Targeted cancer therapy based on single-wall carbon nanohorns with doxorubicin in vitro and in vivo

Abstract

A new targeted drug delivery system (DDS) based on oxidized single-wall carbon nanohorns (oxSWCNHs) was developed. Sodium alginate (SA) was used to modify oxSWCNHs to improve its dispersibility and biocompatibility, the first time such a modification to oxSWCNHs was reported. The humanized anti-vascular endothelial growth factor (anti-VEGF) monoclonal antibody was bound to the SA as targeting group to selectively kill the tumor cells. Doxorubicin hydrochloride (DOX) was conjugated to oxSWCNHs in basic pH solution by π–π stacking, and its release was triggered by the lower pH as the micro-environment of the tumor. Quantitative analyses showed that the DOX@oxSWCNHs/SA complexes contained 1 g DOX per gram of oxSWCNHs. Cell experiment showed that the DOX@oxSWCNHs/SA-mAb effectively targeted the human breast adenocarcinoma (MCF-7) cells and rarely adhered to the human embryonic kidney 293 (HEK293) cells. And the anticancer effects of the complexes were higher than those of the free DOX. Pharmaceutical efficiency in vivo showed that the relative tumor volumes (RTV) of normal saline (NS) group, oxSWCNH/SA-mAb (2.5 mg/kg) group, DOX (2.5 mg/kg) group, and DOX@oxSWCNHs/SA-mAb (2.5 mg/kg) group were approximately 61, 56, 14, and 7.2, respectively. In addition, higher drug dose (5 mg/kg) of DOX@oxSWCNHs/SA-mAb resulted in a better antitumor activity. Histopathological studies in mice confirmed that the DOX@oxSWCNHs/SA-mAb complexes did not demonstrate any detectable hepatotoxicity, cardiotoxicity, and nephrotoxicity.