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Background: Chemotherapy resistance is a barrier to effective cancer prognoses. Cisplatin (CDDP) resistance is a major challenge for esophageal cancer (EC) therapy. A deeper understanding of the fundamental mechanisms of cisplatin resistance and improved targeting strategies are required in clinical settings. This study was performed to identify and characterize a marker of cisplatin resistance in EC cells. Method: KYSE140 and Eca-109 cells were subjected to escalating concentrations of cisplatin, resulting in the development of cisplatin-resistant KYSE140/CDDP and Eca-109/CDDP cell lines, respectively. RNA Sequencing (RNA-seq) was utilized to screen for the genes exhibiting differential expression between cisplatin-resistant and parental cells. Reverse transcription quantitative PCR was conducted to assess gene expression, and western blotting was employed to analyze protein levels. A sphere-formation assay was performed to validate tumor cell stemness. Cell counting kit-8 (CCK-8) experiments were conducted to confirm the sensitivity of cells to cisplatin. We examined the relationship between target genes and the clinicopathological features of patients with EC. Furthermore, the expression of target genes in EC tissues was evaluated via western blotting and fluorescence probe in situ hybridization (FISH). Results: KYNU was upregulated in cisplatin-resistant EC cells (KYSE140/CDDP and Eca-109/CDDP cells) and in EC tissues compared to that in the respective parental cell lines (KYSE140 and Eca-109 cells) and non-carcinoma tissues. Downregulation of KYNU increased cell sensitivity to cisplatin and suppressed tumor stemness, whereas abnormal KYNU expression had the opposite effect. KYNU expression was correlated with the expression of tumor stemness-associated factors (SOX2, Nanog, and OCT4) and the tumor size. Conclusions: KYNU may promote drug resistance in EC by regulating cancer stemness, and could serve as a biomarker and therapeutic target for EC.
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Heat shock protein 90 (Hsp90) is a tumor marker that accelerates cancer growth by disrupting protein homeostasis. However, concerns such as low clinical efficacy and drug resistance continue to be obstacles to the successful marketing of Hsp90 inhibitors. The cytoprotective function of autophagy has been identified as one of the mechanisms by which tumor cells gain resistance to chemotherapy. JD-02 was identified as a new Hsp90 inhibitor that suppressed colorectal cancer (CRC) growth by lowering client protein levels in vivo and in vitro. We found that JD-02 increased cellular autophagy, which inhibited apoptosis. JD-02 enhanced cytoprotective autophagy and regulated apoptotic suppression by increasing intracellular reactive oxygen species and inhibiting SRC protein levels, as demonstrated by quantitative proteomics, bioinformatic analysis, western blotting, and flow cytometry. This effect was reversed by autophagy inhibition. Therefore, due to the synergistic effects of Hsp90 and autophagy inhibitors in efficiently activating apoptotic pathways, they could potentially serve as promising therapeutic options for CRC.
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Autofagia , Neoplasias Colorretais , Proteínas de Choque Térmico HSP90 , Espécies Reativas de Oxigênio , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo , Quinases da Família src/antagonistas & inibidores , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Plants have evolved a sophisticated immune system to defend against invasion by pathogens. In response, pathogens deploy copious effectors to evade the immune responses. However, the molecular mechanisms used by pathogen effectors to suppress plant immunity remain unclear. Herein, we report that an effector secreted by Ralstonia solanacearum, RipAK, modulates the transcriptional activity of the ethylene-responsive factor ERF098 to suppress immunity and dehydration tolerance, which causes bacterial wilt in pepper (Capsicum annuum L.) plants. Silencing ERF098 enhances the resistance of pepper plants to R. solanacearum infection not only by inhibiting the host colonization of R. solanacearum but also by increasing the immunity and tolerance of pepper plants to dehydration and including the closure of stomata to reduce the loss of water in an abscisic acid signal-dependent manner. In contrast, the ectopic expression of ERF098 in Nicotiana benthamiana enhances wilt disease. We also show that RipAK targets and inhibits the ERF098 homodimerization to repress the expression of salicylic acid-dependent PR1 and dehydration tolerance-related OSR1 and OSM1 by cis-elements in their promoters. Taken together, our study reveals a regulatory mechanism used by the R. solanacearum effector RipAK to increase virulence by specifically inhibiting the homodimerization of ERF098 and reprogramming the transcription of PR1, OSR1, and OSM1 to boost susceptibility and dehydration sensitivity. Thus, our study sheds light on a previously unidentified strategy by which a pathogen simultaneously suppresses plant immunity and tolerance to dehydration by secreting an effector to interfere with the activity of a transcription factor and manipulate plant transcriptional programs.
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Capsicum , Ralstonia solanacearum , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ralstonia solanacearum/fisiologia , Desidratação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Imunidade Vegetal/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Capsicum/metabolismo , Resistência à Doença/genéticaRESUMO
Hyperuricemia, caused by an imbalance between the rates of production and excretion of uric acid (UA), may greatly increase the mortality rates in patients with cardiovascular and cerebrovascular diseases. Herein, for fast-acting and long-lasting hyperuricemia treatment, armored red blood cell (RBC) biohybrids, integrated RBCs with proximal, cascaded-enzymes of urate oxidase (UOX) and catalase (CAT) encapsulated within ZIF-8 framework-based nanoparticles, have been fabricated based on a super-assembly approach. Each component is crucial for hyperuricemia treatment: 1) RBCs significantly increase the circulation time of nanoparticles; 2) ZIF-8 nanoparticles-based superstructure greatly enhances RBCs resistance against external stressors while preserving native RBC properties (such as oxygen carrying capability); 3) the ZIF-8 scaffold protects the encapsulated enzymes from enzymatic degradation; 4) no physical barrier exists for urate diffusion, and thus allow fast degradation of UA in blood and neutralizes the toxic by-product H2 O2 . In vivo results demonstrate that the biohybrids can effectively normalize the UA level of an acute hyperuricemia mouse model within 2 h and possess a longer elimination half-life (49.7 ± 4.9 h). They anticipate that their simple and general method that combines functional nanomaterials with living cell carriers will be a starting point for the development of innovative drug delivery systems.
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Hiperuricemia , Estruturas Metalorgânicas , Humanos , Animais , Camundongos , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Modelos Animais de Doenças , Ácido Úrico , Eritrócitos/metabolismoRESUMO
BACKGROUND: AT-533 is a novel heat shock protein 90 inhibitor that exerting anti-inflammatory, antiviral, and antitumor efficacy. Furthermore, the gel made of AT-533 as raw material named AT-533 gel has the function of repairing keratitis and dermatitis caused by herpes virus infection. However, the acute safety evaluation of AT-533 and AT-533 gel has not been conducted. METHODS AND RESULTS: Herein, we performed acute toxicological studies of AT-533 and AT-533 gel in Sprague-Dawley rats. Fifteen-day acute toxicity study of AT-533 was conducted in both male and female Sprague-Dawley rats at doses of 5, 50, 250 and 500 mg/kg and AT-533 gel at 5 g/kg in the study. During experiment, food consumption and mortality were observed and body weight, hematology, serum biochemistry and histopathological assessment of rats were carried out. No abnormal changes were observed in rats percutaneously treated with AT-533 at 5 mg/kg and 50 mg/kg and AT-533 gel. However, loss of appetite and body weight, adverse reactions, toxicologically relevant alterations in hematology and biochemistry were found in rats percutaneously treated with AT-533 at 250 mg/kg and 500 mg/kg during 15-day acute dermic toxicity study. CONCLUSIONS: The aforementioned results suggested that the LD50 of AT-533 is 228.382 mg/kg and the LD50 of AT-533 gel is greater than 5 g/kg. These findings indicated that AT-533 is non-toxic in rats when the dose less than 50 mg/kg and AT-533 gel can be considered a gel with no toxicity at doses less than 5 g/kg.
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Ratos Sprague-Dawley , Ratos , Masculino , Feminino , Animais , Dose Letal Mediana , Peso Corporal , Administração OralRESUMO
BACKGROUND: Melanoma is the deadliest form of skin cancer. Heat shock protein 90 (Hsp90) is highly expressed in human melanoma. Hsp90 inhibitors can suppress the growth of human melanoma A375 cells; however, the underlying mechanism remains unclear. METHODS: A375 cells were treated with SNX-2112, an Hsp90 inhibitor, for 48 h, and whole-transcriptome sequencing was performed. RESULTS: A total of 2,528 differentially expressed genes were identified, including 895 upregulated and 1,633 downregulated genes. Pathway enrichment analyses of differentially expressed mRNAs identified the extracellular matrix (ECM)-receptor interaction pathway as the most significantly enriched pathway. The ECM receptor family mainly comprises integrins (ITGs) and collagens (COLs), wherein ITGs function as the major cell receptors for COLs. 19 upregulated miRNAs were found to interact with 6 downregulated ITG genes and 8 upregulated miRNAs were found to interact with 3 downregulated COL genes. 9 differentially expressed circRNAs in SNX-2112-treated A375 cells were identified as targets of the ITG- and COL-related miRNAs. Based on the differentially expressed circRNAs, miRNAs, and mRNAs, ITGs- and COL-based circRNA-miRNA-mRNA regulatory networks were mapped, revealing a novel regulatory mechanism of Hsp90-regulated melanoma. CONCLUSION: Targeting the ITG-COL network is a promising approach to the treatment of melanoma.
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Rationale: The role of circadian clock in pituitary tumorigenesis remains elusive. Here we investigate whether and how circadian clock modulates the development of pituitary adenomas. Methods and Results: We found altered expression of pituitary clock genes in patients with pituitary adenomas. In particular, PER2 is prominently upregulated. Further, jetlagged mice with PER2 upregulation have accelerated growth of GH3 xenograft tumor. Conversely, loss of Per2 protects mice against developing estrogen-induced pituitary adenoma. Similar antitumor effect is observed for SR8278, a chemical that can decrease pituitary PER2 expression. RNA-seq analysis suggests involvement of cell cycle disturbance in PER2 regulation of pituitary adenoma. Subsequent in vivo and cell-based experiments validate that PER2 induces pituitary expression of Ccnb2, Cdc20 and Espl1 (three cell cycle genes) to facilitate cell cycle progression and inhibit apoptosis, thereby promoting pituitary tumorigenesis. Mechanistically, PER2 regulates the transcription of Ccnb2, Cdc20 and Espl1 through enhancing the transcriptional activity of HIF-1α. HIF-1α trans-activates Ccnb2, Cdc20 and Espl1 via direct binding to its specific response element in the gene promoters. Conclusion: PER2 integrates circadian disruption and pituitary tumorigenesis. These findings advance our understanding of crosstalk between circadian clock and pituitary adenomas and highlight the relevance of clock-based approaches in disease management.
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Relógios Circadianos , Neoplasias Hipofisárias , Humanos , Camundongos , Animais , Neoplasias Hipofisárias/genética , Ritmo Circadiano/genética , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Relógios Circadianos/genética , Proteínas de Ciclo Celular/metabolismo , Carcinogênese/genética , Transformação Celular Neoplásica/genéticaRESUMO
PURPOSE: Esophageal squamous cell carcinoma (ESCC) remains one of the most common causes of cancer death due to the lack of effective therapeutic options. New targets and the targeted drugs are required to be identified and developed. METHODS: Highly expressed genes in ESCA were identified using the edgeR package from public datasets. Immunostaining assay verified the high expression level of EFNA1 in ESCC. CCK-8, colony formation and wound healing assays were performed to examine the role of EFNA1 and EPHA2 in ESCC progression. Cell cycle was analyzed by flow cytometry and autophagy activation was determined by autophagolysosome formation using transmission electron microscopy. The small molecule targeting to EFNA1 was identified by molecular docking and the anti-tumor effects were verified by in vitro and in vivo models with radiation treatment. RESULTS: EFNA1 was highly expressed in esophageal cancer and significantly associated with poor prognosis. Downregulation of EFNA1 remarkably inhibited cell proliferation and migration. Furthermore, decreased EFNA1 significantly suppressed the expression of cMYC along with its representative downstream genes involved in cell cycle, and activated autophagy. Similar effects on ESCC progression were obtained from knockdown of the corresponding receptor, EPHA2. The potential small molecule targeting to EFNA1, salvianolic acid A (SAA), could significantly suppress ESCC progression and increase the sensitivity to radiotherapy. CONCLUSION: We revealed that EFNA1 facilitated the ESCC progression via the possible mechanism of activating cMYC-modulated cell proliferation and suppressing autophagy, and identified SAA as a potential drug targeting EFNA1, providing new options for the future treatments for ESCC patients.
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BACKGROUND & AIMS: Temporal oscillations in intestinal nutrient processing and absorption are coordinated by the local clock, which leads to the hypothesis that the intestinal clock has major impacts on shaping peripheral rhythms via diurnal nutritional signals. Here, we investigate the role of the intestinal clock in controlling liver rhythmicity and metabolism. METHODS: Transcriptomic analysis, metabolomics, metabolic assays, histology, quantitative (q)PCR, and immunoblotting were performed with Bmal1-intestine-specific knockout (iKO), Rev-erba-iKO, and control mice. RESULTS: Bmal1 iKO caused large-scale reprogramming of the rhythmic transcriptome of mouse liver with a limited effect on its clock. In the absence of intestinal Bmal1, the liver clock was resistant to entrainment by inverted feeding and a high-fat diet. Importantly, Bmal1 iKO remodelled diurnal hepatic metabolism by shifting to gluconeogenesis from lipogenesis during the dark phase, leading to elevated glucose production (hyperglycaemia) and insulin insensitivity. Conversely, Rev-erba iKO caused a diversion to lipogenesis from gluconeogenesis during the light phase, resulting in enhanced lipogenesis and an increased susceptibility to alcohol-related liver injury. These temporal diversions were attributed to disruption of hepatic SREBP-1c rhythmicity, which was maintained via gut-derived polyunsaturated fatty acids produced by intestinal FADS1/2 under the control of a local clock. CONCLUSIONS: Our findings establish a pivotal role for the intestinal clock in dictating liver rhythmicity and diurnal metabolism, and suggest targeting intestinal rhythms as a new avenue for improving metabolic health. IMPACT AND IMPLICATIONS: Our findings establish the centrality of the intestinal clock among peripheral tissue clocks, and associate liver-related pathologies with its malfunction. Clock modifiers in the intestine are shown to modulate liver metabolism with improved metabolic parameters. Such knowledge will help clinicians improve the diagnosis and treatment of metabolic diseases by incorporating intestinal circadian factors.
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Relógios Circadianos , Camundongos , Animais , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Fígado/patologia , Glucose/metabolismo , Etanol/metabolismo , Regulação da Expressão GênicaRESUMO
The triple-negative breast cancer (TNBC) microenvironment makes a feature of aberrant vasculature, high interstitial pressure, and compact extracellular matrix, which combine to reduce the delivery and penetration of therapeutic agents, bringing about incomplete elimination of cancer cells. Herein, employing the tumor penetration strategy of size-shrinkage combined with ligand modification, we constructed a photothermal nanocluster for cascaded deep penetration in tumor parenchyma and efficient eradication of TNBC cells. In our approach, the photothermal agent indocyanine green (ICG) is laded in human serum albumin (HSA), which is cross-linked by a thermally labile azo linker (VA057) and then further modified with a tumor homing/penetrating tLyP-1 peptide (HP), resulting in a TNBC-targeting photothermal-responsive size-switchable albumin nanocluster (ICG@HSA-Azo-HP). Aided by the enhanced permeability and retention effect and guidance of HP, the ca. 149 nm nanoclusters selectively accumulate in the tumor site and then, upon mild irradiation with the 808 nm laser, disintegrate into 11 nm albumin fractions that possess enhanced intratumoral diffusion ability. Meanwhile, HP initiates the CendR pathway among the nutrient-deficient tumor cells and facilitates the transcellular delivery of the nanocluster and its disintegrated fractions for subsequent therapy. By employing this size-shrinkage and peptide-initiated transcytosis strategy, ICG@HSA-Azo-HP possesses excellent penetration capabilities and shows extensive penetration depth in three-dimensional multicellular tumor spheroids after irradiation. Moreover, with a superior photothermal conversion effect, the tumor-penetrating nanocluster can implement effective photothermal therapy throughout the tumor tissue under a second robust irradiation. Both in vivo orthotopic and ectopic TNBC therapy confirmed the efficient tumor inhibition of ICG@HSA-Azo-HP after dual-stage irradiation. The synergistic penetration strategy of on-demanded size-shrinkage and ligand guidance accompanied by clinically feasible NIR irradiation provides a promising approach for deep-penetrating TNBC therapy.
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Hipertermia Induzida , Nanopartículas , Neoplasias de Mama Triplo Negativas , Albuminas , Animais , Linhagem Celular Tumoral , Humanos , Hipertermia Induzida/métodos , Verde de Indocianina/farmacologia , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/metabolismo , Fototerapia/métodos , Terapia Fototérmica , Albumina Sérica Humana , Neoplasias de Mama Triplo Negativas/terapia , Microambiente TumoralRESUMO
Improved understanding of the etiologies of delirium, a common and severe neuropsychiatric syndrome, would facilitate the disease prevention and treatment. Here, the authors invesitgate the role of circadian rhythms in the pathogenesis of delirium. They observe perturbance of circadian rhythms in mouse models of delirium and disrupted clock gene expression in patients with delirium. In turn, physiological and genetic circadian disruptions sensitize mice to delirium with aggravated cognitive impairment. Likewise, global deletion of E4bp4 (E4 promoter-binding protein), a clock gene markedly altered in delirium conditions, results in exacerbated delirium-associated cognitive decline. Cognitive decline in delirium models is attributed to microglial activation and impaired long-term potentiation in the hippocampus. Single-cell RNA-sequencing reveals microglia as the regulatory target of E4bp4. E4bp4 restrains microglial activation via inhibiting the ERK1/2 signaling pathway. Supporting this, mice lacking in microglial E4bp4 are delirious prone, whereas mice with E4bp4 specifically deleted in hippocampal CA1 neurons have a normal phenotype. Mechanistically, E4bp4 inhibits ERK1/2 signaling by trans-repressing Mapk1/3 (genes encoding ERK1/2) via direct binding to a D-box element in the promoter region. These findings define a causal role of clock dysfunction in delirium development and indicate E4bp4 as a regulator of cognition at the crosstalk between circadian clock and delirium.
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Relógios Circadianos , Delírio , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Ritmo Circadiano/genética , Cognição , CamundongosRESUMO
Bacterial wilt, a severe disease involving vascular system blockade, is caused by Ralstonia solanacearum. Although both plant immunity and dehydration tolerance might contribute to disease resistance, whether and how they are related remains unclear. Herein, we showed that immunity against R. solanacearum and dehydration tolerance are coupled and regulated by the CaPti1-CaERF3 module. CaPti1 and CaERF3 are members of the serine/threonine protein kinase and ethylene-responsive factor families, respectively. Expression profiling revealed that CaPti1 and CaERF3 were upregulated by R. solanacearum inoculation, dehydration stress, and exogenously applied abscisic acid (ABA). They in turn phenocopied each other in promoting resistance of pepper (Capsicum annuum) to bacterial wilt not only by activating salicylic acid-dependent CaPR1, but also by activating dehydration tolerance-related CaOSM1 and CaOSR1 and inducing stomatal closure to reduce water loss in an ABA signaling-dependent manner. Our yeast two hybrid assay showed that CaERF3 interacted with CaPti1, which was confirmed using co-immunoprecipitation, bimolecular fluorescence complementation, and pull-down assays. Chromatin immunoprecipitation and electrophoretic mobility shift assays showed that upon R. solanacearum inoculation, CaPR1, CaOSM1, and CaOSR1 were directly targeted and positively regulated by CaERF3 and potentiated by CaPti1. Additionally, our data indicated that the CaPti1-CaERF3 complex might act downstream of ABA signaling, as exogenously applied ABA did not alter regulation of stomatal aperture by the CaPti1-CaERF3 module. Importantly, the CaPti1-CaERF3 module positively affected pepper growth and the response to dehydration stress. Collectively, the results suggested that immunity and dehydration tolerance are coupled and positively regulated by CaPti1-CaERF3 in pepper plants to enhance resistance against R. solanacearum.
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Capsicum , Ralstonia solanacearum , Ácido Abscísico/metabolismo , Capsicum/genética , Capsicum/metabolismo , Desidratação , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ralstonia solanacearum/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
AIMS: This multicenter, open-label, randomized study (Registration No. ChiCTR-OCH-14004528) aimed to compare the efficacy and effects of oxcarbazepine (OXC) with levetiracetam (LEV) as monotherapies on patient quality of life and mental health for patients with newly diagnosed focal epilepsy from China. METHODS: Patients with newly diagnosed focal epilepsy who had experienced 2 or more unprovoked seizures at greater than a 24-h interval during the previous year were recruited. Participants were randomly assigned to the OXC group or LEV group. Efficacy, safety, quality of life, and mental health were evaluated over 12-week and 24-week periods. RESULTS: In total, we recruited 271 newly diagnosed patients from 23 centers. Forty-four patients were excluded before treatment for reasons. The rate of seizure freedom of OXC was significantly superior to that of LEV at 12 weeks and 24 weeks (p < 0.05). The quality of life (except for the seizure worry subsection) and anxiety scale scores also showed significant differences from before to after treatment in the OXC and LEV groups. CONCLUSIONS: OXC monotherapy may be more effective than LEV monotherapy in patients with newly diagnosed focal epilepsy. Both OXC and LEV could improve the quality of life and anxiety state in adult patients with focal epilepsy.
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Epilepsias Parciais , Qualidade de Vida , Adulto , Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Humanos , Levetiracetam/uso terapêutico , Oxcarbazepina/uso terapêutico , Convulsões/tratamento farmacológico , Resultado do TratamentoRESUMO
Herpes simplex virus type 1 (HSV-1) is a highly prevalent virus in humans and causes severe forms of inflammation, such as herpes simplex encephalitis (HSE). Pyroptosis is a new inflammatory cell death triggered by inflammasome and cysteine-requiring aspartate protease-1 (caspase-1) activation. Nonetheless, HSV-1 induces encephalitis, and cell death mechanisms are not understood. In this study, we confirmed for the first time that the DNA virus HSV-1 triggers Gasdermin D-dependent pyroptosis by activating NLR family pyrin domain containing 3 (NLRP3) inflammasomes in mouse microglia, leading to mature IL-1ß production and active caspase-1 (p10) release. Inhibition of microglial NLRP3 inflammasome activation suppressed HSV-1-induced Gasdermin D-dependent pyroptosis. In addition, NLRP3 and IL-1ß expression levels were significantly increased in the mouse model of herpes simplex encephalitis compared with normal mice without viral infection. Collectively, our data revealed that the activation of inflammasomes and GSDMD-dependent pyroptosis is the mechanism of HSV-1 inducing inflammation and provides treatment targets for viral inflammation.
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BACKGROUND: Identification of potential novel targets for reversing resistance to Epidermal Growth Factor Receptor (EGFR)-tyrosine kinase inhibitors (EGFR-TKIs) holds great promise for the treatment of relapsed lung adenocarcinoma (LUAD). In the present study, we aim to investigate the role of methyltransferase-like 7B (METTL7B) in inducing EGFR-TKIs resistance in LUAD and whether it could be a therapeutic target for reversing the resistance. METHODS: METTL7B-overexpressed LUAD cell lines, gefitinib and osimertinib-resistant Cell-Derived tumor Xenograft (CDX) and Patient-Derived tumor Xenograft (PDX) mouse models were employed to evaluate the role of METTL7B in TKIs resistance. Ultraperformance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) was used to identify the metabolites regulated by METTL7B. Methylated RNA immunoprecipitation (MeRIP)-qPCR analysis was performed to measure the N6-methyladenosine (m6A) status of mRNA of METTL7B targeted genes. Gold nanocluster-assisted delivery of siRNA targeting METTL7B (GNC-siMETTL7B) was applied to evaluate the effect of METTL7B in TKIs resistance. RESULTS: Increased expression of METTL7B was found in TKIs-resistant LUAD cells and overexpression of METTL7B in LUAD cells induced TKIs resistance both in vitro and in vivo. Activated ROS-metabolism was identified in METTL7B-overexpressed LUAD cells, accompanied with upregulated protein level of GPX4, HMOX1 and SOD1 and their enzymatic activities. Globally elevated m6A levels were found in METTL7B-overexpressed LUAD cells, which was reduced by knock-down of METTL7B. METTL7B induced m6A modification of GPX4, HMOX1 and SOD1 mRNA. Knock-down of METTL7B by siRNA re-sensitized LUAD cells to gefitinib and osimertinib both in vitro and in vivo. CONCLUSIONS: This study uncovered a new critical link in METTL7B, glutathione metabolism and drug resistance. Our findings demonstrated that METTL7B inhibitors could be used for reversing TKIs resistance in LUAD patients.
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Adenocarcinoma de Pulmão , Proteínas de Transporte , Receptores ErbB , Neoplasias Pulmonares , Inibidores de Proteínas Quinases , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Espectrometria de Massas em Tandem , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: Solid tumours respond poorly to immune checkpoint inhibitor (ICI) therapies. One major therapeutic obstacle is the immunosuppressive tumour microenvironment (TME). Cancer-associated fibroblasts (CAFs) are a key component of the TME and negatively regulate antitumour T-cell response. Here, we aimed to uncover the mechanism underlying CAFs-mediated tumour immune evasion and to develop novel therapeutic strategies targeting CAFs for enhancing ICI efficacy in oesophageal squamous cell carcinoma (OSCC) and colorectal cancer (CRC). DESIGN: Anti-WNT2 monoclonal antibody (mAb) was used to treat immunocompetent C57BL/6 mice bearing subcutaneously grafted mEC25 or CMT93 alone or combined with anti-programmed cell death protein 1 (PD-1), and the antitumour efficiency and immune response were assessed. CAFs-induced suppression of dendritic cell (DC)-differentiation and DC-mediated antitumour immunity were analysed by interfering with CAFs-derived WNT2, either by anti-WNT2 mAb or with short hairpin RNA-mediated knockdown. The molecular mechanism underlying CAFs-induced DC suppression was further explored by RNA-sequencing and western blot analyses. RESULTS: A negative correlation between WNT2+ CAFs and active CD8+ T cells was detected in primary OSCC tumours. Anti-WNT2 mAb significantly restored antitumour T-cell responses within tumours and enhanced the efficacy of anti-PD-1 by increasing active DC in both mouse OSCC and CRC syngeneic tumour models. Directly interfering with CAFs-derived WNT2 restored DC differentiation and DC-mediated antitumour T-cell responses. Mechanistic analyses further demonstrated that CAFs-secreted WNT2 suppresses the DC-mediated antitumour T-cell response via the SOCS3/p-JAK2/p-STAT3 signalling cascades. CONCLUSIONS: CAFs could suppress antitumour immunity through WNT2 secretion. Targeting WNT2 might enhance the ICI efficacy and represent a new anticancer immunotherapy.
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Fibroblastos Associados a Câncer/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Esofágicas/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteína Wnt2/metabolismo , Animais , Linfócitos T CD8-Positivos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células Dendríticas/fisiologia , Modelos Animais de Doenças , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Microambiente TumoralRESUMO
Background: Emerging evidence suggests that inflammatory response biomarkers are predictive factors that can improve the accuracy of colorectal cancer (CRC) prognoses. We aimed to evaluate the prognostic significance of C-reactive protein (CRP), the Glasgow Prognostic Score (GPS), and the CRP-to-albumin ratio (CAR) in CRC. Methods: Overall, 307 stage I-III CRC patients and 72 colorectal liver metastases (CRLM) patients were enrolled between October 2013 and September 2019. We investigated the correlation between the pretreatment CRP, GPS, and CAR and the clinicopathological characteristics. The Cox proportional hazards model was used for univariate or multivariate analysis to assess potential prognostic factors. A receiver operating characteristic (ROC) curve was constructed to evaluate the predictive value of each prognostic score. We established CRC survival nomograms based on the prognostic scores of inflammation. Results: The optimal cutoff levels for the CAR for overall survival (OS) in all CRC patients, stage I-III CRC patients, and CRLM patients were 0.16, 0.14, and 0.25, respectively. Kaplan-Meier analysis and log-rank tests demonstrated that patients with high CRP, CAR, and GPS had poorer OS in CRC, both in the cohorts of stage I-III patients and CRLM patients. In the different cohorts of CRC patients, the area under the ROC curve (AUC) of these three markers were all high. Multivariate analysis indicated that the location of the primary tumor, pathological differentiation, and pretreatment carcinoembryonic antigen (CEA), CRP, GPS, and CAR were independent prognostic factors for OS in stage I-III patients and that CRP, GPS, and CAR were independent prognostic factors for OS in CRLM patients. The predictors in the prediction nomograms included the pretreatment CRP, GPS, and CAR. Conclusions: CRP, GPS, and CAR have independent prognostic values in patients with CRC. Furthermore, the survival nomograms based on CRP, GPS, and CAR can provide more valuable clinical significance.
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Chemotherapy remains a powerful tool to eliminate malignant cells. However, the efficacy of chemotherapy is compromised by the frequent emergence of intrinsic and acquired multidrug resistance (MDR). These chemoresistance modalities are based on a multiplicity of molecular mechanisms of drug resistance, including : 1) Impaired drug uptake into cancer cells; 2) Increased expression of ATP-binding cassette efflux transporters; 3) Loss of function of pro-apoptotic factors; 4) Enhanced DNA repair capacity; 5) Qualitative or quantitative alterations of specific cellular targets; 6) Alterations that allow cancer cells to tolerate adverse or stressful conditions; 7) Increased biotransformation or metabolism of anticancer drugs to less active or completely inactive metabolites; and 8) Intracellular and intercellular drug sequestration in well-defined organelles away from the cellular target. Hence, one of the major aims of cancer research is to develop novel strategies to overcome cancer drug resistance. Over the last decades, nanomedicine, which focuses on targeted delivery of therapeutic drugs into tumor tissues using nano-sized formulations, has emerged as a promising tool for cancer treatment. Therefore, nanomedicine has been introduced as a reliable approach to improve treatment efficacy and minimize detrimental adverse effects as well as overcome cancer drug resistance. With rationally designed strategies including passively targeted delivery, actively targeted delivery, delivery of multidrug combinations, as well as multimodal combination therapy, nanomedicine paves the way towards efficacious cancer treatment and hold great promise in overcoming cancer drug resistance. Herein, we review the recent progress of nanomaterials used in medicine, including liposomal nanoparticles, polymeric nanoparticles, inorganic nanoparticles and hybrid nanoparticles, to surmount cancer multidrug resistance. Finally, the future perspectives of the application of nanomedicine to reverse cancer drug resistance will be addressed.
Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Nanomedicina , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismoRESUMO
The role of intestine clock in energy homeostasis remains elusive. Here we show that mice with Bmal1 specifically deleted in the intestine (Bmal1iKO mice) have a normal phenotype on a chow diet. However, on a high-fat diet (HFD), Bmal1iKO mice are protected against development of obesity and related abnormalities such as hyperlipidemia and fatty livers. These metabolic phenotypes are attributed to impaired lipid resynthesis in the intestine and reduced fat secretion. Consistently, wild-type mice fed a HFD during nighttime (with a lower BMAL1 expression) show alleviated obesity compared to mice fed ad libitum. Mechanistic studies uncover that BMAL1 transactivates the Dgat2 gene (encoding the triacylglycerol synthesis enzyme DGAT2) via direct binding to an E-box in the promoter, thereby promoting dietary fat absorption. Supporting these findings, intestinal deficiency of Rev-erbα, a known BMAL1 repressor, enhances dietary fat absorption and exacerbates HFD-induced obesity and comorbidities. Moreover, small-molecule targeting of REV-ERBα/BMAL1 by SR9009 ameliorates HFD-induced obesity in mice. Altogether, intestine clock functions as an accelerator in dietary fat absorption and targeting intestinal BMAL1 may be a promising approach for management of metabolic diseases induced by excess fat intake.
Assuntos
Fatores de Transcrição ARNTL/genética , Ritmo Circadiano/genética , Diacilglicerol O-Aciltransferase/genética , Fígado Gorduroso/genética , Hiperlipidemias/genética , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Obesidade/genética , Fatores de Transcrição ARNTL/deficiência , Animais , Diacilglicerol O-Aciltransferase/metabolismo , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Regulação da Expressão Gênica , Homeostase/efeitos dos fármacos , Homeostase/genética , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Hiperlipidemias/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/prevenção & controle , Regiões Promotoras Genéticas , Ligação Proteica , Pirrolidinas/farmacologia , Transdução de Sinais , Tiofenos/farmacologia , Triglicerídeos/biossínteseRESUMO
Bacterial ghosts (BGs) are empty cell envelopes possessing native extracellular structures without a cytoplasm and genetic materials. BGs are proposed to have significant prospects in biomedical research as vaccines or delivery carriers. The applications of BGs are often limited by inefficient bacterial lysis and a low yield. To solve these problems, we compared the lysis efficiency of the wild-type protein E (EW) from phage ΦX174 and the screened mutant protein E (EM) in the Escherichia coli BL21(DE3) strain. The results show that the lysis efficiency mediated by protein EM was improved. The implementation of the pLysS plasmid allowed nearly 100% lysis efficiency, with a high initial cell density as high as OD600 = 2.0, which was higher compared to the commonly used BG preparation method. The results of Western blot analysis and immunofluorescence indicate that the expression level of protein EM was significantly higher than that of the non-pLysS plasmid. High-quality BGs were observed by SEM and TEM. To verify the applicability of this method in other bacteria, the T7 RNA polymerase expression system was successfully constructed in Salmonella enterica (S. Enterica, SE). A pET vector containing EM and pLysS were introduced to obtain high-quality SE ghosts which could provide efficient protection for humans and animals. This paper describes a novel and commonly used method to produce high-quality BGs on a large scale for the first time.