环状GMP-AMP合成酶（cyclic GMP-AMP synthase，cGAS）是近几年发现的一种新的DNA模式识别受体，通过将信号2’-3’环化二核苷酸（cyclic GMP-AMP，cGAMP）传递至接头蛋白干扰素刺激蛋白（stimulator of interferon genes，STING）激活固有免疫系统，从而发挥抵抗病毒感染的作用。近年来，研究发现cGAS-cGAMP-STING信号通路可通过识别自身DNA诱导无菌性炎性反应从而参与急性肾损伤、免疫性肾病及肾脏肿瘤的发生，可为该类疾病的药物研发提供新的靶点。本文系统综述了cGAS-cGAMP-STING信号通路的发现、蛋白结构与功能及其在肾脏疾病中的作用，探讨了cGAS-cGAMP-STING信号通路在肾脏疾病治疗方面的意义。

cGAS-cGAMP-STING信号通路是固有免疫系统重要组成部分，通过识别胞浆DNA诱导I型干扰素(interferons，IFNs)和其他细胞因子产生，介导抗微生物先天免疫，同时也在肿瘤进展及远处转移中发挥作用。深入了解cGAS-cGAMP-STING信号通路与炎症性疾病、自身免疫性疾病及肿瘤发生发展的关系，以及STING激动剂的研究现状等，将对临床相关疾病的治疗方案给予理论支持，也将对开发cGAS-cGAMP-STING信号通路的抗肿瘤靶向药物提供新的启示。

Sepsis is a life-threatening clinical syndrome and one of the most challenging health problems in the world. Pathologically, sepsis and septic shock are caused by a dysregulated host immune response to infection, which can eventually lead to multiple organ failure and even death. As an adaptor transporter between the endoplasmic reticulum and Golgi apparatus, stimulator of interferon response cGAMP interactor 1 (STING1, also known as STING or TMEM173) has been found to play a vital role at the intersection of innate immunity, inflammation, autophagy, and cell death in response to invading microbial pathogens or endogenous host damage. There is ample evidence that impaired STING1, through its immune and non-immune functions, is involved in the pathological process of sepsis. In this review, we discuss the regulation and function of the STING1 pathway in sepsis and highlight it as a suitable drug target for the treatment of lethal infection.

环鸟苷酸-腺苷酸合成酶(cGAS)-干扰素基因刺激因子(STING)信号通路是STING激活的经典途径，其在激发天然免疫方面的作用近年来逐渐被广泛关注。cGAS可识别并结合内源性或外源性DNA，催化三磷酸腺苷(ATP)和三磷酸鸟苷(GTP)合成环鸟苷酸-腺苷酸(cGAMP)，继而激活STING信号，促进Ⅰ型干扰素(IFN)和炎性因子的产生，诱导天然免疫和适应性免疫。现有研究表明，cGAS-STING信号通路在感染、炎症、肿瘤等的治疗中发挥着重要作用，尤其是在临床治疗效果欠佳的高级别胶质瘤的治疗中也有着巨大潜力。本文将对cGAS-STING信号通路做简要概述并总结其在脑肿瘤中的作用及机制，以期为脑肿瘤治疗靶点和治疗药物的发掘提供新思路。

目的:研究粉防己碱是否可以联合cGAMP作为cGAMP的激动剂增强cGAS-STING信号通路，从而探究粉防己碱的抗病毒功能。方法:采用不同浓度的粉防己碱联合cGAMP分别处理THP1-Lucia-ISRE及RAW-Lucia-ISRE细胞，荧光素酶报告试验探究IRF3免疫应答水平；Western blot检测cGAS-STING信号通路激活情况；实时荧光定量PCR检测IFN-β、CXCL10及CCL5的mRNA表达水平；ELISA检测IFN-β表达情况。构建稳定表达STING-GFP基因的HeLa细胞(HeLa-STNG-GFP)，粉防己碱联合cGAMP处理该细胞后，观察STING-GFP点聚集现象。Ⅰ型疱疹病毒(herpes simplex virus type 1，HSV-1)感染THP1-Lucia-ISG细胞，粉防己碱联合cGAMP处理细胞，Western blot及荧光强度探究粉防己碱的抗病毒能力。结果:粉防己碱能够增强cGAMP介导的IRF3免疫应答，与cGAMP联用可激活cGAS-STING信号通路。粉防己碱联合cGAMP处理HeLa-STNG-GFP细胞后，观察到明显的STING-GFP点聚集现象。对感染HSV-1的THP1-Lucia-ISG细胞进行粉防己碱联合cGAMP孵育，HSV-1病毒滴度、HSV-糖蛋白D/UL30的表达及HSV-GFP荧光强度均显著下降。结论:粉防己碱联合cGAMP可激活cGAS-STING信号通路从而增强宿主的抗病毒反应。

肿瘤免疫疗法通过调节先天免疫和适应性免疫系统来对抗肿瘤。环鸟苷酸-腺苷合成酶(cGAS)是外源性和内源性DNA先天免疫应答的关键调节因子。cGAS识别胞质DNA后，产生第二信使cGAMP，随后与激活干扰素调节因子3接头蛋白STING(也被称为MITA、MPYS和ERIS)结合诱导产生Ⅰ型干扰素和炎性细胞因子来介导抗先天免疫。最近的研究阐释了该通路能被来自肿瘤自身的DNA和基因组不稳定性副产物激活并影响肿瘤发生发展，在天然抗肿瘤免疫及免疫检查点阻滞治疗中起关键作用。本综述概述了在肿瘤中对cGAS-STING信号通路的认识，强调了其在肿瘤免疫和放疗中的重要作用，以及针对该通路的潜在靶向或替代治疗方法。

环化核苷酸合成酶（cGAS）是一种DNA感受器，通过环鸟苷酸-腺苷酸（cGAMP）将信号传递给干扰素刺激因子（STING），诱导下游通路产生一系列免疫及炎症反应。近年的研究表明，cGAS-STING信号通路在肺部感染性疾病、肺癌、特发性肺纤维化、慢性阻塞性肺疾病、支气管哮喘和急性肺损伤等多种呼吸系统疾病的发生发展中发挥重要作用，为呼吸系统疾病的诊断和治疗提供了新的靶点。本文综述了cGAS-STING信号通路及其在呼吸系统疾病研究中的最新进展。

目的 研究cGAMP对小鼠脑缺血恢复期的影响及初步作用机制.方法 采用线栓法制备小鼠大脑中动脉闭塞(MCAO)模型,通过行为学评分和组织病理染色观察cGAMP对MCAO小鼠恢复期的影响.激光散斑仪器观察cGAMP对MCAO小鼠恢复期的脑血流量的影响,使用苏木精-伊红染色(HE)和尼氏染色(NISSL)观察cGAMP对MCAO小鼠大脑皮层神经元的影响,使用实时荧光定量聚合酶链反应(PCR)检测小鼠大脑皮层中肿瘤坏死因子α(TNF-α)和精氨酸酶1(Arg-1)的表达,使用蛋白免疫印迹法(Western blot)检测小鼠大脑皮层中PI3K、p-PI3K、AKT、p-AKT的表达.结果 行为学观察结果显示,与模型组相比,缺血期的MCAO小鼠经cGAMP处理后,行为学评分降低,在提尾测试、平衡木试验和前肢抓地力牵引测试中,其运动功能均显著恢复.HE、NISSL染色中,cGAMP可减轻脑缺血恢复期小鼠神经元损伤.PCR结果表明cGAMP处理可以降低脑缺血恢复期小鼠脑组织TNF-α的表达,升高Arg-1的表达.在Western blot结果中,cGAMP处理能够显著促进PI3K、AKT的磷酸化(P＜0.05).结论 cGAMP能明显改善脑缺血恢复期小鼠运动功能,可能是通过激活PI3K-AKT通路减轻小鼠脑缺血恢复期的神经元损伤发挥治疗作用.

The innate immune system protects the host from external pathogens and internal damage in various ways.The cGAS-STING signaling pathway,comprised of cyclic GMP-AMP synthase(cGAS),stimulator of interferon genes(STING),and downstream signaling adaptors,plays an essential role in protective immune defense against microbial DNA and internal damaged-associated DNA and is responsible for various immune-related diseases.After binding with DNA,cytosolic cGAS undergoes conformational change and DNA-linked liquid-liquid phase separation to produce 2'3'-cGAMP for the activation of endoplasmic reticulum(ER)-localized STING.However,further studies revealed that cGAS is predominantly expressed in the nucleus and strictly tethered to chromatin to prevent binding with nuclear DNA,and functions differently from cytosolic-localized cGAS.Detailed delineation of this pathway,including its structure,signaling,and regulatory mechanisms,is of great significance to fully understand the diversity of cGAS-STING activation and signaling and will be of benefit for the treatment of inflammatory diseases and cancer.Here,we review recent progress on the above-mentioned perspectives of the cGAS-STING signaling pathway and discuss new avenues for further study.

Biomolecular condensates formed by phase separation are widespread and play critical roles in many physiological and pathological processes.cGAS-STING signaling functions to detect aberrant DNA signals to initiate anti-infection defense and antitumor immunity.At the same time,cGAS-STING signaling must be carefully regulated to maintain immune homeostasis.Interestingly,exciting recent studies have reported that biomolecular phase separation exists and plays important roles in different steps of cGAS-STING signaling,including cGAS condensates,STING condensates,and IRF3 condensates.In addition,several intracellular and extracellular factors have been proposed to modulate the condensates in cGAS-STING signaling.These studies reveal novel activation and regulation mechanisms of cGAS-STING signaling and provide new opportunities for drug discovery.Here,we summarize recent advances in the phase separation of cGAS-STING signaling and the development of potential drugs targeting these innate immune condensates.