Engineered self-destructing Salmonella as a colorectal cancer cure

工程化的自毁性沙门氏菌作为结直肠癌的治疗方法

• 批准号: 8079475
• 负责人: Wei Kong
• 金额: $ 19.3万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2013-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8079475
• 关键词: Anaerobic Bacteria; Angiogenic Proteins; Apoptosis; Area; Aspartate; Attenuated; Bacteria; Biological Response Modifier Therapy; Cancer Etiology; Cell Death; Cells; Cessation of life; Chemoreceptors; Chemotherapy-Oncologic Procedure; Colorectal Cancer; Cytolysis; DNA Vaccines; Development; Diagnosis; Diffusion; Drug resistance; Engineering; Enzymes; Exhibits; Genes; Genetic; Human; Hypoxia; Immune; Immune response; Immune system; Implant; Individual; Lead; Legal patent; Malignant Neoplasms; Malignant neoplasm of lung; Micrometastasis; Morbidity - disease rate; Mus; Normal tissue morphology; Oncogenes; Organ; Outcome; Phenotype; Prodrugs; Protein Biosynthesis; Proteins; Protocols documentation; Radiation therapy; Recombinants; Resistance; Salmonella; Salmonella enterica; Salmonella typhimurium; Serine; Site; Solid Neoplasm; Survival Rate; System; Targeted Toxins; Technology; Therapeutic; Time; Tissues; Toxic effect; Tumor Necrosis Factor Ligand Superfamily Member 6; Tumor Tissue; United States; Virulence Factors; base; cancer cell; cancer radiation therapy; cancer therapy; chemotherapy; conventional therapy; cytotoxic; design; design and construction; gene therapy; improved; killings; mortality; neoplastic cell; novel; novel strategies; programs; promoter; public health relevance; research study; tumor; tumor eradication; tumor growth; vector

DESCRIPTION (provided by applicant): We have constructed the attenuated hyper-invasive Salmonella enterica serovar Typhimurium (hereinafter S. Typhimurium), that are attenuated, yet capable of synthesizing selected protein and harboring an improved DNA vaccine vector encoding a selected protein. The programmed self-destructing features designed into these S. Typhimurium strains allow release of the cell contents by cell lysis after bacteria accumulated in host tissues. This proposal was promoted by the idea that if the selected proteins are able to trigger tumor cell apoptosis, then the engineered self-destructing Salmonella could serve as a programmed "bio-time-bomb" to destroy tumor tissues by release of tumor killing materials after colonization in tumor tissues. Colorectal cancer is the second leading cause of cancer-related deaths in the United States (after lung cancer). A major challenge in treating cancer is the difficulty of bringing therapy to poorly perfused areas of solid tumors, which are often most resistant to chemo- and radiotherapy. Motile facultative S. Typhimurium strains, which are specifically attracted to compounds produced by quiescent cancer cells and could overcome the traditional therapeutic barrier. It is known that attenuated S. Typhimurium preferably target and penetrate into tumor tissue allowing to accumulate about 2,000-fold more in tumors than in other organs, where they could overcome diffusion limitations and attack quiescent cancer cells that are impervious to standard chemo- and radiotherapy. Therefore we wish to explore the potential to use the engineered self-destructing Salmonella as a colorectal cancer cure. Our objective is to design, construct and evaluate a novel inexpensive rapidly modifiable recombinant attenuated S. Typhimurium (RAS) delivery system that will be a "time bomb" with multiple functional biotherapy agents as an optimal colorectal cancer cure to overcome chemo- and radiotherapeutic resistance. The (RAS) delivery system with newly developed features will (i) be hyper- invasive, (ii) selectively synthesize bacterial serine and aspartate chemoreceptors to facilitate maximal colonization of tumor tissues, (iii) displays regulated delayed synthesis of S. Typhimurium T3SS effector SopE2 that stimulates innate immune responses, and (iv) exhibits regulated delayed lysis to efficiently deliver the bacterial virulence factor TlpA, that directed by Salmonella promoter preferentially activated inside tumors, to induce apoptosis in tumor cells, and an improved DNA vaccine vector encoding a tumor-specifically synthesized death ligand Fas to trigger tumor cell death and also to attract immune cells to attack tumor cells. This RAS delivery system will have features to render it completely safe for humans administered the engineered Salmonella and to be unable to persist in immunized individuals or survive if excreted. Furthermore, we believe that the designing, constructing and evaluating an engineered Salmonella-based cancer cure would represent a highly effective means to reduce systemic toxicity of cancer treatment and perhaps lead to eradication of tumors from the host. ) PUBLIC HEALTH RELEVANCE: The engineered self-destructing Salmonella could serve as a programmed "bio-time-bomb" to destroy tumor tissues by release of tumor killing materials after colonization in tumor tissues. The designing, constructing and evaluating an engineered Salmonella-based colorectal cancer cure would represent a highly effective means to overcome chemo- and radiotherapeutic resistance, to reduce systemic toxicity of cancer treatment and perhaps lead to eradication of tumors from the host.

描述（由申请人提供）：我们构建了减毒的超侵袭性肠道沙门氏菌血清型鼠伤寒沙门氏菌（下文称为S.鼠伤寒沙门氏菌），其是减毒的，但能够合成选定的蛋白质并携带编码选定蛋白质的改进的DNA疫苗载体。设计在这些S.鼠伤寒杆菌菌株允许在宿主组织中积累细菌后通过细胞裂解释放细胞内容物。这一提议是由这样的想法推动的，即如果所选择的蛋白质能够触发肿瘤细胞凋亡，那么工程化的自毁沙门氏菌可以作为程序化的“生物定时炸弹”，通过在肿瘤组织中定植后释放肿瘤杀伤物质来摧毁肿瘤组织。结直肠癌是美国癌症相关死亡的第二大原因（仅次于肺癌）。治疗癌症的一个主要挑战是难以将治疗带到实体瘤的灌注不良区域，这些区域通常对化疗和放疗最具抵抗力。能动兼性S.鼠伤寒杆菌菌株，它们特异性地被静止癌细胞产生的化合物所吸引，可以克服传统的治疗障碍。众所周知，减毒S.鼠伤寒沙门氏菌优选靶向并渗透到肿瘤组织中，使其在肿瘤中的积累比在其他器官中多约2，000倍，在那里它们可以克服扩散限制并攻击对标准化疗和放疗不敏感的静止癌细胞。因此，我们希望探索使用工程自毁沙门氏菌作为结直肠癌治疗的潜力。我们的目的是设计、构建和评价一种新型廉价的、可快速修饰的重组减毒沙门氏菌。鼠伤寒沙门氏菌（RAS）输送系统，这将是一个“定时炸弹”与多功能生物治疗剂作为一个最佳的结肠直肠癌治疗，以克服化疗和放疗的阻力。具有新开发特征的（RAS）递送系统将（i）是超侵入性的，（ii）选择性合成细菌丝氨酸和天冬氨酸化学受体以促进肿瘤组织的最大定殖，（iii）显示S.鼠伤寒T3SS效应子SopE2，其刺激先天性免疫应答，和（iv）表现出调节的延迟裂解以有效递送细菌毒力因子TlpA，其由在肿瘤内优先活化的沙门氏菌启动子指导，以诱导肿瘤细胞的凋亡，和编码肿瘤的改进的DNA疫苗载体，特异性合成死亡配体Fas以触发肿瘤细胞死亡并且还吸引免疫细胞攻击肿瘤细胞。这种RAS递送系统将具有使其对施用工程化沙门氏菌的人完全安全的特征，并且如果排泄，则不能在免疫个体中持续存在或存活。此外，我们相信，设计、构建和评估工程化的基于沙门氏菌的癌症治疗将代表一种高度有效的手段，以减少癌症治疗的全身毒性，并可能导致从宿主中根除肿瘤。) 公共卫生关系：这种工程化的自毁沙门氏菌可以作为一个程序化的“生物定时炸弹”，通过在肿瘤组织中定植后释放肿瘤杀伤物质来摧毁肿瘤组织。设计、构建和评估工程化的基于沙门氏菌的结直肠癌治疗将代表克服化疗和放疗抗性、降低癌症治疗的全身毒性并可能导致从宿主中根除肿瘤的高度有效的手段。