Ultrasound in tumor immunotherapy: Current status and future developments

Area of Science:

• Oncology
• Immunology
• Medical Physics

Background:

• Immunotherapy leverages the host immune system to eliminate cancer.
• Ultrasound (US) applications in tumor therapy include thermal and mechanical effects.
• Modulating the tumor microenvironment is key to enhancing anti-tumor immunity.

Purpose of the Study:

• To review and compare mechanisms of ultrasound-induced immune modulation for peripheral and brain tumors.
• To explore ultrasound's potential in treating degenerative brain diseases.
• To propose novel immunotherapy strategies using microbubble cavitation.

Main Methods:

• Review of existing literature on ultrasound therapy and immunotherapy.
• Analysis of mechanisms including hyperthermia, ablation, histotripsy, and microbubble cavitation.
• Comparison of ultrasound's effects on peripheral versus brain tumor microenvironments.

Main Results:

• Microbubble cavitation enhances immune cell delivery by increasing vascular permeability.
• Violent cavitation disrupts tumor cells, exposing antigens and promoting antigen-presenting cell maturation.
• Ultrasound can potentially reverse tumors to an immunoactive state.

Conclusions:

• Ultrasound, especially via microbubble cavitation, shows significant promise for cancer immunotherapy.
• This modality may offer new therapeutic strategies for brain tumors and degenerative diseases.
• Further research is needed to address challenges and capitalize on opportunities in ultrasound immunotherapy.