Resumo: Osteosarcoma (OS) is a frequent bone cancer, affecting largely children and young adults. Cisplatin (CDDP) has been efficacious in the treatment of different cancer such us OS but the development of chemoresistance and important side effects leading to therapeutic failure. Novel therapies including copper compounds have shown to be potentially effective as anticancer drugs and one alternative to usually employed platinum compounds. The goal of this work is the design, development and evaluation of the in vitro and in vivo antitumoral activity and dilucidate the molecular targets of different Cu(II)-complexes (CuHL1, CuHL2, CuHL3) with tridentate hydrazone derived from tiophen and furan as a ligands against human OS cancer models.