Investigating lineage plasticity in castration-resistant prostate cancer

项目摘要 临床上使用阿比特龙和恩杂鲁胺等抗雄激素药物， 癌症治疗，但用这些药物治疗的患者仍然会复发，并伴有更具侵袭性的疾病， 统称为去势抵抗性前列腺癌（CRPC）。这些形式的CRPC的特征在于： 谱系可塑性增加，通常与雄激素受体（AR）表达丧失相关， 神经内分泌分化我们的实验室专注于分析正常和非正常组织中的细胞类型分化， 转化的前列腺上皮细胞，最近使用基因工程小鼠模型显示， CRPC中的神经内分泌细胞通过从腔腺癌细胞转分化而产生。初步 为了这个提议，我们已经从这些小鼠前列腺肿瘤中产生了CRPC的类器官模型， 已经通过单细胞RNA测序证明，这些类器官概括了大部分的 人CRPC，包括由AR途径阳性前列腺癌组成的不同异质群体， 神经内分泌前列腺癌和双阴性前列腺癌。进一步分析这些类器官线 揭示了染色质可及性的复杂基因组景观，并确定了活性组蛋白标记 与神经内分泌分化相关的基因。这些发现表明，表观遗传重编程 可能在去势抵抗性前列腺癌的谱系可塑性中起关键作用。 基于这些初步数据，我们假设表观遗传重编程的分子分析 在去势抵抗性前列腺癌中，将确定候选驱动因素和谱系可塑性机制。到 为了研究这一假说，我们将追求三个创新目标，即整合体内、体外、分子和 计算系统方法来分析基因工程小鼠模型，类器官，移植物， 人前列腺肿瘤样品。本研究的具体目的如下：（1）CRPC的谱系可塑性分析 类器官和小鼠模型，以检查不同形式的CRPC之间相互转化的潜在途径; (2)通过检查染色质可及性、组蛋白 标记和DNA甲基化模式，以识别驱动谱系可塑性的表观遗传标记和调节因子; 以及（3）使用计算系统对CRPC中谱系可塑性的候选调节因子进行功能分析 方法，以确定候选调节可塑性其次是实验验证使用类器官和 移植物测定以及人肿瘤样品的分析。总的来说，这些研究将提供必要的 深入了解前列腺癌谱系可塑性和治疗抗性的分子基础，并将有 这对新疗法的发展具有重要意义。

Project Summary The clinical use of anti-androgens such as abiraterone and enzalutamide has greatly improved prostate cancer treatment, but patients treated with these drugs still relapse with more aggressive forms of the disease, collectively termed as castration-resistant prostate cancer (CRPC). These forms of CRPC are characterized by increased lineage plasticity, often associated with loss of androgen receptor (AR) expression and neuroendocrine differentiation. Our laboratory focuses on analyses of cell type differentiation in the normal and transformed prostate epithelium, and has recently used genetically-engineered mouse models to show that neuroendocrine cells in CRPC arise by transdifferentiation from luminal adenocarcinoma cells. In preliminary studies for this proposal, we have generated organoid models of CRPC from these mouse prostate tumors, and have demonstrated by single-cell RNA sequencing that these organoids recapitulate much of the spectrum of human CRPC, including distinct heterogeneous populations composed of AR-pathway positive prostate cancer, neuroendocrine prostate cancer, and double-negative prostate cancer. Further analysis of these organoid lines has revealed a complex genomic landscape of chromatin accessibility, and has identified active histone marks that are associated with neuroendocrine differentiation. These findings indicate that epigenetic reprogramming may play a key role in the lineage plasticity of castration-resistant prostate cancer. Based on these preliminary data, we hypothesize that molecular analysis of epigenetic reprogramming in castration-resistant prostate cancer will identify candidate drivers and mechanisms of lineage plasticity. To investigate this hypothesis, we will pursue three innovative aims that integrate in vivo, ex vivo, molecular, and computational systems approaches to analyze genetically-engineered mouse models, organoids, grafts, and human prostate tumor samples. Our specific aims are as follows: (1) Analysis of lineage plasticity in CRPC organoid and mouse models to examine potential pathways of interconversion between distinct forms of CRPC; (2) Investigation of epigenetic pathways in CRPC organoid models by examining chromatin accessibility, histone marks, and DNA methylation patterns to identify epigenetic marks and regulators that drive lineage plasticity; and (3) Functional analysis of candidate regulators of lineage plasticity in CRPC using computational systems approaches to identify candidate regulators of plasticity followed by experimental validation using organoid and graft assays together with analyses of human tumor samples. Overall, these studies will provide essential insights into the molecular basis of lineage plasticity and treatment resistance in prostate cancer, and will have significant implications for the development of novel therapies.