Mechanisms and small-molecule targeting of SWI/SNF activity in neuroblastoma

神经母细胞瘤中 SWI/SNF 活性的机制和小分子靶向

• 批准号: 10667623
• 负责人: Hamilton Courtney Hodges
• 金额: $ 46.22万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-18 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10667623
• 关键词: 3-Dimensional; ATP phosphohydrolase; Affect; Animal Model; Apoptosis; Biological Assay; Body Weight; Cell Culture Techniques; Cell Cycle; Cell Cycle Deregulation; Cell Cycle Progression; Cell Death; Cell Death Induction; Cell Proliferation; Cells; Cessation of life; Child; Childhood Solid Neoplasm; Clinical; Clinical Trials; Combined Modality Therapy; Complex; Conflict (Psychology); Cytogenetics; DNA; DNA Damage; DNA replication fork; Data; Dependence; Development; Diagnosis; Disease; Drug Combinations; Excision; Fiber; Gamma-H2AX; Gene Amplification; Genetic Transcription; Human; Immunocompetent; Impairment; In Vitro; Infant; Kinetics; MYCN gene; Malignant Childhood Neoplasm; Malignant Neoplasms; Maps; Measures; Modeling; Mus; Neural Crest; Neural Crest Cell; Neuroblastoma; Neurons; Oncogenic; Outcome; Output; Pathway interactions; Patients; Peripheral; Pharmaceutical Preparations; Play; Progression-Free Survivals; Proliferating; Research; Role; S phase; SMARCA4 gene; SWI/SNF Family Complex; Stains; Survival Rate; Therapeutic; Toxic effect; Treatment Efficacy; Tumor Suppressor Proteins; Validation; Work; addiction; advanced disease; chemotherapy; counterscreen; design; effective therapy; hearing impairment; high risk; improved; in vivo; inhibitor; mouse model; nerve damage; neuroblastoma cell; novel strategies; novel therapeutic intervention; pediatric patients; pre-clinical; programs; replication stress; response; small molecule; synergism; temporal measurement; tool; translational study; treatment duration; tumor

Abstract Neuroblastoma (NB) is an aggressive pediatric malignancy originating from cells of neural crest origin. NB is among the most frequent pediatric solid tumors, with 37% of patients diagnosed as infants. Patients with high- risk NB have a five-year survival rate of ~50% despite intensive therapy that can cause several negative outcomes, including low body weight, hearing loss and nerve damage, death, or other sequelae. To improve treatment for these pediatric patients, new approaches are needed. SMARCA4 (BRG1), the primary ATPase of SWI/SNF complexes, has been identified as an oncogenic dependency for NB, with frequent gene amplifications in advanced disease. Unfortunately, the suitability of targeting SWI/SNF ATPase activity and the mechanisms of its inhibition in NB have remained poorly understood. We have employed new fast-acting tools to target SMARCA4 in our preliminary data, which revealed that its inactivation induces profound loss of viability of NB cells independently of MYCN or other cytogenetic features. We have found that inactivation of SMARCA4 induces cell death near the G1-S boundary, consistent with replication stress or cell-cycle dysregulation. In this proposal, we seek to: (1) Map the direct cell cycle-specific effects of SWI/SNF complexes towards DNA accessibility, transcription, and cell death; (2) Identify the mechanisms of cell cycle deregulation and replication stress induced by SWI/SNF inhibition; and (3) Identify tumor-specific synergistic drug combinations in vitro and validate their efficacy in vivo. We will employ a panel of drugs currently used clinically to treat high-risk NB, to examine therapeutic synergy with SWI/SNF inhibition in 2D cells, 3D spheroids, and examine their combination in a rigorous immune-competent mouse model of neuroblastoma. Our strategy to identify combination therapies will be informed by a counter-screen with human neural crest and peripheral neurons, to identify drug combinations that show minimal toxicity to non-tumor cells. Our studies will identify the principal pathways influenced by SWI/SNF inhibition in NB related to replication stress and cell cycle dysregulation. Our findings will furthermore enable identification and validation of therapies that potentiate SWI/SNF blockade in vivo. Because small-molecule SWI/SNF inhibitors are well tolerated by mice, our translational studies represent an important preclinical step that may lead to clinical trials for the 50% of unresponsive high-risk NB patients.

摘要 神经母细胞瘤（NB）是一种起源于神经嵴细胞的侵袭性小儿恶性肿瘤。NB是 在最常见的儿科实体瘤中，有37%的患者在婴儿时被诊断出来。高血压患者- 风险NB的5年生存率约为50%，尽管强化治疗可导致几个阴性结果， 结果，包括低体重、听力损失和神经损伤、死亡或其他后遗症。提高 对于这些儿童患者的治疗，需要新的方法。SMARCA 4（BRG 1），主要的ATP酶， SWI/SNF复合物已被确定为NB的致癌依赖性，具有频繁的基因扩增 在晚期疾病中。不幸的是，靶向SWI/SNF ATP酶活性的适用性和 其在NB中抑制作用仍然知之甚少。我们采用了新的快速反应工具， SMARCA 4在我们的初步数据中，这表明它的失活诱导NB活力的严重丧失， 与MYCN或其他细胞遗传学特征无关。我们发现SMARCA 4的失活 诱导G1-S边界附近的细胞死亡，与复制应激或细胞周期失调一致。在这 我们的目标是：（1）绘制SWI/SNF复合物对DNA的直接细胞周期特异性作用 可及性、转录和细胞死亡;（2）确定细胞周期失调和复制的机制 SWI/SNF抑制诱导的应激;和（3）体外鉴定肿瘤特异性协同药物组合， 验证其在体内的功效。我们将使用一组目前临床上用于治疗高危NB的药物， 在2D细胞、3D球体中检查与SWI/SNF抑制的治疗协同作用，并检查它们的组合 在神经母细胞瘤的严格免疫活性小鼠模型中。我们确定联合治疗的策略 将通过具有人类神经嵴和外周神经元的计数器屏幕来识别药物 这些组合对非肿瘤细胞显示出最小的毒性。我们的研究将确定 在NB中受SWI/SNF抑制的影响与复制应激和细胞周期失调有关。我们的发现将 还能够鉴定和验证体内增强SWI/SNF阻断的疗法。因为 小分子SWI/SNF抑制剂被小鼠良好耐受，我们的翻译研究代表了重要的 临床前步骤，可能导致50%的无反应的高风险NB患者的临床试验。