The role of IL-17 signaling in alcohol-induced HCC

摘要： 肝细胞癌是由肝炎病毒、非酒精性脂肪性肝炎、 以及酒精性肝病(ALD)，通常从肝纤维化发展到肝硬变和癌症。我们的 初步数据显示，脂肪变性肝细胞中IL-17信号的基因缺失显著 减轻ALD损伤小鼠肝细胞癌的发展，提示IL-17信号转导是抗肝癌的靶点 肝细胞癌治疗。我们的中心假设是IL-17信号调节趋化因子的产生，从头开始 脂肪变性肝细胞的脂肪生成和TNFRI的表达/更新。IL-17信号促进ALD-和 NASH通过激活肿瘤坏死因子/TnFRI-SREBP1/2-HcR7-胆固醇的合成和抑制而诱导肝癌 ARTS-1/NUC2依赖的TNFRI胞吐作用。这项研究的目的是通过以下方式来描述这种机制 其中IL-17A/IL-17RA信号调节代谢损伤肝细胞的反应，并比较 ALD和NASH模型中IL-17信号转导途径的研究策略：应对IL-17 ALD和NASH损伤的WT和肝细胞特异性IL-17RA的信号将同时进行比较 肝细胞癌基因敲除小鼠。我们确定在NASH和ALD损伤中IL-17信号是否被类似地激活 肝细胞。我们确定阻断脂肪变性肝细胞中的IL-17信号是否足以抑制肝癌 新陈代谢受损的肝脏中。尤其是IL-17在DEN-OR(MUP-uPA)发病机制中的作用。 将在WT和肝细胞特异性IL-17RA基因敲除小鼠中研究ALD和NASH损伤诱导的肝癌 (IL-17RAΔ-HEP小鼠)。肝细胞癌、炎症、脂肪变性和肝纤维化的发展将跨越所有人群 老鼠。WT和IL-17RA缺陷型AFP+YAP+肝细胞癌的诱变及脂肪变性肝细胞对 将对IL-17A进行表征。具体地说，我们确定趋化因子分泌、胆固醇合成是否 在代谢受损的IL-17RA缺陷肝细胞(AIM1)中被抑制。我们将通过以下方式测试一个新的假设 哪种IL-17信号促进TNF/TNFRI-Caspase2-SP1-SREBP1/2-DHCR7-dependent胆固醇 通过阻断ARTS-1-NUCB2调节的TNFRI胞吐(可能还有IL-2)合成脂肪变性肝细胞 6，IL-1RII)，从而延长肿瘤坏死因子(IL-6，IL-1)信号转导通路，促进酒精性肝细胞癌的发生。我们的 这些发现将通过对存档的IL-17RA-TNFRI信号通路的表征而被翻译到人类身上 肝细胞癌合并酒精性肝病患者的人肝。我们将测试是否对关键的IL-17信号进行治疗阻断 利用N-乙酰半乳糖胺在肝细胞中特异性表达的分子(IL-17RA、TNFRI、ARTS-1和DHCR7) (GalNAc)偶联反义RNA寡核苷酸(ASO)可有效抑制脂肪变性、纤维化和 NASH和ALD(AIM3)WT小鼠的肝癌模型。如果证实，肝细胞特异性阻断IL-17信号转导使用 GalNAc-ASOS可为ALD和NASH患者的肝细胞癌治疗提供新的策略。

ABSTRACT: Hepatocellular carcinoma (HCC) is caused by hepatitis virus HBV/HCV, non-alcoholic steatohepatitis (NASH), and alcoholic liver disease (ALD), which typically progress from liver fibrosis, to cirrhosis and cancer. Our preliminary data demonstrate that genetic deletion of IL-17 signaling in steatotic hepatocytes significantly attenuates the development of HCC in ALD-injured mice, suggesting that IL-17 signaling is a target for anti- HCC therapy. Our central hypothesis is that IL-17 signaling regulates chemokine production, de novo lipogenesis, and TNFRI expression/turnover in steatotic hepatocytes. IL-17 signaling promotes ALD- and NASH-induced HCC via activation of TNF/TNFRI-SREBP1/2-DHCR7-cholesterol synthesis, and suppression of ARTS-1/NUC2-dependent TNFRI exocytosis. The goal of the study is to characterize the mechanism by which IL-17A/IL-17RA signaling regulates responses in metabolically injured hepatocytes, and to compare the pathways of IL-17 signaling in the experimental models of ALD- and NASH. Strategy: Responses to IL-17 signaling will be compared side-by side in ALD- and NASH-injured WT and hepatocyte-specific IL-17RA knockout mice with HCC. We determine if IL-17 signaling is similarly activated in NASH- and ALD-injured hepatocytes. We determine if blocking of IL-17 signaling in steatotic hepatocytes is sufficient to suppress HCC in the metabolically injured liver. Specifically, the role of IL-17 in the pathogenesis of DEN- or (Mup-uPA)- induced HCC in ALD- and NASH-injury will be studied in WT and hepatocyte-specific IL-17RA knockout mice (IL-17RAΔHep mice). Development of HCC, inflammation, steatosis and liver fibrosis will be across all groups of mice. Mutagenesis of WT and IL-17RA-deficient AFP+YAP+ HCC, and responses of steatotic hepatocytes to IL-17A will be characterized. Specifically, we determine if chemokine secretion, cholesterol synthesis are suppressed in metabolically injured IL-17RA-deficient hepatocytes (AIM1). We will test a novel hypothesis by which IL-17 signaling facilitates TNF/TNFRI-Caspase2-SP1-SREBP1/2-DHCR7-dependent cholesterol synthesis in steatotic hepatocytes via blocking ARTS-1-NUCB2-regulated TNFRI exocytosis (and possibly IL- 6, IL-1RII) thereby prolonging TNF (IL-6, IL-1) signaling and promoting alcohol-induced HCC (AIM2). Our findings will be translated into humans by characterization of IL-17RA-TNFRI-signaling pathways in archived human livers from HCC patients with ALD. We will test if therapeutic blocking of the key IL-17 signaling molecules (IL-17RA, TNFRI, ARTS-1, and DHCR7) specifically in hepatocytes using N-acetylgalactosamine (GalNAc)-conjugated antisense RNA oligonucleotides (ASOs) can effectively suppress steatosis, fibrosis, and HCC in WT mice with NASH and ALD (AIM3). If proven, hepatocyte-specific blocking of IL-17 signaling using GalNAc-ASOs can provide a new strategy for HCC treatment in ALD and NASH patients.