Project 1 - Overcoming Breast Cancer Resistance to CDK4/6 Inhibition

项目 1 - 克服乳腺癌对 CDK4/6 抑制的耐药性

• 批准号: 10215411
• 负责人: Peter Sicinski
• 金额: $ 28.11万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-17 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10215411
• 关键词: Adjuvant; Automobile Driving; Biopsy; Breast Cancer Cell; Breast Cancer Patient; Breast Cancer cell line; Breast Carcinoma; Bypass; CDK2 gene; CDK4 gene; Cancer Center; Cell Culture Techniques; Cell Cycle; Cell Cycle Progression; Cell Proliferation; Chloroquine; Clinic; Clinical; Clinical Trials; Complex; Cyclin D1; Cyclin-Dependent Kinase Inhibitor; Cyclin-Dependent Kinase Inhibitor 2A; Cyclin-Dependent Kinases; Data; Development; Disease Progression; Disease Resistance; Engineering; Enzymes; Estrogen receptor positive; Genetic; Goals; Growth; Human; Hydroxychloroquine; Investigation; Laboratories; Lysosomes; Malignant Neoplasms; Metastatic breast cancer; Molecular; Neoadjuvant Therapy; Patients; Phase; Phosphotransferases; Play; Proteins; Resistance; Resistance development; Role; Side; Specimen; Structure; System; Testing; Therapeutic; Therapeutic Effect; Xenograft procedure; analog; cancer cell; efficacy evaluation; human tissue; in vivo; inhibitor/antagonist; malignant breast neoplasm; neoplastic cell; novel; novel strategies; novel therapeutic intervention; overexpression; patient derived xenograft model; phase II trial; prevent; refractory cancer; resistance mechanism; side effect; therapeutically effective; therapy resistant; triple-negative invasive breast carcinoma; tumor

Project Summary Inhibitors of cyclin-dependent kinases CDK4 and CDK6 have been approved for treatment of luminal-type estrogen receptor (ER)-positive breast cancers. Unfortunately, a large proportion of patients with breast cancer develops resistance to CDK4/6 inhibition. In Aim 1, we will test our hypothesis that CDK4/6 resistant breast cancer cells become dependent on hyperactivation of the cyclin-dependent kinase CDK2 for proliferation. Consequently, we hypothesize that inhibition of CDK2 in CDK4/6 inhibitor-resistant cancer cells would block their proliferation. We further hypothesize that combined inhibition of CDK4/6 and CDK2 would have a synergistic effect, and might prevent the development of resistant disease. Currently, a major limitation in studying the role of CDK2 is the absence of CDK2-specific inhibitors. To overcome this limitation, our laboratory has applied the ‘analog-sensitive’ kinase approach, which allows us to specifically, potently and reversibly inhibit CDK2 using a compound that does not inhibit any other kinases. In Aim 1, we will use the analog-sensitive approach to test the impact of CDK2 inhibition on proliferation of CDK4/6-inhibitor resistant tumors in vivo. We will also compare side-by-side the effects of potent CDK2 inhibition using our system, versus CDK2 inhibitors that are currently in clinical trials. In an effort to assess the role of CDK2 in the development of CDK4/6 resistance in the clinic, we will obtain 120 baseline biopsies from patients starting CDK4/6 inhibitor treatment to obtain 60 paired biopsies at baseline and when resistance develops. These biopsies will be interrogated for CDK2 activation status, and we will develop new approaches to gauge CDK2 activity in the clinical setting. In Aim 2, we will extend our investigations to triple negative breast cancer (TNBC). In contrast to luminal-type breast cancers, TNBC is intrinsically resistant to CDK4/6 inhibition. Nonetheless, we have observed that a significant fraction of human TNBC cell lines critically requires CDK4/6 for proliferation. Our preliminary data indicate that CDK4/6 inhibitors become sequestered into TNBC cell lysosomes, thereby blocking the inhibitors’ therapeutic effect. Importantly, we found that treatment of TNBC cells with compounds that inhibit lysosomal acidification, such as chloroquine, reverses the sequestration and renders TNBC cells sensitive to CDK4/6 inhibitor treatment. We also identified a new CDK4/6 inhibitor compound that on its own inhibits proliferation of TNBC cells. We will test the utility of combining CDK4/6 inhibitors with chloroquine for treatment of TNBC, using patient-derived xenografts, as well as short-term cultures of cells isolated directly from human tumors. We will also use these systems to evaluate the efficacy of the novel CDK4/6 inhibitor described above. We will conduct a phase I/II study of palbociclib and chloroquine to test the hypothesis that the addition of chloroquine can circumvent lysosomal sequestration, and patients in this trial will undergo paired biopsies to assess CDK4/6 inhibitor sequestration. The expected overall impact of this proposal is that it may provide a highly effective therapeutic strategy for overcoming acquired resistance to CDK4/6 inhibitors, and may extend the benefits of anti-CDK4/6 therapy to patients with TNBC.

项目摘要 细胞周期蛋白依赖性激酶CDK4和CDK6的抑制剂已批准用于治疗腔型 雌激素受体（ER） - 阳性乳腺癌。不幸的是，很大一部分乳腺癌患者 开发对CDK4/6抑制的抵抗力。在AIM 1中，我们将测试CDK4/6耐药性乳房的假设 癌细胞依赖于细胞周期蛋白依赖性激酶CDK2的过度激活进行增殖。 因此，我们假设CDK2在CDK4/6抑制剂抗癌细胞中的抑制作用会阻止其 增殖。我们进一步假设CDK4/6和CDK2的联合抑制作用将具有协同作用 影响，并可能阻止抗性疾病的发展。目前，研究角色的主要局限性 CDK2的缺乏CDK2特异性抑制剂。为了克服这一限制，我们的实验室应用了 “模拟敏感”激酶方法，这使我们能够使用A特定，潜在和可逆地抑制CDK2 不抑制任何其他激酶的化合物。在AIM 1中，我们将使用模拟敏感方法进行测试 CDK2抑制对体内CDK4/6抑制剂耐药性肿瘤增殖的影响。我们还将比较 并排使用我们系统的潜在CDK2抑制作用，而当前正在的CDK2抑制剂 临床试验。为了评估CDK2在诊所中CDK4/6阻力发展中的作用，我们 将从开始CDK4/6抑制剂治疗的患者中获得120个基线活检，以获得60个配对活检 在基线和阻力发展时。这些活检将被审问有关CDK2激活状态，并将 我们将开发新的方法来评估临床环境中的CDK2活性。在AIM 2中，我们将扩展我们的 研究三重阴性乳腺癌（TNBC）。与腔型乳腺癌相反，TNBC为 对CDK4/6抑制的本质抗性。尽管如此，我们已经观察到大量人类 TNBC细胞系批判性需要CDK4/6进行增殖。我们的初步数据表明CDK4/6抑制剂 隔离到TNBC细胞溶酶体中，从而阻断抑制剂的热作用。重要的是， 我们发现用抑制溶酶体酸化的化合物（例如氯喹）治疗TNBC细胞 逆转隔离并使TNBC细胞对CDK4/6抑制剂治疗敏感。我们也确定了 一种新的CDK4/6抑制剂化合物自身抑制TNBC细胞的增殖。我们将测试 使用患者衍生的异种移植物将CDK4/6抑制剂与氯喹一起治疗TNBC 作为直接从人类肿瘤分离的细胞的短期培养物。我们还将使用这些系统评估 上述新型CDK4/6抑制剂的效率。我们将对palbociclib进行I/II期研究 氯喹检验以下假设：添加氯喹可以绕过溶酶体隔离，并且 该试验中的患者将进行配对的活检以评估CDK4/6抑制剂隔离。总体预期 该提案的影响是，它可以为克服被收购提供高效的治疗策略 对CDK4/6抑制剂的耐药性，并可能扩大抗CDK4/6治疗的益处对TNBC患者。