Prostate-specific membrane antigen targeted, glutathione-sensitive nanoparticles loaded with docetaxel and enzalutamide for the delivery to prostate cancer

Prostate cancer (PCa) is the most common malignant tumor in men. Chemotherapy with docetaxel (DTX) and novel hormonal agents such as enzalutamide (EZL) and abiraterone are the preferred first-line therapeutic regimens. Prostate-specific membrane antigen (PSMA) is overexpressed on the surface of PCa cells. This study aimed to prepare a PSMA targeted (Glutamate-Urea-Lysine, GUL ligand modified), glutathione (GSH)-sensitive (Cystamine, SS), DTX and EZL co-loaded nanoparticles (GUL-SS DTX/EZL-NPs) to treat PCa. Polyethylene glycol (PEG) was conjugated with oleic acid (OA) using a GSH-sensitive ligand: cystamine (PEG-SS-OA). GUL was covalently coupled to PEG-SS-OA to achieve GUL-PEG-SS-OA. GUL-PEG-SS-OA was used to prepare GUL-SS DTX/EZL-NPs. To evaluate the in vitro and in vivo efficiency of the system, human prostate cancer cell lines and PCa cells bearing mice were applied. Single drug-loaded nanoparticle and free drugs systems were utilized for the comparison of the anticancer ability. GUL-SS DTX/EZL-NPs showed a size of 143.7 +/- 4.1 nm, with a PDI of 0.162 +/- 0.037 and a zeta potential of +29.1 +/- 2.4 mV. GUL-SS DTX/EZL-NPs showed high cancer cell uptake of about 70%, as well as higher cell growth inhibition efficiency (a maximum 79% of cells were inhibited after treatment) than single drug-loaded NPs and free drugs. GUL-SS DTX/EZL-NPs showed the most prominent tumor inhibition ability and less systemic toxicity. The novel GUL-SS DTX/EZL-NPs could be used as a promising system for PCa therapy.