PDGF D AND PROSTATE CANCER BONE METASTASIS

PDGF D 与前列腺癌骨转移

• 批准号: 8205007
• 负责人: Hyeong-Reh Choi Kim
• 金额: $ 30.59万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8205007
• 关键词: Affect; Animals; Biological; Biological Assay; Bone Growth; Bone Matrix; Bone Resorption; Bone remodeling; C-terminal; Cancer Patient; Cell Communication; Cell Line; Cell Proliferation; Cell Surface Receptors; Cell surface; Cleaved cell; Clinical; Clinical Trials; Complement Factor D; Data; Deposition; Diagnostic Neoplasm Staging; Event; Excision; Fibrin fragment D; Generations; Gleason Grade for Prostate Cancer; Goals; Growth; Growth Factor; Homeodomain Proteins; Human; In Vitro; Injection of therapeutic agent; LNCaP; Length; Ligands; Lytic; Malignant Epithelial Cell; Malignant neoplasm of prostate; Mediating; Mesenchymal; Metastatic Neoplasm to the Bone; Modeling; Molecular; N-terminal; Neoplasm Metastasis; Organ Culture Techniques; Osteoblasts; Osteoclasts; Osteogenesis; Osteolytic; PDGFRB gene; Phosphorylation; Platelet-Derived Growth Factor; Platelet-Derived Growth Factor Receptor; Platelet-Derived Growth Factor beta Receptor; Principal Investigator; Process; Prostate carcinoma; Prostatic Neoplasms; Proteolytic Processing; Proto-Oncogene Proteins c-sis; Reaction; Reading; Receptor Signaling; Regulation; Reporting; Research; Role; Sampling; Serine Protease; Signal Transduction; Signal Transduction Pathway; Site; Specimen; Stromal Cells; Stromal Neoplasm; Structure; Structure of base of prostate; Subcutaneous Injections; TNFSF11 gene; Tertiary Protein Structure; Testing; Therapeutic; Tumor stage; Tumor-Derived; Vascular Endothelial Growth Factors; bone; cell growth; cytokine; dimer; extracellular; in vitro Model; inhibitor/antagonist; matriptase; monomer; mouse model; neoplastic cell; novel; osteoblast differentiation; osteoclastogenesis; overexpression; paracrine; public health relevance; receptor; response; skeletal; tibia; tumor; tumor growth; tumor progression

DESCRIPTION (provided by applicant): The objective of this research application is to unveil the molecular and cellular mechanisms by which prostate carcinoma-produced platelet-derived growth factor (PDGF) regulates osteoclastic bone resorption and new bone growth, creating a favorable microenvironment for metastatic deposit. Increasing evidence indicate the significance of PDGF receptor signaling, especially 2-PDGFR, in prostate cancer progression and bone metastasis. PDGF B, however, originally thought to be the sole ligand for 2-PDGFR, has rarely been found in prostate cancer clinical samples. Importantly, our recent immunohistochemical analysis of human prostate carcinoma specimens showed that increased expression of PDGF D, a newly discovered ligand for PDGF receptor-beta (2-PDGFR), is associated with increased Gleason scores and tumor stages. Whereas the classic PDGF ligands A and B are secreted as active dimers, PDGF D contains an N-terminal CUB domain and a C terminal PDGF domain which is secreted as a latent dimer. Extracellular proteolytic cleavage of the CUB domain is required for the PDGF domain to stimulate 2-PDGFR. Recently, we made a novel finding that human prostate carcinoma cells auto-activate latent PDGF D into an active growth factor domain of PDGF D utilizing the serine proteases uPA and matriptase. Consistent with previous reports that matriptase is frequently overexpressed in prostate cancer, especially in metastatic samples, our preliminary data showed increased matriptase expression in human prostate cancer. In a tibiae-injection model, PDGF D significantly enhanced tumor take and growth rate of LNCaP tumors with increased osteolytic and osteoblastic responses. Additionally, our in vitro study unveiled exciting new roles of PDGF D in the regulation of osteoclast differentiation independent of the RANKL/RANK signaling axis as well as osteoblast differentiation involving modulation of homeoprotein expression. Taken together, we hypothesize that prostate carcinoma-produced PDGF D, activated by the transmembrane serine protease matriptase, induces paracrine cell signaling in bone stromal cells, mediating tumor-stromal interactions critical for prostate carcinoma growth in the bone microenvironment. To test this hypothesis, we propose (1) To investigate matriptase-mediated proteolytic processing of PDGF D; (2) To investigate the molecular mechanisms by which PDGF D induces osteoclast and osteoblast differentiation using in vitro models of RAW264.7 and MC3T3-E1 cell lines; and (3) To investigate the roles of PDGF D and its functional regulator matriptase in bone stromal responses and prostate tumor growth in animals. Considering that 2-PDGFR as well as matriptase is highly upregulated in both bone metastases and primary prostate cancer specimens, the completion of the proposed study of interplay between PDGF D, a specific activator of 2-PDGFR, and matriptase will help us in understanding the molecular basis for prostate cancer progression. In addition, the proposed study may provide important information with therapeutic value, especially given that VEGF/PDGF inhibitors are currently in clinical trials for cancer patients. PUBLIC HEALTH RELEVANCE: Mesenchymal growth factors, produced by tumor cells, activate their cognate receptors expressed in surrounding stromal cells, mediating tumor-stromal interactions. These interactions are thought to be critical for tumor progression at both the primary and the metastatic sites. A vast majority of prostate cancer (PC) metastases occur at skeletal sites. The mechanisms underlying the marked propensity of PC to metastasize to bone are beginning to be understood. Although still debatable, it is believed that cell surface and secreted factors produced by the tumor cells induce an osteoclastic response, a critical initial step for PC growth in bones. Bone resorption by osteoclasts results in the release of growth factors and cytokines from the bone matrix, providing a favorable microenvironment for tumor cell proliferation and invasion. Bone formation follows or accompanies bone destruction, and these bone reactions eventually become extensive enough to be visible on radiographs as both sclerotic and lytic reactions. Increasing evidence suggests that platelet-derived growth factor (PDGF) mediates tumor-stromal interactions during human prostate cancer bone metastasis. The goal of this project is to investigate the molecular mechanisms by which prostate carcinoma-produced PDGF initiates bone remodeling, a critical event for tumor cell colonization to the bone. In this application, we will test our hypothesis that the tumor-associated serine proteinase, matriptase, regulates the biological activity of the newly discovered PDGF ligand, PDGF D, and that tumor-derived PDGF D regulates osteoclast differentiation as well as osteoblast proliferation/differentiation critical for tumor cell growth.

描述（由申请人提供）：本研究申请的目的是揭示前列腺癌产生的血小板衍生生长因子（PDGF）调节骨细胞骨吸收和新骨生长的分子和细胞机制，为转移性存款创造有利的微环境。越来越多的证据表明PDGF受体信号传导，特别是2-PDGFR，在前列腺癌进展和骨转移中的重要性。然而，PDGF B最初被认为是2-PDGFR的唯一配体，在前列腺癌临床样品中很少发现。重要的是，我们最近对人前列腺癌标本的免疫组织化学分析显示，PDGF D（一种新发现的PDGF受体β（2-PDGFR）配体）表达增加与Gleason评分增加和肿瘤分期相关。传统的PDGF配体A和B作为活性二聚体分泌，而PDGF D含有N-末端CU B结构域和C-末端PDGF结构域，其作为潜伏二聚体分泌。PDGF结构域刺激2-PDGFR需要CUB结构域的细胞外蛋白水解裂解。最近，我们发现了一个新的发现，人前列腺癌细胞利用丝氨酸蛋白酶uPA和基质蛋白酶将潜在的PDGF D自动激活为PDGF D的活性生长因子结构域。与先前的报告一致，即matriptase在前列腺癌中经常过表达，特别是在转移性样品中，我们的初步数据显示，matriptase在人前列腺癌中的表达增加。在胫骨注射模型中，PDGF D显著增强了LNCaP肿瘤的肿瘤摄取和生长速率，增加了溶骨和成骨细胞反应。此外，我们的体外研究揭示了PDGF D在调节破骨细胞分化（不依赖于RANKL/RANK信号传导轴）以及成骨细胞分化（涉及同源异型蛋白表达的调节）中令人兴奋的新作用。综上所述，我们假设前列腺癌产生的PDGF D，由跨膜丝氨酸蛋白酶matriptase激活，诱导骨基质细胞中的旁分泌细胞信号传导，介导骨微环境中前列腺癌生长的关键肿瘤-基质相互作用。为了验证这一假设，我们提出：（1）研究基质蛋白酶介导的PDGF D的蛋白水解过程;（2）使用体外模型RAW 264.7和MC 3 T3-E1细胞系研究PDGF D诱导破骨细胞和成骨细胞分化的分子机制;（3）研究PDGF D及其功能调节因子matriptase在骨基质反应和前列腺肿瘤生长中的作用。考虑到2-PDGFR以及间质蛋白酶在骨转移和原发性前列腺癌标本中高度上调，完成PDGF D（2-PDGFR的特异性激活剂）和间质蛋白酶之间相互作用的拟议研究将有助于我们了解前列腺癌进展的分子基础。此外，拟议的研究可能提供具有治疗价值的重要信息，特别是考虑到VEGF/PDGF抑制剂目前正在癌症患者的临床试验中。 公共卫生相关性：由肿瘤细胞产生的间充质生长因子激活其在周围基质细胞中表达的同源受体，介导肿瘤-基质相互作用。这些相互作用被认为对原发部位和转移部位的肿瘤进展至关重要。绝大多数前列腺癌（PC）转移发生在骨骼部位。PC转移到骨的明显倾向的机制开始被理解。尽管仍有争议，但据信肿瘤细胞产生的细胞表面和分泌因子诱导骨细胞反应，这是骨中PC生长的关键初始步骤。破骨细胞的骨吸收导致骨基质中生长因子和细胞因子的释放，为肿瘤细胞的增殖和侵袭提供了有利的微环境。骨形成伴随或伴随骨破坏，这些骨反应最终变得足够广泛，在X线片上可见硬化和溶解反应。越来越多的证据表明，血小板源性生长因子（PDGF）介导的肿瘤间质的相互作用，在人类前列腺癌骨转移。该项目的目标是研究前列腺癌产生的PDGF启动骨重建的分子机制，骨重建是肿瘤细胞定植到骨的关键事件。在本申请中，我们将测试我们的假设，即肿瘤相关丝氨酸蛋白酶，matriptase，调节新发现的PDGF配体，PDGF D的生物活性，以及肿瘤衍生的PDGF D调节破骨细胞分化以及成骨细胞增殖/分化的肿瘤细胞生长的关键。