Xu Ruiling, Zhu Sai, Zhang Wenchao, Xu Haodong, Tu Chao, Wang Honghui, Wang Lu, He Na, Liu Tang, Guo Xiaoning, Ren Xiaolei, Li Zhihong
Department of Orthopedics, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, P. R. China.
Hunan Key Laboratory of Tumor Models and Individualized Medicine, The Second Xiangya Hospital, Changsha, Hunan, 410011, P. R. China.
Adv Sci (Weinh). 2025 Jul;12(28):e2500632. doi: 10.1002/advs.202500632. Epub 2025 Jun 6.
Osteosarcoma (OS), the most prevalent primary bone malignancy in adolescents, is typically treated with cisplatin-based chemotherapy. However, the development of cisplatin resistance often leads to relapse or metastasis, significantly impairing therapeutic efficacy. To tackle this issue, patient-derived osteosarcoma organoids (OSOs) is established that accurately reflect the cellular composition and heterogeneity of the original tumors, as validated by single-cell RNA sequencing, bulk RNA sequencing, and histopathology analysis. Cisplatin resistance is successfully induced in these OSOs, creating a clinically relevant model for investigating chemoresistance. Utilizing RNA sequencing in cisplatin-resistance OSOs and CRISPR screening in OS cell line, ERCC6 is identified as a pivotal regulator of cisplatin resistance. Knockdown of ERCC6 markedly enhanced cisplatin sensitivity in vitro and in vivo. Mechanistically, ERCC6 interacts with HNRNPM, influencing the PI3K/AKT signaling pathway and alternative splicing of pre-mRNA for BAX. Notably, the knockdown of ERCC6 and HNRNPM increased expression of full-length BAX and reduced skipping of exon 2, thus promoting apoptosis. This exon skipping in BAX results in a frameshift and introduces a premature stop codon (TGA) within the BH3 domain. These findings underscore the utility of OSOs in elucidating resistance mechanisms and highlight ERCC6 and HNRNPM as potential therapeutic targets.
骨肉瘤（OS）是青少年中最常见的原发性骨恶性肿瘤，通常采用以顺铂为基础的化疗进行治疗。然而，顺铂耐药性的出现常常导致复发或转移，显著损害治疗效果。为了解决这个问题，建立了患者来源的骨肉瘤类器官（OSO），经单细胞RNA测序、批量RNA测序和组织病理学分析验证，其能准确反映原发肿瘤的细胞组成和异质性。在这些OSO中成功诱导出顺铂耐药性，创建了一个用于研究化疗耐药性的临床相关模型。利用顺铂耐药性OSO中的RNA测序和OS细胞系中的CRISPR筛选，确定ERCC6是顺铂耐药性的关键调节因子。敲低ERCC6显著增强了体外和体内的顺铂敏感性。从机制上讲，ERCC6与HNRNPM相互作用，影响PI3K/AKT信号通路以及BAX前体mRNA的可变剪接。值得注意的是，敲低ERCC6和HNRNPM增加了全长BAX的表达并减少了外显子2的跳跃，从而促进细胞凋亡。BAX中的这种外显子跳跃导致移码，并在BH3结构域内引入一个过早的终止密码子（TGA）。这些发现强调了OSO在阐明耐药机制方面的实用性，并突出了ERCC6和HNRNPM作为潜在治疗靶点的重要性。
