BASE TITLE: PREVENT PRECLINICAL DRUG DEVELOPMENT PROGRAM: PRECLINICAL EFFICACY AND INTERMEDIATE ENDPOINT BIOMAKERSTASK ORDER TITLE: VACCINES AGAINS

基本标题：预防临床前药物开发计划：临床前疗效和中间终点 BIOMAKERSTASK 订单标题：再次疫苗

• 批准号: 10651935
• 负责人: MARGIE CLAPPER
• 金额: $ 61.42万
• 依托单位: RESEARCH INST OF FOX CHASE CAN CTR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2023-12-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10651935
• 关键词: APC gene; Adult; Adverse effects; Advisory Committees; African American; Age; American; Anaerobic Bacteria; Animals; Antibiotics; Antigens; ApcMin/+ mice; Bacillus; Bacteria; Bacteroides fragilis; Binding; Biological; COVID-19; Cancer Etiology; Cell physiology; Cell-Mediated Cytolysis; Chemopreventive Agent; Child; Clinical; Codon Nucleotides; Colitis; Colonoscopy; Colorectal; Colorectal Adenoma; Colorectal Cancer; Colorectal Neoplasms; Colorectal Polyp; Containment; DNA; Data; Dental Plaque; Development; Diagnosis; Disease; Distant; Distant Metastasis; Dysplasia; Encapsulated; Enhancers; Epitopes; Familial Adenomatous Polyposis Syndrome; Family history of; Feces; Fusobacteria; Fusobacterium nucleatum; Genetic; Germ-Line Mutation; Goals; Gram-Negative Bacteria; Helicobacter pylori; Hepatitis B Virus; Hereditary Nonpolyposis Colorectal Neoplasms; Human; Human Papilloma Virus Vaccine; ITIM; Immune; Immune Sera; Immunity; Immunoglobulins; Immunosuppression; Incidence; Individual; Infection; Infection prevention; Infectious Agent; Inflammatory Bowel Diseases; Inherited; Innate Immune Response; Intervention; Lead; Lesion; Malignant Neoplasms; Malignant neoplasm of cervix uteri; Malignant neoplasm of gastrointestinal tract; Measures; Mediating; Membrane; Messenger RNA; Methodology; Microsatellite Instability; Mismatch Repair; Mismatch Repair Deficiency; Modeling; Modification; Morbidity - disease rate; Natural Killer Cells; Neoplasm Metastasis; Non-Insulin-Dependent Diabetes Mellitus; Nonsense Mutation; Obesity; Oncogenic; Operative Surgical Procedures; Oral; Organ; Patients; Phase; Population; Preclinical Drug Development; Prevalence; Preventive; Preventive measure; Preventive service; Preventive vaccine; Primary carcinoma of the liver cells; Program Development; Proteins; Proteomics; Pseudouridine; RNA; RNA vaccine; Race; Recommendation; Recording of previous events; Regimen; Regulatory T-Lymphocyte; Reporter; Resistance; Risk; Risk Factors; Role; Small Intestinal Neoplasm; Survival Rate; Syndrome; System; T-Lymphocyte; Time; Tissues; Tumor Escape; United States; United States National Library of Medicine; Update; Vaccination; Vaccine Antigen; Vaccines; Vesicle; Virulence Factors; Wild Type Mouse; adenoma; aged; base; biomaterial compatibility; cancer risk; cigarette smoking; colorectal cancer risk; colorectal cancer screening; coronavirus disease; design; draining lymph node; effector T cell; efficacy testing; gene repair; glycerophosphodiester phosphodiesterase; immunogenic; immunogenicity; improved; in vivo; infection rate; lipid nanoparticle; malignant breast neoplasm; malignant stomach neoplasm; microbiota; mortality; mouse model; mutation carrier; neoplastic cell; pathogen; preclinical efficacy; premalignant; prevent; prophylactic; receptor; scale up; screening; tumor; tumor growth; tumor microenvironment; tumorigenesis; tumorigenic; vaccine platform; vaccinology

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality worldwide. In the Unites States, an estimated 151,300 Americans will be diagnosed with CRC and over 52,580 are expected to die from the disease in 2022 alone (https://seer.cancer.gov/statfacts/html/colorect.html). While the five-year survival rate for localized CRC is excellent at 90%, more than half of new CRC cases have the disease spread to regional lymph nodes and/or distant organs at the time of diagnosis. CRC with distant metastasis has a dismal five-year survival rate of 14.7%. These data clearly indicate that CRC-related mortality can be significantly improved if the disease is detected early and proper interventions could be deployed. Because CRC typically originates from precancerous colorectal polyps, routine colonoscopy screening provides an excellent opportunity to detect precursor or early lesions and reduce CRC-related morbidity and mortality. Indeed, the US Preventive Services Task Force recently updated its recommendation on CRC screening, noting the evidence that the screening in average-risk asymptomatic adults aged 50 to 75 years is of substantial benefit. Risk factors for CRC include age (>50), race (African American), obesity, cigarette smoking, type II diabetes, history of inflammatory bowel diseases, family history of colorectal polyps or CRC, and inherited genetic syndromes known to increase the CRC risks, such as familial adenomatous polyposis (FAP) and Lynch syndrome. FAP and Lynch syndrome are caused by germline mutations in the APC gene and DNA mismatch repair genes, respectively. The management of individuals with hereditary gastrointestinal cancer syndromes requires additional measures beyond what is recommended for the average-risk population to minimize the overall risk of cancer-associated morbidity and mortality. Management options for the confirmed mutation carriers include multiple aggressive screening, chemopreventive strategies, and prophylactic surgery. However, these interventions are associated with various degrees of adverse effects. Safer and more effective preventive measures are urgently needed for the individuals with FAP, Lynch syndrome, and other hereditary gastrointestinal cancer syndromes. Fusobacteria are common human oral gram-negative anaerobic microflora isolated from dental plaque and gum diseases, but rarely detectable in the colorectum of healthy individuals. In recent years, the enrichment of a specific pathotype, Fusobacterium nucleatum (Fn), has been demonstrated in the colonic tissues and stools from patients with colorectal adenomas and CRC. Clinical evidence suggests that the prevalence of Fn progressively increases from dysplasia, adenomas to CRC and the higher amount of Fn is significantly associated with CRC with high microsatellite instability, which is caused by DNA MMR deficiencies as seen in Lynch syndrome-associated CRC. The potential association of Fn with CRC tumorigenesis has been examined in a mouse model of FAP. ApcMin/+ mice, which carry a nonsense mutation at codon 850 of the Apc gene, had a significantly accelerated onset and increased multiplicity of both small intestinal and colorectal tumors after oral inoculation of Fn. These data strongly suggested the tumor-promoting role of Fn in ApcMin/+ mice. Interestingly, Fn did not induce colitis in these animals, in contrast to enterotoxigenic Bacteroides fragilis, which has been shown to cause colitis and accelerate tumorigenesis in ApcMin/+ mice. It has also been demonstrated that Fn promotes CRC, breast, and cervical cancer metastasis and can metastasizes with tumor cells. Although how Fn contributes to CRC tumorigenesis has yet to be fully elucidated, emerging evidence points to its virulence factors, such as FadA and Fap2, as potential enhancers of CRC tumorigenesis and progression. The Fap2 has been shown to bind to human T-cell immunoglobulin ITIM domain (TIGIT), an immunoglobulin superfamily receptor known to function as an immune co-inhibitory molecule. Fap2-binding to TIGIT on NK and other T cells protects tumor cells from NK cell-mediated cytotoxicity and blocks effector T cell functions in the tumor microenvironment. TIGIT has also been shown to promote Treg function. Taken together, Fn may exert tumor promoting effects not only by promoting CRC tumor growth, but also by exploiting the immune-suppressive function of TIGIT via its virulence factor protein and contributing to tumor immune evasion mechanisms. Cancers caused by infectious agents are theoretically preventable, if one can prevent the infection, eradicate oncogenic pathogens before tumor development, or suppress the functions of oncogenic molecules. Prophylactic vaccines for human papillomavirus and hepatitis B virus have been associated with significant reductions in infection rates, which are expected to result in the dramatic decrease in the incidence of cervical cancers and hepatocellular carcinoma, respectively. Compared to the prevention of infection, the eradication of oncogenic infectious agents already colonized in the host is in general highly challenging, if not impossible. For example, the well-established eradication regimens for Helicobacter pylori, which increases the risk of noncardia gastric cancers, do not eradicate the bacteria in all cases. Rather, emerging resistance to multiple antibiotics appears to be contributing to the recent decline in the eradication rate. Alternatively, the host immune defense system may be fortified by pathogen-targeted vaccines, if they can boost anti-pathogen immunity and lead to the containment of infection or suppression of pathogen-mediated tumorigenic functions. Fn is a gram-negative anaerobic bacillus, and can be isolated from 60-70% of children aged 5-7 years. As with other gram-negative bacteria, Fn produces outer membrane vesicles (OMVs), which contain much of the biological content of the Fn, but without replicative capacity and some of the soluble proteins found in OMVs may elicit anti-Fn immunity. As part of the PREVENT project to develop Fn OMV based anti-Fn vaccine (https://reporter.nih.gov/project-details/9358850), the proteomic characterization of Fn OMV led to the identification of putative immunogenic components, some of which may be useful as anti-Fn vaccine antigens. Lipid nanoparticle (LNP)-encapsulated mRNA vaccines against COVID-19 revolutionized the implementation of mRNA-based vaccinology. In addition to modifications of mRNA such as with pseudouridine incorporation to reduce innate immune responses and mRNA purification methodologies to remove contaminants, the development of biocompatible LNPs significantly boosted the advancement of COVID and other mRNA-based vaccines. LNP-RNA vaccine platform offers several advantages over conventional protein-based vaccination, including a rapid development, refined adjustment of antigenic epitopes, easier scale-up and timely deployment. The the current study aims to develop and evaluate the immunogenicity of soluble protein-based and LNP-RNA-based Fn vaccines and to determine anti-Fn activity and immunopreventive efficacy of Fn-associated CRC, using mouse models of FAP and Lynch syndrome.

结直肠癌（CRC）是全球癌症相关死亡的主要原因之一。在美国，估计将有 151,300 名美国人被诊断出患有 CRC，仅 2022 年预计就有超过 52,580 人死于该疾病 (https://seer.cancer.gov/statfacts/html/colorect.html)。虽然局限性 CRC 的五年生存率高达 90%，但超过一半的新 CRC 病例在诊断时疾病已经扩散到区域淋巴结和/或远处器官。伴有远处转移的结直肠癌的五年生存率仅为 14.7%。这些数据清楚地表明，如果及早发现疾病并采取适当的干预措施，则与结直肠癌相关的死亡率可以显着降低。由于结直肠癌通常起源于癌前结直肠息肉，因此常规结肠镜检查为检测癌前病变或早期病变并降低结直肠癌相关发病率和死亡率提供了绝佳的机会。事实上，美国预防服务工作组最近更新了关于 CRC 筛查的建议，指出有证据表明，对 50 至 75 岁的平均风险无症状成年人进行筛查具有显着益处。 CRC 的危险因素包括年龄 (>50)、种族（非裔美国人）、肥胖、吸烟、II 型糖尿病、炎症性肠病史、结直肠息肉或 CRC 家族史以及已知会增加 CRC 风险的遗传综合征，例如家族性腺瘤性息肉病（FAP）和林奇综合征。 FAP 和 Lynch 综合征分别是由 APC 基因和 DNA 错配修复基因的种系突变引起的。对患有遗传性胃肠癌综合征的个体的管理需要超出平均风险人群建议的额外措施，以最大限度地降低癌症相关发病率和死亡率的总体风险。对于已确诊的突变携带者的治疗选择包括多重积极筛查、化学预防策略和预防性手术。然而，这些干预措施会带来不同程度的不良反应。对于患有FAP、林奇综合征和其他遗传性胃肠癌综合征的个体来说，迫切需要更安全、更有效的预防措施。 梭杆菌是从牙菌斑和牙龈疾病中分离出来的常见人类口腔革兰氏阴性厌氧微生物群，但在健康个体的结肠直肠中很少检测到。近年来，已证明结直肠腺瘤和结直肠癌患者的结肠组织和粪便中富集了一种特定的致病型——具核梭杆菌（Fn）。临床证据表明，Fn 的患病率从不典型增生、腺瘤到 CRC 逐渐增加，较高的 Fn 量与具有高微卫星不稳定性的 CRC 显着相关，这是由 DNA MMR 缺陷引起的，如 Lynch 综合征相关 CRC 中所见。 Fn 与 CRC 肿瘤发生的潜在关联已在 FAP 小鼠模型中进行了研究。 ApcMin/+ 小鼠在 Apc 基因的密码子 850 处携带无义突变，在口服 Fn 后，小肠和结直肠肿瘤的发病速度显着加快，且其多重性增加。这些数据强烈表明 Fn 在 ApcMin/+ 小鼠中具有促肿瘤作用。有趣的是，Fn 不会在这些动物中诱发结肠炎，这与产肠毒素脆弱拟杆菌相反，后者已被证明会在 ApcMin/+ 小鼠中引起结肠炎并加速肿瘤发生。研究还表明，Fn 可促进结直肠癌、乳腺癌和宫颈癌的转移，并可随肿瘤细胞一起转移。 尽管 Fn 如何促进 CRC 肿瘤发生尚未完全阐明，但新的证据表明其毒力因子（例如 FadA 和 Fap2）是 CRC 肿瘤发生和进展的潜在促进剂。 Fap2 已被证明可以与人 T 细胞免疫球蛋白 ITIM 结构域 (TIGIT) 结合，TIGIT 是一种免疫球蛋白超家族受体，已知具有免疫共抑制分子的功能。 Fap2 与 NK 和其他 T 细胞上的 TIGIT 结合，可保护肿瘤细胞免受 NK 细胞介导的细胞毒性的影响，并阻断肿瘤微环境中的效应 T 细胞功能。 TIGIT 也被证明可以促进 Treg 功能。综上所述，Fn不仅可以通过促进CRC肿瘤生长发挥促癌作用，还可以通过其毒力因子蛋白利用TIGIT的免疫抑制功能并促进肿瘤免疫逃避机制。 如果能够预防感染、在肿瘤发展前根除致癌病原体或抑制致癌分子的功能，那么从理论上讲，由感染因子引起的癌症是可以预防的。人乳头瘤病毒和乙型肝炎病毒的预防性疫苗与感染率的显着降低有关，预计这将分别导致宫颈癌和肝细胞癌的发病率显着降低。与预防感染相比，根除已经在宿主体内定植的致癌感染因子即使不是不可能，通常也是极具挑战性的。例如，虽然幽门螺杆菌会增加非贲门性胃癌的风险，但行之有效的根除方案并不能在所有情况下根除幽门螺杆菌。相反，对多种抗生素的新出现的耐药性似乎导致了最近根除率的下降。 或者，如果病原体靶向疫苗能够增强抗病原体免疫力并导致遏制感染或抑制病原体介导的致瘤功能，则可以通过病原体靶向疫苗来强化宿主免疫防御系统。 Fn是一种革兰氏阴性厌氧杆菌，可从60-70%的5-7岁儿童中分离到。与其他革兰氏阴性细菌一样，Fn 产生外膜囊泡 (OMV)，其中含有 Fn 的大部分生物成分，但没有复制能力，并且 OMV 中发现的一些可溶性蛋白质可能会引发抗 Fn 免疫。作为开发基于 Fn OMV 的抗 Fn 疫苗的 PREVENT 项目的一部分 (https://reporter.nih.gov/project-details/9358850)，Fn OMV 的蛋白质组表征导致了推定免疫原性成分的鉴定，其中一些其可用作抗-Fn疫苗抗原。 针对 COVID-19 的脂质纳米颗粒 (LNP) 封装的 mRNA 疫苗彻底改变了基于 mRNA 的疫苗学的实施。除了对 mRNA 进行修饰（例如掺入假尿苷以减少先天免疫反应和通过 mRNA 纯化方法去除污染物）之外，生物相容性 LNP 的开发还显着促进了新冠病毒和其他基于 mRNA 的疫苗的进步。 LNP-RNA疫苗平台与传统的基于蛋白质的疫苗接种相比具有多种优势，包括快速开发、抗原表位的精细调整、更容易扩大规模和及时部署。目前的研究旨在使用 FAP 和 Lynch 综合征小鼠模型开发和评估基于可溶性蛋白和 LNP-RNA 的 Fn 疫苗的免疫原性，并确定 Fn 相关 CRC 的抗 Fn 活性和免疫预防功效。