MET and neoplasm: NK4 not only acts like an antagonist, inhibiting HGF/c-Met induced tumor growth, metastasis and invasion, but also inhibits vascular endothelial growth factor (VEGF) - and basic fibroblast growth factor (bFGF)-induced tumor angiogenesis, which is independent of the HGF/c-Met pathway, and ultimately causes the tumor cell apoptosis.