Mechanism of cGAS/STING Signaling Pathway in Regulating Lung Cancer and Traditional Chinese Medicine Treatment： A Review / 中国实验方剂学杂志

According to the latest global cancer statistics， the incidence and mortality of lung cancer rank first in China. Classical therapies remain the most common cancer treatment options， such as surgical resection， radiotherapy， and chemotherapy， but not all cancer patients respond to classical therapies， which require new lung cancer treatment strategies. After decades of research and development， cancer immunotherapy has achieved certain curative effect， which provides new possibilities for cancer treatment. Cyclic guanosine monophosphate-adenosine monophosphate synthase （cGAS） is a cytosolic DNA sensor. It can induce protective immune defense responses against various DNA-containing pathogens and provide anti-tumor immunity by activating the interferon （IFN） gene stimulator （STING） protein. At present， relevant researchers in China and abroad have done a lot of research on the occurrence and development of lung cancer and the pathophysiological mechanism of drug intervention in the treatment of lung cancer. The results show that cGAS/STING signaling pathway plays an important role in the development of the disease， and traditional Chinese medicine monomers or compounds can intervene in lung cancer cells by regulating the cGAS/STING signaling pathway， induce their autophagy and death， regulate their cycle operation， promote senescence， inhibit their proliferation and tumor angiogenesis， promote their invasion and metastasis， and promote the immune activation of anti-lung cancer cells， so as to inhibit or delay the occurrence and development of lung cancer. In recent years， the related research results have been updated rapidly， and the previous literature has not included the latest research results in time， which causes a lot of inconvenience for many scholars to search the literature. Based on this， this paper mainly summarized the mechanism of cGAS/STING signaling pathway intervention in lung cancer in China and abroad in recent years， as well as the research progress of related traditional Chinese medicine intervention， so as to provide new ideas for the development of lung cancer in molecular biology， drug treatment research， and clinical new drug research and provide a reference for further mechanism research.

Effect Mechanism of Modified Baitouwengtang Treating Colorectal Cancer by Regulating CSF1R/STING/TBK1 Signaling to Polarize Phenotype of Tumor-associated Macrophages （TAMs） / 中国实验方剂学杂志

ObjectiveThis study aims to investigate the effect of modified Baitouwengtang （MBTWD） on tumor growth and the number of tumor-associated macrophages （TAMs） in tumor tissue of MC38 cell tumor-bearing mice with colorectal cancer and explores whether MBTWD mediates the remodeling of TAM phenotype to play an immunologically antitumor effect. MethodFirstly， The C57BL/6 mouse tumor model grafted subcutaneously was established， and then model mice were classified into a model group， positive control group（3 mg·kg-1）， and MBTWD groups with high and low dosages（23.43、46.86 g·kg-1）， with 10 mice in each group. In addition， 10 healthy mice were set as the blank group， and the changes in body weight， tumor volume， and survival status of mice in each group were observed. Tumor tissue， spleen， and peripheral blood were collected to calculate the tumor volume change， tumor inhibition rate， and spleen mass. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of tumor tissue， and an immunofluorescence assay was used to detect the expression levels of CD4， CD8， and CD206 in tumor tissues of tumor-bearing mice. The secretion levels of transforming growth factor （TGF）-β， interleukin （IL）-6， and chemokine （C-C Motif） ligand 2 （CCL2） in peripheral serum were measured by using enzyme-linked immunosorbent assay （ELISA）. Secondly， a co-culture model induced by IL-4 in vitro of MC38 cells and murine monocytic macrophage RAW264.7 cells was established. Cell proliferation and activity assay （CCK-8） was used to detect the inhibitory effect of MBTWD containing serum on cell proliferation. A transwell experiment was used to detect the effect of IL-4-induced M2 macrophages on the invasion of MC38 cells. Flow cytometry was used to detect the expression of CD86 on the membrane of M2 macrophages induced by IL-4 with MBTWD containing serum. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the effect of MBTWD containing serum on the mRNA expression levels of M1 macrophage-related polarization factors CD86， nitric oxide synthase （iNOS）， and IL-12， as well as M2 macrophage-related polarization factors CD206， CD163， and IL-10 after co-cultivation. Finally， the protein expression levels of colony-stimulating factor 1 receptor （CSF1R）， stimulator of interferon genes （STING）， and TANK binding kinase 1 （TBK1） in tumor tissues of tumor-bearing mice were detected by Western blot. ResultIn vivo experimental results show that compared with the model group， the MBTWD can significantly inhibit the tumor growth of tumor-bearing mice. Immunofluorescence experiments show that the MBTWD can increase the number of CD8+ T cell infiltration in tumor tissue of tumor-bearing mice， reduce the number of CD206+ TAMs infiltration， and down-regulate the secretion levels of cytokines IL-6， TGF-β， and CCL2 in peripheral blood of tumor-bearing mice. The results of in vitro experiments show that the MBTWD containing serum has no obvious inhibitory effect on cell proliferation， but the cell supernatant after co-cultivation with RAW264.7 cells can inhibit the proliferation activity of MC38 cells， and the invasion ability of MC38 cells is enhanced by IL-4-induced M2 macrophages. However， this effect can be inhibited in a concentration-dependent manner by the MBTWD containing serum. At the same time， the results of Real-time PCR show that the MBTWD containing serum can up-regulate the mRNA expression levels of M1 macrophage-related polarization factors CD86， iNOS， and IL-12 and down-regulate those of M2 macrophage-related polarization factors CD206， CD163， and IL-10. Flow cytometry results also confirm that the MBTWD containing serum can increase the number of repolarized CD86+ M1 macrophages， indicating that MBTWD can induce M2 macrophages to repolarized M1 macrophages to play an anti-tumor growth role. Finally， Western blot results show that MBTWD can down-regulate the expression of CSF1R protein and up-regulate that of STING and TBK1 proteins in tumor tissue of tumor-bearing mice. ConclusionMBTWD can down-regulate the infiltration number of CD206+ TAMs and increase the infiltration of CD8+ T cells， thereby playing an immunologically antitumor effect on the growth inhibition of colorectal cancer， which may be related to regulating CSF1R signaling and then activating STING/TBK1 signaling pathway to induce phenotypic remodeling of TAMs.

Novel STING-targeted PET radiotracer for alert and therapeutic evaluation of acute lung injury

Acute lung injury (ALI), as a common clinical emergency, is pulmonary edema and diffuse lung infiltration caused by inflammation. The lack of non-invasive alert strategy, resulting in failure to carry out preventive treatment, means high mortality and poor prognosis. Stimulator of interferon genes (STING) is a key molecular biomarker of innate immunity in response to inflammation, but there is still a lack of STING-targeted strategy. In this study, a novel STING-targeted PET tracer, [18F]FBTA, was labeled with high radiochemical yield (79.7 ± 4.3%) and molar activity (32.5 ± 2.9 GBq/μmol). We confirmed that [18F]FBTA has a strong STING binding affinity (Kd = 26.86 ± 6.79 nmol/L) and can be used for PET imaging in ALI mice to alert early lung inflammation and to assess the efficacy of drug therapy. Our STING-targeted strategy also reveals that [18F]FBTA can trace ALI before reaching the computed tomography (CT) diagnostic criteria, and demonstrates its better specificity and distribution than [18F]fluorodeoxyglucose ([18F]FDG).

Research progress on stimulator of interferon genes (STING) agonists / 中国药科大学学报

@#Stimulator of interferon genes (STING) is an important factor in the auto-immune response of our bodies.Considering the mechanism of activating CD8+ T cells after the activation of STING protein, the combination of STING agonists and immune checkpoint inhibitors for the treatment of tumor immunotherapy has good clinical application prospect.In this paper, the research progress of molecular types, mechanism of action and structural modifications of STING agonists were reviewed.The developing tendency were outlined to provide some references for further investigation.

cGAS recognizes HTLV-1 RTI and induces STING-dependent innate immune responses / 中华微生物学和免疫学杂志

Objective To investigate whether cyclic GMP-AMP synthase ( cGAS ) , a cytosolic DNA sensor, could recognize the reverse transcription intermediate and induce the subsequent signaling path-way during the infection of human T cell leukemia virus type 1 ( HTLV-1 ) . Methods Biotin-labeled ssDNA90, a reverse transcription intermediate of HTLV-1, was transfected into HeLa cells and the interac-tion between it and cGAS was detected by co-immunoprecipitation experiments. HeLa cells were co-cultured with HTLV-1-positive MT2 cells and the interaction between cGAS and stimulator of interferon genes ( STING) was analyzed by co-immunoprecipitation experiments. The expression of STING in HeLa cells was silenced by siRNA. cGAS was transfected into the HeLa cells 24 h after the silencing and after 24 h, these cells were co-cultured with MT2 cells for another 24 h. Real-time PCR assay was used to measure the ex-pression of IFN-β, RANTES ( regulated upon activation, normal T-cell expressed, and secreted) , TNF-α, HTLV-1 protein Tax, p19 and HBZ. Immunoblot assay was performed to evaluate the phosphorylation of IRF3 and p65 in HeLa cells. Results cGAS interacted with ssDNA90. cGAS interacted with STING in the cytoplasm. In STING-silenced HeLa cells, cGAS transfection had no influence on the expression of IFN-β, RANTES , TNF-α, Tax , p19 or HBZ , nor did it affect the phosphorylation of IRF3 or p65 . Conclusions cGAS interacted with HTLV-1 RTI ssDNA90 and activated STING-dependent innate immune responses.

Research progress of cGAS-STING signaling pathway in anti-DNA virus immunity / 中国比较医学杂志

Innate immune system rapidly detects and responds to viruses at the early stage of viral infection. However,the mechanisms by which the immune system recognizes and eliminates them have not been fully clarified so far. Studies have shown that receptors are the primary tool for cell recognition and detection of viruses, and cyclic GMP-AMP synthase(cGAS)is one of the newly found DNA recognition receptors. cGAS transmits the signal to the downstream protein called STING(stimulator of interferon genes)and mediates the production of type I interferon(IFN-I),thereby to initiates the antiviral immunity of cells. This review briefly introduces the mechanism of the cGAS-STING signaling pathway, in order to provide a theoretical basis for the research and development of new antiviral drugs.