Hypoxia-activated probiotic agents for breast cancer

摘要 缺氧是包括乳腺癌在内的实体瘤的主要特征之一，已被证明 与预后不佳有关。尽管许多化疗药物，如紫杉醇和 阿霉素在常氧环境下显著有效，对缺氧性肿瘤效果较差 由于输液不足、缺氧和酸度过高而导致的区域。鉴于其对治疗和肿瘤的重大影响 进展，一种特异性靶向肿瘤缺氧区的新方法的开发 临床上需要的。为了应对挑战(未得到满足的医疗需求)，我们这项提案的目标是 开发一种新的益生菌辅助方法，因为细菌优先在低氧环境中迁移和积累 肿瘤的区域。我们开发了我们独创的缺氧诱导表达系统，并对其进行了优化 用于已被用作人类益生菌的大肠杆菌G3/10细胞。我们证明了G3/10 细胞优先定位异种移植的小鼠乳腺肿瘤的缺氧区。使用新的工具 在G3/10细胞的低氧诱导表达系统中，我们将运送杀癌的铜氧还蛋白， 三阴性乳腺癌缺氧区的天青素或黄花青素，因为它们的治疗有限 选择和更糟糕的预后。我们假设一种新的细菌辅助方法的发展 在低氧诱导启动子下表达肿瘤杀伤蛋白将为以下方面提供功能工具 专门针对缺氧性肿瘤。为了检验我们的假设并改进目前的治疗方法，我们设计了 基于我们的“双向”策略的实验；基于G3/10的治疗与标准治疗相结合 化疗药物(紫杉醇和阿霉素)，以使化疗抑制肿瘤 外周区域，灌流的肿瘤区域，我们的细菌方法在缺氧的内部杀死肿瘤 地区。我们的初步数据有力地支持了这一概念。考虑到NIH/NCI的重点领域是 FOA PAR-22-085(基于微生物的癌症成像和治疗-虫子作为药物)，我们专门形成了一个 整合基础、翻译和临床乳腺癌生物学专业知识的多学科团队， 微生物学、分子生物学、免疫学、病理学和生物统计学。在五年的临床前工作中 在这项应用中提出的研究，我们将发现工程G3/10细胞的价值是有效的 细菌辅助的功能工具。拟议研究的结果可能会提供新的和 针对缺氧肿瘤微环境的有效治疗策略。

ABSTRACT Hypoxia is one of the main features of solid tumors including breast cancer and has been shown to correlate with a poor prognosis. Although many chemotherapeutic agents such as paclitaxel and doxorubicin are significantly effective in a normoxia environment, they are less effective in hypoxic tumor regions due to poor infusion, hypoxia, and acidity. Given its significant impact on treatment and tumor progression, the development of a new approach to specifically target the hypoxic regions of tumors is clinically needed. To address the challenges (unmet medical needs), our objective for this proposal is to develop a new probiotic-assisted approach as bacteria preferentially migrate and accumulate in the hypoxic region of the tumor. We developed our original hypoxia-inducible expression system and have optimized its use in E. coli G3/10 cells, which have been used as a probiotic in humans. We demonstrated that the G3/10 cells preferentially localized the hypoxic regions of xenografted breast tumors in mice. With the new tools of the hypoxia-inducible expression system in G3/10 cells, we will deliver cancer-killing cupredoxin proteins, azurin or rusticyanin, in the hypoxic region of triple-negative breast cancer as they have limited treatment options and a worse prognosis. We hypothesize that the development of a new bacteria-assisted approach to express cancer-killing proteins under the hypoxia-inducible promoter will provide functional tools for specifically targeting hypoxic tumors. To test our hypothesis and improve current therapy, we designed experiments based on our “bi-directional” strategy; a combination of the G3/10-based therapy with standard chemotherapeutic agents (paclitaxel and doxorubicin), so that the chemotherapy suppresses tumors in the outer periphery regions, perfused tumor regions, and our bacterial approach kills tumor in the hypoxic inner regions. Our preliminary data strongly support this concept. Considering the NIH/NCI’s focusing areas in FOA PAR-22-085 (Microbial-based Cancer Imaging and Therapy - Bugs as Drugs), we specifically formed a multidisciplinary team that integrates expertise in basic, translational, and clinical breast cancer biology, microbiology, molecular biology, immunology, pathology, and biostatistics. With the five years of preclinical research proposed in this application, we will discern the value of engineered G3/10 cells as effective bacteria-assisted functional tools. Results from the proposed studies will potentially provide new and effective treatment strategies that specifically target the hypoxic tumor microenvironment.