In-vitro evaluation of paclitaxel-loaded MPEG-PLGA nanoparticles on laryngeal cancer cells

Induction chemotherapy or concurrent chemotherapy with radiotherapy can preserve laryngeal function without a detrimental effect on survival in patients with advanced laryngeal cancer. However, systemic chemotherapy with traditional injection often causes side effects. In this study, methoxy poly(ethylene glycol)-poly(lactide-co-glycolide) (MPEG-PLGA) nanoparticles (NPs) were developed as a carrier for paclitaxel, a potent cytotoxic agent. The NPs were prepared by an emulsification-solvent evaporation method with the particle size and zeta potential around 153.3+/-41.7 nm and -5.36 mV. Transmission electron microscopy showed that the NPs were homogeneous and spherical in shape. Differential scanning calorimetry and X-ray powder diffractometry did not detect any crystalline drug in the NP samples. High-performance liquid chromatography was used to measure the drug loading, encapsulation efficiency, and in-vitro drug release. The drug loading efficiency was (5.35+/-0.75)% and encapsulation efficiency was (75.56+/-2.61)%. In the in-vitro drug release study, paclitaxel was released from the NPs in a slow but time-dependent manner. In-vitro cytotoxicity of the paclitaxel-loaded NPs was investigated by using human laryngeal cancer Hep-2 cells. The anticancer activity of paclitaxel-loaded NPs was comparable with the free paclitaxel. No significant cytotoxicity was observed in blank MPEG-PLGA NPs. Laser scanning confocal microscopy was used to observe the uptake of fluorescent coumarin-6-loaded NPs by Hep-2 cells. We conclude that the formulation of NPs inhibits Hep-2 cell growth to a similar extent as free paclitaxel injection. These results suggest that MPEG-PLGA NPs may have potential as an alternative delivery system for paclitaxel.