CD47-SIRPα调控的巨噬细胞吞噬功能在情志因素诱发肿瘤易感性中的作用研究

In traditional Chinese medicine, the development of cancer is suggested to associate with emotional factor, however its molecular biological mechanism remains unknown. Besides, it is difficult to explain the antitumor effects of traditional Chinese medicines which are effective in clinic. The reason is closely relative to the lack of emotional factor in the animal and cellular models. Our previously studies suggested that emotional stress could increase the metastasis of tumor in restrain mice, which is possibly associated with a molecular biological mechanism that corticosterone (CORT), a stress hormone, inhibits the phagocytosis in macrophages and promotes the tumor immune escape through up-regulating the interaction of CD47-SIRPα, a don’t eat me signal between macrophage and tumor. Therefore, tumor susceptibility model and CORT-induced macrophages stress model are established and the phagocytosis of macrophages and the interaction of CD47-SIRPα are studied by Caliper IVIS Lumina II, knockout mice, RNA Interference and live cell imaging system. Furthermore, the pathogenesis of tumor is determined by H&E and immunohistochemistry, and the expression of gene and protein in CD47-SIRPα pathway are determined by Western Blotting and qRT-PCR. On the basis of the above models, the intervention effect and the mechanism of classical anti-tumor formulas aiming to “Reinforcing Qi and Nourishing Yin”, “Relief liver for smooth Qi” and “Softening hardness to dissipate stagnation” are explored in single or in combination. In summary, we aim to explain the role of emotional factor in classical theory of traditional Chinese medicine by western medicine, and to provide an effective screen and evaluation method for traditional Chinese medicine in treating cancers.

中医指出乳岩、噎膈等肿瘤的发生与情志因素有关，但生物学机制不明确，中药抗肿瘤作用及机制研究也陷入瓶颈，这与现有评价模型缺乏对情志因素的考察有关。基于中医情志致病学说与现代医学心理应激致病理论的一致性，本项目前期研究采用心理应激模拟情志刺激，结果提示应激能促进小鼠肿瘤转移，机制可能与应激激素CORT通过上调CD47-SIRPα介导的“don’t eat me signal”抑制巨噬细胞吞噬功能、形成免疫逃逸有关。为验证该假说，本项目拟基于应激建立的肿瘤易感动物模型与CORT巨噬细胞应激模型，采用小动物活体成像、基因敲除、RNAi和活细胞工作站等技术研究CD47-SIRPα通路在情志应激干预巨噬细胞吞噬功能中的作用。基于以上模型，进一步研究以“益气养阴、疏肝理气”等为治则的中药复方单独或配伍的干预作用及机理。旨在揭示中医情志致病的科学内涵，建立和拓展符合中药抗肿瘤作用特点的药效筛选与评价方法。

中医理论指出肿瘤的发生与情志因素干预有关，但长期以来有关情志刺激诱发肿瘤易感性的生物学机制研究甚少，中药抗肿瘤作用及其机制研究也陷入瓶颈，这与现有评价模型缺乏对情志因素的考察有关。基于中医情志致病学说与现代医学心理应激致病理论的一致性，本研究拟确立情志应激和多种肿瘤（肝癌、卵巢癌、乳腺癌）易感性的关联性，从巨噬细胞吞噬信号的调控角度探讨情志应激增加肿瘤生长的生物学机制。其次，拟利用肿瘤易感模型研究疏肝解郁经典名方作用及机理。基于以上研究背景和研究目标，我们开展了一系列研究工作，取得了以下结果：. 首先，我们通过多个肿瘤（P815肝癌、SKOV3卵巢癌、4T1乳腺癌、MDA-MB-231乳腺癌）模型确定了应激诱导肿瘤易感性与CORT的关系；其次以情志应激增加乳腺癌易感性为重点研究对象，探讨了巨噬细胞的吞噬功能的紊乱在发病机制中的重要作用。在项目实施过程中，我们发现应激/应激激素CORT增强了CD47-SIRPα介导的“别吃我”信号。进一步，我们发现情志应激增强CD47-SIRPα“别吃我”信号与抑制CALR-LRP1“吃我”信号有关。通过以上机制，情志应激紊乱了巨噬细胞上“吃我”-“别吃我”信号受体的平衡，抑制巨噬细胞对肿瘤细胞的吞噬。因此，我们后期实验过程中重点研究了“吃我”-“不吃我”信号受体（LRP1-SIRPα）在应激条件下巨噬细胞吞噬肿瘤细胞中的作用以及其调控机制。最后，本项目评价和对比了疏肝解郁经典方“逍遥散”、“柴胡疏肝散”、“益气养阴汤”、“鳖甲煎丸”对应激小鼠乳腺癌生长的抑制作用，并以疗效最佳的逍遥散为代表，探讨了疏肝解郁方对巨噬细胞吞噬信号和吞噬功能的作用。.本项目以情志应激建立肿瘤易感性模型，探讨了情志因素诱发肿瘤易感性的生物学机制，用现代医学思路和方法诠释中医情志致病理论的科学内涵，建立和拓展了适合中药药效的筛选与评价方法的共性技术，为中医药防治肿瘤的研究提供科学依据。