CAREER: Engineered tumor models to study the recruitment and activation of Natural Killer cells

尽管在药物发现和早期诊断方面取得了进展，但癌症仍然是全球第二大死亡原因。最近的突破显示，在一些难以治疗的癌症中取得了良好的临床结果，但应答率一直不同，许多治疗方法都会导致不想要的副作用。因此，人们对开发提高人体自身自然杀伤细胞(NK)能力的治疗方法产生了新的兴趣。NK细胞是一种免疫系统细胞，具有识别癌细胞并摧毁它们的能力。不幸的是，肿瘤创造了一种局部环境，称为肿瘤微环境，它抑制了NK细胞的功能，从而允许癌症不受控制地生长。该学院早期职业发展计划(Career)项目的目标是设计肿瘤微环境的三维模型，并询问影响NK细胞如何迁移到肿瘤和识别癌细胞的生化和机械线索。这些研究产生的知识可能为NK细胞提供新的治疗靶点或策略，以克服免疫抑制的肿瘤微环境，攻击癌细胞。该研究项目将为研究生和本科生提供肿瘤生物学、免疫学和组织工程学前沿领域的跨学科培训。该项目的教育目标是开发课程和外联活动，使K-12、本科生和研究生水平的学生兴奋地了解科学、技术、工程和数学(STEM)职业对当地社区和整个社会的影响。特别是，旨在提高人们对STEM教育提供的机会的认识的外联活动将针对佛罗里达州中北部服务不足和经济困难学校的中学生和教师。该项目的目标是开发工程化的肿瘤微环境，以询问影响自然杀伤(NK)细胞迁移和活性的生化和机械线索。与T细胞不同，NK细胞可以通过识别“应激信号”和新生肿瘤细胞表面配体的变化来发挥不依赖于抗原的功能，这些变化对应于激活NK细胞上的受体。NK细胞的过继细胞转移在根除某些血液系统恶性肿瘤方面显示出了希望；然而，实体恶性肿瘤被证明更具挑战性。为了在实体瘤中发挥其效应功能，NK细胞必须在肿瘤间质中迁移，并与癌细胞进行细胞间接触。虽然许多研究都集中在增强NK细胞-癌细胞突触的NK细胞活性上，但如果没有足够的NK细胞渗透，这些策略最终可能是无效的。该研究计划的第一个目标是设计一种可调的3D培养系统，以研究NK细胞与ECM的相互作用如何影响NK细胞的招募。各种基于聚乙二醇基的水凝胶将被设计成具有可调节的物理和生化特性，如硬度、细胞黏附位置、酶降解位置和肿瘤相关的蛋白多糖，以询问影响NK细胞募集的生化和机械信号。工作假设是，细胞外基质的组成和硬度将影响NK细胞的迁移和激活，以响应趋化梯度。NK细胞的迁移程度、迁移机制和细胞因子的产生将在工程微环境中进行评估。该研究计划的第二个目标是表征细胞外微环境如何影响NK细胞和癌细胞的相互作用。肿瘤免疫抑制机制和NK细胞-癌细胞的相互作用将在生理相关的3-D系统中进行研究。工作假设是ECM的组成和硬度影响肿瘤中的免疫抑制机制，从而影响NK细胞和癌细胞的相互作用。这些研究的结果将推动癌症免疫治疗领域的发展，并导致针对实体恶性肿瘤的NK细胞治疗的新策略以及用于评估其有效性的新的体外工具。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Despite advances in drug discovery and early diagnosis, cancer remains the second leading cause of death worldwide. Recent breakthroughs have demonstrated good clinical outcomes in a number of difficult-to-treat cancers, but response rates have been variable and many treatments result in unwanted side effects. Thus, there is an emerging interest in developing therapies that enhance the ability of the body's own Natural Killer (NK) cells, which are immune system cells that have the ability to recognize cancer cells and destroy them. Unfortunately, tumors create a local environment, called the tumor microenvironment, that suppresses the functions of the NK cells and thereby allows the cancer to grow unchecked. The goal of this Faculty Early Career Development Program (CAREER) project is to engineer three-dimensional models of the tumor microenvironment and to interrogate the biochemical and mechanical cues that impact how NK cells migrate into tumors and recognize cancer cells. The knowledge generated by these studies could lead to new therapeutic targets or strategies for NK cells to overcome the immunosuppressive tumor microenvironment and attack cancer cells. The research project will provide graduate and undergraduate students with interdisciplinary training at the cutting edge of tumor biology, immunology, and tissue engineering. The education goals of the project are to develop curricula and outreach activities that will excite students at the K-12, undergraduate, and graduate levels about the impact of science, technology, engineering, and math (STEM) professions on their local communities and society as a whole. In particular, outreach activities aimed at increasing awareness of the breath of opportunities that a STEM education provides will be targeted to middle school students and teachers in underserved and economically disadvantaged schools in north-central Florida. The goal of this project is to develop engineered tumor microenvironments to interrogate the biochemical and mechanical cues that impact Natural Killer (NK) cell migration and activity. Unlike T-cells, NK cells can function in an antigen independent manner by recognizing "stress signals" and alterations in cell surface ligands on nascent tumor cells that correspond to activating receptors on NK cells. Adoptive cell transfer of NK cells has demonstrated promise in eradicating certain hematological malignancies; however, solid malignancies have proved more challenging. To exert their effector functions in solid tumors, NK cells must migrate through the tumor stroma and make cell-to-cell contact with cancer cells. While much research is focused on enhancing NK cell activation at the NK cell-cancer cell synapse, without sufficient NK cell infiltration these strategies may ultimately be inefficient/ineffective. The first objective of the research plan is to engineer a tunable 3-D culture system to investigate how NK cell-ECM interactions impact NK cell recruitment. Various poly(ethylene glycol)-based hydrogels will be engineered with tunable physical and biochemical properties such as stiffness, cell adhesion sites, enzymatic degradation sites, and tumor-related proteoglycans to interrogate the biochemical and mechanical cues that impact NK cell recruitment. The working hypothesis is that ECM composition and stiffness will impact NK cell migration and activation in response to chemotactic gradients. The extent of NK cell migration, the mechanism of migration, and cytokine production will be assessed in the engineered microenvironments. The second objective of the research plan is to characterize how the extracellular microenvironment impacts NK cell-cancer cell interactions. Tumor immunosuppression mechanisms and NK cell-cancer cell interactions will be examined in physiologically relevant 3-D systems. The working hypothesis is that the composition and stiffness of the ECM influences the immunosuppressive mechanisms in tumors and, consequently, NK cell-cancer cell interactions. The results from these studies will advance the field of cancer immunotherapies and lead to new strategies for NK cell therapies in solid malignancies as well as new in vitro tools for evaluating their effectiveness.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.