Disulfiram-loaded copper sulfide nanoparticles for potential anti-glioma therapy

Disulfiram (DSF) is an effective copper (Cu2+)-dependent antitumor agent. In the present study, we explored use of transferrin (Tf)-modified DSF/copper sulfide (CuS) nanocomplex (Tf-DSF/CuS) for glioma therapy. Tf was used as glioma targeting motifs, DSF as an anticancer agent, and CuS as a source of Cu2+ ions and a photothermal agent. DSF was loaded on CuS by metal-chelation, and released from the nanocomplex under acidic condition. The Tf-DSF/CuS complex exhibited high cytotoxic effect in vitro. Notably, cytotoxic activity was correlated with pH triggered release of Cu2+ which initiated non-toxicity to toxicity switch of DSF. Ultrasound-targeted microbubble destruction (UTMD) technique was used for highly selective accumulation of intravenous injected Tf-DSF/CuS in the glioma orthotopic tumor as compared with the free drugs and non-targeted DSF/CuS groups. Magnetic resonance imaging and pathological examinations showed that Tf-DSF/CuS effectively suppressed tumor growth, with an inhibition ratio of ~85%. Additionally, DSF load did not compromise photothermal conversion ability of CuS nanoparticles. Efficacy of the photothermal ablation therapy of Tf-DSF/CuS was evaluated under 808 nm laser irradiation both in vitro and in vivo. These findings show that copper-sulfide based disulfiram nanoparticles are effective agents for anti-glioma therapy.