Isolated protein complexes are provided comprising growth factors such as IGF-I, IGF-II, VEGF or PDGF, or at least domains thereof that enable binding toand activation of both a growth factor receptor, and an integrin receptor-binding domain of vitronectin or fibronectin. These protein complexes may bein the form of oligo-protein complexes or single, synthetic proteins where thegrowth factor and vitronectin or fibronectin sequences are joined by a linkersequence. In particular forms, vitronectin or fibronectin sequences do notinclude a heparin binding domain and/or polyanionic domain. Also provided areuses of these protein complexes for stimulating or inducing cell migrationand/or proliferation which may have use in wound healing, tissue engineering,cosmetic and therapeutic treatments such as skin replacement and skinreplenishment and treatment of burns where epithelial cell migration isrequired. In other embodiments, the invention provides inhibition of cancercell metastasis, particularly in relation to breast cancer.
