ESTRO 2024 - Abstract Book

S5326

Radiobiology - Tumour biology

ESTRO 2024

caution should be taken before implementing FINs in the clinic, since preliminary results showed that SSZ had a comparable impact on normal tissue as on cancerous tissue. An in-depth exploration of these effects is warranted and will determine whether the translation of FINs as clinical radiosensitizers is feasible.

Keywords: Ferroptosis, Regulated cell death, Toxicity

References:

Kerkhove, L. et al. Cancers 15, 2363 (2023).

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Radiotherapy induces an increase in serum antioxidant capacity reflecting tumor response

Flavia Naumann 1 , Hans J.H.A.M. Kaanders 1 , Wenny W.J.M. Peeters 1 , Gosse J. Adema 1 , Fred C.G.J. Sweep 2 , Jan Bussink 1 , Paul N. Span 1 1 Radboudumc, dept of Radiation Oncology, Nijmegen, Netherlands. 2 Radboudumc, dept of Laboratory Medicine, Nijmegen, Netherlands

Purpose/Objective:

Radiotherapy (RT) is a mainstay component of treatment for patients with head and neck squamous cell carcinoma (HNSCC), but responses vary. As RT relies upon oxidative damage, antioxidant expression in response to RT-induced reactive oxygen species (ROS) could compromise treatment response. We aimed to examine local and systemic antioxidant responses to increased RT-induced ROS in relation to treatment success.

Material/Methods:

Nuclear factor erythroid 2-related factor 2 (NRF2), the main antioxidant transcription factor, was immunofluorescently stained in FaDu cells and in tumor biopsies of patients with oral cavity/oropharynx HNSCC before and after five daily 2Gy fractions of RT. Besides, total antioxidant capacity was analyzed in Fadu, UM-SCC6, UT-SCC24A HNSCC tumor cells in vitro and in serum of HNSCC patients before, during, and after RT.

Results: