Effective antitumor activity of paclitaxel-loaded poly (epsilon-caprolactone)/pluronic F68 nanoparticles after intratumoral delivery into the murine breast cancer model.

A paclitaxel-loaded poly (epsilon]-caprolactone)(PCL)/pluronic F68 (F68) nanoparticle formulation was prepared as an intratumoral delivery system to assess its potential for future neoadjuvant chemotherapy application in the treatment of breast cancer. Paclitaxel-loaded nanoparticles were prepared by a solvent evaporation method using the self-synthesized PCL/F68 compound. Prepared nanoparticles were spherical with a rough, porous surface. As described in our earlier study, F68 was incorporated into the PCL matrix as both a pore-forming agent and to enhance drug release from the particles. A murine breast cancer model has shown that when using equivalent paclitaxel doses, paclitaxel-loaded PCL/F68 nanoparticles administered by a single intratumoral injection were more efficient in impeding tumor development than conventional paclitaxel injections administered by multiple intraperitoneal injections. In conclusion, paclitaxel-loaded PCL/F68 nanoparticles can be delivered intratumorally and they effectively prevent tumor cell growth and establishment in a localized area. This treatment shows promise as a future neoadjuvant chemotherapy application in the treatment of breast cancer.