Project 1: Inhibition of Complement C5aR1 Radioprotects Normal Tissue and Radiosensitizes Tumors

项目 1：抑制补体 C5aR1 辐射保护正常组织并使肿瘤辐射增敏

• 批准号: 10707880
• 负责人: Amato J. Giaccia
• 金额: $ 22.78万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-21 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10707880
• 关键词: Animal Model; Apoptosis; Attenuated; Cancer Model; Cell Culture Techniques; Cell Survival; Cells; Clinic; Collaborations; Colorectal Cancer; Colorectal Neoplasms; Complement; Complement Receptor; Data; Dependence; Disease; Ensure; Epithelium; Exhibits; Gastrointestinal tract structure; Genetic; Histologic; Immune; Immunity; In Vitro; Interleukin-10; Intestines; Lung; Macrophage; Malignant Neoplasms; Mediating; Methods; Modeling; Molecular; Mus; Natural Immunity; Normal tissue morphology; Pathway interactions; Phosphorylation; Population; Process; Proto-Oncogene Proteins c-akt; Radiation; Radiation Protection; Radiation induced damage; Radiation therapy; Radiation-Sensitizing Agents; Radiosensitization; Role; Salivary Glands; Schedule; Signal Transduction; Site; Small Intestines; Stress; TP53 gene; Therapeutic; Therapeutic Index; Tissues; Toxic effect; Tumor Promotion; Tumor Tissue; angiogenesis; antagonist; cell killing; clinical effect; colon cancer cell line; complement pathway; complement system; crypt cell; data sharing; dosimetry; effectiveness evaluation; gastrointestinal; gastrointestinal epithelium; gastrointestinal system; improved; in vivo; inhibitor; intestinal injury; irradiation; molecular targeted therapies; neoplastic cell; pharmacologic; radiation response; radioprotected; recruit; response; targeted treatment; tumor; tumor progression

Abstract (Project 1 - Oxford) Increasing the therapeutic window of radiotherapy may be achieved by using targeted therapies against cancer- associated pathways. The complement system is an innate immunity pathway, with emerging roles in cancer progression. No study has evaluated the effect of complement inhibition on both tumor and normal tissue radiation response. Here we show that targeting complement receptor C5aR1 improves radiation response in colorectal cancer models while reducing radiation-induced toxicity. Targeting C5aR1 increases IL-10 secretion, which attenuates NF-κB signaling and enhances apoptosis in tumor cells. IL-10-dependent apoptosis is observed both in vivo and in vitro suggesting a non-canonical stress-specific and likely immune-independent role for C5aR1 in regulating apoptosis. Importantly, we find that C5aR1 depletion results in decreased small intestinal histologic damage, crypt cell apoptosis and increased survival of mice following irradiation. In the small intestine, C5aR1 depletion results in increased IL-10 expression in both non-immune and immune cell populations. IL-10 signaling in CX3CR1+ macrophages is important for intestinal injury defense and C5aR1-/- mice have significantly higher levels of CX3CR1+ macrophages than WT mice. In response to irradiation, C5aR1 depletion does not attenuate NF-κB signaling but instead increases AKT activation correlating with decreased apoptosis occurring in an IL-10-depedent manner. Our data, therefore, indicate that genetically or pharmacologically targeting C5aR1 can improve radiation response in colorectal tumor models while reducing radiation-induced small bowel toxicity. Together, these findings suggest that inhibiting complement could be a promising approach to increasing the therapeutic window of radiotherapy. In this Project, we propose four specific aims to better understand the role of C5aR1 in radioprotection and radiosensitization. Aim 1 will determine the broad versus specific protection of normal epithelium (intestines, salivary glands, and lung epithelium) by C5aR1-/- mice in response fractionated and hypofractionated radiotherapy, in collaboration with Projects 2, 3, 4 and Core B. In Aim 2, we will investigate the mechanistic basis of radioprotection when C5aR1 is inhibited. Our preliminary data indicates that this is an IL-10 dependent mechanism and involves recruitment of CX3CR1+ macrophages that promote survival and angiogenesis. Aim 3 will determine how C5aR1 promotes tumor cell killing in combination with radiotherapy. The hypothesis based on our preliminary data is that C5aR1 inhibition increases IL-10 secretion, which attenuates NF-κB signaling, resulting in IL-10 dependent tumor cell killing both in cell culture and in animal models. Aim 4 will determine the effect of clinical grade C5aR1 inhibitors on radioprotecting intestine, salivary glands and lungs, and sensitizing colorectal tumors to radiotherapy. I intend to return to Stanford on a monthly or bimonthly schedule and will share this data with my colleagues at Stanford. At Oxford, we perform our own dosimetry and will cooperate with Core B at Stanford to ensure comparability of methods.

摘要（项目1-牛津） 可以通过使用针对癌症的靶向疗法来实现放射疗法的治疗窗口的增加 相关途径。完成系统是一种先天的免疫途径，在癌症中具有新兴角色 进展。没有研究评估了抑制对肿瘤和正常组织的完成的影响 辐射响应。在这里，我们表明，靶向补体受体C5AR1改善了辐射反应 结直肠癌模型，同时降低辐射诱导的毒性。靶向C5AR1增加IL-10分泌， 这会减弱NF-κB信号传导并增强肿瘤细胞的凋亡。 IL-10依赖性凋亡是 观察到体内和体外都表明非经典应力特异性和可能免疫独立的作用 用于控制凋亡的C5AR1。重要的是，我们发现C5AR1部署导致小肠减少 辐射后，组织学损害，加密细胞凋亡和小鼠的存活率增加。在小肠中， C5AR1的部署导致非免疫和免疫细胞种群中的IL-10表达增加。 IL-10 CX3CR1+巨噬细胞中的信号对于肠损伤防御很重要，C5AR1 - / - 小鼠显着 与WT小鼠相比，CX3CR1+巨噬细胞的水平更高。响应辐照，C5AR1部署没有 减弱NF-κB信号传导，但增加了与凋亡减少相关的Akt激活 以IL-10的方式。因此，我们的数据表明遗传学或药理靶向C5AR1 可以改善结直肠肿瘤模型中的辐射反应，同时减少辐射诱导的小肠毒性。 这些发现共同表明，抑制完成可能是增加增加的方法 放射疗法的治疗窗口。在这个项目中，我们提出了四个特定的目标，以更好地了解角色 辐射保护和放射敏化中的C5AR1。 AIM 1将确定广泛的和特定的保护 C5AR1 - / - 小鼠的正常上皮（肠，唾液腺和肺上皮）以响应分级为单位 与项目2、3、4和核心B合作的降量放疗。在AIM 2中，我们将调查 抑制C5AR1时辐射保护的机械基础。我们的初步数据表明这是 IL-10依赖机制，并涉及促进生存和 血管生成。 AIM 3将确定C5AR1如何与放射疗法结合促进肿瘤细胞杀伤。 基于我们的初步数据的假设是C5AR1抑制增加了IL-10分泌，这 减弱NF-κB信号传导，导致IL-10依赖性肿瘤细胞在细胞培养和动物中均可杀死 AIM 4将确定临床级C5AR1抑制剂对放射性肠，唾液的影响 腺体和肺部，并使结直肠肿瘤对放射疗法敏感。我打算每月返回斯坦福 或每两个月时间表，并将与我在斯坦福大学的同事共享此数据。在牛津，我们自己表演 剂量法并将与斯坦福大学的核心B协调，以确保方法的可比性。