factor Angiogenic Switch Multicellular Spheroid Multicellular Tumor Spheroid
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