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Acetylation of histone and nonhistone proteins is an important posttranslational modification affecting many cellular processes. Here, we report that NuA4 acetylation of Sip2, a regulatory ß subunit of the Snf1 complex (yeast AMP-activated protein kinase), decreases as cells age. Sip2 acetylation, controlled by antagonizing NuA4 acetyltransferase and Rpd3 deacetylase, enhances interaction with Snf1, the catalytic subunit of Snf1 complex. Sip2-Snf1 interaction inhibits Snf1 activity, thus decreasing phosphorylation of a downstream target, Sch9 (homolog of Akt/S6K), and ultimately leading to slower growth but extended replicative life span. Sip2 acetylation mimetics are more resistant to oxidative stress. We further demonstrate that the anti-aging effect of Sip2 acetylation is independent of extrinsic nutrient availability and TORC1 activity. We propose a protein acetylation-phosphorylation cascade that regulates Sch9 activity, controls intrinsic aging, and extends replicative life span in yeast.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/fisiologia , Transativadores/metabolismo , Acetilação , Restrição Calórica , Divisão Celular , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/enzimologia , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND & AIMS: Although the presence of tertiary lymphoid structures (TLS) correlates with positive responses to immunotherapy in many solid malignancies, the mechanism by which TLS enhances antitumor immunity is not well understood. The present study aimed to investigate the underlying cross talk circuits between B cells and tissue-resident memory T (Trm) cells within the TLS and to understand their role in the context of immunotherapy. METHODS: Immunostaining and H&E staining of TLS and chemokine (C-X-C motif) ligand 13 (CXCL13)+ cluster of differentiation (CD)103+CD8+ Trm cells were performed on tumor sections from patients with gastric cancer (GC). The mechanism of communication between B cells and CXCL13+CD103+CD8+ Trm cells was determined in vitro and in vivo. The effect of CXCL13+CD103+CD8+ Trm cells in suppressing tumor growth was evaluated through anti-programmed cell death protein (PD)-1 therapy. RESULTS: The presence of TLS and CXCL13+CD103+CD8+ Trm cells in tumor tissues favored a superior response to anti-PD-1 therapy in patients with GC. Additionally, our research identified that activated B cells enhanced CXCL13 and granzyme B secretion by CD103+CD8+ Trm cells. Mechanistically, B cells facilitated the glycolysis of CD103+CD8+ Trm cells through the lymphotoxin-α/tumor necrosis factor receptor 2 (TNFR2) axis, and the mechanistic target of rapamycin signaling pathway played a critical role in CD103+CD8+ Trm cells glycolysis during this process. Moreover, the presence of TLS and CXCL13+CD103+CD8+ Trm cells correlated with potent responsiveness to anti-PD-1 therapy in a TNFR2-dependent manner. CONCLUSIONS: This study further reveals a crucial role for cellular communication between TLS-associated B cell and CXCL13+CD103+CD8+ Trm cells in antitumor immunity, providing valuable insights into the potential use of the lymphotoxin-α/TNFR2 axis within CXCL13+CD103+CD8+ Trm cells for advancing immunotherapy strategies in GC.
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Antígenos CD , Linfócitos B , Linfócitos T CD8-Positivos , Quimiocina CXCL13 , Inibidores de Checkpoint Imunológico , Cadeias alfa de Integrinas , Células T de Memória , Receptor de Morte Celular Programada 1 , Neoplasias Gástricas , Estruturas Linfoides Terciárias , Quimiocina CXCL13/metabolismo , Humanos , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/efeitos dos fármacos , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Neoplasias Gástricas/tratamento farmacológico , Antígenos CD/metabolismo , Cadeias alfa de Integrinas/metabolismo , Cadeias alfa de Integrinas/imunologia , Células T de Memória/imunologia , Células T de Memória/metabolismo , Animais , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Granzimas/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Memória Imunológica , Transdução de Sinais/imunologia , Microambiente Tumoral/imunologia , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Camundongos , Imunoterapia/métodos , Linhagem Celular TumoralRESUMO
BACKGROUND & AIMS: Although the presence of tertiary lymphoid structures (TLS) correlates with positive responses to immunotherapy in many solid malignancies, the mechanism by which TLS enhances anti-tumor immunity is not well understood. The present study aimed to investigate the underlying cross-talk circuits between B cells and tissue-resident memory T (Trm) cells within the TLS and to understand their role in the context of immunotherapy. METHODS: Immunostaining and hematoxylin and eosin staining of TLS and CXCL13+CD103+CD8+Trm cells were performed on tumor sections from patients with gastric cancer (GC). The mechanism of communication between B cells and CXCL13+CD103+CD8+Trm cells was determined both in vitro and in vivo. The effect of CXCL13+CD103+CD8+Trm cells in suppressing tumor growth was evaluated through anti-PD-1 therapy. RESULTS: The presence of TLS and CXCL13+CD103+CD8+Trm cells in tumor tissues favored a superior response to anti-PD-1 therapy in GC patients. Additionally, our research identified that activated B cells enhanced CXCL13 and granzyme B secretion by CD103+CD8+Trm cells. Mechanistically, B cells facilitated the glycolysis of CD103+CD8+Trm cells through the Lymphotoxin Alpha (LTα)/Tumor necrosis factor receptor 2 (TNFR2) axis, and the mTOR signaling pathway played a critical role in CD103+CD8+Trm cells glycolysis during this process. Moreover, the presence of TLS and CXCL13+CD103+CD8+Trm cells correlated with potent responsiveness to anti-PD-1 therapy in a TNFR2 dependent manner. CONCLUSIONS: This study further reveals a crucial role for cellular communication between TLS-associated B cell and CXCL13+CD103+CD8+Trm cells in anti-tumor immunity, providing valuable insights into the potential utilization of the LTα/TNFR2 axis within CXCL13+CD103+CD8+Trm cells for advancing immunotherapy strategies in GC.
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BACKGROUND AND AIMS: Type 3 innate lymphoid cells (ILC3s) are essential for host defense against infection and tissue homeostasis. However, their role in the development of HCC has not been adequately confirmed. In this study, we investigated the immunomodulatory role of short-chain fatty acids (SCFAs) derived from intestinal microbiota in ILC3 regulation. APPROACH AND RESULTS: We report that Lactobacillus reuteri was markedly reduced in the gut microbiota of mice with HCC, accompanied by decreased SCFA levels, especially acetate. Additionally, transplantation of fecal bacteria from wild-type mice or L. reuteri could promote an anticancer effect, elevate acetate levels, and reduce IL-17A secretion in mice with HCC. Mechanistically, acetate reduced the production of IL-17A in hepatic ILC3s by inhibiting histone deacetylase activity, increasing the acetylation of SRY (sex-determining region Y)-box transcription factor 13 (Sox13) at site K30, and decreasing expression of Sox13. Moreover, the combination of acetate with programmed death 1/programmed death ligand 1 blockade significantly enhanced antitumor immunity. Consistently, tumor-infiltrating ILC3s correlated with negative prognosis in patients with HCC, which could be functionally mediated by acetate. CONCLUSIONS: These findings suggested that modifying bacteria, changing SCFAs, reducing IL-17A-producing ILC3 infiltration, and combining with immune checkpoint inhibitors will contribute to the clinical treatment of HCC.
Assuntos
Carcinoma Hepatocelular , Microbioma Gastrointestinal , Neoplasias Hepáticas , Camundongos , Animais , Interleucina-17 , Imunidade Inata , Carcinoma Hepatocelular/metabolismo , Linfócitos , Neoplasias Hepáticas/metabolismo , Ácidos Graxos Voláteis/metabolismo , AcetatosRESUMO
Mass spectrometry (MS) assays offer exceptional capabilities in high multiplexity, specificity, and throughput. As proteomics technologies continue advancements to identify new disease biomarkers, transition of these innovations from research settings to clinical applications becomes imperative. To meet the rigorous regulatory standards of clinical laboratories, development of a clinical protein MS assay necessitates adherence to stringent criteria. To illustrate the process, this project focused on using thyroglobulin (Tg) as a biomarker and an immuno-multiple reaction monitoring (iMRM) MS-based assay as a model for establishing a Clinical Laboratory Improvement Amendments (CLIA) compliant laboratory within the Centers of Genomic and Precision Medicine, National Taiwan University. The chosen example also illustrates the clinical utility of MS assays to complement conventional immunoassay-based methods, particularly in cases where the presence of autoantibodies in 10-30% of patients hinders accuracy. The laboratory design entails a comprehensive coordination in spatial layout, workflow organization, equipment selection, ventilation systems, plumbing, electrical infrastructure, documentation procedures, and communication protocols. Practical aspects of the transformation process, including preparing laboratory facilities, testing environments, instrument validation, assay development and validation, quality management, sample testing, and personnel competency, are discussed. Finally, concordant results in proficiency testing demonstrate the harmonization with the University of Washington Medical Center and the quality assurance of the CLIA-equivalent Tg-iMRM MS assay established in Taiwan. The realization of this model protein MS assay in Taiwan highlights the feasibility of international joint development and provides a detailed reference map to expedite the implementation of more MS-based protein assays in clinical laboratories for patient care.
RESUMO
Histone acetyltransferases (HATs) and histone deacetylases (HDACs) conduct many critical functions through nonhistone substrates in metazoans, but only chromatin-associated nonhistone substrates are known in Saccharomyces cerevisiae. Using yeast proteome microarrays, we identified and validated many nonchromatin substrates of the essential nucleosome acetyltransferase of H4 (NuA4) complex. Among these, acetylation sites (Lys19 and 514) of phosphoenolpyruvate carboxykinase (Pck1p) were determined by tandem mass spectrometry. Acetylation at Lys514 was crucial for enzymatic activity and the ability of yeast cells to grow on nonfermentable carbon sources. Furthermore, Sir2p deacetylated Pck1p both in vitro and in vivo. Loss of Pck1p activity blocked the extension of yeast chronological life span caused by water starvation. In human hepatocellular carcinoma (HepG2) cells, human Pck1 acetylation and glucose production were dependent on TIP60, the human homolog of ESA1. Our findings demonstrate a regulatory function for the NuA4 complex in glucose metabolism and life span by acetylating a critical metabolic enzyme.
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Gluconeogênese , Histona Acetiltransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetilação , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Histona Acetiltransferases/genética , Histona Desacetilases/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisina Acetiltransferase 5 , Complexos Multiproteicos/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Análise Serial de Proteínas , Sirtuínas/metabolismo , Água/metabolismoRESUMO
Anti-hypertensive medications may affect plasma renin activity and/or plasma aldosterone concentration, misleading the interpretation of the aldosterone-to-renin ratio when screening for primary aldosteronism. The Task Force of Taiwan PA recommends that, when necessary, using α-adrenergic receptor blocking agents, centrally acting α-adrenergic agonists, and/or non-dihydropyridine calcium channel blockers should be considered to control blood pressure before screening for PA. We recommend temporarily holding ß-adrenergic receptor blocking agents, mineralocorticoid receptor antagonists, dihydropyridine calcium channel blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and all diuretics before screening for PA. Further large-scale randomized controlled studies are required to confirm the recommendations.
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Hiperaldosteronismo , Hipertensão , Humanos , Anti-Hipertensivos/uso terapêutico , Aldosterona , Bloqueadores dos Canais de Cálcio/uso terapêutico , Renina , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/tratamento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapêuticoRESUMO
BACKGROUND AND AIMS: Innate lymphoid cells (ILCs) are tissue-resident lymphocytes that play critical roles in cytokine-mediated regulation of homeostasis and inflammation. However, relationships between their immune phenotypic characteristics and HCC remain largely unexplored. APPROACH AND RESULTS: We performed single-cell RNA sequencing analysis on sorted hepatic ILC cells from human patients with HCC and validated using flow cytometry, multiplex immunofluorescence staining, and functional experiments. Moreover, we applied selection strategies to enrich ILC populations in HCC samples to investigate the effects of B cells on the immune reaction of inducible T cell costimulator (ICOS)+ ILC2 cells. Dysregulation of ILCs was manifested by the changes in cell numbers or subset proportions in HCC. Seven subsets of 3433 ILCs were identified with unique properties, of which ICOS+ ILC2a were preferentially enriched in HCC and correlated with poor prognosis. Mechanistically, we report that B cells, particularly resting naïve B cells, have a previously unrecognized function that is involved in inflammatory differentiation of ILC2 cells. B cell-derived ICOSL signaling was responsible for exacerbating inflammation through the increased production of IL-13 in ICOS+ ILC2a cells. Heat shock protein 70 (HSP70) genes Heat Shock Protein Family A Member 1A (HSPA1A) and Heat Shock Protein Family A Member 1B (HSPA1B) were highly expressed in ILC2s in late-stage HCC, and targeting to ICOS and its downstream effector HSP70 in ILC2s suppressed tumor growth and remodeled the immunosuppressive tumor microenvironment. CONCLUSIONS: This in-depth understanding sheds light on B cell-driven innate type 2 inflammation and provides a potential strategy for HCC immunotherapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/metabolismo , Citocinas/metabolismo , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico , Humanos , Imunidade Inata , Inflamação/metabolismo , Interleucina-13/metabolismo , Neoplasias Hepáticas/metabolismo , Linfócitos , Fenótipo , Microambiente TumoralRESUMO
INTRODUCTION: Carnosine can suppress secondary complications in diabetes and show robust neuroprotective activity against neurodegenerative diseases. Here, we report that carnosine ameliorates diabetes-associated cognitive decline in vivo through the modulation of autophagy. METHODS: A high-fat diet (HFD) and one intraperitoneal injection of 30 mg/kg streptozotocin (STZ) were used to induce type 2 diabetes mellitus in Sprague-Dawley rats. The rats were randomly divided into five groups: control (CON), HFD/STZ, and three intragastric carnosine treatment groups receiving low (100 mg/kg), medium (300 mg/kg), and high (900 mg/kg) doses over 12 weeks. Body weight, blood glucose levels, and cognitive function were continuously monitored. From excised rat hippocampi, we determined superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels; carnosine concentration; protein expressions of Akt, mTOR and the autophagy markers LC3B and P62 and performed histopathological evaluations of the cornu ammonis 1 region. RESULTS: The HFD/STZ group showed increased blood glucose levels and decreased body weight compared to the CON group. However, there were no significant differences in body weight and blood glucose levels between carnosine-treated and -untreated HFD-STZ-induced diabetic rats. Diabetic animals showed obvious learning and memory impairments in the Morris water maze test compared to the CON group. Compared to those in the HFD/STZ group, carnosine increased SOD activity and decreased MDA levels, increased hippocampal carnosine concentration, increased p-Akt and p-mTOR expression, decreased LC3B and P62 expression, alleviated neuronal injuries, and improved cognitive performance in a dose-dependent manner. CONCLUSION: Independent of any hyperglycemic effect, carnosine may improve mild cognitive impairments by mitigating oxidative stress, activating the Akt/mTOR pathway, and modulating autophagy in the hippocampus of type 2 diabetic rats.
Assuntos
Carnosina , Disfunção Cognitiva , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Humanos , Ratos , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Carnosina/uso terapêutico , Carnosina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Glicemia , Ratos Sprague-Dawley , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/complicações , Serina-Treonina Quinases TOR/efeitos adversos , Superóxido Dismutase/efeitos adversos , Autofagia , Peso CorporalRESUMO
OBJECTIVE: Patients with Graves' disease who remain hyperthyroid under the treatment of antithyroid drugs (ATD) or cannot tolerate ATD usually receive radioactive iodine (RAI) to control disease activity. This pilot study aimed to identify predictors of prolonged euthyroidism > 12 months after receiving RAI. METHODS: Demographic, clinical, and laboratory data from 117 patients receiving RAI were retrospectively collected, including age, gender, body surface area, smoking status, free thyroxine, thyrotropin, thyrotropin binding inhibiting immunoglobulin, microsomal antibody, thyroglobulin antibody, medication history, and thyroid volume. Only 85 patients without missing values were included in statistical analysis. The calculated RAI dose was the estimated thyroid volume × 0.4. The difference and ratio between the actual and calculated RAI doses were examined. A stepwise logistic regression analysis was conducted to identify important predictors of prolonged euthyroidism > 12 months. The cut-off values for discretizing continuous covariates were estimated by fitting generalized additive models. RESULTS: Among the 85 patients on RAI, 18 (21.2%) achieved prolonged euthyroidism > 12 months, 38 (44.7%) remained hyperthyroid with decreased ATD doses, but 29 (34.1%) suffered permanent hypothyroidism and needed long-term levothyroxine. Logistic regression analysis revealed that patients with age > 66 years, 33 < age ≤ 66 years, quitting smoking vs nonsmoking or current smoking, 600 < micorsomal antibody ≤ 1729 IU/mL, 47% < thyrotropin binding inhibiting immunoglobulin ≤ 81%, 7 < thyroglobulin antibody ≤ 162 IU/mL, 0.63 < ratio between actual and calculated RAI doses ≤ 1.96, or taking hydroxychloroquine would have a higher chance of reaching prolonged euthyroidism > 12 months after receiving RAI. Its area under the Receiver Operating Characteristic (ROC) curve was 0.932. CONCLUSION: Patients with Graves' disease who received an actual RAI dose close to the calculated RAI dose achieved prolonged euthyroidism > 12 months if they also took hydroxychloroquine during RAI treatment.
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Doença de Graves , Hipertireoidismo , Iodo , Neoplasias da Glândula Tireoide , Humanos , Pré-Escolar , Radioisótopos do Iodo/uso terapêutico , Projetos Piloto , Tireoglobulina , Estudos Retrospectivos , Hidroxicloroquina/uso terapêutico , Doença de Graves/tratamento farmacológico , Doença de Graves/radioterapia , Hipertireoidismo/tratamento farmacológico , Antitireóideos/uso terapêutico , TireotropinaRESUMO
OBJECTIVE: Patients with increased PD-L1+ host cells in tumours are more potent to benefit from antiprogrammed death-1/programmed death ligand-1 (PD-L1) treatment, but the underlying mechanism is still unclear. We aim to elucidate the nature, regulation and functional relevance of PD-L1+ host cells in hepatocellular carcinoma (HCC). DESIGN: A total of untreated 184 HCC patients was enrolled randomly. C57BL/6 mice are given injection of Hepa1-6 cells to form autologous hepatoma. ELISpot, flow cytometry and real-time PCR are applied to analyse the phenotypic characteristics of PD-L1+ cells isolated directly from HCC specimens paired with blood samples or generated from ex vivo and in vitro culture systems. Immunofluorescence and immunohistochemistry are performed to detect the presence of immune cells on paraffin-embedded and formalin-fixed samples. The underlying regulatory mechanisms of metabolic switching are assessed by both in vitro and in vivo studies. RESULTS: We demonstrate that PD-L1+ host macrophages, which constructively represent the major cellular source of PD-L1 in HCC tumours, display an HLA-DRhighCD86high glycolytic phenotype, significantly produce antitumourigenic IL-12p70 and are polarised by intrinsic glycolytic metabolism. Mechanistically, a key glycolytic enzyme PKM2 triggered by hepatoma cell derived fibronectin 1, via a HIF-1α-dependent manner, concurrently controls the antitumourigenic properties and inflammation-mediated PD-L1 expression in glycolytic macrophages. Importantly, although increased PKM2+ glycolytic macrophages predict poor prognosis of patients, blocking PD-L1 on these cells eliminates PD-L1-dominant immunosuppression and liberates intrinsic antitumourigenic properties. CONCLUSIONS: Selectively modulating the 'context' of glycolytic macrophages in HCC tumours might restore their antitumourigenic properties and provide a precise strategy for anticancer therapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/metabolismo , Antígeno B7-H1/metabolismo , Neoplasias Hepáticas/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , MacrófagosRESUMO
Immune checkpoint blockade-based immunotherapy is a new modality of cancer treatment with a unique mechanism that has gained increased numbers of indication and is now used in several cancer types. However, immune-related adverse events (irAEs) emerge as a new entity of diseases involving one or multiple organ systems. irAEs could result in interruption of immunotherapy, morbidities or even death. Among various manifestations of irAEs, immune-mediated hypophysitis is rare but important, requiring prompt diagnosis and treatment to avoid life-threatening conditions. We report seven cases of immune-mediated hypophysitis in Taiwan. They suffered from various types of advanced cancer and received different regimens of immune checkpoint inhibitors. The time of onset after initiation of immunotherapy ranged from 5 to 36 weeks. All seven subjects were diagnosed of central adrenal insufficiency, while four of them had primary hypothyroidism. There was no typical finding of infiltrative hypophysitis on the pituitary MRI. There was no documented hormone recovery after diagnosis of hypophysitis, and the tumor responses to immunotherapy were variable in these seven patients. In conclusion, immune-mediated hypophysitis is often irreversible. Fortunately, it can be managed adequately with hormone replacements. Further investigations are warranted to unveil underlying mechanisms and ethnic differences to guide the solutions.
Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Hipofisite/induzido quimicamente , Neoplasias/terapia , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Doenças do Sistema Endócrino/induzido quimicamente , Feminino , Humanos , Imunoterapia/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , TaiwanRESUMO
First identified as histone-modifying proteins, lysine acetyltransferases (KATs) and deacetylases (KDACs) antagonize each other through modification of the side chains of lysine residues in histone proteins. Acetylation of many non-histone proteins involved in chromatin, metabolism or cytoskeleton regulation were further identified in eukaryotic organisms, but the corresponding enzymes and substrate-specific functions of the modifications are unclear. Moreover, mechanisms underlying functional specificity of individual KDACs remain enigmatic, and the substrate spectra of each KDAC lack comprehensive definition. Here we dissect the functional specificity of 12 critical human KDACs using a genome-wide synthetic lethality screen in cultured human cells. The genetic interaction profiles revealed enzyme-substrate relationships between individual KDACs and many important substrates governing a wide array of biological processes including metabolism, development and cell cycle progression. We further confirmed that acetylation and deacetylation of the catalytic subunit of the adenosine monophosphate-activated protein kinase (AMPK), a critical cellular energy-sensing protein kinase complex, is controlled by the opposing catalytic activities of HDAC1 and p300. Deacetylation of AMPK enhances physical interaction with the upstream kinase LKB1, leading to AMPK phosphorylation and activation, and resulting in lipid breakdown in human liver cells. These findings provide new insights into previously underappreciated metabolic regulatory roles of HDAC1 in coordinating nutrient availability and cellular responses upstream of AMPK, and demonstrate the importance of high-throughput genetic interaction profiling to elucidate functional specificity and critical substrates of individual human KDACs potentially valuable for therapeutic applications.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Histona Desacetilase 1/metabolismo , Lisina/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/química , Proteínas Quinases Ativadas por AMP/genética , Acetilação , Biocatálise , Domínio Catalítico , Ciclo Celular , Linhagem Celular , Linhagem Celular Tumoral , Histona Desacetilase 1/genética , Humanos , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Especificidade por Substrato , Fatores de Transcrição de p300-CBP/genéticaRESUMO
BACKGROUND/PURPOSE: Surgery followed by radioiodine is a mainstay of treatment for thyroid cancers of follicular origins. However, about 5% of the thyroid cancers are non-operable and/or radioiodine-refractory diseases, which are either locally advanced or metastatic and result in a survival of less than 5 years. How to treat this population of thyroid cancer patients becomes a critical issue requiring further understanding of the tumor's genetic information. METHODS: We used formalin-fixed paraffin-embedded specimens of 22 fatal thyroid cancers and their corresponding non-tumor parts, if available, to yield genomic DNA, and applied the Ion Torrent™ Personal Genome Machine (IT-PGM) System (Life Technologies), a next generation sequencing technology, to interrogate 740 mutational hotspots in 46 oncogenes. We further validated the results by conventional direct sequencing. RESULTS: We confirmed 21 mutations of 11 oncogenes in the 22 fatal thyroid cancer samples. Among them, the MET p.N375S and MLH1 p.V384D mutations, each was detected in two cases, and has rarely been found to be involved in thyroid cancer pathogenesis before. We also identified homozygous PDGFRA p.V824V mutation in eight out of the 22 cases, while the non-tumor counterparts carried heterozygous PDGFRA p.V824V mutation. We noted that the Ion Torrent technique unfortunately showed high false positive rates for detecting EGFR mutations in thyroid cancers. CONCLUSION: The extensive genetic studies provide new insights to future targeted therapy in these patients. IT-PGM proved to be valuable for comprehensively searching genetic mutations in potentially fatal thyroid cancers.
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Carcinoma/genética , Análise Mutacional de DNA/métodos , Mutação , Neoplasias da Glândula Tireoide/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Morte , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Taiwan , Neoplasias da Glândula Tireoide/patologiaRESUMO
Fluorescent liposomal nanovesicles (liposomes) are commonly used for lipid research and/or signal enhancement. However, the problem of self-quenching with conventional fluorescent liposomes limits their applications because these liposomes must be lysed to detect the fluorescent signals. Here, we developed a nonquenched fluorescent (NQF)1 liposome by optimizing the proportion of sulforhodamine B (SRB) encapsulant and lissamine rhodamine B-dipalmitoyl phosphatidylethanol (LRB-DPPE) on a liposomal surface for signal amplification. Our study showed that 0.3% of LRB-DPPE with 200 µm of SRB provided the maximal fluorescent signal without the need to lyse the liposomes. We also observed that the NQF liposomes largely eliminated self-quenching effects and produced greatly enhanced signals than SRB-only liposomes by 5.3-fold. To show their application in proteomics research, we constructed NQF liposomes that contained phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) and profiled its protein interactome using a yeast proteome microarray. Our profiling led to the identification of 162 PI(3,5)P2-specific binding proteins (PI(3,5)P2-BPs). We not only recovered many proteins that possessed known PI(3,5)P2-binding domains, but we also found two unknown Pfam domains (Pfam-B_8509 and Pfam-B_10446) that were enriched in our dataset. The validation of many newly discovered PI(3,5)P2-BPs was performed using a bead-based affinity assay. Further bioinformatics analyses revealed that the functional roles of 22 PI(3,5)P2-BPs were similar to those associated with PI(3,5)P2, including vesicle-mediated transport, GTPase, cytoskeleton, and kinase. Among the 162 PI(3,5)P2-BPs, we found a novel motif, HRDIKP[ES]NJLL that showed statistical significance. A docking simulation showed that PI(3,5)P2 interacted primarily with lysine or arginine side chains of the newly identified PI(3,5)P2-binding kinases. Our study showed that this new tool would greatly benefit profiling lipid-protein interactions in high-throughput studies.
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Metabolismo dos Lipídeos , Lipossomos/metabolismo , Nanopartículas/química , Análise Serial de Proteínas/métodos , Proteoma/metabolismo , Proteômica/métodos , Proteínas de Saccharomyces cerevisiae/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Cromatografia de Afinidade , Biologia Computacional , Citoesqueleto/metabolismo , Fluorescência , GTP Fosfo-Hidrolases/metabolismo , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Fosfatos de Fosfatidilinositol/metabolismo , Ligação Proteica , Transporte Proteico , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/metabolismo , Vesículas Transportadoras/metabolismoRESUMO
Asymmetric phase-transfer alkylation of the N-(arylmethylene)-α-alkylamino acid ethyl esters and N-(arylmethylene)glycine ethyl esters was found to be catalyzed by the (R)- or (S)-Simplified Maruoka Catalyst with high efficiency and excellent enantioselectivity. This approach was successfully applied to the enantioselective formal synthesis of the angiotensin II type 2 receptor (AT2R) antagonists Olodanrigan and LX9211, and the practical aspect is demonstrated by the kilogram-scale synthesis of a key intermediate for the synthesis of LX9211.
RESUMO
BACKGROUND: Osteoarthritis (OA) is a common degenerative joint disease characterized by persistent articular cartilage degeneration and synovitis. Oxymatrine (OMT) is a quinzolazine alkaloid extracted from the traditional Chinese medicine, matrine, and possesses anti-inflammatory properties that may help regulate the pathogenesis of OA; however, its mechanism has not been elucidated. This study aimed to investigate the effects of OMT on interleukin-1ß (IL-1ß)-induced damage and the potential mechanisms of action. METHODS: Chondrocytes were isolated from Sprague-Dawley rats. Toluidine blue and Collagen II immunofluorescence staining were used to determine the purity of the chondrocytes. Thereafter, the chondrocytes were subjected to IL-1ß stimulation, both in the presence and absence of OMT, or the autophagy inhibitor 3-methyladenine (3-MA). Cell viability was assessed using the MTT assay and SYTOX Green staining. Additionally, flow cytometry was used to determine cell apoptosis rate and reactive oxygen species (ROS) levels. The protein levels of AKT, mTOR, LC3, P62, matrix metalloproteinase-13, and collagen II were quantitatively analyzed using western blotting. Immunofluorescence was used to assess LC3 expression. RESULTS: OMT alleviated IL-1ß-induced damage in chondrocytes, by increasing the survival rate, reducing the apoptosis rates of chondrocytes, and preventing the degradation of the cartilage matrix. In addition, OMT decreased the ROS levels and inhibited the AKT/mTOR signaling pathway while promoting autophagy in IL-1ß treated chondrocytes. However, the effectiveness of OMT in improving chondrocyte viability under IL-1ß treatment was limited when autophagy was inhibited by 3-MA. CONCLUSIONS: OMT decreases oxidative stress and inhibits the AKT/mTOR signaling pathway to enhance autophagy, thus inhibiting IL-1ß-induced damage. Therefore, OMT may be a novel and effective therapeutic agent for the clinical treatment of OA.
Assuntos
Alcaloides , Cartilagem Articular , Matrinas , Osteoartrite , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Condrócitos/metabolismo , Interleucina-1beta/toxicidade , Interleucina-1beta/metabolismo , Osteoartrite/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Cartilagem Articular/metabolismo , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Alcaloides/metabolismo , Autofagia , Colágeno/metabolismo , ApoptoseRESUMO
Tumor recurrence is an important factor indicative of a poor prognosis in glioblastoma (GBM). Many studies are attempting to identify effective therapeutic strategies to prevent the recurrence of GBM after surgery. Bioresponsive therapeutic hydrogels capable of sustaining locally released drugs are frequently used for the local treatment of GBM after surgery. However, research is limited due to the lack of a suitable GBM relapse post-resection model. Here, a GBM relapse post-resection model was developed and applied in therapeutic hydrogel investigations. This model was constructed based on the orthotopic intracranial GBM model, which is widely used in studies on GBM. Subtotal resection was performed on the orthotopic intracranial GBM model mouse to mimic the clinical treatment. The residual tumor was used to indicate the size of the tumor growth. This model is easy to build, can better mimic the situation of GBM surgical resection, and can be applied in various studies on the local treatment of GBM relapse post-resection. As a result, the GBM relapse post-resection model provides a unique GBM recurrence model for effective local treatment studies of relapse post-resection.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Camundongos , Animais , Glioblastoma/patologia , Hidrogéis/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Encefálicas/patologia , Doença Crônica , RecidivaRESUMO
BACKGROUND: Immune-checkpoint inhibitors (ICIs) remain ineffective in a large group of non-small cell lung cancer (NSCLC) patients. Mucosal-associated invariant T (MAIT) cells, a population of unconventional innate-like T lymphocytes abundant in the human body, play important roles in human malignancies. Little is known about the immune characteristics of MAIT cells in NSCLC and correlation with prognosis and response rate of ICIs treatment. METHODS: To investigate the distribution, activation status, and function of MAIT cells in NSCLC patients and their correlations with anti-PD-1 immunotherapy, MAIT cells in peripheral blood, tumor and paratumor samples from NSCLC patients with or without anti-PD-1 immunotherapy were analyzed using flow cytometry and single-cell RNA-sequencing. RESULTS: MAIT cells were enriched in the tumor lesions of NSCLC patients migrating from peripheral blood via the CCR6-CCL20 axis. Both peripheral and tumor-infiltrating MAIT cells displayed an exhausted phenotype with upregulated PD-1, TIM-3, and IL-17A while less IFN-γ. Anti-PD-1 therapy reversed the function of circulating MAIT cells with higher expression of IFN-γ and granzyme B. Subcluster MAIT-17s (defined as cells highly expressing exhausted and Th17-related genes) mainly infiltrated in the non-responsive tissues, while the subcluster MAIT-IFNGRs (cells expressing genes related to cytotoxic function) were mainly enriched in responsive tissues. Moreover, we found predictive value of circulating MAIT cells for anti-PD-1 immunotherapy in NSCLC patients. CONCLUSIONS: MAIT cells shifted to an exhausted tumor-promoting phenotype in NSCLC patients and the circulating MAIT subset could be a predictor for patients who respond to anti-PD-1 immunotherapy.