HGF and cancer: However, drug development has been hindered due to poor trial design and therapeutic strategies.600 Encouragingly, potent and specific MMP inhibitors are being developed that may further improve efficacy and attenuate toxicity.1200 In addition, targeted HGF/c-MET inhibitors are bringing light to tumor treatment.677 In conclusion, more than 90% of cancer mortality is now attributed to metastasis, and the prospect of targeted tumor metastasis therapy is unlimited.165