Project 4: Interrogating and harnessing age-related IFN signaling and innate immunity in HCC prevention and therapy

项目概要-项目4 原发性肝癌，主要是肝细胞癌（HCC），是目前最致命的恶性肿瘤之一。 衰老是HCC发展的高风险因素，尽管其潜在机制尚不清楚。 衰老的肝脏的特征在于免疫抑制微环境的进行性发展， 慢性干扰素（IFN）信号，代谢变化和改变先天性和适应性免疫。 因此，肝脏肿瘤对免疫疗法的反应很差。项目4的目标是阐明干扰素的作用 和其他炎性细胞因子在肝脏免疫景观的衰老相关变化。这个项目 是由我们在最近实验中的意外发现引发的。在剖析 肝肿瘤发生与诱导基因靶向系统，Mx 1-cre，我们确定了一个强大的肿瘤抑制 多聚肌苷酸-多聚胞苷酸（polyIC），一种诱导IFN表达的合成dsRNA的作用。这些数据对 IFN信号不仅挑战了肝肿瘤发生中IL 1a-IL 6细胞因子回路的广泛已知理论， 也为HCC免疫治疗开辟了新的策略。然而，初步数据也显示， 多聚IC进入老年小鼠引发了截然不同的免疫反应，实际上加剧了HCC的进展 如果在晚期肿瘤阶段给予。因此，我们假设干扰素和其他相关的炎症细胞因子， 在HCC发展中的双向或矛盾作用，取决于年龄和肿瘤分期。为了验证这一 假设，我们将广泛询问IFN信号转导在NASH-HCC模型中的作用，在单细胞 分辨率我们还将进一步发展和优化数学模型和TI（肿瘤发生指数）计算 系统定量测量致瘤信号强度、肿瘤分期和预后， 各种操作或治疗策略的肿瘤抑制作用。值得注意的是，初步数据还显示， 肝脏中polyIC对PD-L1表达的稳健诱导，这促使我们测试polyIC与 和PD-L1/PD-1阻断剂治疗年轻和老年小鼠肝癌。我们将深入调查 先天性和适应性免疫功能的协调激活如何有效地抑制原发性和 肝脏转移性肿瘤进展。最后，我们将利用新建立的小鼠肿瘤 模型，系统地寻找肝脏特异性因素和免疫治疗抵抗机制。所有 在这个雄心勃勃的项目中，只有与沙德尔、亚当斯和 Kaech与互补的专业知识和核心。

PROJECT SUMMARY – PROJECT 4 Primary liver cancer, mainly hepatocellular carcinoma (HCC), is now one of the most deadly malignant diseases. Aging is a high-risk factor for HCC development, although the underlying mechanisms are poorly understood. The aging liver is characterized by progressive development of an immunosuppressive microenvironment, contributed by chronic interferon (IFN) signaling, metabolic changes and altered innate and adaptive immunity. Thus, liver tumors are poorly responsive to immunotherapy. The goal of project 4 is to elucidate the roles of IFN and other inflammatory cytokines in aging-related changes of the hepatic immunological landscape. This project was prompted by our unexpected finding in most recent experiments. In dissecting molecular mechanisms of liver tumorigenesis with an inducible gene targeting system, Mx1-cre, we identified a robust tumor-inhibitory effect of polyinosinic-polycytidylic acid (polyIC), a synthetic dsRNA that induces IFN expression. These data on IFN signaling not only challenge a widely known theory of IL1a-IL6 cytokine circuit in liver tumorigenesis, but also open up new strategies for HCC immunotherapy. However, preliminary data also showed that injecting polyIC into aged mice triggered sharply different immune responses and actually aggravated HCC progression if given at late tumor stages. Thus, we hypothesize that IFN and other related inflammatory cytokines have bidirectional or paradoxical roles in HCC development, depending on ages and tumor stages. To test this hypothesis, we will extensively interrogate the roles of IFN signaling in a NASH-HCC model at single cell resolution. We will also further develop and optimize a math model and a TI (tumorigenic index) calculation system to quantitatively measure tumorigenic signal strength, tumor stages and prognosis, and also evaluate tumor-inhibitory effects of various manipulation or treatment strategies. Of note, preliminary data also showed robust induction of PD-L1 expression by polyIC in the liver, which prompted us to test a combination of polyIC and PD-L1/PD-1 blockade in treatment of liver cancer in young and old mice. We shall extensively investigate how coordinated activation of innate and adaptive immune functions can effectively suppress primary and metastatic tumor progression in the liver. Finally, we shall take advantage of newly established mouse tumor models, to systematically search for liver-specific factors and mechanisms of resistance to immunotherapy. All of the proposed experiments in this ambitious project can only be done in collaboration with Shadel, Adams and Kaech with complementary expertise and the Cores.