Macrophage and Microglial Activation in Glioma-Associated Inflammation

描述(由申请人提供)：该项目的目标是为申请人纳林·古普塔提供必要的专业知识，通过他以前的经验和培训，在加州大学旧金山分校发展他的独立研究生涯。这将通过以色列·F·查罗博士指导的研究项目以及免疫学和转基因小鼠模型的使用方面的额外培训来实现。古普塔博士是一名儿科神经外科医生，对神经肿瘤学有临床和研究兴趣。他的项目《脑胶质瘤相关炎症中巨噬细胞和小胶质细胞的激活》解决了脑瘤生物学中一个研究不足的方面：炎症细胞和肿瘤细胞之间的相互作用。该项目的假设是巨噬细胞和小胶质细胞通过一种特定的趋化因子--单核细胞趋化蛋白-1(MCP-1)的过度表达而被招募到高级别胶质瘤中，并且这一过程促进了肿瘤的生长。检验这一假说的具体目的是：1)确定肿瘤相关巨噬细胞的来源，2)测量CCR2细胞因子受体缺失对发展为少突胶质瘤的小鼠胶质瘤生长的影响，以及3)确定肿瘤和宿主来源的MCP-1对胶质瘤生长的贡献。MCP-1在高级别胶质瘤中普遍存在，它与浸润性巨噬细胞的相关性，以及支持这种细胞因子在血管生成和肿瘤细胞迁移中的作用的数据表明了MCP-1的重要性。巨噬细胞和小胶质细胞对胶质瘤生长的影响将通过转基因小鼠的遗传学方法直接检测。在Ink4a/arf杂合背景中表达v-erbB癌基因的小鼠发生高级别肿瘤，其发病率是可预测的。这些肿瘤概括了人类高级别肿瘤的许多特征。对于特定的目标1，动物将接受带有荧光标记细胞的骨髓移植，以便能够准确地识别骨髓来源的细胞。在Aim 2中，细胞因子活性对胶质瘤生长的影响将通过将表达v-erbB的小鼠与缺乏CCR2的小鼠杂交来测量，CCR2是MCP-1的细胞受体。巨噬细胞和小胶质细胞将通过免疫组织化学和流式细胞术进行检测。最终目标将使用转化的星形胶质细胞颅内移植来研究肿瘤来源或宿主来源的MCP-1对肿瘤生长的影响。如果达到预期的结果，我们下一步将评估MCP-1/CCR2信号通路的抑制剂作为潜在的抗肿瘤药物。公共卫生相关性：伴随着恶性脑肿瘤的炎症会给患者带来并发症，并可能促进肿瘤的生长。确定炎症在脑瘤中的作用将为开发针对这一过程的药物提供理论基础。这类药物的另一个可能的好处是，与放射等治疗相关的正常组织损伤也可能减少。

DESCRIPTION (provided by applicant): The goal of this project is to provide the applicant, Nalin Gupta, with the necessary expertise to develop an independent research career at the University of California San Francisco by building on his previous experience and training. This will be accomplished through a mentored research project supervised by Dr. Israel F. Charo, and additional training in immunology and use of transgenic mouse models. Dr. Gupta is a pediatric neurosurgeon with a clinical and research interest in neuro-oncology. His project, 'Macrophage and microglial activation in glioma-associated inflammation' addresses an understudied aspect of brain tumor biology: The interactions between inflammatory cells and tumor cells. The hypothesis of this project is that macrophages and microglia are recruited to high-grade gliomas by over-expression of a specific chemokine, monocyte chemoattractant protein-1 (MCP-1), and that this process facilitates tumor growth. The Specific Aims that will test this hypothesis are: 1) determine the origin of tumor-associated macrophages, 2) measure the effect of loss of the CCR2 cytokine receptor on glioma growth in mice developing oligodendrogliomas, and 3) determine the contribution of tumor and host-derived MCP-1 on glioma growth. The importance of MCP-1 is suggested by its ubiquity in high-grade gliomas, its correlation with infiltrating macrophages, and data supporting a role for this cytokine in angiogenesis and tumor cell migration. The effect of macrophages and microglia on glioma growth will be directly examined using a genetic approach in transgenic mice. Mice expressing the v-erbB oncogene in a heterozygous ink4a/arf background develop high-grade tumors with a predictable incidence. These tumors recapitulate many of the features of human high-grade tumors. For Specific Aim 1, animals will receive bone marrow transplants with fluorescently labeled cells so that bone- marrow derived cells can be identified precisely. The effect of cytokine activity upon glioma growth will be measured in Aim 2 by crossing v-erbB expressing mice with mice that lack CCR2, the cellular receptor for MCP-1. Macrophage and microglia will be measured using immunohistochemistry and flow cytometry. The final Aim will use intracranial implantation of transformed astrocytes to study the effect of either tumor- or host-derived MCP-1 on tumor growth. If the expected results are achieved, we would next evaluate inhibitors of the MCP-1/CCR2 signaling pathway as potential anti-tumor agents. Public Health Relevance: Inflammation accompanying malignant brain tumors results in complications for patients, and may promote the growth of tumors. Identifying the role of inflammation in brain tumors would provide a rationale to develop drugs to target this process. Another possible benefit of such drugs is that normal tissue injury associated with treatments such as radiation may also be reduced.