ABSTRACT
For advanced pulmonary metastases or melanoma, radiotherapy combined with immune checkpoint inhibitor can block the immunosuppression pathway, enhance the antitumor immune response, and significantly improve survival. Stereotactic body radiation therapy ( SBRT ) delivers a large dose of radiation to the tumor target with high precision while sparing irradiation of the surrounding normal tissues. It is suggested that SBRT could be the most appropriate radiotherapy modality to be combined with immunotherapy since it induces the expression of a series of cytokines and immune molecules and is more likely to cause intense immune response and exert an abscopal effect than conventional radiotherapy. Previous studies have explored that total dose and fractionation seem to be important parameters for determining the immune response;the timing of radiation with immunotherapy significantly influences the outcome, and tumor infiltrating lymphocytes, the expression level of programmed death-ligand 1, and mismatch repair defect may be important predicators of the outcome. With appropriate radiotherapy dose and fractionation, the optimal timing of radiation with immunotherapy, and effective predictive markers, a combination of SBRT and immunotherapy may eliminate advanced malignancies while activating the systemic immune response to exert an abscopal effect.
ABSTRACT
For advanced pulmonary metastases or melanoma, radiotherapy combined with immune checkpoint inhibitor can block the immunosuppression pathway, enhance the antitumor immune response, and significantly improve survival. Stereotactic body radiation therapy ( SBRT ) delivers a large dose of radiation to the tumor target with high precision while sparing irradiation of the surrounding normal tissues. It is suggested that SBRT could be the most appropriate radiotherapy modality to be combined with immunotherapy since it induces the expression of a series of cytokines and immune molecules and is more likely to cause intense immune response and exert an abscopal effect than conventional radiotherapy. Previous studies have explored that total dose and fractionation seem to be important parameters for determining the immune response;the timing of radiation with immunotherapy significantly influences the outcome, and tumor infiltrating lymphocytes, the expression level of programmed death-ligand 1, and mismatch repair defect may be important predicators of the outcome. With appropriate radiotherapy dose and fractionation, the optimal timing of radiation with immunotherapy, and effective predictive markers, a combination of SBRT and immunotherapy may eliminate advanced malignancies while activating the systemic immune response to exert an abscopal effect.
ABSTRACT
Based on a review of currently published 40 papers ( 20 published in recent 5 years, 20 published in recent 10 years) on gold nanoparticles for cancer radiotherapy, the general characteristics, theoretical studies, in vitro experiment, in vivo experiment,and the clinical prospects of targeted radiotherapy with gold nanoparticles were reviewed. Three key aspects guarantee further investigation for the full understanding of the radiosensitization effect of gold nanoparticles:the cellular localization and tissue distribution of nanoparticles and influential factors;the micro dose enhancement effect of gold nanoparticles, and the molecular biological mechanism. More cross disciplinary collaboration, research, development and translation are needed before gold nanoparticles are put into clinical trials.