Small Molecule E6 Inhibitors to Treat Oropharyngeal Cancers Caused by HPV Infections

小分子 E6 抑制剂治疗 HPV 感染引起的口咽癌

• 批准号: 10484043
• 负责人: ELLIOT J. ANDROPHY
• 金额: $ 27.58万
• 依托单位: KOVINA THERAPEUTICS INC.
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10484043
• 关键词: Address; Adult; Anatomy; Animals; Antiviral Agents; Apoptosis; Attention; Binding; Biochemical; Biological; Biological Assay; Cancer Etiology; Cell Line; Cells; Clinical; Complex; Coupled; Crystallization; Cysteine; DNA; Data; Docking; Dose; Drug Kinetics; Dysplasia; Etiology; Formulation; Frequencies; Goals; Grant; HIV; HPV oropharyngeal cancer; Human; Human Papilloma Virus Vaccine; Human Papilloma Virus-Related Malignant Neoplasm; Human Papillomavirus; Human papilloma virus infection; Human papillomavirus 16; Immunodeficient Mouse; In Vitro; Incidence; Individual; Infection; Lead; Lesion; Liver Microsomes; Locales; Maintenance; Malignant Neoplasms; Malignant Vaginal Neoplasm; Malignant neoplasm of anus; Malignant neoplasm of cervix uteri; Malignant neoplasm of vulva; Mediating; Medical; Microsomes; Modeling; Morbidity - disease rate; Mus; Neoplastic Cell Transformation; Oncogenic; Oncoproteins; Operative Surgical Procedures; Oral; Oropharyngeal; Papillomavirus Transforming Protein E6; Patients; Pharmaceutical Chemistry; Pharmaceutical Preparations; Pharmacotherapy; Phase; Positioning Attribute; Property; Proteins; Protocols documentation; Radiation therapy; Regimen; Reporting; Safety; Site; Small Business Innovation Research Grant; Solubility; Specificity; Swab; TP53 gene; Technology; Testing; Therapeutic; Toxic effect; Tumor Suppressor Proteins; UBE3A gene; Ubiquitin; Ubiquitination; Validation; Viral Genome; Virus Diseases; Virus Inhibitors; Woman; X-Ray Crystallography; Xenograft Model; adduct; antiviral drug development; aqueous; base; cancer cell; cellular targeting; covalent bond; design; experimental study; high risk; in silico; in vitro activity; in vivo; in vivo Model; in vivo evaluation; inhibitor; malignant mouth neoplasm; malignant oropharynx neoplasm; men; mortality; multicatalytic endopeptidase complex; novel; oral HPV; pharmacokinetic model; population survey; prevent; prophylactic; protein protein interaction; prototype; response; scaffold; screening; small molecule; small molecule libraries; standard of care; tumor; tumor growth; tumor xenograft; ubiquitin ligase

Oncogenic human papillomaviruses (HPV) such as HPV type 16 are the etiologic agent of 50-70% of cancers of the oropharynx. In the USA, the incidence of HPV-associated oropharyngeal cancers is increasing. This is partly because there is no established screening test for oral HPV. HPV-16 DNA is detected by PCR in 1-8% of oral swabs depending on the surveyed populations, with the highest frequencies in HIV+ individuals. Only a small fraction of these infections will progress to frank malignancy. Moreover, early lesions are difficult to locate and patients are largely asymptomatic until they have advanced tumors. Kovina Therapeutics is developing anti-viral therapeutics that selectively bind to the HPV-16 E6 oncoprotein and prevent interactions with its cellular targets. E6 is necessary for viral genome replication and maintenance and is always expressed in HPV-associated dysplasia and malignancies. We performed in silico structural screening of chemical libraries for molecules that fit the E6 docking site for several of its cellular partners. Our assays focused on the E6 protein-protein interaction with E6AP, which transfers ubiquitin onto the tumor suppressor protein p53 and leads to its destruction by the proteasome. We designed and synthesized compounds that 1) bind to HPV-16 E6 and 2) form a covalent bond with a specific cysteine in HPV-16 E6 at its protein-protein interface with E6AP as well as other cellular interacting proteins. The approach to identify molecules equipped with reactive ‘warheads’ that mediate covalent and irreversible binding to cysteine has been successful for several new clinically available drugs, and this field is rapidly progressing to target proteins that were previously considered undruggable. We show that these compounds covalently bind to HPV-16 E6, block E6 interaction with E6AP, restore P53 function, and drive the HPV infected cell to apoptosis. Multiple biochemical analyses including X-ray crystallography prove these inhibitors occupy this E6 pocket and form a single adduct with this cysteine. Iterative optimization guided by the co-crystal data resulted in the design and synthesis of >200 novel chemotypes that resulted in increased activity. This one-year Phase I SBIR proposal will select leads based on for pharmacokinetic characterization. The most promising E6 inhibitors will then be test in vivo proof of concept experiments using human oropharyngeal cancer derived cells in a tumor xenograft model. Successful results in these Phase I experiments will strongly position us for a Phase II SBIR grant to carry out IND-enabling studies.

致癌人乳头瘤病毒 (HPV)，例如 HPV 16 型，是 50-70% 癌症的病原体 口咽部。在美国，HPV 相关口咽癌的发病率正在增加。这是 部分原因是尚无针对口腔 HPV 的既定筛查测试。通过 PCR 检测到 1-8% 的 HPV-16 DNA 口腔拭子的检测取决于调查人群，其中 HIV + 个体的频率最高。只有一个 这些感染中的一小部分将发展为明显的恶性肿瘤。而且早期病变很难定位 患者在肿瘤晚期之前基本上没有症状。 Kovina Therapeutics 正在开发选择性结合 HPV-16 E6 癌蛋白的抗病毒疗法 并阻止与其细胞靶标的相互作用。 E6对于病毒基因组复制和维持是必需的 并且总是在 HPV 相关的发育不良和恶性肿瘤中表达。我们在硅片结构中进行了 筛选化学文库，寻找适合其几种细胞伙伴的 E6 对接位点的分子。我们的 检测重点关注 E6 蛋白-蛋白与 E6AP 的相互作用，E6AP 将泛素转移到肿瘤上 抑制蛋白 p53 并导致其被蛋白酶体破坏。我们设计并合成 这些化合物 1) 与 HPV-16 E6 结合，2) 与 HPV-16 E6 中的特定半胱氨酸在其位点形成共价键。 与 E6AP 以及其他细胞相互作用蛋白的蛋白质-蛋白质界面。识别方法 配备有反应性“弹头”的分子可介导与半胱氨酸的共价和不可逆结合 几种新的临床可用药物取得了成功，并且该领域正在迅速发展到靶向蛋白质 以前被认为是不可成药的。我们证明这些化合物与 HPV-16 E6 共价结合，阻断 E6与E6AP相互作用，恢复P53功能，并驱动HPV感染的细胞凋亡。多重生化 包括 X 射线晶体学在内的分析证明这些抑制剂占据 E6 口袋并形成单一加合物 与这个半胱氨酸。以共晶数据为指导的迭代优化导致了设计和合成 > 200 种新的化学型导致活性增加。这个为期一年的第一阶段 SBIR 提案将选择先导者 基于药代动力学表征。最有前途的 E6 抑制剂随后将进行体内测试 在肿瘤异种移植模型中使用人口咽癌衍生细胞的概念实验。成功的 这些第一阶段实验的结果将使我们能够获得第二阶段 SBIR 拨款来开展 IND 支持 研究。