ESTRO 2025 - Abstract Book

S3935

Radiobiology - Normal tissue radiobiology

ESTRO 2025

Figure 1: Kinetics of γH2AX (A) and pATM foci (B) in normal and FA skin fibroblasts. Plotted are the means of three independent experiments ± the standard error of the mean. p-values are represented with * or # when comparing with GM03561 or GM03562, respectively.

Figure 2: Surviving Fraction post IR. Plotted are the means of three independent experiments ± the standard error of the mean. p-values are represented with * or # when comparing with GM03561 or GM03562, respectively. Conclusion: Our findings indicate FA cell lines exhibit an increased radiosensitivity due to deficiencies in their DNA double strand break repair mechanisms. If validated by further research, these results could pave the way for adapting and enhancing treatment strategies for FA by considering their DNA repair deficiency.

Keywords: Friedreich's Ataxia, Radiosensitivity, DNA repair

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Digital Poster Lipoxin A4 Mitigates Radiation-Induced Pulmonary Injury by Modulating Macrophage Polarization Ronglan Cui, Sunjoo Park, Sang Yeon Kim, Haein Jo, Jaeho Cho Radiation Oncology, Yonsei University College of Medicine, Seoul, Korea, Republic of Purpose/Objective: Radiation-induced pneumonia and fibrosis remain critical adverse effects of chest radiotherapy. The complex pathological mechanisms involve interactions between immune cells, resident cells, with macrophages playing an essential role in injury progression and repair. M1 and M2 macrophages has been extensively studied in the context of lung injury, repair and fibrosis. Lipoxin A4 (LXA4), an anti-inflammatory lipid mediator, has shown potential in modulating immune cell activity and promoting tissue repair. Material/Methods: In our study, Raw264.7 cells were stimulated with LPS and IL-4 to induce M1 and M2 macrophages. In vivo, C57BL/6 mouse were chosen to simulate radiation induced lung injury model using X-RAD 320 irradiator. Histopathological