Urokinase-like plasminogen activator (uPA) has been implicated in tissue remodeling during such processes as tumor metastasis, wound healing and embryological development. Specific inhibitors of uPA have been developed which will be assayed as inhibitors of experimental metastasis in a mouse melanoma model system. Confirmation of a correlation between the uPA inhibitory and anti-metastatic properties of the compounds will be sought, as will information relating the inhibitors' structural features to their efficacy in vivo. The eventual outcome of confirmation of the efficacy of the drugs tested as anti-metastatic agents is intended to be the identification of a therapeutic agent or agents which will be useful in all cases of diagnosed solid tumors in humans as prophylaxis against metastasis.