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Specific heat capacity is one of the most fundamental thermodynamic properties of materials. In this work, we measured the specific heat capacity of PbSe nanocrystals with diameters ranging from 5 to 23 nm, and its value increases significantly from 0.2 to 0.6 J g-1 °C-1. We propose a mass assignment model to describe the specific heat capacity of nanocrystals, which divides it into four parts: electron, inner, surface, and ligand. By eliminating the contribution of ligand and electron specific heat capacity, the specific heat capacity of the inorganic core is linearly proportional to its surface-to-volume ratio, showing the size dependence. Based on this linear relationship, surface specific heat capacity accounts for 40-60% of the specific heat capacity of nanocrystals with size decreasing. It can be attributed to the uncoordinated surface atoms, which is evidenced by the appearance of extra surface phonons in Raman spectra and ab initio molecular dynamics (AIMD) simulations.
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Cancer cells, including those of prostate cancer (PCa), often hijack intrinsic cell signaling to reprogram their metabolism. Part of this reprogramming includes the activation of de novo synthesis of fatty acids that not only serve as building blocks for membrane synthesis but also as energy sources for cell proliferation. However, how de novo fatty acid synthesis contributes to PCa progression is still poorly understood. Herein, by mining public datasets, we discovered that the expression of acetyl-CoA carboxylase alpha (ACACA), which encodes acetyl-CoA carboxylase 1 (ACC1), was highly expressed in human PCa. In addition, patients with high ACACA expression had a short disease-free survival time. We also reported that depletion of ACACA reduced de novo fatty acid synthesis and PI3K/AKT signaling in the human castration-resistant PCa (CRPC) cell lines DU145 and PC3. Furthermore, depletion of ACACA downregulates mitochondrial beta-oxidation, resulting in mitochondrial dysfunction, a reduction in ATP production, an imbalanced NADP+/NADPhydrogen(H) ratio, increased reactive oxygen species, and therefore apoptosis. Reduced exogenous fatty acids by depleting lipid or lowering serum supplementation exacerbated both shRNA depletion and pharmacological inhibition of ACACA-induced apoptosis in vitro. Collectively, our results suggest that inhibition of ectopic ACACA, together with suppression of exogenous fatty acid uptake, can be a novel strategy for treating currently incurable CRPC.
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Acetil-CoA Carboxilasa , Ácidos Grasos , Mitocondrias , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Acetil-CoA Carboxilasa/metabolismo , Ácidos Grasos/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Línea Celular TumoralRESUMEN
Stimulatorof interferon genes (STING) is an intracellular sensor of cyclic dinucleotides involved in the innate immune response against pathogen- or self-derived DNA. For years, interferon (IFN) induction of cyclic GMP-AMP synthase (cGAS)-STING has been considered as a canonical pattern defending the host from viral invasion. The mechanism of the cGAS-STING-IFN pathway has been well-illustrated. However, other signalling cascades driven by cGAS-STING have emerged in recent years and some of them have been found to possess antiviral ability independent of IFN. Here, we summarize the current progress on cGAS-STING-mediated nonclassic antiviral activities with an emphasis on the nuclear factor-κB and autophagy pathways, which are the most-studied pathways. In addition, we briefly present the primordial function of the cGAS-STING pathway in primitive species to show the importance of IFN-unrelated antiviral activity from an evolutionary angle. Finally, we discuss open questions that need to be solved for further exploitation of this field.
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Inmunidad Innata , Nucleotidiltransferasas , Humanos , Nucleotidiltransferasas/genética , Transducción de Señal , Interferones , Antivirales/farmacologíaRESUMEN
Coronaviruses employ various strategies for survival, among which the activation of endogenous or exogenous apoptosis stands out, with viral proteins playing a pivotal role. Notably, highly pathogenic coronaviruses such as SARS-CoV-2, SARS-CoV, and MERS-CoV exhibit a greater array of non-structural proteins compared to low-pathogenic strains, facilitating their ability to induce apoptosis via multiple pathways. Moreover, these viral proteins are adept at dampening host immune responses, thereby bolstering viral replication and persistence. This review delves into the intricate interplay between highly pathogenic coronaviruses and apoptosis, systematically elucidating the molecular mechanisms underpinning apoptosis induction by viral proteins. Furthermore, it explores the potential therapeutic avenues stemming from apoptosis inhibition as antiviral agents and the utilization of apoptosis-inducing viral proteins as therapeutic modalities. These insights not only shed light on viral pathogenesis but also offer novel perspectives for cancer therapy.
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Apoptosis , SARS-CoV-2 , Humanos , SARS-CoV-2/fisiología , Proteínas Virales/metabolismo , Proteínas Virales/genética , Coronavirus del Síndrome Respiratorio de Oriente Medio/fisiología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , COVID-19/virologíaRESUMEN
Recognizing aberrant cytoplasmic double-stranded DNA and stimulating innate immunity is essential for the host's defense against viruses and tumors. Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a cytosolic DNA sensor that synthesizes the second messenger 2'3'-cGAMP and subsequently activates stimulator of interferon genes (STING)-mediated activation of TANK-binding kinase 1 (TBK1)/interferon regulatory factor 3 (IRF3) and the production of type I interferon (IFN-I). Both the cGAS-STING-mediated IFN-I antiviral defense and the countermeasures developed by diverse viruses have been extensively studied. However, recent studies have revealed a convergent evolutionary feature of severe acute respiratory syndrome coronavirus 2 and human immunodeficiency virus (HIV) viral proteins in terms of the selective regulation of cGAS-STING-mediated nuclear factor-κB (NF-κB) signaling without any effect on cGAS-STING-mediated TBK1/IRF3 activation and IFN production. The potential beneficial effect of this cGAS-STING-mediated, NF-κB-dependent antiviral effect, and the possible detrimental effect of IFN-I in the pathogenesis of coronavirus disease 2019 and HIV infection deserve more attention and future investigation.
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COVID-19 , Infecciones por VIH , Infecciones por Papillomavirus , Humanos , SARS-CoV-2/genética , FN-kappa B/metabolismo , Nucleotidiltransferasas , Inmunidad Innata , ADN/metabolismo , AntiviralesRESUMEN
Recognizing aberrant cytoplasmic dsDNA and stimulating cGAS-STING-mediated innate immunity is essential for the host defense against viruses. Recent studies have reported that SARS-CoV-2 infection, responsible for the COVID-19 pandemic, triggers cGAS-STING activation. cGAS-STING activation can trigger IRF3-Type I interferon (IFN) and autophagy-mediated antiviral activity. Although viral evasion of STING-triggered IFN-mediated antiviral function has been well studied, studies concerning viral evasion of STING-triggered autophagy-mediated antiviral function are scarce. In the present study, we have discovered that SARS-CoV-2 ORF3a is a unique viral protein that can interact with STING and disrupt the STING-LC3 interaction, thus blocking cGAS-STING-induced autophagy but not IRF3-Type I IFN induction. This novel function of ORF3a, distinct from targeting autophagosome-lysosome fusion, is a selective inhibition of STING-triggered autophagy to facilitate viral replication. We have also found that activation of bat STING can induce autophagy and antiviral activity despite its defect in IFN induction. Furthermore, ORF3a from bat coronaviruses can block bat STING-triggered autophagy and antiviral function. Interestingly, the ability to inhibit STING-induced autophagy appears to be an acquired function of SARS-CoV-2 ORF3a, since SARS-CoV ORF3a lacks this function. Taken together, these discoveries identify ORF3a as a potential target for intervention against COVID-19.
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COVID-19 , Quirópteros , Interferón Tipo I , Animales , Humanos , Antivirales , Autofagia , Inmunidad Innata , Proteínas de la Membrana/genética , Nucleotidiltransferasas , Pandemias , SARS-CoV-2/metabolismoRESUMEN
Cellular infections by DNA viruses trigger innate immune responses mediated by DNA sensors. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) signaling pathway has been identified as a DNA-sensing pathway that activates interferons in response to viral infection and, thus, mediates host defense against viruses. Previous studies have identified oncogenes E7 and E1A of the DNA tumor viruses, human papillomavirus 18 (HPV18) and adenovirus, respectively, as inhibitors of the cGAS-STING pathway. However, the function of STING in infected cells and the mechanism by which HPV18 E7 antagonizes STING-induced Interferon beta production remain unknown. We report that HPV18 E7 selectively antagonizes STING-triggered nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation but not IRF3 activation. HPV18 E7 binds to STING in a region critical for NF-κB activation and blocks the nuclear accumulation of p65. Moreover, E7 inhibition of STING-triggered NF-κB activation is related to HPV pathogenicity but not E7-Rb binding. HPV18 E7, severe acute respiratory syndrome coronavirus-2 open reading frame 3a, human immunodeficiency virus-2 viral protein X, and Kaposi's sarcoma-associated herpesvirus KSHV viral interferon regulatory factor 1 selectively inhibited STING-triggered NF-κB or IRF3 activation, suggesting a convergent evolution among these viruses toward antagonizing host innate immunity. Collectively, selective suppression of the cGAS-STING pathway by viral proteins is likely to be a key pathogenic determinant, making it a promising target for treating oncogenic virus-induced tumor diseases.
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COVID-19 , FN-kappa B , Humanos , FN-kappa B/metabolismo , Interferón beta/genética , Papillomavirus Humano 18/genética , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Inmunidad Innata , ADN , Virus ADN/genética , Virus ADN/metabolismo , Proteínas OncogénicasRESUMEN
To comprehensively evaluate the quality of commercial Ginseng Radix et Rhizoma Rubra, 43 batches of commercial Ginseng Radix et Rhizoma Rubra were collected to determine the content of nine ginsenosides Rg_1, Re, Rb_1, Rk_3, Rh_4, 20(S)-Rg_3, 20(R)-Rg_3, Rk_1, and Rg_5 by high performance liquid chromatography(HPLC). The quality of the commercial Ginseng Radix et Rhizoma Rubra was evaluated by correlation analysis, principal component analysis, factor analysis, analysis of variance(ANOVA), and cluster heatmap analysis. The content determination indicated that the content of common ginsenosides in commercial Ginseng Radix et Rhizoma Rubra were higher while that of rare ginsenosides were lower. Multivariate statistical analysis revealed that ginsenosides Rg_1 and Rb_1 were significantly positively correlated with rare ginsenosides, and Rg_1, Rb_1 and rare ginsenosides played an important role in evaluating the quality of commercial Ginseng Radix et Rhizoma Rubra. In combination with the processing principle and current quality situation of Ginseng Radix et Rhizoma Rubra, it is recommended to improve the content limit of Rb_1 in the existing quality standards.
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Medicamentos Herbarios Chinos , Ginsenósidos , Panax , Ginsenósidos/análisis , Rizoma/química , Raíces de Plantas/química , Cromatografía Líquida de Alta PresiónRESUMEN
BACKGROUND: Growing evidence demonstrated that dietary protein intake may be a risk factor for prostate cancer and elevate the level of prostate-specific antigen (PSA). However, proof for the correlation between dietary protein intake and PSA in American adults without prostate tumor history is limited. Our goal was to investigate the association of dietary protein intake with PSA using the National Health and Nutrition Examination Survey (NHANES) (2003-2010) database. METHODS: After the screening, 6403 participants were included in the study. The interested independent is the dietary protein intake, and the dependent variable is PSA levels, the covariates included demographic, dietary, biological data, and physical examination variables. A weighted linear model and a weighted linear regression model were used to examine the distribution of variables in the covariate differences between the different independent groups according to quartiles. Four models were used to survey the association between dietary protein intake and PSA. We also attempted to find a nonlinear relationship between dietary protein intake and PSA using the GAM model and the penalty spline method and further solved the nonlinear problem using weighted two-piecewise linear model. RESULTS: The weighted multivariate linear regression analysis demonstrated that dietary protein intake was not independently associated with PSA levels after adjusting potential confounders (ß = 0.015, 95%CI:-0.024, 0.055). However, we found the non-linear relationship between dietary protein intake and PSA, whose point was 18.18 g (per 10 g change). The magnitude and confidence intervals for the left and right inflection points are - 0.03 (- 0.09, 0.02) and 0.22 (0.07, 0.36), respectively. On the right side of the inflection point, one gram of increment in protein intake was associated with increased PSA levels by 0.22 (log2 transformation: 0.22, 95%CI: 0.07, 0.36). CONCLUSIONS: After adjusting for potential covariates, the non-linear correlation between dietary protein intake and PSA was observed. When dietary protein intake exceeded the threshold of 181.8 g, dietary protein intake was positively correlated with elevated PSA levels.
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Proteínas en la Dieta/administración & dosificación , Calicreínas/sangre , Encuestas Nutricionales/estadística & datos numéricos , Antígeno Prostático Específico/sangre , Próstata/efectos de los fármacos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/epidemiología , Adulto , Anciano , Biomarcadores/sangre , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estado Nutricional/fisiología , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/etiología , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND AND OBJECTIVES: Previous study has reported phosphorus intake is associated prostate cancer (PCa), but the association between phosphorus intake and serum prostate specific antigen (PSA) levels hasn't been reported in non-history of PCa population. Therefore, we performed a secondary data analysis based on existing data from the public Nutrition Examination Survey (NHANES) (2003-2010) database. METHODS AND STUDY DESIGN: Totally 6403 participants were selected from NHANES (2003-2010) database. The interested independent and dependent variables were considered as dietary phosphorus intake and PSA level, respectively. Covariates included demographic data, dietary data, physical examination data, and comorbidities. Weighted linear regression and generalized additive models were used to addressing the linear and non-linear link of phosphorus intake to PSA level. RESULTS: Linear association between phosphorus intake and PSA was not detected [ß=0.016 (95% Confidence Interval (CI) -0.012, 0.045)]. But we found an existing nonlinearity. By the recursive algorithm, the inflection point was 1151 mg. On the left side of the inflection point, we did not find the correlation between dietary phosphorus intake (per 100 change) and PSA level [ß=-0.04 (95% CI -0.11, 0.02), p=0.2155], while dietary phosphorus intake (per 100 change) positively associated with PSA [ß=0.05 (95% CI 0.01, 0.09) p=0.0293] on the right side of inflection point. CONCLUSIONS: There is a non-linear correlation between dietary phosphorus intake and PSA. Dietary phosphorus intake was positively associated with increased PSA when dietary phosphorus intake is beyond 1151 mg after adjusting other covariates. Over 1151 mg per day dietary phosphorus intake may be the risk factor for PSA increasing.
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Fósforo Dietético , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/epidemiología , Humanos , Masculino , Encuestas Nutricionales , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/etiología , Estados Unidos/epidemiologíaRESUMEN
There is growing evidence that alternative splicing (AS) plays an important role in cancer development. However, a comprehensive analysis of AS signatures in kidney renal clear cell carcinoma (KIRC) is lacking and urgently needed. It remains unclear whether AS acts as diagnostic biomarkers in predicting the prognosis of KIRC patients. In the work, gene expression and clinical data of KIRC were obtained from The Cancer Genome Atlas (TCGA), and profiles of AS events were downloaded from the SpliceSeq database. The RNA sequence/AS data and clinical information were integrated, and we conducted the Cox regression analysis to screen survival-related AS events and messenger RNAs (mRNAs). Correlation between prognostic AS events and gene expression were analyzed using the Pearson correlation coefficient. Protein-protein interaction analysis was conducted for the prognostic AS-related genes, and a potential regulatory network was built using Cytoscape (version 3.6.1). Meanwhile, functional enrichment analysis was conducted. A prognostic risk score model is then established based on seven hub genes (KRT222, LENG8, APOB, SLC3A1, SCD5, AQP1, and ADRA1A) that have high performance in the risk classification of KIRC patients. A total 46,415 AS events including 10,601 genes in 537 patients with KIRC were identified. In univariate Cox regression analysis, 13,362 survival associated AS events and 8,694 survival-specific mRNAs were detected. Common 3,105 genes were screen by overlapping 13,362 survival associated AS events and 8,694 survival-specific mRNAs. The Pearson correlation analysis suggested that 13 genes were significantly correlated with AS events (Pearson correlation coefficient >0.8 or <-0.8). Then, We conducted multivariate Cox regression analyses to select the potential prognostic AS genes. Seven genes were identified to be significantly related to OS. A prognostic model based on seven genes was constructed. The area under the ROC curve was 0.767. In the current study, a robust prognostic prediction model was constructed for KIRC patients, and the findings revealed that the AS events could act as potential prognostic biomarkers for KIRC.
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Empalme Alternativo , Biomarcadores de Tumor/genética , Carcinoma de Células Renales/genética , Neoplasias Renales/genética , ARN Mensajero/genética , Sistemas de Transporte de Aminoácidos Básicos/genética , Sistemas de Transporte de Aminoácidos Neutros/genética , Apolipoproteína B-100/genética , Acuaporina 1/genética , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/terapia , Biología Computacional , Bases de Datos Genéticas , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Predisposición Genética a la Enfermedad , Humanos , Queratinas/genética , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Neoplasias Renales/terapia , Pronóstico , Mapas de Interacción de Proteínas , RNA-Seq , Receptores Adrenérgicos alfa 1/genética , Medición de Riesgo , Factores de Riesgo , Transducción de Señal/genética , Estearoil-CoA Desaturasa/genética , Factores de Tiempo , TranscriptomaRESUMEN
Long interspersed nuclear elements (LINE-1) is now considered as the only active autonomous mobile DNA in humans, LINE-1 retrotransposition activities are associated with and fluctuate during cancer initiation and progression; however, the mechanism underlying the increased LINE-1 activity in cancer is poorly understood. SAMHD1 has been reported to be a potent inhibitor of LINE-1 retrotransposition, and SAMHD1 mutations are frequently associated with cancer development. To gain insights on whether cancer-related SAMHD1 mutants affect LINE-1 activity, we explored the biochemical and cellular properties of some human mutants known correlate with the development of cancer. Most of the tested SAMHD1 cancer-related mutations were defective in LINE-1 inhibition. Interestingly we also found that SAMHD1 mutant K288T was defective for dNTPase activity but showed potent activity against LINE-1 retrotransposition. These findings suggest that LINE-1 inhibition does not depend solely on the dNTPase activity of SAMHD1. In contrast, SAMHD1's ability to inhibit ORF2p-mediated LINE-1 RNP reverse transcription was correlated with SAMHD1-mediated LINE-1 inhibition. Together, our data could also facilitate the deeper understanding for the inhibition of endogenous LINE-1 elements by SAMHD1.
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Elementos de Nucleótido Esparcido Largo/genética , Neoplasias/genética , Proteína 1 que Contiene Dominios SAM y HD/genética , Células Cultivadas , Células HEK293 , Humanos , Mutación , Proteínas Recombinantes/genéticaRESUMEN
OBJECTIVE: The current meta-analysis was performed to evaluate the safety and efficacy of retroperitoneoscopic renal pedicle ligation of lymphatic disconnection (RRPLD) compared with open surgery (OS) in the treatment of chyluria. MATERIALS AND METHODS: Relevant studies were retrieved from MEDLINE, EMBASE, -SCOPUS, the Cochrane library and two Chinese literature database resources (Wanfang and CNKI) in March 2016. All eligible studies comparing RRPLD with OS for chyluria were included in this study. The main outcome including operative time, blood loss, postoperative (PO) intestinal recovery time, PO drainage duration, PO hospital stay, PO time of returning to work, PO bed time, and complications as well as rate of recurrence for RRPLD and OS were pooled using the Revman software. RESULTS: Twelve studies with a total of 620 patients were included in this meta-analysis. Of these patients, 365 and 255 had undergone renal pedicle lymphatic ligation via RRPLD and OS, respectively. There were significant reductions in operative time, PO intestinal recovery time, PO drainage duration, PO hospital stay, PO time of returning to work, and possible reductions in intraoperative blood loss intraoperative and PO complications for RRPLD compared to OS. However, other outcome variables, such as PO time in bed and PO recurrence, were not found to be statistically significant for either group. CONCLUSION: Compared with OS, RRPLD has several advantages such as shorter operative time, less intraoperative blood loss, and lower incidence of complications. Thus, it may be an efficacious and safe therapeutic modality for chyluria.
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Quilo , Riñón/cirugía , Laparoscopía , Vasos Linfáticos/cirugía , Pérdida de Sangre Quirúrgica , Humanos , Intestinos/fisiología , Laparoscopía/efectos adversos , Tiempo de Internación , Ligadura , Tempo Operativo , Complicaciones Posoperatorias/etiología , Recuperación de la Función , Recurrencia , Espacio Retroperitoneal , Orina , Procedimientos Quirúrgicos Urológicos/efectos adversos , Procedimientos Quirúrgicos Urológicos/métodosRESUMEN
OBJECTIVE: To assess the safety of the super-mini percutaneous nephrolithotomy (SMP) versus the minimally invasive percutaneous nephrolithotomy (MPCNL) in the treatment of pediatric renal calculus. METHODS: We retrospectively reviewed the electronic records of pediatric patients who underwent treatment for renal stones by either SMP or MPCNL from May 2015 to May 2016. We compared the safety of the 2 surgical procedures in the treatment of renal calculus in children by using the generalized estimating equation (GEE) multivariate regression analysis, in which the exposures are the surgical procedures and postoperative adverse events (postoperative complications, fever, and WBC counts) are set as outcome variables. RESULTS: The study included 39 patients (26 boys and 13 girls), of which 22 underwent MPCNL and 17 underwent SMP, with a mean age of 110.05 ± 45.01 and 93.18 ± 41.72 months, respectively. In the univariate logistic regression model, the surgical procedures showed no significant association with postoperative complications (95% CI 0.0-1.5), fever (95% CI 0.1-2.1), postoperative peripheral WBC (95% CI 0.1-2.2). In the multiple logistic regression analysis, there was an insignificant association between surgical methods and postoperative complications (95% CI 0.28-1.1), fever (95% CI 0.1-1.2), and postoperative peripheral WBC (95% CI 0.03-1.8). While using GEE with multiple dependent variables and MPCNL as a reference, the OR of adverse events was 0.15 and the 95% CI were 0.04-0.55. CONCLUSIONS: Compared to MPCNL, SMP has a lower incidence of postoperative complications and appears to be a safer treatment for children with kidney stones.
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Cálculos Renales/cirugía , Nefrolitotomía Percutánea/métodos , Complicaciones Posoperatorias/prevención & control , Niño , Preescolar , Femenino , Humanos , Incidencia , Tiempo de Internación , Masculino , Análisis Multivariante , Tempo Operativo , Seguridad del Paciente , Periodo Posoperatorio , Estudios Retrospectivos , Factores de RiesgoRESUMEN
The lentiviral accessory proteins Vpx and Vpr are known to utilize CRL4 (DCAF1) E3 ligase to induce the degradation of the host restriction factor SAMHD1 or host helicase transcription factor (HLTF), respectively. Selective disruption of viral CRL4 (DCAF1) E3 ligase could be a promising antiviral strategy. Recently, we have determined that posttranslational modification (neddylation) of Cullin-4 is required for the activation of Vpx-CRL4 (DCAF1) E3 ligase. However, the mechanism of Vpx/Vpr-CRL4 (DCAF1) E3 ligase assembly is still poorly understood. Here, we report that zinc coordination is an important regulator of Vpx-CRL4 E3 ligase assembly. Residues in a conserved zinc-binding motif of Vpx were essential for the recruitment of the CRL4 (DCAF1) E3 complex and Vpx-induced SAMHD1 degradation. Importantly, altering the intracellular zinc concentration by treatment with the zinc chelator N,N,N'-tetrakis-(2'-pyridylmethyl)ethylenediamine (TPEN) potently blocked Vpx-mediated SAMHD1 degradation and inhibited wild-type SIVmac (simian immunodeficiency virus of macaques) infection of myeloid cells, even in the presence of Vpx. TPEN selectively inhibited Vpx and DCAF1 binding but not the Vpx-SAMHD1 interaction or Vpx virion packaging. Moreover, we have shown that zinc coordination is also important for the assembly of the HIV-1 Vpr-CRL4 E3 ligase. In particular, Vpr zinc-binding motif mutation or TPEN treatment efficiently inhibited Vpr-CRL4 (DCAF1) E3 ligase assembly and Vpr-mediated HLTF degradation or Vpr-induced G2 cell cycle arrest. Collectively, our study sheds light on a conserved strategy by the viral proteins Vpx and Vpr to recruit host CRL4 (DCAF1) E3 ligase, which represents a target for novel anti-human immunodeficiency virus (HIV) drug development.IMPORTANCE The Vpr and its paralog Vpx are accessory proteins encoded by different human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) lentiviruses. To facilitate viral replication, Vpx has evolved to induce SAMHD1 degradation and Vpr to mediate HLTF degradation. Both Vpx and Vpr perform their functions by recruiting CRL4 (DCAF1) E3 ligase. In this study, we demonstrate that the assembly of the Vpx- or Vpr-CRL4 E3 ligase requires a highly conserved zinc-binding motif. This motif is specifically required for the DCAF1 interaction but not for the interaction of Vpx or Vpr with its substrate. Selective disruption of Vpx- or Vpr-CRL4 E3 ligase function was achieved by zinc sequestration using N,N,N'-tetrakis-(2'-pyridylmethyl)ethylenediamine (TPEN). At the same time, zinc sequestration had no effect on zinc-dependent cellular protein functions. Therefore, information obtained from this study may be important for novel anti-HIV drug development.
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Proteínas Portadoras/metabolismo , Proteínas de Unión al GTP Monoméricas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/metabolismo , Línea Celular , Proteínas de Unión al ADN/metabolismo , Etilenodiaminas/farmacología , Puntos de Control de la Fase G2 del Ciclo Celular , Células HEK293 , Infecciones por VIH/virología , VIH-1/metabolismo , Interacciones Huésped-Patógeno , Humanos , Células Mieloides/virología , Proteínas Serina-Treonina Quinasas , Estructura Terciaria de Proteína , Proteína 1 que Contiene Dominios SAM y HD , Virus de la Inmunodeficiencia de los Simios/metabolismo , Factores de Transcripción/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética , Replicación Viral , Zinc/metabolismo , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
Coxsackievirus A16 (CV-A16), CV-A6, and enterovirus D68 (EV-D68) belong to the Picornaviridae family and are major causes of hand, foot, and mouth disease (HFMD) and pediatric respiratory disease worldwide. The biological characteristics of these viruses, especially their interplay with the host innate immune system, have not been well investigated. In this study, we discovered that the 3Cpro proteins from CV-A16, CV-A6, and EV-D68 bind melanoma differentiation-associated gene 5 (MDA5) and inhibit its interaction with MAVS. Consequently, MDA5-triggered type I interferon (IFN) signaling in the retinoic acid-inducible gene I-like receptor (RLR) pathway was blocked by the CV-A16, CV-A6, and EV-D68 3Cpro proteins. Furthermore, the CV-A16, CV-A6, and EV-D68 3Cpro proteins all cleave transforming growth factor ß-activated kinase 1 (TAK1), resulting in the inhibition of NF-κB activation, a host response also critical for Toll-like receptor (TLR)-mediated signaling. Thus, our data demonstrate that circulating HFMD-associated CV-A16 and CV-A6, as well as severe respiratory disease-associated EV-D68, have developed novel mechanisms to subvert host innate immune responses by targeting key factors in the RLR and TLR pathways. Blocking the ability of 3Cpro proteins from diverse enteroviruses and coxsackieviruses to interfere with type I IFN induction should restore IFN antiviral function, offering a potential novel antiviral strategy.IMPORTANCE CV-A16, CV-A6, and EV-D68 are emerging pathogens associated with hand, foot, and mouth disease and pediatric respiratory disease worldwide. The pathogenic mechanisms of these viruses are largely unknown. Here we demonstrate that the CV-A16, CV-A6, and EV-D68 3Cpro proteins block MDA5-triggered type I IFN induction. The 3Cpro proteins of these viruses bind MDA5 and inhibit its interaction with MAVS. In addition, the CV-A16, CV-A6, and EV-D68 3Cpro proteins cleave TAK1 to inhibit the NF-κB response. Thus, our data demonstrate that circulating HFMD-associated CV-A16 and CV-A6, as well as severe respiratory disease-associated EV-D68, have developed a mechanism to subvert host innate immune responses by simultaneously targeting key factors in the RLR and TLR pathways. These findings indicate the potential merit of targeting the CV-A16, CV-A6, and EV-D68 3Cpro proteins as an antiviral strategy.
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Cisteína Endopeptidasas/metabolismo , Enterovirus/inmunología , Enterovirus/patogenicidad , Interacciones Huésped-Patógeno , Evasión Inmune , Inmunidad Innata , Helicasa Inducida por Interferón IFIH1/antagonistas & inhibidores , Proteínas Virales/metabolismo , Proteasas Virales 3C , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Proteolisis , Transducción de SeñalRESUMEN
hMOF (MYST1), a histone acetyltransferase (HAT), forms at least two distinct multiprotein complexes in human cells. The male specific lethal (MSL) HAT complex plays a key role in dosage compensation in Drosophila and is responsible for histone H4K16ac in vivo. We and others previously described a second hMOF-containing HAT complex, the non-specific lethal (NSL) HAT complex. The NSL complex has a broader substrate specificity, can acetylate H4 on K16, K5, and K8. The WD (tryptophan-aspartate) repeat domain 5 (WDR5) and host cell factor 1 (HCF1) are shared among members of the MLL/SET (mixed-lineage leukemia/set-domain containing) family of histone H3K4 methyltransferase complexes. The presence of these shared subunits raises the possibility that there are functional links between these complexes and the histone modifications they catalyze; however, the degree to which NSL and MLL/SET influence one another's activities remains unclear. Here, we present evidence from biochemical assays and knockdown/overexpression approaches arguing that the NSL HAT promotes histone H3K4me2 by MLL/SET complexes by an acetylation-dependent mechanism. In genomic experiments, we identified a set of genes including ANKRD2, that are affected by knockdown of both NSL and MLL/SET subunits, suggested they are co-regulated by NSL and MLL/SET complexes. In ChIP assays, we observe that depletion of the NSL subunits hMOF or NSL1 resulted in a significant reduction of both H4K16ac and H3K4me2 in the vicinity of the ANKRD2 transcriptional start site proximal region. However, depletion of RbBP5 (a core component of MLL/SET complexes) only reduced H3K4me2 marks, but not H4K16ac in the same region of ANKRD2, consistent with the idea that NSL acts upstream of MLL/SET to regulate H3K4me2 at certain promoters, suggesting coordination between NSL and MLL/SET complexes is involved in transcriptional regulation of certain genes. Taken together, our results suggest a crosstalk between the NSL and MLL/SET complexes in cells.
Asunto(s)
Histona Acetiltransferasas/genética , N-Metiltransferasa de Histona-Lisina/genética , Complejos Multiproteicos/genética , Proteína de la Leucemia Mieloide-Linfoide/genética , Animales , Células HEK293 , Histona Acetiltransferasas/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Metilación , Complejos Multiproteicos/aislamiento & purificación , Complejos Multiproteicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas , Estructura Terciaria de Proteína , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Especificidad por SustratoRESUMEN
Changes in chromatin structure and heritably regulating the gene expression by epigenetic mechanisms, such as histone post-translational modification, are involved in most cellular biological processes. Thus, abnormal regulation of epigenetics is implicated in the occurrence of various diseases, including cancer. Human MOF (males absent on the first) is a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs). As a catalytic subunit, MOF can form at least two distinct multiprotein complexes (MSL and NSL) in human cells. Both complexes can acetylate histone H4 at lysine 16 (H4K16); however, the NSL complex possesses broader substrate specificity and can also acetylate histone H4 at lysines 5 and 8 (H4K5 and H4K8), suggesting the complexity of the intracellular functions of MOF. Silencing of MOF in cells leads to genomic instability, inactivation of gene transcription, defective DNA damage repair and early embryonic lethality. Unbalanced MOF expression and its corresponding acetylation of H4K16 have been found in certain primary cancer tissues, including breast cancer, medulloblastoma, ovarian cancer, renal cell carcinoma, colorectal carcinoma, gastric cancer, as well as non-small cell lung cancer. In this review, we provide a brief overview of MOF and its corresponding histone acetylation, introduce recent research findings that link MOF functions to tumorigenesis and speculate on the potential role that may be relevant to tumorigenic pathways.
Asunto(s)
Carcinogénesis/metabolismo , Histona Acetiltransferasas/metabolismo , Acetilación , Animales , Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Histona Acetiltransferasas/genética , Histonas/metabolismo , Humanos , Procesamiento Proteico-PostraduccionalRESUMEN
BACKGROUND: Diabetic nephropathy (DN) is a major microvascular complication of diabetes and has become the leading cause of end-stage renal disease worldwide. A considerable number of DN patients have experienced irreversible end-stage renal disease progression due to the inability to diagnose the disease early. Therefore, reliable biomarkers that are helpful for early diagnosis and treatment are identified. The migration of immune cells to the kidney is considered to be a key step in the progression of DN-related vascular injury. Therefore, finding markers in this process may be more helpful for the early diagnosis and progression prediction of DN. METHODS: The gene chip data were retrieved from the GEO database using the search term ' diabetic nephropathy '. The ' limma ' software package was used to identify differentially expressed genes (DEGs) between DN and control samples. Gene set enrichment analysis (GSEA) was performed on genes obtained from the molecular characteristic database (MSigDB. The R package 'WGCNA' was used to identify gene modules associated with tubulointerstitial injury in DN, and it was crossed with immune-related DEGs to identify target genes. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed on differentially expressed genes using the 'ClusterProfiler' software package in R. Three methods, least absolute shrinkage and selection operator (LASSO), support vector machine recursive feature elimination (SVM-RFE) and random forest (RF), were used to select immune-related biomarkers for diagnosis. We retrieved the tubulointerstitial dataset from the Nephroseq database to construct an external validation dataset. Unsupervised clustering analysis of the expression levels of immune-related biomarkers was performed using the 'ConsensusClusterPlus 'R software package. The urine of patients who visited Dongzhimen Hospital of Beijing University of Chinese Medicine from September 2021 to March 2023 was collected, and Elisa was used to detect the mRNA expression level of immune-related biomarkers in urine. Pearson correlation analysis was used to detect the effect of immune-related biomarker expression on renal function in DN patients. RESULTS: Four microarray datasets from the GEO database are included in the analysis : GSE30122, GSE47185, GSE99340 and GSE104954. These datasets included 63 DN patients and 55 healthy controls. A total of 9415 genes were detected in the data set. We found 153 differentially expressed immune-related genes, of which 112 genes were up-regulated, 41 genes were down-regulated, and 119 overlapping genes were identified. GO analysis showed that they were involved in various biological processes including leukocyte-mediated immunity. KEGG analysis showed that these target genes were mainly involved in the formation of phagosomes in Staphylococcus aureus infection. Among these 119 overlapping genes, machine learning results identified AGR2, CCR2, CEBPD, CISH, CX3CR1, DEFB1 and FSTL1 as potential tubulointerstitial immune-related biomarkers. External validation suggested that the above markers showed diagnostic efficacy in distinguishing DN patients from healthy controls. Clinical studies have shown that the expression of AGR2, CX3CR1 and FSTL1 in urine samples of DN patients is negatively correlated with GFR, the expression of CX3CR1 and FSTL1 in urine samples of DN is positively correlated with serum creatinine, while the expression of DEFB1 in urine samples of DN is negatively correlated with serum creatinine. In addition, the expression of CX3CR1 in DN urine samples was positively correlated with proteinuria, while the expression of DEFB1 in DN urine samples was negatively correlated with proteinuria. Finally, according to the level of proteinuria, DN patients were divided into nephrotic proteinuria group (n = 24) and subrenal proteinuria group. There were significant differences in urinary AGR2, CCR2 and DEFB1 between the two groups by unpaired t test (P < 0.05). CONCLUSIONS: Our study provides new insights into the role of immune-related biomarkers in DN tubulointerstitial injury and provides potential targets for early diagnosis and treatment of DN patients. Seven different genes ( AGR2, CCR2, CEBPD, CISH, CX3CR1, DEFB1, FSTL1 ), as promising sensitive biomarkers, may affect the progression of DN by regulating immune inflammatory response. However, further comprehensive studies are needed to fully understand their exact molecular mechanisms and functional pathways in DN.
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RNA modifications play a crucial regulatory role in a variety of biological processes and are closely related to numerous diseases, including cancer. The diversity of metabolites in serum makes it a favored biofluid for biomarkers discovery. In this work, a robust and accurate hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) approach was established for simultaneous determination of dimethylated nucleosides in human serum. Using the established method, we were able to accurately quantify the concentrations of N6-2'-O-dimethyladenosine (m6Am), N2,N2-dimethylguanosine (m2,2G), and 5,2'-O-dimethyluridine (m5Um) in serum samples from 53 healthy controls, 57 advanced colorectal adenoma patients, and 39 colorectal cancer (CRC) patients. The results showed that, compared with healthy controls and advanced colorectal adenoma patients, the concentrations of m6Am and m2,2G were increased in CRC patients, while the concentration of m5Um was decreased in CRC patients. These results indicate that these three dimethylated nucleosides could be potential biomarkers for early detection of colorectal cancer. Interestingly, the level of m5Um was gradually decreased from healthy controls to advanced colorectal adenoma patients to CRC patients, indicating m5Um could also be used to evaluate the level of malignancy of colorectal tumor. In addition, this study will contribute to the investigation on the regulatory mechanisms of RNA dimethylation in the onset and development of colorectal cancer.