Ultrasound-Activated Precise Sono-Immunotherapy for Breast Cancer with Reduced Pulmonary Fibrosis

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Immunotherapy

Background:

• Immune checkpoint inhibitors (ICIs) are effective cancer treatments but can cause severe immune-related adverse events (irAEs), including pulmonary fibrosis.
• Programmed death ligand (PD-L1) inhibitor monotherapy has limited efficacy in many cancers.
• Developing safer and more effective immunotherapy strategies is crucial.

Purpose of the Study:

• To design and prepare an intelligent nanodrug for combined sonodynamic therapy (SDT) and immunotherapy.
• To improve cancer treatment response rates and mitigate pulmonary fibrosis associated with immunotherapy.
• To create a novel platform for enhanced breast cancer treatment.

Main Methods:

• Dendritic mesoporous silica nanoparticles (DMSNs) were loaded with protoporphyrin IX (PpIX) and conjugated with a PD-L1 inhibitor (aPD-L1) via a reactive oxygen species (ROS)-sensitive linker.
• Ultrasound (US) was used to activate PpIX, generating ROS that cleaved the linker, releasing aPD-L1 for targeted drug delivery.
• The nanodrug's efficacy was evaluated in terms of tumor inhibition, immune response induction, and reduction of pulmonary fibrosis.

Main Results:

• The nanodrug effectively inhibited tumor growth.
• The sono-immunotherapy approach successfully elicited anti-tumor immune responses.
• Significant reduction in pulmonary fibrosis was observed, indicating improved safety.
• The combination therapy demonstrated superior outcomes compared to monotherapy.

Conclusions:

• The developed nanodrug offers an efficient and safe strategy for breast cancer treatment by combining SDT and immunotherapy.
• This approach effectively enhances immunotherapy response rates and reduces immunotherapy-induced pulmonary fibrosis.
• The study presents a promising new application for nanomedicine in cancer therapy.