Radiation-induced bystander and abscopal effects: important lessons from preclinical models

Area of Science:

• Oncology
• Immunology
• Radiation Oncology

Background:

• Radiotherapy is a cornerstone in cancer treatment, traditionally understood for its direct cytotoxic effects on tumor cells via DNA damage.
• Emerging evidence reveals a complex interplay between radiotherapy and the host immune system, suggesting non-local effects that influence treatment outcomes.

Purpose of the Study:

• To review the current understanding of radiotherapy's impact on the immune system.
• To explore the preclinical mechanisms underlying the combination of radiotherapy and immunotherapy for synergistic anti-cancer effects.

Main Methods:

• Literature review focusing on preclinical studies and clinical observations.
• Analysis of the dual role of radiation in modulating innate and adaptive immunity.

Main Results:

• Radiotherapy can induce both local tumor cell death and systemic immune responses.
• The combination of radiotherapy and immunotherapy may overcome immune tolerance and exhaustion, promoting tumor regression.

Conclusions:

• Understanding the immunomodulatory effects of radiotherapy is crucial for optimizing combination therapies.
• Further preclinical research is needed to translate these findings into effective clinical strategies for cancer treatment.