MMP9 and neoplasm: One of them is the adaptive response of the tumor upon prolonged inhibition of VEGF in the presence of persistent hypoxia resulting in the upregulation of other proangiogenic cytokines and angiogenic growth factors (CAF) in the tumor including basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF) and matrix metallopeptidase 9 (MMP-9) [9], a process termed evasive resistance [10].