Intravenous delivery of enzalutamide based on high drug loading multifunctional graphene oxide nanoparticles for castration-resistant prostate cancer therapy

Background Enzalutamide (Enz) has shown limited bioavailability via oral administration. Castration-resistant prostate cancer (CRPC) is frequent among patients receiving 18–24 months of androgen deprivation therapy. The nonsteroidal anti-androgen enzalutamide (Enz) used in the treatment of prostate cancer has shown limited bioavailability via oral administration. Therefore, we developed a multifunctional enzalutamide-loaded graphene oxide nanosystem (TP-GQDss/Enz) for CRPC intravenous treatment, with high drug loading efficiency. Methods Aminated graphene quantum dots (GQDs) were first cross-linked via disulfide bonds into a graphene quantum dot derivative of approximately 200 nm (GQDss), which was further functionalized with a tumour-targeting peptide and PEG to form TP-GQDss. Enz was loaded into TP-GQDss for in vitro and in vivo study. Results The results showed that high drug-loading efficiency was achieved by TP-GQDss via π–π electron interaction. TP-GQDss could be rapidly internalized by CRPC cells via endocytosis. Moreover, Enz in TP-GQDss could inhibit the growth of C4-2B and LNCaP prostate cancer cell lines in vitro. Further, TP-GQDss exhibited an enhanced cancer-targeting ability and alleviated the side effects of Enz in vivo. Conclusions The multifunctional nanocarrier constructed here could accomplish controlled Enz release and serve as an intravenous therapy platform for CRPC.