HGF and neoplasm: Hypoxic niche induces TAMs to highly express numerous angiogenic and cytokines as well as a large number of angiogenic regulatory enzymes, such as VEGF, PDGF, fibroblast growth factor (FGF1, FGF2), placental growth factor (PIGF), HGF, (bFGF, IL-1, IL-8, MMP-9, MMP-2, TNF-α, urokinase plasminogen activator (uPA), adrenomedullin (ADM) etc., to spur tumor angiogenesis (Peng et al., 2005; Qian and Pollard, 2010; Wang et al., 2011; Zhang et al., 2011; Meng et al., 2012).