1.cGAS: Its Canonical and Non-canonical Functions
Wen-Xian ZHENG ; Meng-Jie XIONG ; Shu-Ting JIA ; Ruo-Yu ZHOU
Progress in Biochemistry and Biophysics 2026;53(5):1279-1296
Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.
2.cGAS: Its Canonical and Non-canonical Functions
Wen-Xian ZHENG ; Meng-Jie XIONG ; Shu-Ting JIA ; Ruo-Yu ZHOU
Progress in Biochemistry and Biophysics 2026;53(5):1279-1296
Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.
3.Preparation of anisamide-modified ursolic acid self-assembled nanoparticles and their anti-drug resistance effect of enzalutamide on prostate cancer via regulation of CAFs
Ling-xi CHEN ; Shu-ting NI ; Wen-yang ZHAO ; Lei CHEN ; Kai-li HU
Chinese Traditional Patent Medicine 2025;47(1):28-35
AIM To prepare anisamide-modified ursolic acid self-assembled nanoparticles,and to evaluate their anti-drug resistance effect of enzalutamide on prostate cancer.METHODS Nanoparticle precipitation method was adopted in the preparation of anisamide-modified and non-anisamide-modified self-assembled nanoparticles,respectively,after which the particle size,Zeta potential and encapsulation efficiency were determined,and the morphology was observed under transmission electron microscope.The intake of cancer-associated fibroblasts(CAFs)was investigated,after which the model for enzalutamide resistance in prostate cancer was established,CCK8 assay was applied to analyzing the sensitization effect of self-assembled nanoparticles on enzalutamide,and Western blot was used for the detection of NRG1,HER3,AKT expressions.RESULTS The anisamide-modified self-assembled nanoparticles demonstrated the average particle size,Zeta potential and encapsulation efficiency of(195.13±8.06)nm,(-29.07±0.55)mV and(94.58±0.84)%,respectively.CAFs displayed higher intake in the anisamide-modified self-assembled nanoparticles than that in the non-modified preparation and free Cy5(P<0.05).Meanwhile,anisamide-modified self-assembled nanoparticles were able to inhibit enzalutamide resistance caused by CAFs,reduce NRG1 expression on CAFs,and anisamide-modified self-assembled nanoparticles-treated conditioned medium of CAFs could reduce HER3 and AKT expression on LNCaP cells(P<0.05,P<0.01).CONCLUSION Anisamide-modified ursolic acid self-assembled nanoparticles can enhance the targeting of CAFs,alleviate the drug resistance effect of enzalutamide on prostate cancer caused by CAFs,and reduce NRG1 expression in CAFs.
4.Ursodeoxycholic acid inhibits the uptake of cystine through SLC7A11 and impairs de novo synthesis of glutathione
Fu'an XIE ; Yujia NIU ; Xiaobing CHEN ; Xu KONG ; Guangting YAN ; Aobo ZHUANG ; Xi LI ; Lanlan LIAN ; Dongmei QIN ; Quan ZHANG ; Ruyi ZHANG ; Kunrong YANG ; Xiaogang XIA ; Kun CHEN ; Mengmeng XIAO ; Chunkang YANG ; Ting WU ; Ye SHEN ; Chundong YU ; Chenghua LUO ; Shu-Hai LIN ; Wengang LI
Journal of Pharmaceutical Analysis 2025;15(1):189-207
Ursodeoxycholic acid(UDCA)is a naturally occurring,low-toxicity,and hydrophilic bile acid(BA)in the human body that is converted by intestinal flora using primary BA.Solute carrier family 7 member 11(SLC7A11)functions to uptake extracellular cystine in exchange for glutamate,and is highly expressed in a variety of human cancers.Retroperitoneal liposarcoma(RLPS)refers to liposarcoma originating from the retroperitoneal area.Lipidomics analysis revealed that UDCA was one of the most significantly down-regulated metabolites in sera of RIPS patients compared with healthy subjects.The augmentation of UDCA concentration(≥25 μg/mL)demonstrated a suppressive effect on the proliferation of liposarcoma cells.[15N2]-cystine and[13Cs]-glutamine isotope tracing revealed that UDCA impairs cystine uptake and glutathione(GSH)synthesis.Mechanistically,UDCA binds to the cystine transporter SLC7A11 to inhibit cystine uptake and impair GSH de novo synthesis,leading to reactive oxygen species(ROS)accumulation and mitochondrial oxidative damage.Furthermore,UDCA can promote the anti-cancer effects of ferroptosis inducers(Erastin,RSL3),the murine double minute 2(MDM2)inhibitors(Nutlin 3a,RG7112),cyclin dependent kinase 4(CDK4)inhibitor(Abemaciclib),and glutaminase inhibitor(CB839).Together,UDCA functions as a cystine exchange factor that binds to SLC7A11 for antitumor activity,and SLC7A11 is not only a new transporter for BA but also a clinically applicable target for UDCA.More importantly,in combination with other antitumor chemotherapy or physiotherapy treatments,UDCA may provide effective and promising treatment strategies for RLPS or other types of tumors in a ROS-dependent manner.
5.Preparation of anisamide-modified ursolic acid self-assembled nanoparticles and their anti-drug resistance effect of enzalutamide on prostate cancer via regulation of CAFs
Ling-xi CHEN ; Shu-ting NI ; Wen-yang ZHAO ; Lei CHEN ; Kai-li HU
Chinese Traditional Patent Medicine 2025;47(1):28-35
AIM To prepare anisamide-modified ursolic acid self-assembled nanoparticles,and to evaluate their anti-drug resistance effect of enzalutamide on prostate cancer.METHODS Nanoparticle precipitation method was adopted in the preparation of anisamide-modified and non-anisamide-modified self-assembled nanoparticles,respectively,after which the particle size,Zeta potential and encapsulation efficiency were determined,and the morphology was observed under transmission electron microscope.The intake of cancer-associated fibroblasts(CAFs)was investigated,after which the model for enzalutamide resistance in prostate cancer was established,CCK8 assay was applied to analyzing the sensitization effect of self-assembled nanoparticles on enzalutamide,and Western blot was used for the detection of NRG1,HER3,AKT expressions.RESULTS The anisamide-modified self-assembled nanoparticles demonstrated the average particle size,Zeta potential and encapsulation efficiency of(195.13±8.06)nm,(-29.07±0.55)mV and(94.58±0.84)%,respectively.CAFs displayed higher intake in the anisamide-modified self-assembled nanoparticles than that in the non-modified preparation and free Cy5(P<0.05).Meanwhile,anisamide-modified self-assembled nanoparticles were able to inhibit enzalutamide resistance caused by CAFs,reduce NRG1 expression on CAFs,and anisamide-modified self-assembled nanoparticles-treated conditioned medium of CAFs could reduce HER3 and AKT expression on LNCaP cells(P<0.05,P<0.01).CONCLUSION Anisamide-modified ursolic acid self-assembled nanoparticles can enhance the targeting of CAFs,alleviate the drug resistance effect of enzalutamide on prostate cancer caused by CAFs,and reduce NRG1 expression in CAFs.
6.Exploration of the Application of Generative Artificial Intelligence to the Challenge of Medical Record Writing
Xiaoyuan GAO ; Xiaolin DIAO ; Fan XU ; Hongxia LI ; Xintong WU ; Zixing WANG ; Wei ZHAO ; Ting SHU
Chinese Hospital Management 2025;45(5):76-79
Generative Artificial Intelligence ishows a broad application prospect in the field of healthcare and has become an important technical means to promote the development of medical informatization.It addresses the multi-faceted challenges of medical record documentation,including efficiency,quality,and doctor-patient communica-tion.It analyzes the adaptability and feasibility of Generative Artificial Intelligence in different clinical scenarios of intelli-gent medical record generation.Additionally,it explores the issues present in current applications and proposes corre-sponding solutions,providing references for the effective application and continuous optimization of Generative Artifi-cial Intelligence in medical record documentation.This provides a theoretical foundation for further expanding the appli-cation scenarios of automatic medical record documentation in China's healthcare industry.
7.Associations of high-sensitivity C-reactive protein and T cells with cognitive impairment
Xianzhi YANG ; Shu ZHANG ; Xuexuan GU ; Mingqing WEI ; Ting LI ; Jingnian NI ; Jing SHI ; Jinzhou TIAN
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2025;27(4):408-411
Objective To investigate the associations of immune cells,CD8+and CD4+T cells,and high-sensitivity C-reactive protein(hs-CRP)with cognitive function,and to explore the relation-ships among immunity,chronic inflammation,and Alzheimer's disease-related cognitive impair-ment.Methods A cross-sectional study was conducted on 101 patients with primary complaints of memory decline who visited the Alzheimer's Disease Clinic of Dongzhimen Hospital from June to December 2024.Mini-Mental State Examination(MMSE)and Delayed Story Recall Task(DSR)were performed to assess their cognitive function,and according to the results,they were divided into observation group(cognitively impaired,60 cases)and control group(cognitively normal,41 cases).Peripheral blood levels of CD8+T cells,CD4+T cells,and hs-CRP were compared between the two groups.Results The observation group exhibited significantly lower total scores and scores of different dimensions of MMSE and DSR scores,but notably higher activities of daily liv-ing scores than the control group(P<0.05,P<0.01).Serum hs-CRP level was obviously elevated in the observation group than the control group(P<0.05).Binary logistic regression analysis revealed that CD8+T cells(OR=0.998,95%CI:0.996-1.000,P=0.038)and body mass index(OR=0.843,95%CI:0.719-0.990,P=0.037)were protective factors,while hs-CRP(OR=2.004,95%CI:1.215-3.306,P=0.006)was an independent risk factor for cognitive impairment.Spearman's rank correlation analysis showed a significant positive correlation between hs-CRP and CD4+T cells(P=0.011),but no significant association with CD8+T cells(P>0.05).Conclusion Chronic inflammation and immune dysregulation synergistically contribute to cogni-tive decline.Hs-CRP may serve as a potential screening biomarker for cognitive impairment in pri-mary care settings.
8.A case report of premature ovarian insufficiency caused by a novel FANCL mutation(c.1033G>A)and in vitro functional validation
Yi-qing LIU ; Shu-ting REN ; Yun-cheng PAN ; Feng ZHANG ; Xiao-jin ZHANG ; Yan-hua WU
Fudan University Journal of Medical Sciences 2025;52(2):270-276,291
Objective To investigate the characteristics of a novel FANCL mutation identified in a patient with premature ovarian insufficiency(POI)and to explore its potential functional impacts in vitro.Methods A novel FANCL heterozygous mutation c.1033G>A(p.Glu345Lys)was screened in a patient with POI using whole exome sequencing(WES),which was found to be inherited from a mother who had undergone early menopause.The authenticity of the mutation was identified by Sanger sequencing and the conserved nature of the mutation site was predicted by software.Overexpressing FANCL mutant and wildtype plasmids were constructed and transiently transfected into HEK293T cell lines,and the effect of the mutation was detected by qPCR,immunofluorescence and Western blot.Results The mutation site of FANCL was located within the Ring domain of FANCL,which was highly conserved across multiple species.The mutant showed no significant change in mRNA expression level,while the protein expression level was significantly down-regulated.In vitro cellular experiments further revealed that the mutation leads to decreased expression levels by reducing protein stability.Conclusion A FANCL c.1033G>A mutation was found and it may cause disease in the POI patient due to decreased protein stability.
9.Research advances in mitochondrial inflammation-mediated damage in central nervous system degenerative disorders
Shu-qin LI ; Sha-sha LIU ; Qian YAN ; Han-long WANG ; Yang SUN ; Yan-ting HUANG ; Hao-jie ZHANG ; Jin-ping LIANG ; Shi-feng CHU ; Yan-tao YANG ; Qi-di AI ; Nai-hong CHEN
Chinese Pharmacological Bulletin 2025;41(12):2218-2225
Central nervous system(CNS)degenerative disorders refer to a spectrum of pathological alterations triggered by struc-tural damage to cerebral neural tissues,clinically manifested as diverse neurological dysfunction syndromes,including multiple sclerosis(MS),neurodegenerative diseases(NDs),and ische-mic stroke.The hallmark pathological features of these disorders involve irreversible neuronal damage and decompensation of functional neural networks,ultimately leading to progressive neurological deficits.Notably,with the accelerating global popu-lation aging,the incidence of these diseases has surged signifi-cantly.According to WHO statistics,they now rank among the top three global causes of disability and mortality.Current re-search has confirmed that the pathogenesis of CNS degenerative disorders exhibits high heterogeneity,encompassing multifaceted pathophysiological processes such as genetic predisposition,oxi-dative stress,protein misfolding,and metabolic dysregulation.This intricate pathogenic network not only complicates clinical differential diagnosis but also poses substantial challenges to the development of precision therapeutic strategies.Importantly,re-cent studies have revealed that mitochondrial homeostasis disrup-tion-induced inflammatory cascades(termed mitochondrial in-flammation)play a pivotal regulatory role in neurodegenerative progression.Key molecular mechanisms include impaired mito-phagy,aberrant mitochondrial DNA(mtDNA)release and NL-RP3 inflammasome activation.This review systematically deci-phers the molecular regulatory network of mitochondrial inflam-mation,with a focus on its biological effects in critical pathologi-cal events such as blood-brain barrier disruption,microglial hy-peractivation and neuronal apoptosis.The overarching aim is to provide a theoretical foundation for developing innovative thera-peutic strategies targeting mitochondrial homeostasis restoration.
10.Analgesic effect of ultrasound-guided quadratus lumborum block combined with patient-controlled intravenous analgesia after lower abdominal surgery
Shu-ting LI ; Tan-guang WU ; Guo-jiang YIN ; Kun LI ; Xiao-yang SONG
Journal of Regional Anatomy and Operative Surgery 2025;34(10):904-907
Objective To investigate the analgesic effect of ultrasound-guided quadratus lumborum block combined with patient-controlled intravenous analgesia after lower abdominal surgery.Methods A total of 134 patients who underwent lower abdominal surgery in General Hospital of Central Theater Command from April 2021 to April 2024 were prospectively selected and randomly divided into the observation group and the control group,with 67 patients in each group.Patients in the observation group received ultrasound-guided quadratus lumborum block combined with patient-controlled intravenous analgesia.Patients in the control group underwent only patient-controlled intravenous analgesia.The number of analgesic pump compressions and the cumulative sufentanil consumption 4 hours,6 hours,12 hours,and 24 hours after surgery,the visual analogue score(VAS)of pain at rest and exercise,and the incidence of adverse reactions during postoperative analgesia were compared between the two groups.Results Compared with the control group,the number of analgesic pump compressions and the cumulative sufentanil consumption of patients were fewer/less at 6 hours,12 hours and 24 hours after surgery in the observation group(P<0.05).The VAS scores of patients at exercise 4 hours,6 hours,12 hours and 24 hours after surgery in the observation group were significantly lower than those in the control group(P<0.05).The incidence of nausea,vomiting and vertigo in the observation group was significantly lower than that in the control group(P<0.05).Conclusion Compared with patient-controlled intravenous analgesia,ultrasound-guided quadratus lumborum block combined with patient-controlled intravenous analgesia can significantly reduce the number of analgesia pump compressions and the cumulative sufentanil consumption in postoperative analgesia of lower abdominal surgery,and has a better effect in relieving exercise pain,it can also reduce the occurrence of adverse reactions such as nausea and vomiting.

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