Uncovering the Biology of Resistance to Tyrosine Kinase Inhibitors in EGFR Mutant Lung Cancer Patient-Derived Models.

项目摘要 长期的临床观察是转移性癌症对治疗是难治的。即使有 在分子靶向治疗中，耐药性几乎总是出现，患者最终屈服于 癌症的进一步转移扩散。在EGFR突变型肺腺癌（LUAD）的情况下，肿瘤可以 获得对酪氨酸激酶抑制剂（TKI）的抗性，同时扩散到肝脏和大脑。的机制 人们对这些病态结果之间的联系仍知之甚少。在这里，我们建议研究的生物特性， EGFR突变型肿瘤在TKI治疗过程中的演变，确定了允许治疗的肿瘤细胞 持续性以及转移性小生境的特征和对TKI的反应的深度（或持久性）如何联系。我们 假设：1）肿瘤微环境（TME）和肿瘤细胞外在因素是关键决定因素 TKI治疗后播散性肿瘤细胞持续存在，2）对这些因素的依赖性降低 在高耐药转移中的作用。 为了研究这一假设，我们成功地建立了一个重复活检程序， 肺癌标本，包括TKI治疗前后的EGFR突变LUAD。通过这个项目，我们 已经建立了>20个EGFR突变LUAD的患者来源模型，包括类器官培养物， 皮下和原位患者来源的异种移植物（PDX）。在目标1中，我们将产生额外的患者- 作为类器官、皮下或原位PDX的癌症衍生模型（PDMC），收集自10名患者 在TKI治疗前和对TKI获得性耐药时纵向观察EGFR突变LUAD。这些PDMC 将进行基因组学和组织学表征，同时将其TKI敏感性与患者进行比较 标本在目标2中，我们将利用这些模型来确定TKI耐药影响 EGFR突变肿瘤的侵袭性。使用成对的TKI前后PDMC，我们将评估延迟 以及肿瘤复发的部位我们还将确定已知的TKI耐药机制如何影响 EGFR突变型肿瘤的转移特性，并鉴定新的耐药双重分子介质， 转移最后，在目标3中，我们将确定TKI后肿瘤细胞持续存在的组织特异性决定因素 治疗关注我们知道对特定TKI有反应的肿瘤，我们将确定肿瘤是否 植入不同部位的转移瘤对TKI表现出不同的敏感性， 以及这些差异的药理学决定因素。我们将检验基质细胞 细胞外基质调节肿瘤细胞在TKI治疗后持续存在的能力。 胸部恶性肿瘤占大多数癌症相关死亡。通过整合互补的专业知识， 和资源2主要研究者和合作者，我们的目标将提供基本的见解， EGFR突变型LUAD在治疗过程中的纵向演变与药物之间的机制关系 耐药性和肿瘤微环境，这将导致转移性癌症的新治疗策略。

PROJECT SUMMARY A long-standing clinical observation is that metastatic cancers are refractory to treatment. Even with the advent of molecularly targeted therapies, drug resistance almost always emerges and patients ultimately succumb to further metastatic spread of the cancer. In the case of EGFR mutant lung adenocarcinoma (LUAD), tumors can acquire resistance to tyrosine kinase inhibitors (TKI) while spreading to the liver and brain. The mechanisms linking these morbid outcomes remain poorly understood. Here, we propose to study the biological properties of EGFR mutant tumors as they evolve through TKI treatment, identify the factors that allow treated tumor cells to persist and how features of the metastatic niche and depth (or durability) of responses to TKIs are linked. We hypothesize that, 1) the tumor microenvironment (TME) and tumor cell extrinsic factors are critical determinants of disseminated tumor cell persistence following TKI treatment and 2) that the reliance on these factors decreases in highly resistant metastasis through sequential TKI treatment. To study this hypothesis, we have successfully established a repeat biopsy program to collect and analyze lung cancer specimens, including EGFR mutant LUADs before and after TKI treatment. Through this program we have established >20 patient-derived models of EGFR mutant LUAD, including organoid cultures and subcutaneous and orthotopic patient-derived xenografts (PDXs). In Aim 1, we will generate additional patient- derived models of cancer (PDMCs) as organoids, subcutaneous or orthotopic PDXs, collected from 10 patients with EGFR mutant LUAD longitudinally prior to TKI treatment and at acquired resistance to TKIs. These PDMCs will be genomically and histologically characterized, while their TKI sensitivity will be compared to the patient specimens. In Aim 2, we will leverage these models to determine the mechanisms by which TKI resistance affects the aggressiveness of EGFR mutant tumors. Using paired pre- and post-TKI PDMCs, we will evaluate the latency and site of relapse of these tumors. We will also determine how known mechanisms of TKI resistance affect the metastatic properties of EGFR mutant tumors and identify novel dual molecular mediators of resistance and metastasis. Finally, in Aim3, we will Identify tissue-specific determinants of tumor cell persistence following TKI treatment. Focusing on tumors that we know are responsive to specific TKIs, we will establish whether tumors implanted in different sites of metastases exhibit different sensitivity to TKIs and identify the cellular, molecular and pharmacological determinants of these differences. We will test the mechanistic prediction that the stromal extracellular matrix modulates the ability of tumor cells to persist upon TKI treatment. Thoracic malignancies account for most cancer-related deaths. By integrating the complementary expertise and resources of 2 principal investigators and collaborators, our aims will provide fundamental insights into the longitudinal evolution of EGFR mutant LUAD under treatment and the mechanistic relationship between drug resistance and the tumor microenvironment, which will lead to new therapeutic strategies for metastatic cancers.