ESTRO 2024 - Abstract Book

S5203

Radiobiology - Microenvironment

ESTRO 2024

pathways after iHD-SBRT that could improve the development of better-oriented combination trials involving high-dose SBRT.

Keywords: Pancreatic cancer, SBRT, Tumor Microenvironment

References:

Hwang WL et al. Single-nucleus and spatial transcriptome profiling of pancreatic cancer identifies multicellular dynamics associated with néoadjuvant treatment. Nat Genet 2022; 54(8):1178-1191

Bouchart et al. Isotoxic high-dose stereotactic body radiotherapy integrated in a total multimodal neoadjuvant strategy for the treatment of localized pancreatic ductal adenocarcinoma. Ther Adv Med Oncol 2021; 13:17588359211045860

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Proffered Paper

FGFR2+ fibroblast-derived BMP5 promoted radioresistance in esophageal carcinoma

Ying WANG 1,2 , Ping FENG 1 , Tong chao JIANG 1 , Yu jia ZHU 1 , Xin yuan GUAN 1,3,4 , Yun fei XIA 1

1 Sun Yat-sen University Cancer Center, Department of Radiation Oncology, Guangzhou, China. 2 Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, China. 3 The University of Hong Kong-Shenzhen Hospital, Shenzhen Key Laboratory for cancer metastasis and personalized therapy, Shenzhen, China. 4 The University of Hong Kong, Department of Clinical Oncology, Hong Kong, Hong Kong

Purpose/Objective:

Radiotherapy is a vital therapeutic strategy for the treatment of esophageal squamous cell carcinoma (ESCC). However, radioresistance impairs patient survival. Our previous studies reported a specific fibroblast growth factor receptor 2-positive (FRFR2+) fibroblast subtype associated with tumor progression; nonetheless, its function remains largely unknown. Our preliminary analysis suggested that high FGFR2+ fibroblast infiltration was closely related to radioresistance.

Material/Methods:

Multiplex immunohistochemistry (mIHC) displayed the distributions of FGFR2+ fibroblasts and cancer stem cells (CSCs). After FGFR2+ fibroblast isolation, tumor cells were stimulated with fibroblasts supernatant to assess radioresistance and CSC properties. RNA-seq analysis identified the downstream BMP5 expression.

Results:

1. High infiltration of FGFR2+ fibroblasts was associated with recurrence after radiotherapy