Aptamer-mediated delivery of docetaxel to prostate cancer through polymeric nanoparticles for enhancement of antitumor efficacy.

Treatment of aggressive prostate cancer remains a great challenge due to inadequate drug distribution into the cancerous lesions after administration. This study aimed to develop aptamer-anchored nanoparticles (apt-NPs) for systemic delivery of docetaxel (DTX) and to evaluate the tumoricidal activity against the prostate cancer in vitro and in vivo. DTX-loaded apt-NPs (DTX-apt-NPs) were prepared by a solvent diffusion technique using functional PLGA-b-PEG and sodium oleate. DTX-apt-NPs were characterized by in vitro release, antitumor activity, cellular uptake and cytotoxic mechanisms. Pharmacokinetics and tissue distribution studies were performed in rats to investigate the biofate of DTX-apt-NPs. Finally, the in vivo antitumor efficacy was examined on the LNCaP cells xenograft tumor model. The resulting DTX-apt-NPs were 93.6nm in particle size with narrow distribution and possessed a high entrapment efficiency (97.62%) and acceptable drug loading (8.91%). DTX-apt-NPs demonstrated an enhanced in vitro antitumor effect and marked cellular uptake compared with the solution formulation or conventional nanoparticles. The intracellular trafficking of DTX-apt-NPs was shown to be an active transport process involving the clathrin-dependent endocytosis. Anti-PSMA aptamer-mediated delivery was assumed mainly responsible for the enhanced antitumor efficacy. DTX-apt-NPs that can target to PSMA-overexpressed prostate cancer provide a feasible approach for systemic delivery of DTX to the cancerous prostate to achieve a fine prognosis.