Project-1: Defining the mechanisms by which neurons promote breast cancer metastasis

项目摘要 肿瘤是由癌细胞、浸润性宿主细胞、分泌因子和细胞外组成的异质性群体。 基质蛋白--共同构成肿瘤微环境。肿瘤微环境发挥着深刻的作用 在支持肿瘤的发生、存活、进展和转移中的作用。我们已经发现了那个肿瘤 血管内皮细胞为癌细胞提供了一种“有益的”信号，从而推动了肿瘤的转移。我们找到了Slit2， 轴突引导分子，在转移性肿瘤内的内皮细胞中上调。内皮细胞特异性 Slit2基因缺失对肿瘤转移有明显的抑制作用。在一个令人惊讶的发现中，我们发现内皮细胞Slit2的缺失 也会损害肿瘤的神经。神经才刚刚开始被认为是肿瘤间质中的关键角色， 最近的证据表明，它们对胃癌和前列腺癌的肿瘤启动是必要的。在……里面 乳腺癌，尽管有一些初步证据表明神经支配与肿瘤相关 侵袭性、神经依赖性对转移的影响尚未被探讨。在本项目中，我们将定义角色 研究原发乳腺肿瘤间质中的神经元，并了解神经元如何调节转移。vbl.使用 对同基因细胞系的差异转移潜能、逆行示踪和成像研究，我们将首先鉴定 调节乳腺癌转移的神经元亚群。我们将使用3D共培养系统和活体 去神经实验确定神经元在肿瘤侵袭、增殖、局部和全身中的作用 传播、远距离播种和转移生长。我们还将评估肿瘤神经支配在 乳腺癌的治疗耐药。接下来，我们将使用无偏见的测序方法来定义肿瘤- 营养因子由神经元分泌，并在癌细胞中描绘下游信号轴。最后，我们会 鉴定内皮细胞在引导神经元进入转移性肿瘤中的作用，并确定是否前- 神经元的转移效应部分是由免疫细胞介导的。拟议的跨学科研究计划 结合了分子、遗传、生化、成像和计算方法，建立了一个完整的 乳腺癌转移进展的神经调控模型。总的来说，这些研究将定义 肿瘤内皮细胞、神经元和免疫细胞之间的细胞和分子相互作用 微环境-我们提议的MetNet研究中心的首要目标。这些研究已经 巨大的影响潜力，因为他们将确定扰乱神经肿瘤的新治疗靶点 驱动转移的信号轴。

Project Summary Tumors are a heterogenous population of cancer cells, infiltrating host cells, secreted factors and extracellular matrix proteins–together comprising the tumor microenvironment. The tumor microenvironment plays profound roles in supporting tumor initiation, survival, progression and metastasis. We have discovered that tumor endothelial cells provide an “instructive” signal to cancer cells that drives metastatic progression. We found Slit2, an axon guidance molecule, to be upregulated in endothelial cells within metastatic tumors. Endothelial-specific deletion of Slit2 strongly inhibited metastasis. In a surprising discovery, we found that endothelial-Slit2 deletion also impairs tumor innervation. Nerves are only starting to be recognized as key players within the tumor stroma, with recent evidence demonstrating their requirement for tumor initiation of gastric and prostate cancers. In breast cancer, although there is some preliminary evidence that innervation correlates with tumor aggressiveness, nerve dependence for metastasis has not been explored. In this Project, we will define the role of neurons within the stroma of primary breast tumors and understand how neurons regulate metastasis. Using isogenic cell lines of differential metastatic potential, retrograde tracing and imaging studies, we will first identify neuronal sub-populations that regulate breast cancer metastasis. We will use 3D co-culture systems and in vivo denervation experiments to identify the role of neurons in tumor invasion, proliferation, local and systemic dissemination, distant seeding, and metastatic outgrowth. We will also evaluate the role of tumor innervation in therapeutic resistance in breast cancer. Next, we will use unbiased sequencing approaches to define tumor- trophic factors secreted by neurons and delineate downstream signaling axes in cancer cells. Finally, we will characterize the role of endothelial cells in guiding neurons into metastatic tumors and determine if the pro- metastatic effects of neurons are partly mediated by immune cells. The proposed inter-disciplinary research plan combines molecular, genetic, biochemical, imaging and computational approaches to establish an integrated model for neural regulation of metastatic progression by breast cancer. Collectively, these studies will define the cellular and molecular interactions between endothelial cells, neurons, and immune cells within the tumor microenvironment–an overarching goal of our proposed MetNet research center. These studies have tremendous potential for impact as that they stand to identify novel therapeutic targets that perturb neural-tumoral signaling axes driving metastasis.