Inhibition of platelet-derived growth factor-mediated proliferation of osteosarcoma cells by the novel tyrosine kinase inhibitor STI571.

Purpose: Osteosarcoma is an aggressive primary bone cancer characterized by expression of platelet-derived growth factor (PDGF) and its cognate receptor. Coexpression of the growth factor and receptor suggests their role in autocrine or paracrine growth mechanisms. It has been reported previously that STI571 has specific activity in inhibiting select tyrosine kinase receptors, including PDGF and c-Kit.