Summary:This study primarily focused on the systematic assessment of both in vitro and in vivo anti-tumor effects of docetaxel-loaded polyethylene glycol(PEG)2000-polycaprolactone(PCL)2600micelles on hormone-refractory prostate cancer(HRPC).By using solvent evaporation method,PEG-PCL was chosen to prepare doxetaxel(DTX)-loaded mPEG-PCL micelles(DTX-PMs),with the purpose of eliminating side effects of the commercial formulation(Tween 80)and prolonging the blood circulation time.The prepared DTX-PMs had an average particle size of 25.19±2.36 nm,a zeta potential of0.64±0.15 mV,a polydispersity index of 0.56±0.03,a drug loading of(8.72±1.05)%,and an encapsulation efficiency of(98.1±8.4)%.In vitro cytotoxicity studies indicated that DTX-PMs could effectively kill LNCap-C4-2B cells and show a dose-and time-dependent efficacy.The hemolysis test showed that DTX-PMs had less hemocytolysis than the commercial product of Duopafei.A sustained in vitro release behavior and prolonged circulation time in blood vessels were observed in the DTX-PMs.Furthermore,when compared with Duopafei,the DTX-PMs dramatically reduced the prostate specific antigen(PSA)level and tumor growth of prostate tumor-bearing nude mice in vivo.In conclusion,the DTX-PMs can lower systemic side effects,improve anti-tumor activity with prolonged blood circulation time,and will bring an alternative to patients with HRPC.
