EZH2 因其在包括胶质母细胞瘤 (GBM) 在内的许多癌症的转录抑制中具有典型的甲基转移酶活性而闻名，它具有未经充分研究的非典型功能，该功能对于肿瘤的持续生长至关重要。最近 GBM 联盟的努力揭示了复杂的分子异质性，其中与亚型分层相关的治疗脆弱性仍然相对未被探索。目前针对其经典 SET 结构域的酶 EZH2 抑制剂 (EZH2inh) 显示出有限的功效并且缺乏持久的反应，这表明非经典途径的潜在差异可能会产生新的知识。在这里，我们揭示了 EZH2 CXC 结构域在治疗上不同的活性氧 (ROS) 分层肿瘤中的双重作用。我们通过检查顺式调控元件以及活性和途径的聚类来分析 ROS 类别之间的差异表达基因，以识别EZH2 作为 ROS 分层队列中的关键介质。使用 Pull-down 测定和 CRISPR 敲除 EZH2 结构域来剖析 EZH2 在 ROS 分层 GBM 细胞中的独特功能。使用原位患者来源的 GBM 异种移植物评估 NF-κB 诱导激酶抑制剂 (NIKinh) 和标准护理替莫唑胺的疗效。在 ROS() 肿瘤中，CXC 介导的与 RelB 的共同相互作用驱动非典型的 NF-κB2 信号传导，维持 ROS( ) 化疗耐药表型。相反，在 ROS(-) 亚型中，PRC2 甲基转移酶活性抑制典型的 NF-κB。为了解决 EZH2inh 缺乏针对其非甲基转移酶作用的问题，我们利用了一种脑渗透性 NIKinh 来破坏 EZH2-RelB 结合，从而延长原位 ROS( ) 植入小鼠的生存期。我们的研究结果强调了 EZH2 CXC 结构域在管理 ROS 分层治疗耐药性，从而倡导开发针对其非规范活动的治疗方法，并强调患者分层方法的重要性。© 作者 2024。由牛津大学出版社代表神经学会出版-肿瘤学。版权所有。如需商业重复使用，请联系 reprints@oup.com 获取转载和转载的翻译权。所有其他权限都可以通过我们网站文章页面上的权限链接通过我们的 RightsLink 服务获得 - 如需了解更多信息，请联系journals.permissions@oup.com。

EZH2, well-known for its canonical methyltransferase activity in transcriptional repression in many cancers including glioblastoma (GBM), has an understudied non-canonical function critical for sustained tumor growth. Recent GBM consortial efforts reveal complex molecular heterogeneity for which therapeutic vulnerabilities correlated with subtype stratification remain relatively unexplored. Current enzymatic EZH2 inhibitors (EZH2inh) targeting its canonical SET domain show limited efficacy and lack durable response, suggesting that underlying differences in the non-canonical pathway may yield new knowledge. Here, we unveiled dual roles of the EZH2 CXC domain in therapeutically-distinct, reactive oxygen species (ROS)-stratified tumors.We analyzed differentially expressed genes between ROS classes by examining cis-regulatory elements as well as clustering of activities and pathways to identify EZH2 as the key mediator in ROS-stratified cohorts. Pull-down assays and CRISPR knockout of EZH2 domains were used to dissect the distinct functions of EZH2 in ROS-stratified GBM cells. The efficacy of NF-κB-inducing kinase inhibitor (NIKinh) and standard-of-care temozolomide was evaluated using orthotopic patient-derived GBM xenografts.In ROS(+) tumors, CXC-mediated co-interaction with RelB drives constitutive activation of non-canonical NF-κB2 signaling, sustaining the ROS(+) chemoresistant phenotype. In contrast, in ROS(-) subtypes, PRC2 methyltransferase activity represses canonical NF-κB. Addressing the lack of EZH2inh targeting its non-methyltransferase roles, we utilized a brain-penetrant NIKinh that disrupts EZH2-RelB binding, consequently prolonging survival in orthotopic ROS(+)-implanted mice.Our findings highlight the functional dichotomy of the EZH2 CXC domain in governing ROS-stratified therapeutic resistance, thereby advocating for the development of therapeutic approaches targeting its non-canonical activities and underscoring the significance of patient stratification methodologies.© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.