Structure-guided development of chemical inhibitors against Kaposi’s sarcoma-associated herpesvirus (KSHV)

针对卡波西肉瘤相关疱疹病毒 (KSHV) 的化学抑制剂的结构引导开发

• 批准号: 9791594
• 负责人: REN SUN
• 金额: $ 20.36万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9791594
• 关键词: Acquired Immunodeficiency Syndrome; Adverse effects; Affinity; Antiviral Agents; Atmosphere; Binding; Binding Sites; Biological Assay; Capsid; Capsid Proteins; Cell Proliferation; Cells; Chemicals; Complement; Cryoelectron Microscopy; DNA; DNA biosynthesis; Development; Disease; Docking; Dose; Drug Targeting; Drug resistance; Electrons; Epstein-Barr Virus Infections; Etiology; Evaluation; Family; Fluorescence; Future; Genome; Goals; HIV; Hairy Leukoplakia; Herpesviridae; Herpesviridae Infections; Human; Human Herpesvirus 4; Human Herpesvirus 8; Hydrophobicity; In Vitro; Infection; Infectious Mononucleosis; Inflammatory; Interruption; Kaposi Sarcoma; Lead; Life; Life Cycle Stages; Link; Lymphoproliferative Disorders; Lytic Phase; Malignant Neoplasms; Methods; Modification; Molecular; Multicentric Angiofollicular Lymphoid Hyperplasia; Mutagenesis; Nasopharynx Carcinoma; Nucleic Acids; Patients; Peptides; Pharmaceutical Preparations; Phase; Process; Production; Property; Proteins; Public Health; Reproducibility; Research; Resistance; Resolution; Risk; Signal Transduction; Site; Structure; Symptoms; Syndrome; Testing; Toxic effect; Viral Load result; Virion; Virus; Virus Latency; angiogenesis; antiretroviral therapy; base; cytokine; cytotoxicity; druggable target; ds-DNA; fighting; gammaherpesvirus; high throughput screening; improved; in vivo; inhibitor/antagonist; latent infection; lytic replication; member; mortality; mutant; novel; nucleic acid analog; post-transplant; pressure; prevent; primary effusion lymphoma; protein crosslink; side effect; small molecule libraries; tool; tumor; tumorigenesis; viral DNA

PROJECT SUMMARY Kaposi's sarcoma-associated herpesvirus (KSHV), a member of the gamma-herpesvirus subfamily, has been shown to be an etiologic agent of Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman's disease. Kaposi's sarcoma is the most common malignancy associated with infection of human immunodeficiency virus (HIV) and develops in about 20% of acquired immunodeficiency syndrome (AIDS) patients without antiretroviral therapy. Viral latency of KSHV is thought to be directly linked to tumorigenesis, but viral lytic replication also contributes to tumorigenesis, directly and indirectly. Therefore, it is important to develop specific lytic replication inhibitors to control KSHV-associated cancers. Currently, the majority of the available drugs fighting herpesvirus infection are nucleic acid analogues targeting viral DNA synthesis. However, these nucleic acid drugs show extensive adverse effects including the frequent induction of drug resistant mutant viruses and various kinds of toxicity. Moreover, no drugs specifically targeting KSHV infection is available. Therefore, there is a need for the development of anti-KSHV drugs. We believe that aside from viral DNA synthesis, virus capsid assembly, which is a critical step for the production of progeny virions, can serve as a novel and potent drug target. KSHV capsids contain 955 capsid subunits. These subunits form a pressure-resistant network to withhold tens of atmospheres of pressure generated by its condensed ~150-kb dsDNA genome. We hypothesize that if an inhibitor binds to any one of the 955 capsid units, it will either prevent the formation of the capsid or result in an unstable capsid which bursts under the high pressure. The key point is that only one of the 955 units has to be targeted, thereby reducing the drug-to-target ratio by about a thousand-fold. Potentially, this method can reduce a drug's dose by ~ 3-Log, significantly minimizing its possible toxicity and side effects. In other words, the high internal pressure and large number of subunits make herpesvirus capsid assembly prone to interruption and can therefore be targeted for the structure-guided development of antiviral agents. Recently, we resolved the atomic-resolution structure of the KSHV capsid by employing electron-counting cryo- electron microscopy (cryoEM). Guided by the cryoEM structure and functional analysis results, we identified a promising druggable site, which is a hydrophobic groove on the upper-domain of Major Capsid Protein (MCP). The objective of this R21 application is to identify chemical inhibitors targeting this druggable site with the following specific aims: 1) to identify chemical inhibitors by two complementary high-throughput screenings, and 2) to identify lead compounds by functional evaluation. The lead compounds, which interrupt herpesvirus capsid assembly, will not only be a useful tool for scientific research but also have the potential to be the first- in-class drugs against herpesvirus infection.

项目摘要 Kaposi的肉瘤相关疱疹病毒（KSHV）是Gamma-Hepesvirus subfimily的成员 被证明是Kaposi的肉瘤，一级积液淋巴瘤和多中心Castleman的病因学剂 疾病。卡波西的肉瘤是与人类感染相关的最常见恶性肿瘤 免疫缺陷病毒（HIV），大约有20％获得的免疫缺陷综合征（AIDS）发展 没有抗逆转录病毒疗法的患者。 KSHV的病毒潜伏期被认为与肿瘤发生直接相关， 但是病毒裂解复制也直接和间接地导致肿瘤发生。因此，重要的是 开发特定的裂解复制抑制剂，以控制KSHV相关的癌症。目前，大多数 抗疱疹病毒感染的可用药物是针对病毒DNA合成的核酸类似物。 但是，这些核酸药物显示出广泛的不良反应，包括频繁诱导药物 抗性突变病毒和各种毒性。此外，没有专门针对KSHV感染的药物 可用。因此，需要开发抗KSHV药物。我们相信除了 病毒DNA合成，病毒衣壳组件，这是产生后代病毒体的关键步骤，可以 充当一种新颖而有效的药物靶标。 KSHV衣壳包含955个衣壳亚基。这些亚基形成一个 抗压网络，以防止其冷凝约150 kb产生的压力大气 DSDNA基因组。我们假设，如果抑制剂与955个衣壳单元中的任何一个结合，则可以 防止在高压下爆裂的衣壳形成或导致不稳定的衣壳。这 关键点是，只有955个单元中只有一个目标，从而将药物与目标比率降低了大约 一千倍。可能，这种方法可以减少〜3型药物的剂量，从而显着最大程度地减少其剂量 可能的毒性和副作用。换句话说，高内部压力和大量亚基使 疱疹病毒衣夹容易中断，因此可以针对引导的结构 抗病毒剂的发展。 最近，我们通过采用电子计算冷冻 - 电子显微镜（冷冻）。在冷冻结构和功能分析结果的指导下，我们确定了一个 有前途的可药物位点，这是主要衣壳蛋白上域（MCP）的疏水凹槽。 该R21应用的目的是确定针对该可毒位点的化学抑制剂 以下特定目的：1）通过两个互补的高通量筛选鉴定化学抑制剂， 2）通过功能评估识别铅化合物。铅化合物，中断疱疹病毒 衣壳组件，不仅将成为科学研究的有用工具，而且有可能成为首先 针对疱疹病毒感染的课堂药物。