HGF and neoplasm: Chemokines and growth factors, such as HGF, seem to act as mediators between the tumour microenvironment and the neoplastic cells, and are important in tumour progression and metastasis (Matsumoto and Nakamura, 2006; Benvenuti and Comoglio, 2007; Desiderio, 2007; Singh et al, 2007).