Regulation of the PCa Metastatic Phenotype by the HSC Niche

HSC 生态位对 PCa 转移表型的调节

• 批准号: 8854468
• 负责人: RUSSELL S TAICHMAN
• 金额: $ 18.1万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-05 至 2020-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8854468
• 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; prostate cancer cell; receptor; receptor binding; small hairpin RNA; stem; stem cell niche; therapy resistant; tumor

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 项目摘要 概述：前列腺癌（PCA）具有惊人的传播，入侵和生存的能力 骨髓。一旦到达那里，散布的肿瘤细胞（DTC）可能会休眠多年。以前我们表明 在转移过程中，循环的PCA细胞靶向容纳造血干细胞（HSC）的“利基市场”。 利基调节HSC静止。 继续这项工作，我们表明从利基市场中回收的DTC在CD133+/CD44+中高度丰富 与“茎状”表型相关的种群和表达基因。 CD133-表型的转移 /CD44-至CD133+/CD44+种群在从其他组织中回收的细胞中看不到。进一步的研究表明 HSC利基本身对于DTC表型转移向不太成熟，更多癌症的核心是核心 茎状细胞 - 一种对化学疗法具有抗性的表型。目标是更充分了解 CD133+/CD44+种群的生物学。 假设：DTC参与HSC生态位，通过DTC的癌症干细胞样态 代表一种分子途径，该途径富含休眠和抗治疗。 目标1：表征从骨髓分离的CD133+/CD44+ DTC细胞的生物学。 我们将确定从骨髓中分离出的CD133+/CD44+是否会在体外产生（i）球，并且（ii）生成s.c. 在体内限制稀释的肿瘤，（iii）与非细胞相比表达更高水平的干细胞标记物 参与DTC，（iv）使用双重标签我们将确定哪些DTC（CD133+/CD44+或 CD133-/CD44-）导致骨转移。 AIM 2：阐明CD133-/CD44-转化为CD133+/CD44+细胞的机制。 进入利基时，DTC表型的变化取决于生长阻滞特异性-6。定义 涉及的shRNA的受体将靶向三个受体酪氨酸激酶（Tyro3，axl，mer 接收器）与gas6结合。 （ii）由GAS6信号激活的细胞内信号通路将是 定义以识别阻断CD133-/CD44-转化为CD133+/CD44+细胞的机制。 目标3：确定人类中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了茎状的表型，但在我们的骨髓模型中，20-- DTC的30％表达CD133+/CD44+。基于这些数据集，我们预测20％或更多 从男性中回收的DTC将表达茎状的表型。为了检验我们的假设，有20组配对 以下每个患者人群中的样本，男性前后切除术（主要，CTC，DTC），患者 初级治疗后，骑马幼稚的PCA具有升高的PSA值（DTC和CTC）和耐castrate的抗性 将评估患有临床证据转移性疾病（CTC和DTC）的患者的表达 CD133，CD44和GAS6受体。