肺瘤平膏通过XBP1介导的内质网应激-脂代谢途径逆转肿瘤相关树突状细胞功能的分子机制研究

Abnormal lipid accumulation could lead to the tumor-immunosuppression. Lipid accumulation induced by endoplasabmic reticulum stress reduced the antigen presenting ability of TDCs (tumor-associated dendritic cells) ,which could promote the formation of immunosuppression microenvironment. XBP1 is the main factor to connect endoplasmic reticulum stress and lipid metabolism, PI3K-AKT-mTOR signaling pathway is an important pathway of regulating lipid metabolism. Early research has shown that Feiliuping ointment could regulate metabolic pathways, including PI3K-AKT pathway. We hypothesized that Feiliuping ointment have a function on XBP1 mediated PI3K-AKT-mTOR signaling pathway, suppress endoplasmic reticulum stress, reduce lipid accumulation, and reshape the function of TDCs in the tumor microenvironment. This study tries to establish TDCs cultivation system, uses gene knockout technology, cell transfection, HPTLC and ESI-MS technique, in order to observe the effect of traditional Chinese medicine compound on TDCs (including lipid content, maturation and activation), reveal the action target (TDCs) on reversing immunosuppression of tumor microenvironment, the action link (reshaping the phenotype and function) and its mechanism (XBP1 mediated endoplasmic reticulum stress-lipid metabolism pathway), which provides the objective basis for the interpretation on specific regulation mechanism of traditional Chinese medicine.

脂质代谢异常可导致肿瘤免疫抑制，内质网应激诱导的脂质堆积造成了肿瘤相关树突状细胞（TDCs）抗原递呈功能降低，进而促进了免疫抑制微环境的形成。XBP1是连接内质网应激与脂代谢之间的桥梁，PI3K-AKT-mTOR信号通路是调控脂代谢的重要通路。前期研究结果显示，肺瘤平膏可调控代谢通路，其中PI3K-AKT通路是优势靶点。我们提出假说：肺瘤平膏通过作用于XBP1介导的PI3K-AKT-mTOR信号通路，减少脂质堆积，重塑肿瘤微环境中TDCs的功能。本研究拟建立TDCs培养体系，运用基因敲除、细胞转染、HPTLC、ESI-MS等技术，观察中药复方对 TDCs（脂质含量、成熟、活化）的影响，揭示其逆转肿瘤免疫抑制微环境的作用靶点（TDCs）、作用环节（重塑表型及功能）及其作用机制（XBP1介导的内质网应激-脂代谢途径），为阐释中药特异性调控肿瘤免疫功能的作用机制提供客观依据。

脂质代谢异常可导致肿瘤免疫抑制，内质网应激诱导的脂质堆积造成了肿瘤相关树突状细胞(TDCs)抗原递呈功能降低，进而促进了免疫抑制微环境的形成。XBP1是连接内质网应激与脂代谢之间的桥梁，PI3K-AKT-mTOR信号通路是调控脂代谢的重要通路。前期研究结果显示，肺瘤平膏可调控代谢通路，其中PI3K-AKT通路是优势靶点。本研究在前期研究基础上，利用细胞转染技术构建XBP1过表达Lewis肺癌荷瘤小鼠，以及利用毒胡萝卜素激活内质网应激构建XBP1-s剪切TDCs体外培养模型，运用FACS、RT-PCR、WB等技术，动态观察肺瘤平膏对减少TDCs脂质堆积，重塑TDCs表型及功能的影响，从XBP1介导的PI3K-AKT-mTOR信号通路入手，揭示其逆转肿瘤免疫抑制微环境的作用靶点（TDCs）、作用环节（重塑表型及功能）及其作用机制（XBP1介导的内质网应激-脂代谢途径），为阐释中药特异性调控肿瘤免疫功能的作用机制提供了客观依据。