Investigating the metabolic regulation of tumor desmoplasia

项目摘要/摘要 成纤维细胞合成细胞外基质(ECM)蛋白的能力对伤口愈合至关重要；然而， 这一方案是由多种实体肿瘤中的癌细胞共同作用，导致形成与癌症相关的 成纤维细胞(CAF)，驱动促结缔组织增生反应，从而促进癌症进展和促进 治疗抵抗。胶原是细胞外基质中含量最丰富的蛋白质，具有独特的氨基酸组成。 使得高达25%ITS序列由脯氨酸表示。脯氨酸是胶原蛋白的限制性代谢物 CAF的合成，CAF通过增加线粒体谷氨酰胺分解和促进脯氨酸的生物合成 将产生的谷氨酸引导到脯氨酸的生物合成途径中，而不是将其用作厌食剂 三氯乙烷循环的底物。然而，指导谷氨酰胺差异化利用脯氨酸的机制 或者，人们不理解三氯乙烷循环。此外，谷氨酰胺在许多实体肿瘤中都是耗尽的，比如胰腺肿瘤。 导管腺癌(PDAC)，但矛盾的是，胶原蛋白在PDAC中高度丰富。该计划的目标是 目前的建议是为了更好地了解胶原蛋白产生的独特代谢需求 从而确定减少肿瘤间质增生的新靶点。拟议的研究旨在 确定CAF如何将谷氨酰胺重定向到脯氨酸生物合成(目标1)并确定适应性 当细胞外谷氨酰胺受到限制时，CAF维持胶原产生的机制(目标2)。最后， 我将研究以这些适应机制为目标是否是减少PDAC促结缔组织发育不良的策略 而不影响健康组织中基质的产生(目标3)。从这些研究中获得的科学知识 以及我的研究培训计划将帮助我制定一个独特的研究计划，并促进过渡 走向独立，长期目标是研究肿瘤间质串扰的机制基础，并 应用这些知识来开发可以改善癌症患者预后的治疗策略。此外 为了我的研究目标，我概述了一个详细的职业发展计划，这将帮助我获得重要的 领导独立研究实验室的技能，包括教学和指导技能，科学 通信、补助金撰写和实验室管理。我会在导师的指导下朝着我的目标努力 克雷格·汤普森博士是癌症新陈代谢领域的领导者，他在受训人员中的记录非常出色，后来 教职员工职位。此外，我还组建了一个咨询委员会，该委员会将与我合作并与我会面。 定期帮助我进行拟议的实验，并发展成为一名独立的研究人员。这支队伍 包括在代谢组学方面有专长的贾斯汀·克罗斯博士，在小鼠模型方面有专长的斯科特·洛博士 癌症，乔舒亚·拉比诺维茨博士擅长研究体内代谢流，吉娜·西泽莫尔博士 在研究肿瘤-间质相互作用方面的专业知识。我的研究和职业发展计划，连同我的 纪念斯隆·凯特琳癌症中心的导师、顾问和卓越的学术环境将 提供了坚实的基础，我可以在此基础上建立一个独立的癌症新陈代谢研究人员的职业生涯。

PROJECT SUMMARY/ABSTRACT The ability of fibroblasts to synthesize extracellular matrix (ECM) proteins is critical for wound healing; however, this program is coopted by cancer cells in multiple solid tumors, resulting in the formation of cancer-associated fibroblasts (CAFs) that drive a desmoplastic response which contributes to cancer progression and promotes therapy resistance. Collagen is the most abundant protein in the ECM and has a unique amino acid composition such that up to 25% of its sequence is represented by proline. Proline is a limiting metabolite for collagen synthesis in CAFs, and CAFs promote proline biosynthesis by increasing mitochondrial glutaminolysis and directing the resulting glutamate into the proline biosynthetic pathway instead of its utilization as an anaplerotic substrate for the TCA cycle. However, the mechanism directing the differential utilization of glutamine for proline or the TCA cycle is not understood. Besides, glutamine is depleted in many solid tumors such as pancreatic ductal adenocarcinoma (PDAC), but paradoxically, collagen is highly abundant in PDAC. The objective of the present proposal is to gain a better understanding of the unique metabolic requirements for collagen production in CAFs and thereby identify novel targets to reduce tumor desmoplasia. The proposed studies are aimed at determining how CAFs redirect glutamine into proline biosynthesis (Aim 1) and identifying the adaptive mechanisms by which CAFs sustain collagen production when extracellular glutamine is limited (Aim 2). Finally, I will investigate whether targeting these adaptive mechanisms is a strategy to reduce desmoplasia in PDAC without affecting matrix production in healthy tissues (Aim 3). The scientific knowledge gained from these studies as well as my research training plan will help me to develop a unique research program and facilitate transition into to independence, with the long-term goal to study the mechanistic basis of tumor-stroma crosstalk and to apply this knowledge to develop therapeutic strategies that can improve outcomes of cancer patients. In addition to my research objectives, I have outlined a detailed career development plan that will help me obtain important skills for leading an independent research laboratory, including teaching and mentoring skills, scientific communications, grant writing and laboratory management. I will work towards my goals under the mentorship of Dr. Craig Thompson, a leader in cancer metabolism with a stellar track record of trainees that went on to faculty positions. In addition, I have assembled an Advisory Committee that will collaborate and meet with me regularly to help me perform the proposed experiments and develop into an independent researcher. This team includes Dr. Justin Cross with expertise in metabolomics, Dr. Scott Lowe with expertise in mouse models of cancer, Dr. Joshua Rabinowitz with expertise in studying metabolic flux in vivo, and Dr. Gina Sizemore with expertise in studying tumor-stroma interactions. My research and career development plan, together with my mentor, advisors and the exceptional academic environment at Memorial Sloan Kettering Cancer Center will provide a solid ground on which I can build a career as an independent investigator in cancer metabolism.