Chemo-photothermal therapy combination elicits anti-tumor immunity against advanced metastatic cancer

TLDR

Photothermal therapy (PTT) shows promise for cancer treatment but its requirement for direct light access limits its use against metastatic tumors. The study aims to show that combining PTT with chemotherapy can provoke strong anti‑tumor immunity against disseminated cancers. Polydopamine‑coated spiky gold nanoparticles were engineered as a new photothermal agent with high stability and efficiency. A single round of PTT plus a sub‑therapeutic dose of doxorubicin induced robust immune responses that eradicated both local and distant tumors in over 85 % of CT26 colon carcinoma mice and proved effective against aggressive TC‑1 lung metastasis, highlighting a novel immunological aspect of chemo‑photothermal therapy that may guide future advanced cancer treatments.

Abstract

Photothermal therapy (PTT) is a promising cancer treatment modality, but PTT generally requires direct access to the source of light irradiation, thus precluding its utility against disseminated, metastatic tumors. Here, we demonstrate that PTT combined with chemotherapy can trigger potent anti-tumor immunity against disseminated tumors. Specifically, we have developed polydopamine-coated spiky gold nanoparticles as a new photothermal agent with extensive photothermal stability and efficiency. Strikingly, a single round of PTT combined with a sub-therapeutic dose of doxorubicin can elicit robust anti-tumor immune responses and eliminate local as well as untreated, distant tumors in >85% of animals bearing CT26 colon carcinoma. We also demonstrate their therapeutic efficacy against TC-1 submucosa-lung metastasis, a highly aggressive model for advanced head and neck squamous cell carcinoma (HNSCC). Our study sheds new light on a previously unrecognized, immunological facet of chemo-photothermal therapy and may lead to new therapeutic strategies against advanced cancer.