Regulation of the PCa Metastatic Phenotype by the HSC Niche

HSC 生态位对 PCa 转移表型的调节

基本信息

批准号：
9163106
负责人：
RUSSELL S TAICHMAN
金额：
$ 31.31万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-06-05 至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/9163106
关键词：
Address Biology Blood Blood Circulation Bone Marrow CD44 gene Cancer Patient Cell physiology Cells Clinical Data Set Development Disease Epithelial Future Genes Goals Growth Hematopoietic stem cells Hormones Housing Human In Vitro Individual Invaded Label Malignant Neoplasms Malignant neoplasm of prostate Marrow Mesenchymal Metastatic Neoplasm to the Bone Metastatic Prostate Cancer Modeling Molecular Morbidity - disease rate Mus Neoplasm Metastasis Pathway interactions Patients Phenotype Play Population Positioning Attribute Primary Neoplasm Process Production Prostatectomy Receptor Protein-Tyrosine Kinases Recurrence Regulation Resistance Role Sampling Signal Pathway Signal Transduction Source Stem cells Testing Time Tissues Work base cancer stem cell chemotherapy combat design in vivo innovation men neoplastic cell novel therapeutics patient population phenotypic biomarker prostate cancer cell receptor receptor binding small hairpin RNA stem stem cell niche therapy resistant tumor

项目摘要

Project 2 Project Summary Overview: Prostate cancers (PCa) have an astonishing ability to disseminate, invade and survive in the marrow. Once there, disseminated tumor cells (DTCs) may lie dormant for years. Previously we showed that during metastasis circulating PCa cells target the „niche‟ that houses hematopoietic stem cells (HSC). The niche regulates HSC quiescence. Continuing this work, we show that DTCs recovered from the niche are highly enriched in the CD133+/CD44+ population and express genes associated with a “stem-like” phenotype. The shift in phenotype from CD133- /CD44- to CD133+/CD44+ populations is not seen in cells recovered from other tissues. Further studies show that the HSC niche itself is central to the shift in the DTC phenotype towards a less mature, more cancer stem-like cell–a phenotype which is resistant to chemotherapy. The goal is to more fully understand the biology of the CD133+/CD44+ population. Hypothesis: The acquisition of a cancer stem cell-like state by DTCs once they engage the HSC niche represents a molecular pathway which facilitates dormancy and resistance to therapy. Aim 1: Characterize the biology of CD133+/CD44+ DTC cells isolated from the marrow. We will determine if CD133+/CD44+ isolated from marrow generate (i) spheres in vitro and (ii) generate s.c. tumors in limiting dilution in vivo, (iii) express higher levels of stem cell markers compared to non-niche engaged DTCs, and (iv) using double labeling we will identify which population of DTCs (CD133+/CD44+ or CD133-/CD44-) leads to bone metastases. Aim 2: Elucidate the mechanisms regulating the conversion of CD133-/CD44- into CD133+/CD44+ cells. The change in DTC phenotype upon entering the niche is dependent on growth arrest specific-6. To define the receptors involved shRNA will target each of the three receptor tyrosine kinases (Tyro3, Axl, Mer receptors) that bind to GAS6. (ii) The intracellular signaling pathways activated by GAS6 signaling will be defined to identify mechanisms to block the conversion of CD133-/CD44- into CD133+/CD44+ cells. Aim 3: Identify the extent to which DTCs in humans express CD133, CD44 and GAS6 receptors. We know that 0.5-8% of primary tumor cells express a stem-like phenotype, yet in our models in marrow, 20- 30% of the DTCs express CD133+/CD44+. Based on these data sets, we predict that 20% or more of the DTCs recovered from men will express the stem-like phenotype. To test our hypothesis, 20 sets of paired samples in each of the following patient populations, men pre-prostatectomy (primary, CTCs, DTCs), patients with hormone naive PCa after primary therapy with rising PSA values (DTCs & CTCs), and castrate resistant patients with clinically evident metastatic disease (CTC and DTCs) will be evaluated for the expression of CD133, CD44 and GAS6 receptors.

项目2 项目概要概述：前列腺癌 (PCa) 具有惊人的传播、侵袭和存活能力。一旦到达骨髓，播散性肿瘤细胞（DTC）可能会休眠数年。在转移过程中，循环 PCa 细胞以容纳造血干细胞 (HSC) 的“生态位”为目标。生态位调节 HSC 静止。继续这项工作，我们发现从生态位中回收的 DTC 在 CD133+/CD44+ 中高度富集群体和与“茎样”表型相关的表达基因表型从 CD133- 的转变。进一步的研究表明，在从其他组织中回收的细胞中未发现 /CD44- 至 CD133+/CD44+ 群体。 HSC 生态位本身对于 DTC 表型向不太成熟、更多癌症的转变至关重要干细胞样细胞——一种对化疗有抵抗力的表型，目的是更全面地了解这种细胞。 CD133+/CD44+群体的生物学。假设：一旦 DTC 参与 HSC 生态位，它们就会获得癌症干细胞样状态代表促进休眠和治疗抵抗的分子途径。目标 1：表征从骨髓中分离的 CD133+/CD44+ DTC 细胞的生物学特性。我们将确定从骨髓中分离的 CD133+/CD44+ 是否在体外生成 (i) 球体和 (ii) 皮下生成。体内有限稀释的肿瘤，(iii) 与非利基相比表达更高水平的干细胞标记物 (iv) 使用双重标记，我们将确定哪些 DTC 群体（CD133+/CD44+ 或 CD133-/CD44-) 导致骨转移。目标 2：阐明调节 CD133-/CD44- 转化为 CD133+/CD44+ 细胞的机制。进入生态位后 DTC 表型的变化取决于生长停滞特异性 6。 shRNA涉及的受体将分别针对三种受体酪氨酸激酶（Tyro3、Axl、Mer (ii) GAS6信号传导激活的细胞内信号传导途径将是旨在确定阻止 CD133-/CD44- 转化为 CD133+/CD44+ 细胞的机制。目标 3：确定人类 DTC 表达 CD133、CD44 和 GAS6 受体的程度。我们知道 0.5-8% 的原发性肿瘤细胞表达干细胞样表型，但在我们的骨髓模型中，20- 30% 的 DTC 表达 CD133+/CD44+ 根据这些数据集，我们预测 20% 或更多的 DTC 表达 CD133+/CD44+。从男性身上回收的 DTC 将表现出茎样表型为了检验我们的假设，我们使用了 20 组配对的 DTC。以下每个患者群体的样本，前列腺切除术前的男性（原发性、CTC、DTC）、患者初次接受激素治疗后前列腺癌患者 PSA 值（DTC 和 CTC）上升，且具有去势抵抗性患有临床明显转移性疾病（CTC 和 DTC）的患者将接受评估 CD133、CD44 和 GAS6 受体。