Enhanced antiproliferative and apoptosis effect of paclitaxel-loaded polymeric micelles against non-small cell lung cancers.

Amphiphilic copolymer monomethoxy poly(ethylene glycol)-poly(caprolactone)-D-α-tocopheryl polyethylene glycol 1000 succinate (MPEG-PCL-TPGS) was prepared. In the present study, MPEG-PCL-TPGS was used as a novel nanovehicle for the delivery of paclitaxel (PTX) in the treatment of resistant lung cancers. The PTX-loaded MPEG-PCL-TPGS (PTX/MPT) micelles exhibited sustained release profile (168 h) with accelerated drug release at acidic pH conditions. The blank polymeric micelles showed excellent biocompatibility with cell viability of >85 %, making it suitable for all in vivo applications. PTX/MPT micelles displayed superior cytotoxicity in A-549 lung cancer cells than that of free PTX. The selective delivery of PTX to cancer cells resulted in enhanced cancer cell death. The PTX/MPT micelles showed higher cellular uptake via endocytosis pathways. The PTX-bound micelles preferentially arrested the cells at G2/M phase and showed a marked increase in sub G1 cell population (∼ 20 %). The pharmacokinetic study revealed a long blood circulation for PTX/MPT micelles. Finally, micellar formulation showed a remarkable tumor suppression effect in resistant A549/Taxol cells bearing xenograft nude mice along with no toxicity profile. The results indicate that the PTX-loaded biocompatible polymeric nanosystem could act as a potential delivery system for the treatment of lung carcinomas.