Doxorubicin-Conjugated Bisphosphonate Nanoparticles for the Therapy of Osteosarcoma

Osteosarcoma is amongst the most common primary malignant tumors of bone and occurs in adolescents and young adults. Current treatment is a combination of both surgery and chemotherapeutics. However, the use of anticancer drugs is still associated with serious side effects. In this article we describe a doxorubicin drug delivery system based on bisphosphonate nanoparticles with a narrow size distribution. We have shown that the doxorubicin-conjugated bisphosphonate nanoparticles preferentially target the bone tumor, thereby increasing the anti-cancer drug bioavailability to the tumor. Furthermore, we have been able to demonstrate that the doxorubicin-conjugated bisphosphonate nanoparticles have significantly higher activity than the free drug both in vitro and in vivo. Testing the doxorubicin-conjugated bisphosphonate nanoparticles on an osteosarcoma xynograph in a chicken embryo model demonstrated that these nanoparticles specifically targeted the tumor and thus decreased the tumor size.