Photothermal therapeutic effects and biosafety of a carbon nanoparticles–Fe(ii) complex for triple-negative breast cancer

Abstract

Triple-negative breast cancer (TNBC) has become a major challenge in clinical treatment due to its highly aggressive nature and limited therapeutic options. A carbon nanoparticles–Fe(II) complex (CNSI–Fe), as both a ferroptosis inducer and photothermal agent (PTA), could exert anticancer effects through the ferroptosis pathway and photothermal action. Herein, we evaluated the photothermal therapeutic effects of CNSI–Fe in mice bearing the model tumor of TNBC (4T1 tumor). The therapeutic effects of CNSI–Fe were compared without/with near-infrared (NIR) irradiation both in vitro and in vivo. The therapeutic mechanisms and biosafety were also investigated. CNSI–Fe exhibits excellent photothermal conversion efficiency. CNSI–Fe had significant cytotoxicity against TNBC cells, and photothermal therapy (PTT) further enhanced its antitumor effects. The combination of CNSI–Fe and PTT treatments exhibited a more pronounced tumor-suppressive effect and longer survival time comparing to single modality treatment. Mechanistic studies indicated that PTT facilitated the entry of iron ions from CNSI–Fe into cancer cells, generating more hydroxyl radicals and significantly enhancing the ferroptosis. The haematological and serum biological parameters associated with the histopathological observations indicated that the side-effects of CNSI–Fe were low during PTT. Overall, we evidenced the synergistic effect of CNSI–Fe chemotherapy and PTT for TNBC treatment with low toxicity.