High fat diet induced hepatocyte exosomes-promoted hepatic inflammation and tumorigenesis

摘要 这项建议的总体目标是研究肝细胞外切体在高脂饮食中的作用。 促进肝癌的发展。此外，我们将确定是否使用新的可食用水果外切体 作为靶向向肿瘤细胞递送抗炎剂的载体用于肝脏治疗 癌症。我们的初步数据表明，猪外周血中存在肝细胞外切体。 肥胖小鼠和肥胖个体以及喂食高脂饮食(HFD-1)的小鼠的肝细胞外体 Exosome)促进小鼠模型的炎症反应和肝癌生长。这些数据 肝细胞外切体的产生与肝癌相关的炎症反应有关。 我们的初步数据表明，HFD-exosome携带高水平的相扑CSN5(SUMO-CSN5)和 将SUMO-CSN5递送到未成熟的髓系促进JAK3的降解，这一过程是 对于髓系细胞的分化是必不可少的。这表明相扑-CSN5的生产是一个关键 外切体介导炎性细胞因子的致病步骤。在肝细胞中，ERK1/2激酶 被高脂喂养小鼠肝脏提取液上清液中的一种可溶性因子(S)激活，并导致 解离作为CSN5求和抑制因子的SENP1，从而促进生产 相扑-CSN5。这一过程被姜黄素抑制，姜黄素已知能抑制ERK1/2激活。因此， 我们假设，高脂饮食通过以下方式促进高水平相扑-CSN5外切体的产生 肝细胞；这些外切体被未成熟的髓系细胞摄取，导致SUMO-CSN5- 通过促进JAK3的降解而介导免疫抑制，从而促进肿瘤生长。我们 进一步假设，姜黄素处理导致抑制脑内CSN5相扑甲基化的处理。 通过抑制ERK1/2抑制高脂饮食喂养小鼠的肝细胞。这些假说将在体外得到验证 并在体内确定：(1)高脂肝细胞外切体中的Sumoylated CSN5是否对 活化的iMCs积聚与促进肝肿瘤进展；(2)ERK1/2信号通路 决定肝细胞中CSN5的脱氨基和苏氨酸化的平衡，并由一种 (3)高脂饮食诱导的肝细胞外切体介导的促肝肿瘤生长 通过使用新型可食用水果外切体作为靶向递送抗肿瘤药物的递送载体而可逆 炎症剂以炎性细胞治疗癌症。临床相关性。生成的数据 应该确定一种新的机制，将高脂饮食与炎症和免疫抑制反应联系起来 与肿瘤的发展相关，从而识别用于化疗或 化学预防。姜黄素水果外切体给药的安全性及其靶向研究 炎症细胞将是治疗这种令人衰弱的疾病的重要一步。

ABSTRACT The overall goal of this proposal is to study the role of hepatocyte exosomes in high fat diet mediated promotion of liver cancer development. Further, we will determine whether using novel edible fruit exosomes as a delivery vehicle for targetable delivery of an anti-inflammatory agent to tumor cells for treatment of liver cancer. Our preliminary data has indicated that hepatocyte exosomes are present in the peripheral blood of obese mice and obese individuals and the hepatocyte exosomes from mice fed a high-fat diet (HFD- exosomes) promote inflammatory responses and the growth of liver cancer in mouse model. These data implicate the production of hepatocyte exosomes in the inflammatory responses associated with liver cancer. Our preliminary data indicate that the HFD-exosomes carry high levels of sumoylated CSN5 (sumo-CSN5) and that the delivery of the sumo-CSN5 to immature myeloid promotes the degradation of Jak3, a process that is essential for differentiation of the myeloid cells. This pinpointed the production of the sumo-CSN5 as a critical pathogenic step in exosomes mediated Induction of inflammation cytokines. In hepatocyte cells, ErK1/2 kinase is activated by a soluble factor(s) from the supernatant of liver extracts of high fat-fed mice and causes the disassociation of Senp1 which acts as a suppressor of sumoylation of CSN5, thereby promoting the production of sumo-CSN5. This process is inhibited by curcumin, which is known to inhibit ErK1/2 activation. Therefore, we hypothesize that a high-fat diet promotes the production of exosomes with high levels of sumo-CSN5 by hepatocyte cells; that these exosomes are taken up by immature myeloid cells, resulting in sumo-CSN5- mediated immunosuppression by enhancing degradation of Jak3, and thus the promotion of tumor growth. We further hypothesize that curcumin treatment leads to the inhibition of processing of sumoylation of CSN5 in the hepatocyte cells from mice fed a high-fat diet by inhibition of ErK1/2. These hypotheses will be tested in vitro and in vivo to determine whether: (1) Sumoylated CSN5 in high-fat hepatocyte exosomes is essential for accumulation of activated iMCs and promotion of liver tumor progression; (2) The ErK1/2 signaling pathway determines the balance of desumoylation vs. sumoylation of CSN5 in hepatocyte cells and is promoted by a high-fat diet; and (3) the high-fat diet-induced hepatocyte exosome-mediated promotion of liver tumor growth is reversible by using novel edible fruit exosomes as a delivery vehicle for targetable delivery of an anti- inflammatory agent to inflammatory cells for treatment of cancer. Clinical Relevance. The data generated should identify a novel mechanism that links a high-fat diet to inflammatory and immunosuppressive responses associated with tumor development and thereby identify molecular targets for chemotherapy or chemoprevention. Demonstration of the safety of fruit exosomes-based delivery of curcumin and its targeting to inflammatory cells would be a significant step forward in the treatment of this debilitating disease.