Therapeutic Management of Lineage- and Differentiation-state Plasticity

摘要-项目1 肿瘤内异质性是乳腺癌治疗耐药的主要原因。研究 证明了异质性肿瘤中的癌细胞亚群可以逃避治疗诱导的死亡 由于先天性或适应性抗性，导致复发、疾病进展和患者存活率差。 三阴性乳腺癌（TNBC）是一种侵袭性疾病，其特征在于肿瘤内高度异质性 患者预后差。在初步实验中，我们鉴定了原发性肝癌中的肿瘤细胞亚群， 在TNBC以及基底样TNBC细胞系中，所述细胞系的特征在于管腔型，基底型， 和间充质分化状态标志物。我们观察到，不同类别的目标 治疗剂具有消除或富集这些细胞内的特异性分化状态亚群的能力 细胞系，使异质性癌细胞群体朝向增加的同质性。重要的是，我们发现 靶向由主调节因子预测的任一途径依赖性的协同组合治疗 对残留细胞或表观遗传调节因子进行分析，发现这些调节因子有助于细胞向抗性状态的转变。 因此，本项目的总体目标是了解细胞对治疗反应的内在调节， 表型异质性TNBC，以便开发靶向策略来杀死所有共存的TNBC。 亚群我们专注于表型异质性，因为这可以代表遗传和 表观遗传因素，我们将利用临床相关的治疗方法， 人口趋于同质化。我们假设，一种测量和 计算模拟响应中表型状态变化的潜在功能途径 状态聚集疗法将揭示常见的逃逸途径和细胞可塑性的调节剂， 这将使我们能够预测有效的组合治疗策略， 亚群我们将通过（1）检查和计算建模表型来解决这个假设 在多种遗传多样的、异质的TNBC细胞系中响应于靶向的靶向药物的状态变化 使用高内涵成像和单细胞表达分析诱导同质性的治疗剂，（2） 确定是克隆扩增还是分化状态可塑性驱动了动态表型变化 在靶向治疗后，对这些转变背后的分子网络变化进行建模，以及（3） 确定状态转换背后的表观遗传调节，并开发组合策略， 在体外和体内克服异质TNBC细胞中的治疗抗性。总之，这些目标 支持我们测量和模拟细胞对临床相关靶向治疗的内在反应的目标， 以预测更有效地控制异质性TNBC的协同药物组合。整合这 与M2CH-CSBC中的项目2和项目3一起工作将使我们能够将这些内在的外在调节器纳入其中， 机制，并反复完善这种毁灭性疾病的控制策略。 !

ABSTRACT – Project 1 Intratumoral heterogeneity is a major cause of therapeutic resistance in breast cancer. Studies have demonstrated that a subset of cancer cells within a heterogeneous tumor can escape therapy-induced death due to innate or adaptive resistance, resulting in recurrence, disease progression, and poor patient survival. Triple negative breast cancer (TNBC) is an aggressive disease characterized by high intratumor heterogeneity and poor patient outcome. In preliminary experiments, we identified subpopulations of tumor cells in primary TNBC as well as in basal-like TNBC cell lines that are characterized by differential expression of luminal, basal, and mesenchymal differentiation-state markers. We have observed that distinct classes of targeted therapeutics have the capacity to eliminate or enrich specific differentiation-state subpopulations within these lines, steering heterogeneous cancer cell populations toward increased homogeneity. Importantly, we identified synergistic combinatorial treatments that targeted either pathway dependencies predicted by master regulator analysis of residual cells or epigenetic regulators found to contribute to a cell's transition to a resistant state. The overall goal of this project, therefore, is to understand cell intrinsic regulation of therapeutic response in phenotypically heterogeneous TNBC in order to develop targeting strategies to kill all co-existing subpopulations. We focus on phenotypic heterogeneity, as this can represent the combination of genetic and epigenetic factors, and we will take advantage of clinically relevant therapeutics that drive heterogeneous populations toward homogeneity. We hypothesize that a systems biology approach of measuring and computationally modeling the functional pathways underlying phenotypic state changes in response to state-aggregating therapeutics will reveal common escape routes and regulators of cell plasticity, which will allow us to predict effective combinatorial therapeutic strategies that eliminate all cancer subpopulations. We will address this hypothesis by (1) examining and computationally modeling phenotype state changes in multiple genetically diverse, heterogeneous TNBC cell lines in response to targeted therapeutics that induce homogeneity using high-content imaging and single cell expression analysis, (2) determining whether clonal expansion or differentiation state plasticity drives the dynamic phenotype changes following targeted therapy and modeling the molecular network changes that underlie these transitions, and (3) determining epigenetic regulation underlying state transitions and developing combinatorial strategies that overcome therapeutic resistance in heterogeneous TNBC cells in vitro and in vivo. Together, these aims support our goal to measure and model cell intrinsic responses to clinically relevant targeted therapeutics and to predict synergistic drug combinations that more effectively control heterogeneous TNBC. Integration of this work with Projects 2 and 3 in the M2CH-CSBC will allow us to incorporate extrinsic regulators of these intrinsic mechanisms and to iteratively refine control strategies for this devastating disease. !