Rhabdomyosarcoma (RMS) is the main form of pediatric soft-tissue sarcoma. Its cure rate has not notably improved in the last 20 years following relapse, and the lack of reliable preclinical models has hampered the design of new therapies. This is particularly true for highly heterogeneous fusion-negative RMS (FNRMS). Although methods have been proposed to establish FNRMS organoids, their efficiency remains limited to date, both in terms of derivation rate and ability to accurately mimic the original tumor. Here, we present the development of a next-generation 3D organoid model derived from relapsed adult and pediatric FNRMS. This model preserves the molecular features of the patients’ tumors and is expandable for several months in 3D, reinforcing its interest to drug combination screening with longitudinal efficacy monitoring. As a proof-of-concept, we demonstrate its preclinical relevance by reevaluating the therapeutic opportunities of targeting apoptosis in FNRMS from a streamlined approach based on transcriptomic data exploitation.

横纹肌肉瘤（RMS）是小儿软组织肉瘤的主要形式。复发后的过去20年里，其治愈率并没有显着提高，而且缺乏可靠的临床前模型阻碍了新疗法的设计。对于高度异质融合负 RMS (FNRMS) 来说尤其如此。尽管已经提出了建立 FNRMS 类器官的方法，但迄今为止，无论是在衍生率还是准确模拟原始肿瘤的能力方面，其效率仍然有限。在这里，我们展示了源自复发性成人和儿童 FNRMS 的下一代 3D 类器官模型的开发。该模型保留了患者肿瘤的分子特征，并且可以在 3D 中扩展几个月，增强了其对具有纵向疗效监测的药物组合筛选的兴趣。作为概念验证，我们通过基于转录组数据利用的简化方法重新评估 FNRMS 中靶向细胞凋亡的治疗机会，证明了其临床前相关性。