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Cyclic GMP-AMP synthase (cGAS), a key DNA sensor, detects cytosolic viral DNA and activates the adaptor protein stimulator of interferon genes (STING) to initiate interferon (IFN) production and host innate antiviral responses. Duck enteritis virus (DEV) is a duck alphaherpesvirus that causes an acute and contagious disease with high mortality in waterfowl. In the present study, we found that DEV inhibits host innate immune responses during the late phase of viral infection. Furthermore, we screened DEV proteins for their ability to inhibit the cGAS-STING DNA-sensing pathway and identified multiple viral proteins, including UL41, US3, UL28, UL53, and UL24, which block IFN-ß activation through this pathway. The DEV tegument protein UL41, which exhibited the strongest inhibitory effect, selectively downregulated the expression of interferon regulatory factor 7 (IRF7) by reducing its mRNA accumulation, thereby inhibiting the DNA-sensing pathway. Ectopic expression of UL41 markedly reduced viral DNA-triggered IFN-ß production and promoted viral replication, whereas deficiency of UL41 in the context of DEV infection increased the IFN-ß response to DEV and suppressed viral replication. In addition, ectopic expression of IRF7 inhibited the replication of the UL41-deficient virus, whereas IRF7 knockdown facilitated its replication. This study is the first report identifying multiple viral proteins encoded by a duck DNA virus, which inhibit the cGAS-STING DNA-sensing pathway. These findings expand our knowledge of DNA sensing in ducks and reveal a mechanism through which DEV antagonizes the host innate immune response. IMPORTANCE Duck enteritis virus (DEV) is a duck alphaherpesvirus that causes an acute and contagious disease with high mortality, resulting in substantial economic losses in the commercial waterfowl industry. The evasion of DNA-sensing pathway-mediated antiviral innate immunity is essential for the persistent infection and replication of many DNA viruses. However, the mechanisms used by DEV to modulate the DNA-sensing pathway remain poorly understood. In the present study, we found that DEV encodes multiple viral proteins to inhibit the cGAS-STING DNA-sensing pathway. The DEV tegument protein UL41 selectively diminished the accumulation of interferon regulatory factor 7 (IRF7) mRNA, thereby inhibiting the DNA-sensing pathway. Loss of UL41 potently enhanced the IFN-ß response to DEV and impaired viral replication in ducks. These findings provide insights into the host-virus interaction during DEV infection and help develop new live attenuated vaccines against DEV.
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Alphaherpesvirinae , Patos , Imunidade Inata , Nucleotidiltransferases , Proteínas Virais , Animais , DNA Viral/genética , DNA Viral/metabolismo , Enterite/imunologia , Enterite/virologia , Imunidade Inata/genética , Fator Regulador 7 de Interferon/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Evasão da Resposta Imune/genética , Alphaherpesvirinae/genética , Alphaherpesvirinae/imunologiaRESUMO
BACKGROUND: Activation of mTORC1 plays a significant role in cancer development and progression. However, the metabolic mechanisms to sustain mTORC1 activation of cancer cells within stressed environments are still under-appreciated. We recently revealed high autophagy activity in tumour cells with mTORC1 hyper-activation. Nevertheless, the functions and mechanisms of autophagy in regulating mTORC1 in glioma are not studied. METHODS: Using glioma patient database and human glioma cells, we assessed the mechanisms and function of selective autophagy to sustain mTORC1 hyper-activation in glioma. RESULTS: We revealed a strong association of altered mRNA levels in mTORC1 upstream and downstream genes with prognosis of glioma patients. Our results indicated that autophagy-mediated lipid catabolism was essential to sustain mTORC1 activity in glioma cells under energy stresses. We found that autophagy inhibitors or fatty acid oxidation (FAO) inhibitors in combination with 2-Deoxy-D-glucose (2DG) decreased energy production and survival of glioma cells in vitro. Consistently, inhibition of autophagy or FAO inhibitors with 2DG effectively suppressed the progression of xenografted glioma with hyper-activated mTORC1. CONCLUSIONS: This study established an autophagy/lipid degradation/FAO/ATP generation pathway, which might be used in brain cancer cells under energy stresses to maintain high mTORC1 signalling for tumour progression.
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Autofagia/fisiologia , Neoplasias Encefálicas/metabolismo , Metabolismo Energético/fisiologia , Glioma/metabolismo , Metabolismo dos Lipídeos , Animais , Apoptose/genética , Autofagia/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Metabolismo Energético/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Células HEK293 , Humanos , Metabolismo dos Lipídeos/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Nus , Transdução de Sinais/genéticaRESUMO
BACKGROUND: The internet has changed the way of people acquiring health information. Previous studies have shown that Wikipedia is a reasonably reliable medical resource, and it has been ranked higher than other general websites in various search engines. Baidu Encyclopedia is one of the most popular encyclopedia websites in China. However, no studies have shown the quality of the content provided in the Baidu Encyclopedia. OBJECTIVE: This study aimed to evaluate the quality of liver disease information provided by Wikipedia (in English) and Baidu Encyclopedia (in Chinese) and to perform a comparison of the quality and timeliness of the articles published in these two encyclopedias. Moreover, a 3-year follow-up study was conducted to compare if the information in both these websites was updated regularly over this period. METHODS: We searched for information on liver diseases by using the International Statistical Classification of Diseases and Related Health Problems 10th Revision Version 2016 codes on Wikipedia (in English) and Baidu Encyclopedia (in Chinese). The quality of the articles was assessed using the DISCERN instrument, which consists of 3 sections. We recorded the latest editing date of the webpages and calculated the date interval to evaluate the update timeliness of these websites. RESULTS: We found 22 entries on liver diseases in Baidu Encyclopedia and 15 articles in Wikipedia between September 15, 2016, and September 30, 2016, and we found 25 entries in Baidu Encyclopedia and 16 articles in Wikipedia between September 15, 2019, and September 30, 2019. In section 1 of the DISCERN instrument, the mean (SE) scores of Baidu Encyclopedia entries were significantly lower than those of Wikipedia articles. In section 2 and section 3 of the DISCERN instrument, the DISCERN scores of Baidu Encyclopedia entries were lower than those of Wikipedia articles, but the differences were not statistically significant. The total DISCERN scores of Baidu Encyclopedia entries were significantly lower than those of Wikipedia articles. The update interval of the entries in Baidu Encyclopedia was found to be significantly longer than that of the articles in Wikipedia. CONCLUSIONS: This study shows that the quality of articles and the reliability of the research content on liver diseases in Wikipedia are better than those of the entries in Baidu Encyclopedia. However, the quality of the treatment choices provided in both Wikipedia and Baidu Encyclopedia is not satisfactory. Wikipedia is updated more frequently than Baidu Encyclopedia, thereby ensuring that the information presented has the most recent research findings. The findings of our study suggest that in order to find accurate health information, it is important to seek the help of medical professionals instead of looking for a prescription amid the confusing information provided on the internet.
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Hepatopatias/epidemiologia , Humanos , Internet , Estudos Longitudinais , Ferramenta de BuscaRESUMO
Tuberous sclerosis complex (TSC) is a genetic disorder caused by inactivating mutations in TSC1 (hamartin) or TSC2 (tuberin), crucial negative regulators of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. TSC affects multiple organs including the brain. The neurologic manifestation is characterized by cortical tubers, subependymal nodules (SEN), and subependymal giant cell astrocytoma (SEGA) in brain. SEGAs may result in hydrocephalus in TSC patients and mTORC1 inhibitors are the current recommended therapy for SEGA. Nevertheless, a major limitation in the research for SEGA is the lack of cell lines or animal models for mechanistic investigations and development of novel therapy. In this study, we generated TSC1-deficient neural cells from spontaneously immortalized mouse astrocytes in an attempt to mimic human SEGA. The TSC1-deficient cells exhibit mTORC1 hyperactivation and characteristics of transition from astrocytes to neural stem/progenitor cell phenotypes. Rapamycin efficiently decreased mTORC1 activity of these TSC1-deficient cells in vitro. In vivo, TSC1-deficient cells could form SEGA-like tumors and Rapamycin treatment decreased tumor growth. Collectively, our study generates a novel SEGA-like cell line that is invaluable for studying mTORC1-driven molecular and pathological alterations in neurologic tissue. These SEGA-like cells also provide opportunities for the development of novel therapeutic strategy for TSC patients with SEGA.
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Astrocitoma/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Antibióticos Antineoplásicos/farmacologia , Astrócitos/metabolismo , Astrócitos/patologia , Astrocitoma/genética , Astrocitoma/patologia , Células Cultivadas , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Nus , Cultura Primária de Células/métodos , Sirolimo/farmacologia , Proteína 1 do Complexo Esclerose Tuberosa/deficiência , Proteína 1 do Complexo Esclerose Tuberosa/genéticaRESUMO
BACKGOUND: The mechanistic target of rapamycin complex 1 (mTORC1) is important in the development and progression of many cancers. Targeted cancer therapy using mTORC1 inhibitors is used for treatment of cancers; however, their clinical efficacies are still limited. METHODS: We recently created a new mouse model for human lymphangiosarcoma by deleting Tsc1 in endothelial cells and consequent hyper-activation of mTORC1. Using Tsc1iΔEC tumour cells from this mouse model, we assessed the efficacies of histone deacetylase (HDAC) inhibitors as anti-tumour agents for mTORC1-driven tumours. RESULTS: Unlike the cytostatic effect of mTORC1 inhibitors, HDAC inhibitors induced Tsc1iΔEC tumour cell death in vitro and their growth in vivo. Analysis of several HDAC inhibitors suggested stronger anti-tumour activity of class I HDAC inhibitor than class IIa or class IIb inhibitors, but these or pan HDAC inhibitor SAHA did not affect mTORC1 activation in these cells. Moreover, HDAC inhibitor-induced cell death required elevated autophagy, but was not affected by disrupting caspase-dependent apoptosis pathways. We also observed increased reactive oxygen species and endoplasmic reticulum stress in SAHA-treated tumour cells, suggesting their contribution to autophagic cell death, which were dependent on mTORC1 hyper-activation. CONCLUSION: These studies suggest a potential new treatment strategy for mTORC1-driven cancers like lymphangiosarcoma through an alternative mechanism.
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Antineoplásicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Linfangiossarcoma/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Terapia de Alvo Molecular/métodos , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Camundongos , Neoplasias Experimentais/patologiaRESUMO
BACKGROUND: Low resectability and poor survival outcome are common for hilar cholangiocarcinoma (HCCA), especially in advanced stages. The present study was to assess the clinical outcome of advanced HCCA, focusing on therapeutic modalities, survival analysis and prognostic assessment. METHODS: Clinical data of 176 advanced HCCA patients who had been treated in our hospital between January 2013 and December 2015 were analyzed retrospectively. Prognostic effects of clinicopathological factors were explored by univariate and multivariate analysis. Survival predictors were evaluated by the receiver operating characteristic (ROC) curve. RESULTS: The 3-year overall survival rate was 13% for patients with advanced HCCA. Preoperative total bilirubin (Pâ¯=â¯0.009), hepatic artery invasion (Pâ¯=â¯0.014) and treatment modalities (Pâ¯=â¯0.020) were independent prognostic factors on overall survival. A model combining these independent prognostic factors (area under ROC curve: 0.748; 95% CI: 0.678-0.811; sensitivity: 82.3%, specificity: 53.5%) was highly predictive of tumor death. After R0 resection, the 3-year overall survival was up to 38%. Preoperative total bilirubin was still an independent negative factor, but not for hepatic artery invasion. CONCLUSIONS: Surgery is still the best treatment for advanced HCCA. Preoperative biliary drainage should be performed in highly-jaundiced patients to improve survival. Prediction of survival is improved significantly by a model that incorporates preoperative total bilirubin, hepatic artery invasion and treatment modalities.
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Neoplasias dos Ductos Biliares/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar , Tumor de Klatskin/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Procedimentos Cirúrgicos do Sistema Biliar/mortalidade , Bilirrubina/sangue , Biomarcadores Tumorais/sangue , Distribuição de Qui-Quadrado , China , Colangiopancreatografia Retrógrada Endoscópica , Drenagem/instrumentação , Feminino , Artéria Hepática/patologia , Artéria Hepática/cirurgia , Humanos , Estimativa de Kaplan-Meier , Tumor de Klatskin/sangue , Tumor de Klatskin/mortalidade , Tumor de Klatskin/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
PREMISE OF STUDY: Leaf area and dry mass are crucial for plant metabolic performance. The "diminishing returns" hypothesis predicts that leaf area will scale less than one with respect to leaf dry mass, indicating that the cost of light interception increases with leaf area. However, it remains unclear whether and how this scaling relationship varies among species growing in different environments. METHODS: More than 2000 measurements from five bamboo species adapted to high and low light and growing at different elevations in Wuyi Mountains, Southeast China, were used to explore how the leaf area vs. dry mass scaling relationship was affected by light and elevation. KEY RESULTS: The data indicate that (1) the normalization constants for leaf area vs. dry mass were positively but not significantly correlated with increasing leaf size and that (2) the scaling exponents remained numerically invariant among all five bamboo species, with a common slope of 0.85. Standardized major axis (SMA) analyses and comparisons of 95% confidence intervals also showed that the numerical values of the scaling exponents did not differ regardless of elevation and were similar between shaded and unshaded adapted species, whereas the numerical values of the normalization constants increased with decreasing light. CONCLUSIONS: The data collected for all five bamboo species are consistent with the "diminishing returns" hypothesis, i.e., the scaling exponents governing the leaf area vs. dry mass scaling relationship are less than one within and across species and are insensitive to light conditions or elevation.
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Altitude , Luz , Folhas de Planta/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , ChinaRESUMO
OBJECTIVE: This case-control study is designed to explore the relationship between microRNA-196a2 (MIR196A2) rs11614913 C > T polymorphism and the risk of hepatopulmonary syndrome (HPS) in liver cirrhosis. METHODS: From January 2013 to January 2015, 163 liver cirrhosis patients with HPS (case group), 264 liver cirrhosis patients without HPS (control group), and 195 healthy people (normal group) were selected. A DNA extraction kit was used to extract plasma DNA from peripheral blood. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the allele and genotype frequencies of MIR196A2 C > T polymorphism. Real-time quantitative polymerase chain reaction was adopted to detect the relative expression of MIR196A. RESULTS: The frequencies of C allele in the case group were higher than those in the control and normal groups (all P < 0.05), whereas no significant difference was found between the control and normal groups, which indicated that MIR196A2 C > T polymorphism was closely associated with an increased risk of HPS in patients with liver cirrhosis. Compared with the normal group, the relative expression of MIR196A in the case group was significantly increased (P < 0.05), but there was no significant difference in the control group (P > 0.05). In the case group, compared with patients carrying the TT genotype, the relative expression of MIR196A of patients carrying the C allele (CT + CC) evidently increased (P < 0.05). CONCLUSIONS: The MIR196A2 rs11614913 C > T polymorphism may contribute to an increased risk of HPS in liver cirrhosis patients.
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Cholesterol catabolism by actinobacteria has been extensively studied. In contrast, the uptake and catabolism of cholesterol by Gram-negative species are poorly understood. Here, we investigated microbial cholesterol catabolism at the subcellular level. (13)C metabolomic analysis revealed that anaerobically grown Sterolibacterium denitrificans, a ß-proteobacterium, adopts an oxygenase-independent pathway to degrade cholesterol. S. denitrificans cells did not produce biosurfactants upon growth on cholesterol and exhibited high cell surface hydrophobicity. Moreover, S. denitrificans did not produce extracellular catabolic enzymes to transform cholesterol. Accordingly, S. denitrificans accessed cholesterol by direction adhesion. Cholesterol is imported through the outer membrane via a putative FadL-like transport system, which is induced by neutral sterols. The outer membrane steroid transporter is able to selectively import various C27 sterols into the periplasm. S. denitrificans spheroplasts exhibited a significantly higher efficiency in cholest-4-en-3-one-26-oic acid uptake than in cholesterol uptake. We separated S. denitrificans proteins into four fractions, namely the outer membrane, periplasm, inner membrane, and cytoplasm, and we observed the individual catabolic reactions within them. Our data indicated that, in the periplasm, various periplasmic and peripheral membrane enzymes transform cholesterol into cholest-4-en-3-one-26-oic acid. The C27 acidic steroid is then transported into the cytoplasm, in which side-chain degradation and the subsequent sterane cleavage occur. This study sheds light into microbial cholesterol metabolism under anoxic conditions.
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Hipóxia Celular , Colesterol/metabolismo , Bactérias Gram-Negativas/metabolismo , Esteróis/metabolismo , Anaerobiose , Radioisótopos de Carbono/química , Colestenonas/química , Colestenonas/metabolismo , Colesterol/química , Bactérias Gram-Negativas/química , Lipólise , Metabolismo/genética , Oxirredução , Periplasma/enzimologia , Rhodocyclaceae/enzimologia , Esteróis/química , Especificidade por SubstratoRESUMO
BACKGROUND: Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities. According to previous literature, the most commonly involved sports are soccer, sprinting, and gymnastics, in descending order. Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare. CASE SUMMARY: A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip. She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior. Eventually, she underwent surgery and obtained satisfactory treatment results. CONCLUSION: Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery. For old fractures with nonunion and chronic buttock pain, surgery is a preferred therapeutic choice with good treatment outcomes.
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Most breast cancers do not respond to immune checkpoint inhibitors and there is an urgent need to identify novel sensitization strategies. Herein, we uncovered that activation of the TBK-IFN pathway that is mediated by the TBK1 adapter protein AZI2 is a potent strategy for this purpose. Our initial observations showed that RB1CC1 depletion leads to accumulation of AZI2, in puncta along with selective macroautophagy/autophagy cargo receptors, which are both required for TBK1 activation. Specifically, disrupting the selective autophagy function of RB1CC1 was sufficient to sustain AZI2 puncta accumulation and TBK1 activation. AZI2 then mediates downstream activation of DDX3X, increasing its interaction with IRF3 for transcription of pro-inflammatory chemokines. Consequently, we performed a screen to identify inhibitors that can induce the AZI2-TBK1 pathway, and this revealed Lys05 as a pharmacological agent that induced pro-inflammatory chemokine expression and CD8+ T cell infiltration into tumors. Overall, we have identified a distinct AZI2-TBK1-IFN signaling pathway that is responsive to selective autophagy blockade and can be activated to make breast cancers more immunogenic.Abbreviations: AZI2/NAP1: 5-azacytidine induced 2; CALCOCO2: calcium binding and coiled-coil domain 2; DDX3X: DEAD-box helicase 3 X-linked; FCCP: carbonyl cyanide p-triflouromethoxyphenylhydrazone; a protonophore that depolarizes the mitochondrial inner membrane; ICI: immune checkpoint inhibitor; IFN: interferon; NBR1: NBR1 autophagy cargo receptor; OPTN: optineurin; RB1CC1/FIP200: RB1 inducible coiled-coil 1; SQSTM1/p62: sequestosome 1; TAX1BP1: Tax1 binding protein 1; TBK1: TANK binding kinase 1.
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Neoplasias da Mama , Macroautofagia , Humanos , Feminino , Autofagia , Linfócitos T CD8-Positivos , Linfócitos T , Proteínas Serina-Treonina QuinasesRESUMO
The GTP-binding protein Rac regulates diverse cellular functions including activation of NADPH oxidase, a major source of superoxide production (O(2)(·-)). Rac1-mediated NADPH oxidase activation is increased after myocardial infarction (MI) and heart failure both in animals and humans; however, the impact of increased myocardial Rac on impending ischemia-reperfusion (I/R) is unknown. A novel transgenic mouse model with cardiac-specific overexpression of constitutively active mutant form of Zea maize Rac D (ZmRacD) gene has been reported with increased myocardial Rac-GTPase activity and O(2)(·-) generation. The goal of the present study was to determine signaling pathways related to increased myocardial ZmRacD and to what extent hearts with increased ZmRacD proteins are susceptible to I/R injury. The effect of myocardial I/R was examined in young adult wild-type (WT) and ZmRacD transgenic (TG) mice. In vitro reversible myocardial I/R for postischemic cardiac function and in vivo regional myocardial I/R for MI were performed. Following 20-min global ischemia and 45-min reperfusion, postischemic cardiac contractile function and heart rate were significantly reduced in TG hearts compared with WT hearts. Importantly, acute regional myocardial I/R (30-min ischemia and 24-h reperfusion) caused significantly larger MI in TG mice compared with WT mice. Western blot analysis of cardiac homogenates revealed that increased myocardial ZmRacD gene expression is associated with concomitant increased levels of NADPH oxidase subunit gp91(phox), O(2)(·-), and P(21)-activated kinase. Thus these findings provide direct evidence that increased levels of active myocardial Rac renders the heart susceptible to increased postischemic contractile dysfunction and MI following acute I/R.
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Traumatismo por Reperfusão Miocárdica/enzimologia , Miocárdio Atordoado/enzimologia , Miócitos Cardíacos/enzimologia , Proteínas rac de Ligação ao GTP/metabolismo , Animais , Western Blotting , Modelos Animais de Doenças , Genótipo , Frequência Cardíaca , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Contração Miocárdica , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio Atordoado/genética , Miocárdio Atordoado/patologia , Miocárdio Atordoado/fisiopatologia , Miócitos Cardíacos/patologia , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , Fenótipo , Transdução de Sinais , Superóxidos/metabolismo , Fatores de Tempo , Regulação para Cima , Quinases Ativadas por p21/metabolismo , Proteínas rac de Ligação ao GTP/genéticaRESUMO
Lymphatic malformation (LM) is a vascular anomaly from lymphatic endothelial cells (ECs), and a fraction of the patients could progress to the deadly malignant lymphangiosarcoma (LAS). Using genetic tools to delete an essential autophagy gene Rb1cc1/FIP200 or its mutation specifically blocking its autophagy function, we demonstrated that autophagy inhibition abrogated LM progression to LAS although not affecting LM formation in our recently developed mouse model of LAS. Analysis of the mouse models in vivo and vascular tumor cells in vitro showed that autophagy inhibition reduced vascular tumor cell proliferation in vitro and tumorigenicity in vivo without affecting mTORC1 signaling as an oncogenic driver directly. Transcriptional profiling of autophagy-deficient tumor cells and further mechanistic studies revealed a role for osteopontin (OPN) and its downstream Jak/Stat3 signaling in mediating regulation of vascular tumor cells by autophagy. Together, these results support potential new prophylactic strategies to targeting autophagy and/or its downstream OPN expression to prevent progression of the benign LM to the malignant and deadly LAS.Abbreviations: LM: lymphatic malformation; EC: endothelial cell; LAS: lymphangiosarcoma; OPN: osteopontin; RB1CC1: RB1 Inducible Coiled-Coil 1; FIP200: FAK family-interacting protein of 200 kDa.
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This paper is concerned with the adaptive tracking control problem for nonlinear systems with virtual control coefficients including known and unknown items. The known items are employed for controller design directly, such that more information is utilized to achieve better performance. To deal with the unknown items, a novel real control law is firstly constructed by introducing an auxiliary system. The proposed controller is designed and applied to an uncertain TCP/AQM network system, which guarantees the practical boundedness of all the signals in the closed-loop system. Finally, the effectiveness and practicability of the developed control strategy are validated by simulation results.
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Lymphatic malformation (LM) is a vascular anomaly originating from lymphatic endothelial cells (ECs). While it mostly remains a benign disease, a fraction of LM patients progresses to malignant lymphangiosarcoma (LAS). However, very little is known about underlying mechanisms regulating LM malignant transformation to LAS. Here, we investigate the role of autophagy in LAS development by generating EC-specific conditional knockout of an essential autophagy gene Rb1cc1/FIP200 in Tsc1iΔEC mouse model for human LAS. We find that Fip200 deletion blocked LM progression to LAS without affecting LM development. We further show that inhibiting autophagy by genetical ablation of FIP200, Atg5 or Atg7, significantly inhibited LAS tumor cell proliferation in vitro and tumorigenicity in vivo. Transcriptional profiling of autophagy-deficient tumor cells and additional mechanistic analysis determine that autophagy plays a role in regulating Osteopontin expression and its down-stream Jak/Stat3 signaling in tumor cell proliferation and tumorigenicity. Lastly, we show that specifically disrupting FIP200 canonical autophagy function by knocking-in FIP200-4A mutant allele in Tsc1iΔEC mice blocked LM progression to LAS. These results demonstrate a role for autophagy in LAS development, suggesting new strategies for preventing and treating LAS.
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Linfangiossarcoma , Humanos , Camundongos , Animais , Proteínas Relacionadas à Autofagia , Células Endoteliais , Osteopontina , Autofagia/genética , Fator de Transcrição STAT3RESUMO
RB1CC1/FIP200 is an essential macroautophagy/autophagy protein that plays an important role in a variety of biological and disease processes through its canonical autophagy-dependent and -independent functions. However, it remains largely unknown whether post-translational modifications could regulate RB1CC1 and its associated autophagy functions. Here, we report acetylation of several lysine residues of RB1CC1 by acetyltransferase CREBBP (CREB binding protein), with K276 as the major CREBBP acetylation site. K276 is also identified as a ubiquitination site by mass spectrometry, and acetylation at this site reduces ubiquitination of RB1CC1 to inhibit its ubiquitin-dependent degradation. We also find that RB1CC1 contains an N-terminal intrinsically disordered region (IDR) capable of forming liquid-liquid phase separation (LLPS) in vitro, which may drive formation of RB1CC1 puncta with LLPS properties in cells independent of SQSTM1/p62 and other autophagy receptors CALCOCO2/NDP52, NBR1, TAX1BP1 and OPTN. Mutational analysis shows that both K276 acetylation and the N-terminal IDR containing it are important for maintaining canonical autophagy function of RB1CC1 in breast cancer cells. Our findings demonstrate regulation of RB1CC1 by a new post-translational mechanism and suggest potential therapeutic application of inducing RB1CC1 degradation through blocking K276 acetylation in the treatment of cancer and other diseases.Abbreviations: Baf-A1: bafilomycin A1; CREBBP/CBP: CREB binding protein; CHX: cycloheximide; EP300/p300: E1A binding protein p300; FRAP: fluorescence recovery after photobleaching; HADCs: histone deacetylases; IDR: intrinsically disordered region; LLPS: liquid-liquid phase separation; KAT2A/GCN5: lysine acetyltransferase 2A; KAT2B/PCAF: lysine acetyltransferase 2B; KAT5/TIP60: lysine acetyltransferase 5; KAT8/MOF: lysine acetyltransferase 8; NAM: nicotinamide; PAS: phagophore assembly site; PEG-8000: polyethylene glycol 8000; RB1CC1/FIP200: RB1 inducible coiled-coil 1; TSA: trichostatin A.
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Autofagia , Proteína de Ligação a CREB , Acetilação , Processamento de Proteína Pós-Traducional , Proteínas de Ciclo CelularRESUMO
Although recruiting T cells to convert cold tumors into hot can prevent some tumors from evading immune surveillance, tumors have evolved more mechanisms to achieve immune evasion, such as downregulating major histocompatibility complex I (MHC I) molecules expression to prevent T cells from recognizing tumor-antigens, or secreting immune suppression cytokines that disable T cells. Tumor immune evasion not only promotes tumor growth, but also weakens the efficacy of existing tumor immunotherapies. Therefore, recruiting T cells while reshaping innate immunity plays an important role in preventing tumor immune escape. In this study, we constructed a long-acting in situ forming implant (ISFI) based on the Atrigel technology, co-encapsulated with G3-C12 and sulfisoxazole (SFX) as a drug depot in the tumor site (SFX + G3-C12-ISFI). First, G3-C12 could recruit T cells, and transform cold into hot tumors. Furthermore, SFX could inhibit tumor-derived exosomes secretion, reduce the shedding of NKG2D ligand (NKG2DL), repair NKG2D/NKG2DL pathway, reinvigorate natural killer (NK) cells, and evade the effects of MHC I molecules missing. In the humanized cold tumor model, our strategy showed an excellent anti-tumor effect, providing a smart strategy for solving tumor evasion immune surveillance.
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Neoplasias , Linfócitos T , Humanos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais , Neoplasias/metabolismo , Imunidade InataRESUMO
When it comes to long-acting injections, lyotropic liquid crystals (LLCs) are considered as an effective and powerful drug delivery technology due to their low manufacturing and injection difficulty, consistent releasing behaviors with low burst, as well as broadly applicable drug loading capacity. However, monoolein and phytantriol, as two widely used LLC-forming materials, may give rise to tissue cytotoxicity and undesired immunological responses, which may hinder the wide application of this technology. In this study, we opted for two ingredients, phosphatidylcholine and α-tocopherol, as carriers on account of their nature-obtainable and biocompatible qualities. By changing the ratios between them, we conducted research on crystalline types, nanosized structures, viscoelastic differences, characteristics of releasing behaviors, and in vivo safety. To fully exploit this in situ LLC platform with both injectability and sprayability, we focused on the treatment of both hormone-sensitive (HSPC) and castration-resistant prostate cancer (CRPC). For HSPC, we found that spraying leuprolide and a cabazitaxel-loaded LLC platform on the tumor bed after resection greatly reduced tumor metastatic rate and prolonged the survival time. Besides, for CRPC, our results demonstrated that although leuprolide (a kind of drug for castration) alone could hardly limit the progression of CRPC with low MHC-I expression, its combination with cabazitaxel in our LLC platform achieved a significantly better tumor-inhibiting and anti-recurrent efficacy than single cabazitaxel-loaded LLC platform, owing to enhanced CD4+ T cell infiltration in tumors and immune-potentiating cytokines. In conclusion, our dual-functional and clinically achievable strategy might provide a treating solution toward both HSPC and CRPC.
Assuntos
Cristais Líquidos , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Leuprolida/uso terapêutico , Taxoides/uso terapêuticoRESUMO
Macrophages are central to the pathogenesis of kidney disease and serve as an effective therapeutic target for kidney injury and fibrosis. Among them, M2-type macrophages have double-edged effects regarding anti-inflammatory effects and tissue repair. Depending on the polarization of the M2 subtypes (M2a or M2c) in the diseased microenvironment, they can either mediate normal tissue repair or drive tissue fibrosis. In renal fibrosis, M2a promotes disease progression through macrophage-to-myofibroblast transition (MMT) cells, while M2c possesses potent anti-inflammatory functions and promotes tissue repair, and is inhibited. The mechanisms underlying this differentiation are complex and are currently not well understood. Therefore, in this study, we first confirmed that M2a-derived MMT cells are responsible for the development of renal fibrosis and demonstrated that the intensity of TGF-ß signaling is a major factor determining the differential polarization of M2a and M2c. Under excessive TGF-ß stimulation, M2a undergoes a process known as MMT cells, whereas moderate TGF-ß stimulation favors the polarization of M2c phenotype macrophages. Based on these findings, we employed targeted nanotechnology to codeliver endoplasmic reticulum stress (ERS) inhibitor (Ceapin 7, Cea or C) and conventional glucocorticoids (Dexamethasone, Dex or D), precisely modulating the ATF6/TGF-ß/Smad3 signaling axis within macrophages. This approach calibrated the level of TGF-ß stimulation on macrophages, promoting their polarization toward the M2c phenotype and suppressing excessive MMT polarization. The study indicates that the combination of ERS inhibitor and a first-line anti-inflammatory drug holds promise as an effective therapeutic approach for renal fibrosis resolution.
Assuntos
Nefropatias , Humanos , Nefropatias/patologia , Macrófagos , Fator de Crescimento Transformador beta/farmacologia , Fibrose , Anti-Inflamatórios/farmacologiaRESUMO
It has been known that Rho-associated protein kinase (ROCK) signaling regulates the migration of vascular smooth muscle cells (VSMCs). However, the isoform-specific roles of ROCK and its underlying mechanism in VSMC migration are not well understood. The current study thus aimed to investigate the roles of ROCK1/2 and their relationship to the MAPK signaling pathway in platelet-derived growth factor (PDGF)-induced rat aorta VSMC migration by manipulating ROCK gene expression. The results revealed that ROCK1 small interfering ribonucleic acid (siRNA) rather than ROCK2 siRNA decreased PDGF-BB-generated VSMC migration, and upregulation of ROCK1 expression via transfection of constructed pEGFP-C1/ROCK1 plasmid further increased the migration of PDGF-BB-treated VSMCs. In PDGF-treated VSMCs, ROCK1 siRNA did not affect the phosphorylation levels of ERK and p38 in the cytoplasm, but decreased the level of ERK phosphorylation in the nucleus. These findings demonstrate that activated ROCK1 can promote VSMC migration through facilitating phosphorylation and nuclear translocation of ERK protein.