Non-canonical Notch1 regulation of proliferation and adherens junctions in breast cancer

项目摘要 对人类乳腺肿瘤的全基因组测序揭示了这种显著的分子异质性 疾病。然而，个性化乳腺癌治疗的进步需要更多的理解 具体的基因改变如何有助于细胞行为的发生和发展 乳腺癌的风险。我们最近发现了Notch1受体的一种新的、不依赖转录的功能 在调控乳腺上皮细胞增殖和粘连连接组织方面。这项建议将利用 一种将3D组织工程化人类乳房导管平台与 分子和遗传学工具剖析癌症增殖信号通路，并将建立以前的 乳腺癌中未被描述的肿瘤抑制Notch1通路。在K99阶段(目标1)，我们将确定 Notch1在乳腺黏附连接和转录非依赖性调控中的结构域特异性作用 皮质细胞骨架，由这种非规范的Notch1信号控制的信号和增殖途径， 并证明了转录非依赖性NOTCH1功能丧失在乳腺癌异种移植中的作用 模特们。在R00阶段，我们将在乳腺的背景下框定抑制肿瘤的Notch1功能 接触抑制增殖并确定Notch1的分子机制和机制 在乳腺组织生长过程中在粘连连接处激活(目标2)。同时，我们将进一步利用我们的 仿生乳腺导管模型探讨两种主要复发乳腺的不同形态发生表型 研究癌症突变，并测试临床活性药物在肿瘤进展的每个阶段的疗效(目标3)。 这项拟议的研究将确定NOTCH1功能缺失突变对人类乳腺癌的影响 具有这种突变的患者的治疗靶点，并建立一种新的乳腺癌模型策略 3D仿生培养中的治疗进展和评估。我将接受微流控技术的研究培训， 体外组织工程，以及癌症信号、病理学和体内小鼠模型，而 同时通过赠款撰写、指导和领导力方面的培训促进职业发展。我 我组建了一个出色的、互为补充的指导团队，帮助我实现我的研究和职业生涯 目标：器官组织建模和细胞力学方面的专家克里斯托弗·陈博士将是我的主要导师 安德里亚·麦克莱奇博士(麻省理工学院癌症中心/哈佛大学)，细胞骨架调控方面的国际领导者 肿瘤发生、肿瘤抑制信号和癌症模型，将是我的共同导师。体制上的 波士顿大学生物设计中心提供的环境非常适合这项提议， 为生物学家、临床医生和工程师之间的科学讨论和协作提供机会，以及 职业发展。总之，拟议的学习和职业发展培训将确保我实现我的 建立一个成功的、独立资助的研究组织潜在机制的实验室的目标 形态发生和肿瘤发生。

Project Summary Genome-wide sequencing of human breast tumors has revealed the remarkable molecular heterogeneity of the disease. However, the advancement of personalized breast cancer therapies requires a greater understanding of how specific genetic alterations contribute to the cellular behaviors that underlie the onset and development of breast cancer. We have recently identified a novel, transcription-independent function of the Notch1 receptor in the regulation of mammary epithelial proliferation and adherens junction organization. This proposal will utilize an interdisciplinary approach that combines a 3D tissue engineered human mammary duct platform with molecular and genetic tools to dissect cancer proliferative signaling pathways and will establish a previously undescribed, tumor suppressive Notch1 pathway in breast cancer. During the K99 phase (Aim 1), we will identify domain-specific roles of Notch1 in the transcription-independent regulation of mammary adherens junctions and cortical cytoskeleton, the signaling and proliferative pathways controlled by this non-canonical Notch1 signaling, and demonstrate the effects of transcription-independent NOTCH1 loss-of-function in breast cancer xenograft models. During the R00 phase, we will frame tumor suppressive Notch1 function in the context of mammary contact inhibition of proliferation and identify the molecular mechanisms and mechanics by which Notch1 is activated at adherens junctions during mammary tissue growth (Aim 2). In parallel, we will further leverage our biomimetic mammary duct model to explore to the distinct morphogenic phenotypes of two major recurring breast cancer mutations and test the efficacy of clinically active drugs at each stage of their tumor progression (Aim 3). The proposed research will define effects of NOTCH1 loss-of-function mutations in human breast cancer, inform therapeutic targets in patients harboring such mutations, and establish a new strategy to model breast cancer progression and assess therapies in 3D biomimetic cultures. I will gain research training in microfluidic-based, in vitro tissue engineering, as well as cancer signaling, pathology, and in vivo mouse modeling, while simultaneously enhancing career development through training in grant writing, mentoring, and leadership. I have assembled an exceptional, complementary mentoring team to help me achieve my research and career goals: Dr. Christopher Chen, expert in organotypic tissue modeling and cell mechanics, will be my primary mentor and Dr. Andrea McClatchey (MGH Cancer Center/Harvard), an international leader in cytoskeletal regulation of tumorigenesis, tumor suppressor signaling, and cancer modeling, will be my co-mentor. The institutional environment provided by the Biological Design Center at Boston University is ideally suited for this proposal and offers opportunities for scientific discussion, collaboration between biologists, clinicians, and engineers, and career development. Together, the proposed studies and career development training will ensure I achieve my goal of establishing a successful, independently-funded laboratory studying underlying mechanisms of tissue morphogenesis and tumorigenesis.