Co-delivery of docetaxel and Poloxamer 235 by PLGA–TPGS nanoparticles for breast cancer treatment

• Cellular uptake of PLGA–TPGS/Poloxamer 235 nanoparticles was increased.
• Significantly higher level of cytotoxicity was found.
• The nanoparticles could overcome multi-drug resistance.

Multidrug resistance (MDR) is a major hurdle to the success of cancer chemotherapy. Poloxamers have been shown to reverse MDR by inhibiting the P-glycoprotein (P-gp) pump. The objective of this research is to test the feasibility of docetaxel-loaded PLGA–TPGS/Poloxamer 235 nanoparticles to overcome MDR in docetaxel-resistant human breast cancer cell line. Docetaxel-loaded nanoparticles were prepared by a modified nanoprecipitation method using PLGA–TPGS and PLGA–TPGS/Poloxamer 235 mixture, respectively. The PLGA–TPGS/Poloxamer 235 nanoparticles were of spherical shape and have a rough and porous surface. The docetaxel-loaded PLGA–TPGS/Poloxamer 235 porous nanoparticles which had an average size of around 180 nm with a narrow size distribution were stable, showing almost no change in particle size and surface charge during the 3-month storage period. The in vitro drug release profile of both nanoparticle formulations showed a biphasic release pattern. There was an increased level of uptake of PLGA–TPGS/Poloxamer 235 porous nanoparticles (PPNPs) in docetaxel-resistant human breast cancer cell line, MCF-7/TXT, in comparison with PLGA–TPGS nanoparticles (PTNPs). The PLGA–TPGS/Poloxamer 235 porous nanoparticles produced significantly higher level of toxicity than both of PLGA–TPGS nanoparticle formulation and Taxotere® both in vitro and in vivo, indicating docetaxel-loaded PLGA–TPGS/Poloxamer 235 porous nanoparticles have significant potential for the treatment of breast cancer.