Clinically approved carbon nanoparticles for enhanced photothermal-immunotherapy toward cancer metastasis

Abstract

The development of new biomedical applications of approved drugs has several advantages in drug translation. In this study, carbon nanoparticle suspension injection (CNSI), clinically approved for lymph node tracer in China, is explored as a photothermal conversion agents for the treatment of metastatic cancer. Metastasis commonly through lymphatic circulation accounts for the principal cause of death in cancer patients. Up to now, immunotherapy has been already used clinically for metastatic cancer. However, the suppressive tumor immune microenvironment limits the effectiveness of immunotherapy. Herein, we use the photothermal effect of CNSI under near-infrared (NIR) irradiation to eliminate primary tumor and induce the immunogenic cell death (ICD). Further, CNSI under irradiation combined with aPD-1 spur immune response and inhibit the growth of distal tumors. Except for the primary tumor, phototherapy was used to treat metastatic lymph nodes synchronously, which can not only eradicate cancer cells, but also directly activate the immune response inside the lymph nodes. Combining with aPD-1 further enhance the anti-tumor effect to block lymphatic metastases and inhibit lung metastases. This study shows that the carbon nanoparticles have potential clinical application prospects for the treatment of tumor metastasis.