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

摘要： 肝细胞癌（HCC）是由肝炎病毒HBV/HCV、非酒精性脂肪性肝炎（NASH） 和酒精性肝病（ALD），其通常从肝纤维化进展到肝硬化和癌症。我们 初步数据表明，脂肪变性肝细胞中IL-17信号传导的遗传缺失显著地 在ALD损伤的小鼠中减弱HCC的发展，表明IL-17信号传导是抗- HCC治疗。我们的中心假设是IL-17信号转导从头调节趋化因子的产生， 脂肪变性肝细胞中的脂肪生成和TNFRI表达/转换。IL-17信号传导促进ALD-和 通过激活TNF α/TNFRI-SREBP 1/2-DHCR7-胆固醇合成和抑制NASH诱导的HCC ARTS-1/NUC2依赖性TNFRI胞吐作用。该研究的目标是通过以下方式表征该机制： IL-17A/IL-17RA信号调节代谢损伤肝细胞的反应，并比较 在ALD和NASH实验模型中的IL-17信号通路。策略：对IL-17的反应 将在ALD和NASH损伤的WT和肝细胞特异性IL-17 RA中并排比较信号传导 基因敲除的HCC小鼠。我们确定IL-17信号在NASH和ALD损伤的 肝细胞我们确定在脂肪变性肝细胞中阻断IL-17信号传导是否足以抑制HCC 代谢受损的肝脏具体而言，IL-17在DEN-或（Mup-uPA）-的发病机制中的作用是， 将在WT和肝细胞特异性IL-17RA敲除小鼠中研究ALD和NASH损伤中诱导的HCC （IL-17RA Δ Hep小鼠）。HCC、炎症、脂肪变性和肝纤维化的发展将在所有治疗组中进行。 小鼠WT和IL-17 RA缺陷型AFP+雅普+HCC的突变，以及脂肪变性肝细胞对 将表征IL-17A。具体来说，我们确定趋化因子分泌，胆固醇合成是否 在代谢损伤的IL-17RA缺陷型肝细胞（AIM 1）中受到抑制。我们将测试一个新的假设， IL-17信号促进TNF α/TNFRI-Caspase2-SP1-SREBP 1/2-DHCR7依赖性胆固醇 通过阻断ARTS-1-NUCB 2调节的TNFRI胞吐（以及可能的IL-10）在脂肪变性肝细胞中的合成 6 β，IL-1 β RII），从而延长TNF β（IL-6，IL-1 β）信号传导并促进酒精诱导的HCC（AIM 2）。我们 研究结果将通过表征IL-17RA-TNFRI-信号通路转化为人类， 来自患有ALD的HCC患者的人类肝脏。我们将测试治疗性阻断关键的IL-17信号传导是否 使用N-乙酰半乳糖胺在肝细胞中特异性检测IL-17 RA、TNFRI、ARTS-1和DHCR7分子 （GalNAc）缀合的反义RNA寡核苷酸（ASO）可以有效地抑制脂肪变性、纤维化和肝纤维化。 患有NASH和ALD的WT小鼠中的HCC（AIM 3）。如果得到证实，肝细胞特异性阻断IL-17信号传导， GalNAc-ASO可以为ALD和NASH患者的HCC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.