Patients undergo blood sample collection periodically for translational studies. Samples are analyzed for circulating endothelial cells and endothelial progenitor cells via flow cytometry; angiogenic activity of serum/plasma in angiogenesis-dependent diseases via endothelial proliferation assay and matrigel tube formation assay; and circulating angiogenesis biomarkers (i.e., free VEGF, soluble FLT-1, and KDR) via ELISA.