Gasdermin E-mediated pyroptosis in promoting antitumor immunity and cancer treatment

项目摘要/摘要 大多数癌症是免疫“冷”的，T细胞浸润有限，表现出极差的反应。 接受免疫治疗的比率。增强肿瘤浸润性淋巴细胞募集和功能的新策略 (TIL)是改善癌症免疫治疗的迫切需要。癌细胞如何在压力下死亡， 细胞毒性淋巴细胞，而药物对癌症的免疫格局有着深远的影响。虽然大多数癌症 细胞死亡被认为是非炎症性的，我们最近的研究表明，孔形成蛋白Gasdermin E(GSDME)，当在肿瘤细胞中表达时，将非炎性细胞凋亡转化为上睑下垂，这是一种高度 炎症形式的程序性细胞死亡。GSDME有效抑制肿瘤生长并增加肿瘤数量 CD8+和NK细胞的抗肿瘤作用。GSDME的抑瘤作用是通过TIL杀伤作用实现的 GSDME+靶肿瘤细胞，也可引发肿瘤细胞下垂。我们的研究表明，促进 癌细胞下垂具有极好的改善癌症免疫治疗的潜力，但如何改善仍不清楚。 GSDME诱导的下垂增强抗肿瘤免疫。这项拟议的研究旨在调查肿瘤是如何 GSDME的表达塑造了肿瘤浸润性免疫细胞及其相互作用，从而提高了肿瘤免疫力。 并开发一种新的策略来促进炎性癌细胞死亡，长期目标是增强 对癌症患者的免疫治疗效果。具体地说，我将研究损伤相关的分子 GSDME+肿瘤细胞产生的模式(DAMP)调节细胞的组成、成熟和功能 肿瘤浸润性树突状细胞(TIDCs)和肿瘤相关巨噬细胞(TAM)，诱导 有效的抗肿瘤T细胞反应，通过使用细胞因子和DAMP或其受体的抑制剂(目标1)。协助者 单细胞(Sc)rna-seq和骨髓嵌合小鼠，我将研究不同的tidc亚群如何与 CD8+TIL促进GSDME介导的抗肿瘤免疫(目标2)。许多癌细胞在表观遗传学上保持沉默 GSDME和RIPK3(细胞死亡的另一种炎性形式--坏死性下垂的关键介质)通过启动子 高甲基化，我将研究DNA甲基化抑制剂地西他滨是否可以促进癌细胞 抑制肿瘤生长和增强抗肿瘤免疫力的上睑下垂和坏死下垂(目标3)。这些研究 将极大地促进我们对GSDME免疫刺激机制的了解，并提供新的机会 目的：恢复未发炎的感冒肿瘤患者的免疫治疗效果。我的职业目标是领导 一个独立的学术实验室，研究癌症免疫学和免疫疗法方面的问题。在 K99阶段，我将充分利用哈佛充满活力的研究社区的广泛资源 以及优秀的导师和合作者团队，接受高级 技术、生物信息学、老鼠模型和翻译研究，以进一步建立合作和 磨练我的专业技能。拟议的培训计划将成为一个极好的路线图，将引导我 我的目标是作为一名独立的调查者取得成功，并改变癌症患者的生活。

Project Summary/Abstract The majority of cancers, which are immunologically “cold” with limited T cell infiltration, show abysmal response rates to immunotherapy. Novel strategies to enhance recruitment and functions of tumor-infiltrating lymphocytes (TIL) are urgently needed to improve cancer immunotherapy. How cancer cells die in response to stress, cytotoxic lymphocytes, and drugs has a profound impact on the immune landscape of cancer. While most cancer cell death has been viewed as noninflammatory, our recent study showed that pore-forming protein Gasdermin E (GSDME), when expressed in tumor cells, converts noninflammatory apoptosis to pyroptosis, a highly inflammatory form of programmed cell death. GSDME potently inhibits tumor growth and enhances the numbers and antitumor functions of CD8+ and NK TILs. The tumor-inhibitory effect of GSDME is mediated by TIL killing of GSDME+ target tumor cells, which can also trigger tumor cell pyroptosis. Our study suggests that promoting cancer cell pyroptosis has excellent potential to improve cancer immunotherapy, but it remains unclear how GSDME-induced pyroptosis boosts antitumor immunity. The proposed research aims to investigate how tumor GSDME expression shapes the tumor-infiltrating immune cells and their interactions to increase tumor immunity, and to develop a novel strategy to promote inflammatory cancer cell death, with the long-term goal to enhance immunotherapeutic efficacy for cancer patients. Specifically, I will study how damage-associated molecular patterns (DAMPs) produced by GSDME+ tumor cells modulate the composition, maturation, and functions of tumor-infiltrating dendritic cells (TIDCs) and tumor-associated macrophages (TAMs), key players to induce potent antitumor T cell response, by using CyTOF and inhibitors of DAMPs or their receptors (Aim 1). Aided by single cell (sc)RNA-seq and bone marrow chimeric mice, I will study how different TIDC subsets interact with CD8+ TILs to promote GSDME-mediated antitumor immunity (Aim 2). As many cancer cells epigenetically silence GSDME and RIPK3 (key mediator of necroptosis, another inflammatory form of cell death) via promoter hypermethylation, I will investigate whether the DNA methylation inhibitor decitabine could promote cancer cell pyroptosis and necroptosis to suppress tumor growth and enhance antitumor immunity (Aim 3). These studies will greatly advance our understanding of GSDME’s immunostimulatory mechanism and offer new opportunities to revitalizing immunotherapeutic efficacy for patients with uninflamed “cold” tumors. My career goal is to lead an independent academic laboratory addressing questions on cancer immunology and immunotherapy. In the K99 phase, I will take full advantage of the extensive resources at the vibrant research community of Harvard and the outstanding team of mentors and collaborators to receive comprehensive training in advanced technologies, bioinformatics, mouse models, and translational research, to further establish collaborations and sharpen my professional skills. The proposed training plan will serve as a superb roadmap that will lead me to my goal of succeeding as an independent investigator, and to make a difference in the lives of cancer patients.