Vitamin E Succinate-Grafted-Chitosan Oligosaccharide/RGD-Conjugated TPGS Mixed Micelles Loaded with Paclitaxel for U87MG Tumor Therapy

The poor therapeutic efficacy of hydrophobic chemotherapeutic drugs is an intrinsic limitation to successful chemotherapy. In the present study, a multitask delivery system based on arginine-glycine-aspartic acid peptide (RGD) decorated vitamin E succinate (VES)-grafted-chitosan oligosaccharide (CSO)/RGD-conjugated d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS-RGD) mixed micelles (VeC/T-RGD MM) was first prepared for targeted delivery of a hydrophobic anticancer drug, paclitaxel (PTX), to improve the efficacy of U87MG tumor therapy. VES grafted CSO (VES-g-CSO) and TPGS-RGD were synthesized as nanocarriers, and PTX loaded VeC/T-RGD MM (PTX@VeC/T-RGD MM) was prepared via the organic solvent emulsification-evaporation method. The PTX@VeC/T-RGD MM was 150.2 nm in diameter with uniform size distribution, 5.92% drug loading coefficient, and no obvious particle size changes within 7 days. The PTX@VeC/T-RGD MM showed sustained-release properties in vitro and high cytotoxicity, and could be efficiently taken up by human glioma U87MG cells. The tumor inhibitory rate of PTX@VeC/T-RGD MM treatment in U87MG tumor spheroids and U87MG tumor bearing mice was 49.3% and 88.4%, respectively, which indicated a superior therapeutic effect. PTX@VeC/T-RGD MM did not damage normal tissues in safety evaluations. These findings suggested that PTX@VeC/T-RGD MM could be developed for the delivery of hydrophobic drugs to U87MG tumors.