Development and Testing of Recombinant Clostridia for Cancer Therapy

用于癌症治疗的重组梭菌的开发和测试

• 批准号: 7800584
• 负责人: JOHN MARTIN BROWN
• 金额: $ 17.98万
• 依托单位: SGM BIOTECH, INC.
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-30 至 2011-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7800584
• 关键词: Alkylating Agents; Animals; Antineoplastic Agents; Area; Bacteria; Cells; Chromosomes; Clinical; Clostridium; Codon Nucleotides; Development; Drug Delivery Systems; Engineering; Enzymes; Escherichia coli; Funding; Genes; Genome; Germination; Goals; Growth; Human; Hypoxia; Injection of therapeutic agent; Laboratories; Modeling; Mus; Necrosis; Nitroreductases; Normal tissue morphology; Organism; Oxygen; Patients; Pharmaceutical Preparations; Phase; Prodrugs; Production; Recombinants; Reproduction spores; Rodent; Safety; Small Business Technology Transfer Research; Solid Neoplasm; System; Technology; Testing; Toxic effect; Toxicology; Universities; cancer therapy; chemotherapeutic agent; cytotoxic; design; efficacy testing; killings; meetings; pathogenic bacteria; prevent; public health relevance; research clinical testing; tumor

DESCRIPTION (provided by applicant): This STTR application is to develop and test for eventual clinical use a new strategy for tumor specific anticancer drug delivery. The technology, Clostridia-directed enzyme prodrug therapy, or CDEPT, exploits the fact that certain non-pathogenic bacteria of the Clostridia genus, which only grow in the absence of oxygen (hypoxia), colonize the hypoxic and necrotic areas that are unique to solid tumors. Growth of these bacteria in these areas can be exploited by engineering the bacteria to produce an enzyme, not normally present in humans that will convert a non-toxic "prodrug" into a toxic drug. Following i.v. injection of spores of the recombinant clostridia, germination of the spores and production of the prodrug activating enzyme occurs solely in the tumors. Since the enzyme is only in the tumor, the prodrug is converted to the toxic drug only in the tumor, hence targeting the cytotoxic activity of the drug selectively to the tumor. We will use a Clostridial species, C. sporogenes, that has been shown (in its non-engineered state) to be well tolerated in human patients, and a new anticancer drug, PR-104, which has recently entered clinical testing and which is highly toxic to cells when it is metabolized by the E. coli nitroreductase (NTR) enzyme (the enzyme that we have engineered C. sporogenes to express). We have demonstrated the efficacy of the combination of our C. sporogenes expressing NTR with PR-104 in rodent tumor models. Our overall goal in this STTR is to combine the expertise of SGM Biotech, which has manufactured C. sporogenes spores under GMP conditions for the past 15 years, with the Brown laboratory at Stanford University, which has genetically engineered C. sporogenes for the CDEPT strategy, to develop the organism for eventual clinical testing. We have three specific aims to achieve this goal: 1) Integrate the Clostridial codon optimized E. coli NTR gene into the genome of C. sporogenes (Stanford University). 2) Produce the recombinant C. sporogenes with the integrated E. coli NTR gene in sufficient quantities to conduct the initial safety and efficacy studies at Stanford University (SGM Biotech), and 3) Test the expression and efficacy (with PR-104) of the GMP produced recombinant C. sporogenes with tumor bearing mice (Stanford University). This project, if successful, will enable clinical testing of the specific delivery of a cytotoxic chemotherapeutic agent to solid tumors in patients thereby enhancing antitumor activity and minimizing normal tissue toxicity. PUBLIC HEALTH RELEVANCE: This STTR proposal presents a unique strategy for targeting effective killing concentrations of a specific chemotherapeutic agent to solid tumors. The approach we are proposing prevents indirect toxic effects on the animal as a whole, but allows for killing concentrations of the drug to be achieved specifically in the tumor, as we are directly activating the drug only in the tumors.

描述（由申请人提供）：此STTR应用是为了开发和测试最终的临床使用新策略，用于肿瘤特异性抗癌药物的递送。 该技术是梭状芽胞杆菌前药治疗或CDEPT的技术，它利用了以下事实：梭状芽胞杆菌属的某些非致病细菌仅在没有氧气（低氧）的情况下生长，在缺氧和坏死区域定位，这些区域是实体肿瘤所独有的。 可以通过工程细菌生产一种酶来利用这些细菌在这些区域的生长，通常不存在于人类中，这种酶会将无毒的“药物”转化为有毒药物。 遵循I.V.注射重组梭状芽胞杆菌的孢子，孢子的发芽和前药激活酶的产生仅发生在肿瘤中。 由于酶仅在肿瘤中，因此前药仅在肿瘤中转化为有毒药物，因此将药物的细胞毒性有选择地靶向肿瘤。 我们将使用已证明（以其非工程状态）的梭菌孢子念珠菌（C. sporogenes）在人类患者中具有良好的耐受性，以及一种新的抗癌药物Pr-104，该药物最近进入了临床测试，并且在e. coli nitroreductase（Ntr）enzeme enzeme enzeme enzeme（spror contor contor contor contor contor）中对细胞有力毒性。 我们已经证明了在啮齿动物肿瘤模型中表达NTR与PR-104的孢子念珠菌组合的功效。 我们在此STTR中的总体目标是将SGM Biotech的专业知识相结合，该SGM Biotech在GMP条件下在GMP条件下生产了C. sporogenes孢子，并与Stanford University的Brown Laboratory与Stanford University的Brown Laboratory进行了基因为CDEPT策略进行了基因设计的C.孢子虫，以开发有机体以进行最终的临床测试。 我们有三个特定的目的来实现这一目标：1）将裂梭菌的大肠杆菌NTR基因整合到孢子念珠菌的基因组（斯坦福大学）。 2）用足够数量的综合大肠杆菌基因生产重组孢子虫，以在斯坦福大学（SGM Biotech）进行最初的安全性和功效研究，3）测试GMP的表达和功效（Pr-104）与GMP产生了重组C. sporegenes C. sporegenes与Tumor bearor beator bearor beator beator beator beator beator beator beator beator beator beator beator beator bearor beator beator beator beator bearing bearing c. beator bearing小鼠（斯坦福大学）。 如果成功的话，该项目将能够临床测试对患者的细胞毒性化学治疗剂的特异性递送，从而增强抗肿瘤活性并最大程度地减少正常的组织毒性。 公共卫生相关性：该STTR提案提出了一种独特的策略，用于针对实体瘤的特定化学治疗剂的有效杀死浓度。 我们提出的方法可以防止整个动物的间接毒性作用，但允许在肿瘤中专门实现该药物的浓度，因为我们仅在肿瘤中直接激活该药物。