Development of small molecules to target KDM4B

摘要 组蛋白的表观遗传修饰在调节转录和失调中起关键作用 表观遗传机制的一部分已经成为癌症发生和发展的重要驱动因素。组蛋白 赖氨酸甲基化是组蛋白甲基转移酶动态调控的重要表观遗传标志 “作家”和组蛋白赖氨酸去甲基酶(KDM)。KDM包括两个结构上和 机械上不同类别的酶，有确凿证据表明KDM4B在较大的Jumonji C中 (JmjC)类在乳腺癌、前列腺癌、急性髓系白血病等几种癌症中起着特别关键的作用。 白血病和神经母细胞瘤。我们小组发表的和正在进行的研究支持了 KDM4B在乳腺癌和神经母细胞瘤中的表达。这些结果促使我们开始进行筛查，细胞 生物学和结构生物学努力确定KDM4B的特定抑制剂。我们研究的两个主要发现 提供一个概念证明，靶向KDM4B是癌症的潜在有价值的治疗选择 治疗。首先，N-Myc招募KDM4B以维持Myc结合的低水平抑制H3K9me2/ME3 定位并促进神经母细胞瘤的生长。第二，小分子环吡喃抑制KDM4B活性， 抑制N-Myc途径，减少神经母细胞瘤的生长。 这项提议的直接目标是在这一FOA的范围内开发新的和强大的 KDM4B的抑制剂，在KDM的JmjC类中表现出特异性。这样的抑制剂可以用来 开发有效的体内化学探针来研究KDM4B和KDM家族的其他成员的作用 在相关的临床前癌症模型中。更长期的目标是开发小分子癌症疗法， 目标是KDM4B。此前的生化和结构生物学研究已经彻底表征了该催化剂。 这些酶的机制和底物的特殊性，这些信息将被我们充分利用 继续吧。拥有不同专业知识的四个实验室已经并将继续在这个项目上合作：Jun博士 杨和安德鲁·戴维杜夫(HIT验证)、陈桃生博士(筛查)和斯蒂芬·怀特博士 (生物物理学和结构生物学)。此外，佐兰·兰科维奇博士将提供药物化学 随着我们朝着治疗发展的方向发展，专业知识将变得越来越重要。如定义的 FOA，该项目包括3个阶段：分析开发(阶段1)、初步筛查实施(阶段 2)和命中确认(阶段3)。阶段1和阶段2进展顺利，因此重点将放在阶段 3.

ABSTRACT Epigenetic modifications of histone proteins play key roles in regulating transcription, and dysregulation of the epigenetic machinery has emerged as important driver of cancer initiation and progression. Histone lysine methylation is an important epigenetic mark that is dynamically regulated by histone methyltransferase `writers' and histone lysine demethylase `erasers' (KDMs). The KDMs comprise two structurally and mechanistically distinct classes of enzymes, and there is firm evidence that KDM4B in the larger Jumonji C (JmjC) class has a particularly key role in several cancers including breast and prostate cancer, acute myeloid leukemia and neuroblastoma. Published and ongoing studies from our group support the importance of KDM4B in breast cancer and neuroblastoma. These results have prompted us to initiate screening, cell biology and structural biology efforts to identify specific inhibitors of KDM4B. Two key findings from our studies provide a proof-of-concept that targeting KDM4B is a potentially valuable therapeutic option in cancer treatment. First, N-Myc recruits KDM4B to maintain low levels of repressive H3K9me2/me3 at Myc-binding sites and promotes neuroblastoma growth. Second, the small molecule ciclopirox inhibits KDM4B activity, suppresses the N-Myc pathway and reduces neuroblastoma growth. The immediate goal of this proposal within the scope of this FOA is to develop novel and potent inhibitors of KDM4B that display specificity within the JmjC class of KDMs. Such inhibitors can then be used to develop competent in vivo chemical probes to study the roles of KDM4B and other members of the KDM family in relevant preclinical cancer models. A longer term goal is to develop small molecule cancer therapies that target KDM4B. Previous biochemical and structural biology studies have thoroughly characterized the catalytic mechanism and substrate specificities of these enzymes, and this information will fully exploited as we proceed. Four laboratories with diverse expertise have and will continue to collaborate on this project: Drs. Jun Yang and Andrew Davidoff (hit validation), Dr. Taosheng Chen (screening), and Dr. Stephen White (biophysical studies and structural biology). In addition, Dr. Zoran Rankovic will provide medicinal chemistry expertise that will be increasingly important as we move towards therapeutic development. As defined within the FOA, the project includes 3 stages: assay development (Stage 1), primary screen implementation (Stage 2) and hit validation (Stage 3). Stages 1 and 2 are well advanced and the emphasis will therefore be on Stage 3.