Neutrophils can release a series of proteins or chemokines, such as Neutrophil Elastase (NE), myeloperoxidase (MPO), cytokines, fibroblast growth factor-2 (FGF-2), matrix metalloproteinase-9 and VEGF to promote tumor proliferation, invasion and angiogenesis (28–30). The gene discussed is MMP9; the disease is neoplasm.