ESTRO 2024 - Abstract Book

S5414

Radiobiology - Tumour biology

ESTRO 2024

A high peak dose while maintaining a biologically tolerable valley dose can result in similar local control rates whilst reducing normal tissue toxicity. However, poorly reported data and highly heterogeneous microbeam parameters in this body of evidence could slow the transition of this promising radiation therapy technique to human clinical trials. There is ambiguity in the literature surrounding what beam widths qualify as a microbeam, blurring the distinction between microbeam and minibeam radiation therapy. Furthermore, the dosimetric parameters were inconsistent throughout the literature, limiting the ability to compare and evaluate results. The dose rates were insufficiently reported, which leads to ambiguity regarding the FLASH effect, and whether the outcome can be attributed to the FLASH effect or not. These research gaps need to be resolved, and standardised reporting guidelines are required at this preclinical stage to encourage inter-institutional research.

Keywords: microbeam, lung cancer

2517

Digital Poster

Kinomics identifies activated Src kinases as target for radiosensitization of head and neck cancer

Malte Kriegs 1,2 , Konstantin Hoffer 1,2 , Henrike Barbara Zech 3 , Lara Bussmann 3 , Clara Marie von Bargen 4 , Tobias Lange 5 , Sabrina Koecher 1 , Thorsten Rieckmann 1,3 , Christian Betz 3 , Cordula Petersen 1 , Kai Rothkamm 1 1 University Medical Center Hamburg-Eppendorf, Hubertus Wald Tumorzentrum – University Cancer Center Hamburg (UCCH), Department of Radiotherapy & Radiation Oncology, Hamburg, Germany. 2 University Medical Center Hamburg-Eppendorf, Hubertus Wald Tumorzentrum – University Cancer Center Hamburg (UCCH), UCCH Kinomics Core Facility, Hamburg, Germany. 3 University Medical Center Hamburg-Eppendorf, Hubertus Wald Tumorzentrum – University Cancer Center Hamburg (UCCH), Department of Otorhinolaryngology, Hamburg, Germany. 4 University Medical Center Hamburg-Eppendorf, Department of Pathology, Hamburg, Germany. 5 University Medical Center Hamburg-Eppendorf, Hubertus Wald Tumorzentrum – University Cancer Center Hamburg (UCCH), Institute of Anatomy and Experimental Morphology, Hamburg, Germany

Purpose/Objective:

Especially for HPV-negative head and neck squamous cell carcinoma (HNSCC) radiotherapy still has to be improved, for example by increasing the radiosensitivity of the tumor cells. In this context, tumor cell specific changes in proteins such as kinases are promising targets for radiosensitizing approaches; however, systematic analyses of oncogenic changes of the kinome of tumor cells are still rare. The purpose of this project was to identify deregulated kinases in HNSCC and to test them for their suitability as prognostic markers and potential molecular targets.

Material/Methods:

Experiments were performed using primary tumor and normal tissue from HNSCC patients, either snap frozen or as slice cultures, as well as established HNSCC cell lines. Functional kinome profiling was used to explore kinases on an omics level while Western blot and immunohistochemistry were used for specific validation. Radiation response and