Polyphosphoester-Based Nanocarriers for Combined X-Ray-Induced Photodynamic Therapy and Immunotherapy

Area of Science:

• Nanomedicine
• Cancer Therapy
• Immunotherapy

Background:

• Photodynamic therapy (PDT) combined with immunotherapy shows promise for cancer treatment.
• PDT's efficacy is limited by light penetration depth, especially for deep-seated tumors.

Purpose of the Study:

• To develop a nanocarrier for co-delivering a photosensitizer and an immunoadjuvant.
• To investigate the efficacy of X-ray-induced photodynamic therapy (X-PDT) combined with immunotherapy for triple-negative breast cancer (TNBC).

Main Methods:

• A self-assembled nanocarrier (NPVR) was synthesized using an amphiphilic copolymer.
• NPVR co-delivered verteporfin (VP) as a photosensitizer and imiquimod (R837) as an immunoadjuvant.
• X-ray irradiation triggered NPVR to induce X-PDT and release R837.

Main Results:

• X-PDT induced by NPVR generated reactive oxygen species (ROS) to kill cancer cells.
• Released R837 promoted immunogenic cell death and dendritic cell maturation, enhancing anti-tumor immunity.
• NPVR-mediated combination therapy achieved approximately 70% tumor growth inhibition in animal models.

Conclusions:

• This novel nanomedicine strategy effectively combines X-PDT and immunotherapy.
• The approach shows significant potential for treating triple-negative breast cancer (TNBC).
• This opens new avenues for designing next-generation nanomedicines for combination cancer therapies.