NG2-PG in tumor vascularization and progression

NG2-PG 在肿瘤血管化和进展中的作用

基本信息

批准号：
9263044
负责人：
William B. Stallcup
金额：
$ 6.1万
依托单位：
SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-04-01 至 2017-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9263044
关键词：
Ablation Adipocytes Affect Allografting Basal lamina Blood Circulation Blood Vessels Bone Marrow Transplantation Breast Cancer Treatment Breast Cancer therapy CSPG4 gene Cell Communication Cell Maturation Cell physiology Cells Coculture Techniques Cultured Tumor Cells Elements Endothelial Cells Extravasation Fatty acid glycerol esters Genetic Growth Hypoxia In Vitro Invaded Knockout Mice Label LoxP-flanked allele Lung Mammary Neoplasms Mammary gland Metastatic Neoplasm to the Lung Modeling Mouse Mammary Tumor Virus Mus Myelogenous Myeloid Cells NG2 antigen Neoplasm Metastasis Pericytes Population Process Property Proteoglycan Radiation therapy Regimen Resistance Role Site Staging Stromal Cells Therapeutic Transgenic Mice Vascularization Work cell assembly cell type in vitro Model in vivo interest intravenous injection macrophage malignant breast neoplasm metastatic process mouse model neoplastic cell offspring tumor tumor progression tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): The NG2 proteoglycan is not expressed by mammary tumor cells in the MMTV-PyMT mouse model of breast cancer, but is expressed by at least three important cell types in the tumor stroma: pericytes in the tumor vasculature, myeloid cells that invade the tumors from the circulation, and adipocytes in the mammary fat pad. By several criteria, including tumor latency, growth rate, and metastasis, ablation of NG2 greatly slows mammary tumor progression in the MMTV-PyMT model, emphasizing the power of microenvironmental factors in promoting tumorigenesis. Due to our interest in tumor vascularization and metastasis, we are focusing on mechanisms by which NG2 supports the tumor-promoting activities of pericytes and myeloid cells. The specific aims of this proposal will be to examine the respective effects of pericyte NG2 and myeloid cell NG2 on mammary tumor progression in the MMTV-PyMT model. For these purposes we will utilize cell type-specific ablations of NG2 in these two populations to analyze the progression of both spontaneous and allografted mammary tumors. In Aim 1 we will compare tumor progression and tumor vascularization in control mice and in pericyte-specific NG2 null mice produced by crossing NG2 floxed mice with Pdgfrb/Cre transgenic mice. Characterization of the tumor vasculature will include determinations of pericyte ensheathment of endothelial cells, maturation of pericytes and endothelial cells, assembly of the basal lamina, vessel patency, vessel leakiness, and tumor hypoxia. In vitro co-cultures of pericytes and endothelial cells will be used to further elucidate mechanisms by which NG2 supports pericyte/endothelial cell crosstalk. In Aim 2 we will compare myeloid cell function in control mice and in myeloid-specific NG2 null mice produced by crossing NG2 floxed mice with LysM/Cre transgenic mice. Characterization of the effects of NG2 ablation will include determination of M1 versus M2 polarization, assessment of changes in the size and differentiation state of key myeloid populations, and localization of these populations to critical sites such as vasculature and tumor margins. In vitro co-cultures of tumor cells and macrophages will be used to explore mechanisms by which NG2 affects macrophage/tumor cell interaction. In Aim 3 we will use both the pericyte-specific and myeloid-specific NG2 null mice to study the importance of NG2 in mammary tumor metastasis to the lungs. We will use fluorescent-labeled mammary tumor cells to dissect the metastatic process into its component stages, including intravasation of tumor cells into the vasculature, extravasation of tumor cells from the vasculature into the lungs, and establishment of pre-metastatic niches in the lungs.

描述（由申请人提供）：NG2蛋白聚糖在MMTV-PYMT小鼠的乳腺癌模型中未表达NG2蛋白聚糖，但由肿瘤基质中的至少三种重要细胞类型表达：肿瘤脉管周围的周细胞，髓样细胞中的髓样细胞，从循环中肿瘤和Adipocococytes中的肿瘤中的肿瘤粉刷为妈妈妈妈的妈妈。根据几个标准，包括肿瘤潜伏期，生长速率和转移，NG2的消融大大减慢了MMTV-PYMT模型中的乳腺肿瘤进展，从而强调了微环境因素在促进肿瘤发生中的能力。由于我们对肿瘤血管化和转移的兴趣，我们专注于NG2支持周细胞和髓样细胞的肿瘤活性的机制。该提案的具体目的是检查周细胞NG2和髓样细胞NG2对MMTV-PYMT模型中乳腺肿瘤进展的各自影响。为了这些目的，我们将利用这两个种群中NG2的细胞类型特异性消融来分析自发和同种异体乳腺肿瘤的进展。在AIM 1中，我们将比较通过将NG2 Floxed小鼠与PDGFRB/CRE转基因小鼠交叉产生的对照小鼠和周细胞特异性NG2 NULL小鼠中的肿瘤进展和肿瘤血管化。肿瘤脉管系统的表征将包括确定内皮细胞周围环境，周细胞和内皮细胞的成熟，基础层的组装，血管通畅，血管泄漏和肿瘤缺氧。周细胞和内皮细胞的体外共培养将用于进一步阐明NG2支持周细胞/内皮细胞串扰的机制。在AIM 2中，我们将比较通过将NG2 Floxed小鼠与LYSM/CRE转基因小鼠交叉产生的对照小鼠和髓样特异性NG2 NULL小鼠中的髓样细胞功能。 NG2消融作用的表征将包括确定M1与M2极化，评估关键髓样人群的大小和分化状态的变化，以及将这些种群定位到诸如脉管系统和肿瘤边缘等关键部位。肿瘤细胞和巨噬细胞的体外共培养将用于探索NG2影响巨噬细胞/肿瘤细胞相互作用的机制。在AIM 3中，我们将使用周细胞特异性和髓样特异性NG2无效小鼠研究NG2在乳腺肿瘤转移中对肺的重要性。我们将使用荧光标记的乳腺肿瘤细胞将转移过程剖分为其成分阶段，包括将肿瘤细胞侵入到脉管系统中，将肿瘤细胞从脉管系统中渗入肺部和肺部的建立。