MMP2 and neoplasm: Having established the changes in microvessel density, cell proliferation and apoptosis index in response to VEGF-Trap and gemcitabine combination therapy, we next sought to investigate the possible mechanism of the combined effects observed in the tumor model in vivo by assessing the expression of cell proliferation (Cyclin D1), anti-apoptosis (Pro-Caspase-3, Bcl-2), and invasion (MMP2, MMP9) related proteins using western blot.