Novobiocin-mediated polymerase theta inhibition in homologous recombination repair-deficient cancers

同源重组修复缺陷型癌症中新生霉素介导的聚合酶 theta 抑制

• 批准号: 10503123
• 负责人: GEOFFREY I SHAPIRO
• 金额: $ 41.45万
• 依托单位: DANA-FARBER CANCER INST
• 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 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10503123
• 关键词: Advanced Malignant Neoplasm; Antibiotics; BRCA deficient; Base Excision Repairs; Biological; Biological Markers; Biology; Biopsy; Breast; Breast Cancer Model; Cancer cell line; Cell Line; Cells; Chronic; Clinical; Clinical Research; Clinical Trials; Complex; DNA; DNA Damage; Data; Dependence; Development; Dose; Drug Kinetics; Encapsulated; Excision; Genes; Genetically Engineered Mouse; Goals; Human; Immune; Immunocompetent; In Vitro; Knock-out; Link; Maintenance; Malignant Neoplasms; Malignant neoplasm of ovary; Malignant neoplasm of pancreas; Malignant neoplasm of prostate; Marketing; Mediating; Medical; Mus; Mutation; Natural Immunity; Nature; Novobiocin; Ovarian; PARP inhibition; Pathway interactions; Patient-Focused Outcomes; Patient-derived xenograft models of breast cancer; Patients; Pharmacodynamics; Phase; Phase I Clinical Trials; Poly(ADP-ribose) Polymerases; Polymerase; Pre-Clinical Model; Process; Proteins; Residual state; Resistance; Resources; Secure; Solid Neoplasm; Stimulator of Interferon Genes; Testing; Translating; advanced disease; antitumor effect; base; brca gene; cancer cell; combinatorial; design; early phase clinical trial; homologous recombination; immune checkpoint blockade; improved outcome; in vivo; inhibitor; malignant breast neoplasm; mouse model; mutant; p53-binding protein 1; pancreatic cell line; patient derived xenograft model; preclinical study; prevent; recombinational repair; refractory cancer; response; restoration; small molecule; success; tumor; tumor-immune system interactions; two-dimensional

PROJECT SUMMARY/ABSTRACT Homologous recombination (HR) repair-deficient cancers are dependent on polymerase theta (POLq)-mediated DNA end joining, so that POLq is a candidate target for these cancers. This reliance extends to the PARP inhibitor-resistant state, where POLq limits excessive DNA end resection and RAD51 loading, preventing the accumulation of toxic intermediates. POLq deficiency has also been linked to micronucleation, a process associated with activation of innate immunity. Through high-throughput small molecule screens, we have recently identified the antibiotic novobiocin (NVB) as a specific POLq inhibitor that selectively kills HR-deficient cells in vitro and in vivo, including those with acquired PARP inhibitor resistance, suggesting that NVB may be useful alone or in combination with PARP inhibition in treating cancers with HR alterations. NVB also induces micronucleation and consequent cGAS/STING pathway activation in HR-deficient cells. In the first Specific Aim, multiple cell line and patient-derived xenograft models of BRCA-mutant breast, ovarian and pancreatic cancer, including those that are PARP inhibitor-sensitive and those with acquired PARP inhibitor resistance, will be studied for response and pharmacodynamics of NVB combined with the PARP inhibitor talazoparib to compare combinatorial antitumor and biological efficacy to that achieved by monotherapy. Pharmacodynamic effects will be assessed using g-H2AX, pRPA and RAD51 foci as biomarkers of DNA damage, end resection and RAD51 loading, respectively, to pilot their utility for clinical trial. In the second Specific Aim, we will conduct Phase 1 clinical trials of NVB monotherapy and NVB combined with talazoparib in patients with advanced solid tumors harboring HR alterations. The monotherapy study will utilize a BOIN design to determine the recommended phase 2 dose of chronic monotherapy and the combination trial will utilize a waterfall design to define the MTD contour over a two-dimensional dose matrix. Both studies will evaluate pharmacokinetic parameters and incorporate paired biopsies for pharmacodynamic endpoints to establish proof-of-mechanism. The minimum biological effective dose of NVB will be determined in the monotherapy trial, which will guide dosing in the combination study. In the third Specific Aim, NVB used alone and combined with talazoparib will be studied for induction of cGAS/STING activation in vitro, as well as in an immunocompetent genetically engineered mouse model of BRCA-deficient breast cancer. The effects of NVB and NVB/talazoparib on the immune microenvironment will be comprehensively characterized and antitumor activity will be assessed in the absence and presence of immune checkpoint blockade. Taken together, the preclinical and clinical studies in this project are designed to advance NVB-mediated POLq inhibition in the armamentarium for HR-deficient cancers.

项目概要/摘要 同源重组 (HR) 修复缺陷型癌症依赖于聚合酶 theta (POLq) 介导 DNA 末端连接，因此 POLq 是这些癌症的候选靶点。这种依赖延伸到了 PARP 抑制剂抵抗状态，其中 POLq 限制过度的 DNA 末端切除和 RAD51 加载，防止 有毒中间体的积累。 POLq 缺乏也与微成核过程有关 与先天免疫的激活有关。通过高通量小分子筛选，我们有 最近发现抗生素新生霉素 (NVB) 是一种特异性 POLq 抑制剂，可选择性杀死 HR 缺陷型细菌 体外和体内细胞，包括那些具有获得性 PARP 抑制剂耐药性的细胞，表明 NVB 可能是 单独或与 PARP 抑制联合使用可用于治疗 HR 改变的癌症。 NVB还诱导 HR 缺陷细胞中的微成核和随后的 cGAS/STING 通路激活。在第一个具体目标中， BRCA突变乳腺癌、卵巢癌和胰腺癌的多细胞系和患者来源的异种移植模型， 包括那些对 PARP 抑制剂敏感的患者和那些具有获得性 PARP 抑制剂耐药性的患者，将 研究NVB与PARP抑制剂talazoparib联用的反应和药效学以进行比较 组合抗肿瘤和生物功效优于单一疗法。药效作用将 使用 g-H2AX、pRPA 和 RAD51 病灶作为 DNA 损伤、末端切除和 RAD51 的生物标志物进行评估 分别加载以试验其在临床试验中的效用。在第二个具体目标中，我们将进行第一阶段 NVB单药及NVB联合他拉佐帕尼治疗晚期实体瘤的临床研究 隐藏人力资源变动。单一疗法研究将利用 BOIN 设计来确定推荐的 慢性单一疗法的第 2 期剂量和联合试验将利用瀑布设计来定义 MTD 二维剂量矩阵上的轮廓。这两项研究都将评估药代动力学参数和 结合配对活检来确定药效学终点，以建立机制证明。最低 NVB的生物有效剂量将在单药治疗试验中确定，这将指导后续用药 组合研究。在第三个具体目标中，将研究NVB单独使用以及与talazoparib联合使用的效果。 在体外以及免疫活性基因工程小鼠中诱导 cGAS/STING 激活 BRCA缺陷型乳腺癌模型。 NVB 和 NVB/talazoparib 对免疫的影响 将全面表征微环境，并在缺乏的情况下评估抗肿瘤活性 以及免疫检查点封锁的存在。综上所述，该项目的临床前和临床研究 旨在促进 HR 缺陷癌症的治疗中 NVB 介导的 POLq 抑制。