Pseudo-hypoxic contributions to the tumor microenvironment in kidney cancer

摘要 透明细胞肾细胞癌（ccRCC）是最常见的肾癌类型，其特征在于失调的肾细胞癌（CCCC）。 缺氧信号传导、代谢缺陷和肿瘤微环境（TME）中的复杂免疫细胞浸润。 氧敏感基因von Hippel Lindau（VHL）的缺失是ccRCC发病机制中的关键早期事件， 促进缺氧诱导（转录）因子（HIF）的稳定，HIF上调促生长信号传导 途径，包括有氧糖酵解，无论氧气的可用性。这种现象被称为“伪- 缺氧。”影响ccRCC的最常见的免疫类型是功能受损的CD 8肿瘤浸润， 淋巴细胞（CD 8 TIL）和代谢增强的肿瘤相关巨噬细胞（TAM）。的进步 免疫肿瘤学通过免疫检查点阻断（ICB）改善了患者的总体结局 然而，目前的治疗方式并不能使大多数ccRCC患者产生持久的反应。我 提出与假性缺氧信号相关的特征促进癌细胞能量的改变， 影响TME中免疫细胞功能的要求，揭示这些方面可能会提供新的 治疗的机会。我的初步数据表明Vhl缺失有利于成熟的TAM髓样表型 在小鼠肾细胞癌中线粒体代谢增强，这一结果与代谢增强一致 在人ccRCC的髓样区室中观察到。此外，TAM对CD 8 TIL的抑制可能是 通过与癌细胞的特异性相互作用增强，尽管确切的TAM功能尚不清楚。在这 建议，我将测试的假设，假缺氧信号从癌细胞在TME 优先支持促进CD 8 TIL抑制的代谢活性TAM亚群， 抑制TAM活性将增强CD 8 TIL对ICB治疗的反应。为了检测癌细胞的伪- 缺氧对TAM功能影响我已经开发了一种基于细针抽吸的患者来源的类器官（FNA， PDO）模型，该模型概括了人类肿瘤中TME的关键因素。我还会雇一对老鼠 同源Renca细胞系模型（Vhl WT和Vhl KO），以解决假缺氧对TME的影响， vivo.我将：（1）测试假性缺氧是否支持具有不同代谢的独特TAM表型;以及（2）测试 TAM在T细胞抑制和ICB反应中的作用。最终，这些研究将推动我们目前的 通过展示塑造TME的机制和突出新的肾癌生物学知识， 改善免疫疗法的策略。

ABSTRACT Clear cell renal cell carcinoma (ccRCC), the most common type of kidney cancer, is characterized by deregulated hypoxic signaling, metabolic defects, and complex immune cell infiltrate in the tumor microenvironment (TME). Loss of the oxygen sensing gene, von Hippel Lindau (VHL), is a critical early event in ccRCC pathogenesis and promotes stabilization of hypoxia inducible (transcription) factors (HIF) that upregulate pro-growth signaling pathways, including aerobic glycolysis, regardless of oxygen availability. This phenomenon is termed “pseudo- hypoxia.” The most frequent immune types affecting ccRCC are functionally impaired CD8 tumor infiltrating lymphocytes (CD8 TIL) and metabolically enhanced tumor associated macrophages (TAM). Advancements in immune oncology have led to improved overall patient outcomes with immune checkpoint blockade (ICB) therapy; however, current modalities do not result in durable responses for the majority of ccRCC patients. I propose that features linked to pseudo-hypoxic signaling promote alterations in cancer cell energetic requirements that impact immune cell function in the TME and revealing these aspects may provide new opportunities for therapy. My preliminary data indicate that Vhl loss favors a mature TAM myeloid phenotype with enhanced mitochondrial metabolism in murine RCC, and this result is consistent with enhanced metabolism observed in the myeloid compartment of human ccRCC. Additionally, TAM suppression of CD8 TIL may be enhanced by specific interactions with cancer cells, though exact TAM functions are not understood. In this proposal, I will test the hypothesis that pseudo-hypoxic signals from cancer cells in the TME preferentially support a metabolically active TAM subset that promotes CD8 TIL suppression and that inhibiting TAM activity will enhance the CD8 TIL response to ICB therapy. To test the cancer cell pseudo- hypoxic effect on TAM function I have developed a fine needle aspiration-based patient-derived organoid (FNA- PDO) model that recapitulates key factors of the TME in human tumors. I will also employ a pair of murine syngeneic Renca cell line models (Vhl WT and Vhl KO) to address the impact of pseudo-hypoxia on the TME in vivo. I will: (1) Test if pseudo-hypoxia supports a unique TAM phenotype with distinct metabolism; and (2), Test the role of TAM in T cell suppression and ICB response. Ultimately, these studies will advance our current understanding of kidney cancer biology by demonstrating mechanisms that shape the TME and highlighting new strategies to improve immunotherapy.