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：
8657813
负责人：
William B. Stallcup
金额：
$ 42.33万
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 2016-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8657813
关键词：
Ablation Adipocytes Affect Allografting Basal lamina Blood Circulation Blood Vessels Bone Marrow Transplantation Breast Cancer Treatment 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 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 cancer therapy 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（申请人提供）：NG2蛋白多糖不由乳腺癌MMTV-PyMT小鼠模型中的乳腺肿瘤细胞表达，但由肿瘤基质中至少三种重要的细胞类型表达：肿瘤脉管系统中的周细胞、骨髓细胞从循环系统侵入肿瘤的细胞和乳腺脂肪垫中的脂肪细胞。根据肿瘤潜伏期、生长速度和转移等多个标准，在 MMTV-PyMT 模型中，NG2 的消融大大减缓了乳腺肿瘤的进展，强调了微环境因素在促进肿瘤发生中的力量。由于我们对肿瘤血管化和转移的兴趣，我们重点研究 NG2 支持周细胞和骨髓细胞的肿瘤促进活性的机制。该提案的具体目的是在 MMTV-PyMT 模型中检查周细胞 NG2 和骨髓细胞 NG2 对乳腺肿瘤进展的各自影响。为此，我们将在这两个群体中利用 NG2 的细胞类型特异性消融来分析自发性乳腺肿瘤和同种异体移植乳腺肿瘤的进展。在目标 1 中，我们将比较对照小鼠和通过 NG2 floxed 小鼠与 Pdgfrb/Cre 转基因小鼠杂交产生的周细胞特异性 NG2 null 小鼠的肿瘤进展和肿瘤血管化。肿瘤脉管系统的表征包括确定内皮细胞的周细胞鞘、周细胞和内皮细胞的成熟、基底层的组装、血管通畅、血管渗漏和肿瘤缺氧。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。在目标 2 中，我们将比较对照小鼠和通过 NG2 floxed 小鼠与 LysM/Cre 转基因小鼠杂交产生的骨髓特异性 NG2 null 小鼠的骨髓细胞功能。 NG2 消融效应的表征将包括确定 M1 与 M2 极化、评估关键骨髓细胞群的大小和分化状态的变化，以及将这些细胞群定位到关键部位，例如脉管系统和肿瘤边缘。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。在目标 3 中，我们将使用周细胞特异性和骨髓特异性 NG2 缺失小鼠来研究 NG2 在乳腺肿瘤转移至肺部中的重要性。我们将使用荧光标记的乳腺肿瘤细胞将转移过程分解为各个组成阶段，包括肿瘤细胞内渗到脉管系统、肿瘤细胞从脉管系统外渗到肺部，以及在肺部建立转移前生态位。