Harnessing E3 Ligases for Cancer Therapy

利用 E3 连接酶进行癌症治疗

• 批准号: 10204971
• 负责人: Thomas John Maimone
• 金额: $ 47.94万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 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
• 来源: https://reporter.nih.gov/project-details/10204971
• 关键词: Antineoplastic Agents; Azadirachta indica; Binding; Breast Cancer Cell; CDKN1A gene; Cells; Chemicals; Cysteine; Data; Disease; Glues; Human; Impairment; In Situ; In Vitro; Knock-out; Lead; Libraries; Ligands; Link; MDM2 gene; Malignant Neoplasms; Mediating; Modality; Modification; Molecular; Mus; N-terminal; Natural Products; Pathogenicity; Protac; Proteins; Proteome; Role; Technology; Testing; Thalidomide; Therapeutic; Tissues; Tumor Suppressor Proteins; Ubiquitination; activity-based protein profiling; anti-cancer; base; cancer therapy; cell type; chemoproteomics; drug discovery; in vivo; inhibitor/antagonist; innovation; interest; malignant breast neoplasm; multicatalytic endopeptidase complex; novel; prevent; protein degradation; recruit; scaffold; small molecule; targeted cancer therapy; triple-negative invasive breast carcinoma; ubiquitin-protein ligase

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.

靶向蛋白质降解已经成为一种强大的药物发现范式，用于靶向不可药用的药物 用于蛋白酶体降解的蛋白质。该技术利用了称为蛋白水解靶向的双功能降解剂 嵌合体（PROTAC），其由连接至E3连接酶募集物的蛋白质靶向配体组成以泛素化， 蛋白酶体降解感兴趣的蛋白。虽然靶向蛋白质降解可以潜在地用于靶向 任何用于降解的细胞内蛋白，该方法的主要挑战是缺乏E3连接酶 招募人员使用称为基于活性的蛋白质谱（ABPP）的化学蛋白质组学平台， 基于反应性的化学探针来描绘蛋白质组范围内的反应性、功能性和可配体热点，我们 最近发现，抗癌天然产物印楝内酯，一种从印楝中分离出来的三萜类化合物， indica或印楝，与E3泛素连接酶RNF 114的N-末端半胱氨酸（C8）以三重- 阴性乳腺癌细胞。我们的初步数据显示，Nimbolide对RNF 114的共价修饰 导致肿瘤抑制因子p21的泛素化受损， RNF 114-底物结合相互作用，从而为RNF 114的抗癌作用提供了潜在的机制。 这种天然产品。这一认识，即印楝内酯靶向RNF 114内的底物识别结构域 Nimbolide可以潜在地用作用于PROTAC应用的RNF 114的新募集剂。 与这一前提相一致，我们已经证明，将印必利与BRD 4抑制剂JQ 1连接起来的PROTAC XH 2 导致乳腺癌细胞中BRD 4的蛋白酶体依赖性降解。这种降解是RNF 114- 依赖性，如RNF 114野生型细胞中的BRD 4降解所示，但在RNF 114敲除细胞中不存在。在这 建议，我们将结合联合收割机化学蛋白质组学和靶向蛋白质降解平台，研究 RNF 114调节剂在癌症中的治疗潜力以及开发印楝内酯和其它共价键 靶向RNF 114的C8的配体作为PROTAC应用的招募者。