Harnessing E3 Ligases for Cancer Therapy

利用 E3 连接酶进行癌症治疗

基本信息

批准号：
10656333
负责人：
Thomas John Maimone
金额：
$ 43.78万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-01 至 2024-06-30
项目状态：
已结题

项目摘要

Targeted protein degradation has arisen as a powerful drug discovery paradigm for targeting undruggable proteins for proteasomal degradation. This technology utilizes bifunctional degraders called proteolysis targeting chimeras (PROTACs) that consist of a protein-targeting ligand linked to an E3 ligase recruiter to ubiquitinate and proteasomally degrade proteins of interest. While targeted protein degradation can potentially be used to target any intracellular protein for degradation, a major challenge of this approach has been the dearth of E3 ligase recruiters. Using a chemoproteomic platform termed activity-based protein profiling (ABPP), which uses reactivity-based chemical probes to profile proteome-wide reactive, functional, and ligandable hotspots, we recently discovered that the anti-cancer natural product nimbolide, a triterpenoid isolated from Azadirachta indica or neem, covalently reacts with an N-terminal cysteine (C8) of the E3 ubiquitin ligase RNF114 in triple- negative breast cancer cells. Our preliminary data revealed that covalent modification of RNF114 by nimbolide leads to impaired ubiquitination of the tumor suppressor p21 through a nimbolide-dependent destabilization of the RNF114-substrate binding interaction, thus providing a potential mechanism for the anti-cancer effects of this natural product. This realization that nimbolide targeted a substrate recognition domain within RNF114 suggested that nimbolide could potentially be used as a novel recruiter for RNF114 for PROTAC applications. Consistent with this premise, we have shown that a PROTAC, XH2, linking nimbolide to a BRD4 inhibitor JQ1 led to proteasome-dependent degradation of BRD4 in breast cancer cells. This degradation was RNF114- dependent, as shown by BRD4 degradation in RNF114 wild-type cells, but not in RNF114 knockout cells. In this proposal, we will combine chemoproteomic and targeted protein degradation platforms to investigate the therapeutic potential of RNF114 modulators in cancer and exploit nimbolide and other covalent ligands targeting C8 of RNF114 as recruiters for PROTAC applications.

靶向蛋白质降解已成为一种强大的药物发现范式，用于靶向不足蛋白质降解的蛋白质。这项技术利用了称为蛋白水解靶向的双功能降解者嵌合体（Protac）由靶向蛋白质的配体组成蛋白酶体降解感兴趣的蛋白质。而靶向蛋白质降解可能可用于靶向任何用于降解的细胞内蛋白质，这种方法的主要挑战是缺乏E3连接酶招聘人员。使用化学蛋白质组学平台称为活性基于活性的蛋白质分析（ABPP）的平台，该平台使用基于反应性的化学探针，以介绍全蛋白质组的反应性反应性，功能和可韧带热点，我们最近发现，抗癌天然产物Nimbolide，一种从Azadirachta分离的三萜 Indica或neEM，共价与E3泛素连接酶RNF114的N末端半胱氨酸（C8）反应负乳腺癌细胞。我们的初步数据表明，Nimbolide对RNF114的共价修改导致通过NIMBOLIDE依赖性不稳定的肿瘤抑制p21的泛素化受损 RNF114-substrate结合相互作用，从而为抗癌作用提供了潜在的机制这种天然产品。这种意识到Nimbolide针对RNF114中的底物识别域建议Nimbolide有可能用作Protac应用的RNF114的新型招聘人员。与此前提一致，我们已经证明了Protac XH2，将Nimbolide与BRD4抑制剂JQ1联系起来导致乳腺癌细胞中BRD4的蛋白酶体依赖性降解。这种降解是RNF114- 依赖性，如RNF114野生型细胞中的BRD4降解所示，但在RNF114基因敲除细胞中不显示。在这个提案，我们将结合化学蛋白质组学和靶向蛋白质降解平台 RNF114调节剂在癌症和利用Nimbolide和其他共价的治疗潜力针对RNF114的C8的配体作为Protac应用的招聘器。

项目成果

期刊论文数量（2）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

A Nimbolide-Based Kinase Degrader Preferentially Degrades Oncogenic BCR-ABL.

DOI：
10.1021/acschembio.0c00348
发表时间：
2020-07-17
期刊：
ACS chemical biology
影响因子：
4
作者：
Tong B;Spradlin JN;Novaes LFT;Zhang E;Hu X;Moeller M;Brittain SM;McGregor LM;McKenna JM;Tallarico JA;Schirle M;Maimone TJ;Nomura DK
通讯作者：
Nomura DK

Ligandability of E3 Ligases for Targeted Protein Degradation Applications.