Interestingly, we found that the pro-metastatic MMP9 and the integrin α6β4 protein as well as the metastasis-associated Met72 were both down-regulated in melanoma cells under SMG (Fig. 1F,G), indicating that SMG most likely inhibits melanoma cell invasiveness and metastasis by suppressing expression of these metastasis-related molecules. Here, MMP9 is linked to melanoma.