Magnetic Paclitaxel Nanoparticles Inhibit Glioma Growth and Improve the Survival of Rats Bearing Glioma Xenografts

Paclitaxel has fared poorly in clinical trials against brain glioma. We hypothesized that superparamagnetic nanocarriers may enhance its bioactivities by delivering it into the brain. The magnetic paclitaxel nanoparticles (MPNPs) were fabricated and their cytotoxicity against glioma was tested both in vitro and in glioma-bearing rats. MPNPs exhibited superparamagnetism and produced an extended release of paclitaxel over 15 days in vitro. They were easily internalized into glioma cells and exerted remarkable toxicity, as free paclitaxel did. Furthermore, after intravenous injection of MPNPs to glioma-bearing rats and magnetic targeting with a 0.5 T magnet, drug content increased for 6- to 14-fold in implanted glioma and 4.6- to 12.1-fold in the normal brain compared to free paclitaxel. The survival of glioma-bearing rats was significantly prolonged after magnetic targeting therapy with MPNPs. MPNPs efficiently delivered paclitaxel into brain glioma by magnetic targeting and enhance its antitumor activity. They are promising for local chemotherapy for malignant glioma.