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1.
Cell ; 182(3): 713-721.e9, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32778225

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health. The development of a vaccine is urgently needed for the prevention and control of COVID-19. Here, we report the pilot-scale production of an inactivated SARS-CoV-2 vaccine candidate (BBIBP-CorV) that induces high levels of neutralizing antibodies titers in mice, rats, guinea pigs, rabbits, and nonhuman primates (cynomolgus monkeys and rhesus macaques) to provide protection against SARS-CoV-2. Two-dose immunizations using 2 µg/dose of BBIBP-CorV provided highly efficient protection against SARS-CoV-2 intratracheal challenge in rhesus macaques, without detectable antibody-dependent enhancement of infection. In addition, BBIBP-CorV exhibits efficient productivity and good genetic stability for vaccine manufacture. These results support the further evaluation of BBIBP-CorV in a clinical trial.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Avaliação Pré-Clínica de Medicamentos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas de Produtos Inativados/uso terapêutico , Vacinas Virais/uso terapêutico , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/genética , COVID-19 , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Feminino , Cobaias , Imunogenicidade da Vacina , Macaca fascicularis , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Pneumonia Viral/virologia , Coelhos , Ratos , Ratos Wistar , SARS-CoV-2 , Vacinas de Produtos Inativados/efeitos adversos , Células Vero , Vacinas Virais/efeitos adversos
2.
Cell ; 176(3): 535-548.e24, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30661751

RESUMO

The splicing of pre-mRNAs into mature transcripts is remarkable for its precision, but the mechanisms by which the cellular machinery achieves such specificity are incompletely understood. Here, we describe a deep neural network that accurately predicts splice junctions from an arbitrary pre-mRNA transcript sequence, enabling precise prediction of noncoding genetic variants that cause cryptic splicing. Synonymous and intronic mutations with predicted splice-altering consequence validate at a high rate on RNA-seq and are strongly deleterious in the human population. De novo mutations with predicted splice-altering consequence are significantly enriched in patients with autism and intellectual disability compared to healthy controls and validate against RNA-seq in 21 out of 28 of these patients. We estimate that 9%-11% of pathogenic mutations in patients with rare genetic disorders are caused by this previously underappreciated class of disease variation.


Assuntos
Previsões/métodos , Precursores de RNA/genética , Splicing de RNA/genética , Algoritmos , Processamento Alternativo/genética , Transtorno Autístico/genética , Aprendizado Profundo , Éxons/genética , Humanos , Deficiência Intelectual/genética , Íntrons/genética , Redes Neurais de Computação , Precursores de RNA/metabolismo , Sítios de Splice de RNA/genética , Sítios de Splice de RNA/fisiologia
3.
Nature ; 625(7996): 735-742, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030727

RESUMO

Noncoding DNA is central to our understanding of human gene regulation and complex diseases1,2, and measuring the evolutionary sequence constraint can establish the functional relevance of putative regulatory elements in the human genome3-9. Identifying the genomic elements that have become constrained specifically in primates has been hampered by the faster evolution of noncoding DNA compared to protein-coding DNA10, the relatively short timescales separating primate species11, and the previously limited availability of whole-genome sequences12. Here we construct a whole-genome alignment of 239 species, representing nearly half of all extant species in the primate order. Using this resource, we identified human regulatory elements that are under selective constraint across primates and other mammals at a 5% false discovery rate. We detected 111,318 DNase I hypersensitivity sites and 267,410 transcription factor binding sites that are constrained specifically in primates but not across other placental mammals and validate their cis-regulatory effects on gene expression. These regulatory elements are enriched for human genetic variants that affect gene expression and complex traits and diseases. Our results highlight the important role of recent evolution in regulatory sequence elements differentiating primates, including humans, from other placental mammals.


Assuntos
Sequência Conservada , Evolução Molecular , Genoma , Primatas , Animais , Feminino , Humanos , Gravidez , Sequência Conservada/genética , Desoxirribonuclease I/metabolismo , DNA/genética , DNA/metabolismo , Genoma/genética , Mamíferos/classificação , Mamíferos/genética , Placenta , Primatas/classificação , Primatas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/metabolismo , Proteínas/genética , Regulação da Expressão Gênica/genética
4.
Nature ; 606(7916): 890-895, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35676489

RESUMO

Majorana zero modes (MZMs) obey non-Abelian statistics and are considered building blocks for constructing topological qubits1,2. Iron-based superconductors with topological bandstructures have emerged as promising hosting materials, because isolated candidate MZMs in the quantum limit have been observed inside the topological vortex cores3-9. However, these materials suffer from issues related to alloying induced disorder, uncontrolled vortex lattices10-13 and a low yield of topological vortices5-8. Here we report the formation of an ordered and tunable MZM lattice in naturally strained stoichiometric LiFeAs by scanning tunnelling microscopy/spectroscopy. We observe biaxial charge density wave (CDW) stripes along the Fe-Fe and As-As directions in the strained regions. The vortices are pinned on the CDW stripes in the As-As direction and form an ordered lattice. We detect that more than 90 per cent of the vortices are topological and possess the characteristics of isolated MZMs at the vortex centre, forming an ordered MZM lattice with the density and the geometry tunable by an external magnetic field. Notably, with decreasing the spacing of neighbouring vortices, the MZMs start to couple with each other. Our findings provide a pathway towards tunable and ordered MZM lattices as a platform for future topological quantum computation.

5.
Nature ; 599(7884): 222-228, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34587621

RESUMO

The transition metal kagome lattice materials host frustrated, correlated and topological quantum states of matter1-9. Recently, a new family of vanadium-based kagome metals, AV3Sb5 (A = K, Rb or Cs), with topological band structures has been discovered10,11. These layered compounds are nonmagnetic and undergo charge density wave transitions before developing superconductivity at low temperatures11-19. Here we report the observation of unconventional superconductivity and a pair density wave (PDW) in CsV3Sb5 using scanning tunnelling microscope/spectroscopy and Josephson scanning tunnelling spectroscopy. We find that CsV3Sb5 exhibits a V-shaped pairing gap Δ ~ 0.5 meV and is a strong-coupling superconductor (2Δ/kBTc ~ 5) that coexists with 4a0 unidirectional and 2a0 × 2a0 charge order. Remarkably, we discover a 3Q PDW accompanied by bidirectional 4a0/3 spatial modulations of the superconducting gap, coherence peak and gap depth in the tunnelling conductance. We term this novel quantum state a roton PDW associated with an underlying vortex-antivortex lattice that can account for the observed conductance modulations. Probing the electronic states in the vortex halo in an applied magnetic field, in strong field that suppresses superconductivity and in zero field above Tc, reveals that the PDW is a primary state responsible for an emergent pseudogap and intertwined electronic order. Our findings show striking analogies and distinctions to the phenomenology of high-Tc cuprate superconductors, and provide groundwork for understanding the microscopic origin of correlated electronic states and superconductivity in vanadium-based kagome metals.

6.
Mol Cell ; 76(1): 148-162.e7, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31447391

RESUMO

The rapid proliferation of cancer cells and dysregulated vasculature within the tumor leads to limited nutrient accessibility. Cancer cells often rewire their metabolic pathways for adaption to nutrient stress, and the underlying mechanism remains largely unknown. Glutamate dehydrogenase 1 (GDH1) is a key enzyme in glutaminolysis that converts glutamate to α-ketoglutarate (α-KG). Here, we show that, under low glucose, GDH1 is phosphorylated at serine (S) 384 and interacts with RelA and IKKß. GDH1-produced α-KG directly binds to and activates IKKß and nuclear factor κB (NF-κB) signaling, which promotes glucose uptake and tumor cell survival by upregulating GLUT1, thereby accelerating gliomagenesis. In addition, GDH1 S384 phosphorylation correlates with the malignancy and prognosis of human glioblastoma. Our finding reveals a unique role of α-KG to directly regulate signal pathway, uncovers a distinct mechanism of metabolite-mediated NF-κB activation, and also establishes the critical role of α-KG-activated NF-κB in brain tumor development.


Assuntos
Neoplasias Encefálicas/metabolismo , Proliferação de Células , Metabolismo Energético , Glioblastoma/metabolismo , Glucose/metabolismo , Glutamato Desidrogenase/metabolismo , Ácidos Cetoglutáricos/metabolismo , NF-kappa B/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Criança , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Glucose/deficiência , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Glutamato Desidrogenase/genética , Células HEK293 , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , NF-kappa B/genética , Gradação de Tumores , Fosforilação , Transdução de Sinais , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Adulto Jovem
7.
Blood ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848533

RESUMO

The liver plays a crucial role in maintaining systemic iron homeostasis by secreting hepcidin, which is essential for coordinating iron levels in the body. Imbalances in iron homeostasis are associated with various clinical disorders related to iron deficiency or iron overload. Despite the clinical significance, the mechanisms underlying how hepatocytes sense extracellular iron levels to regulate hepcidin synthesis and iron storage are not fully understood. In this study, we identified Foxo1, a well-known regulator of macronutrient metabolism, that translocates to the nucleus of hepatocytes in response to high-iron feeding, holo-transferrin, and BMP6 treatment. Furthermore, Foxo1 plays a crucial role in mediating hepcidin induction in response to both iron and BMP signals by directly interacting with evolutionally conserved Foxo binding sites within the hepcidin promoter region. These binding sites were found to colocalize with Smad-binding sites. To investigate the physiological relevance of Foxo1 in iron metabolism, we generated mice with hepatocyte-specific deletion of Foxo1. These mice exhibited reduced hepatic hepcidin expression and serum hepcidin levels, accompanied by elevated serum iron and liver non-heme iron concentrations. Moreover, high-iron diet further exacerbated these abnormalities in iron metabolism in mice lacking hepatic Foxo1. Conversely, hepatocyte-specific Foxo1 overexpression increased hepatic hepcidin expression and serum hepcidin levels, thereby ameliorating iron overload in a murine model of hereditary hemochromatosis (Hfe-/- mice). In summary, our study identifies Foxo1 is a critical regulator of hepcidin and systemic iron homeostasis. Targeting Foxo1 may offer therapeutic opportunities for managing conditions associated with aberrant iron metabolism.

8.
Nature ; 586(7830): 572-577, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32726802

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a respiratory disease called coronavirus disease 2019 (COVID-19), the spread of which has led to a pandemic. An effective preventive vaccine against this virus is urgently needed. As an essential step during infection, SARS-CoV-2 uses the receptor-binding domain (RBD) of the spike protein to engage with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells1,2. Here we show that a recombinant vaccine that comprises residues 319-545 of the RBD of the spike protein induces a potent functional antibody response in immunized mice, rabbits and non-human primates (Macaca mulatta) as early as 7 or 14 days after the injection of a single vaccine dose. The sera from the immunized animals blocked the binding of the RBD to ACE2, which is expressed on the cell surface, and neutralized infection with a SARS-CoV-2 pseudovirus and live SARS-CoV-2 in vitro. Notably, vaccination also provided protection in non-human primates to an in vivo challenge with SARS-CoV-2. We found increased levels of RBD-specific antibodies in the sera of patients with COVID-19. We show that several immune pathways and CD4 T lymphocytes are involved in the induction of the vaccine antibody response. Our findings highlight the importance of the RBD domain in the design of SARS-CoV-2 vaccines and provide a rationale for the development of a protective vaccine through the induction of antibodies against the RBD domain.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , COVID-19 , Vacinas contra COVID-19 , Humanos , Macaca mulatta/imunologia , Macaca mulatta/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais , Modelos Moleculares , Domínios Proteicos , SARS-CoV-2 , Soro/imunologia , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Vacinação
9.
Nature ; 583(7818): 830-833, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380511

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Pulmão/patologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Transgenes , Enzima de Conversão de Angiotensina 2 , Animais , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Betacoronavirus/imunologia , Betacoronavirus/metabolismo , Brônquios/patologia , Brônquios/virologia , COVID-19 , Infecções por Coronavirus/imunologia , Modelos Animais de Doenças , Células Epiteliais/patologia , Células Epiteliais/virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Pulmão/imunologia , Pulmão/virologia , Linfócitos/imunologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/virologia , Masculino , Camundongos , Camundongos Transgênicos , Pandemias , Pneumonia Viral/imunologia , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/metabolismo , SARS-CoV-2 , Replicação Viral , Redução de Peso
10.
Mol Cell ; 71(2): 201-215.e7, 2018 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-30029001

RESUMO

Macrophages are a dominant leukocyte population in the tumor microenvironment and actively promote cancer progression. However, the molecular mechanism underlying the role of macrophages remains poorly understood. Here we show that polarized M2 macrophages enhance 3-phosphoinositide-dependent protein kinase 1 (PDPK1)-mediated phosphoglycerate kinase 1 (PGK1) threonine (T) 243 phosphorylation in tumor cells by secreting interleukin-6 (IL-6). This phosphorylation facilitates a PGK1-catalyzed reaction toward glycolysis by altering substrate affinity. Inhibition of PGK1 T243 phosphorylation or PDPK1 in tumor cells or neutralization of macrophage-derived IL-6 abrogates macrophage-promoted glycolysis, proliferation, and tumorigenesis. In addition, PGK1 T243 phosphorylation correlates with PDPK1 activation, IL-6 expression, and macrophage infiltration in human glioblastoma multiforme (GBM). Moreover, PGK1 T243 phosphorylation also correlates with malignance and prognosis of human GBM. Our findings demonstrate a novel mechanism of macrophage-promoted tumor growth by regulating tumor cell metabolism, implicating the therapeutic potential to disrupt the connection between macrophages and tumor cells by inhibiting PGK1 phosphorylation.


Assuntos
Macrófagos/metabolismo , Fosfoglicerato Quinase/genética , Fosfoglicerato Quinase/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/genética , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Glicólise , Humanos , Macrófagos/patologia , Camundongos , Camundongos Nus , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Fosforilação , Prognóstico , Microambiente Tumoral
11.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37537355

RESUMO

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

12.
Hepatology ; 80(2): 363-375, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38456794

RESUMO

BACKGROUND AND AIMS: In obesity, depletion of KCs expressing CRIg (complement receptor of the Ig superfamily) leads to microbial DNA accumulation, which subsequently triggers tissue inflammation and insulin resistance. However, the mechanism underlying obesity-mediated changes in KC complement immune functions is largely unknown. APPROACH AND RESULTS: Using KC-specific deactivated Cas9 transgenic mice treated with guide RNA, we assessed the effects of restoring CRIg or the serine/arginine-rich splicing factor 3 (SRSF3) abundance on KC functions and metabolic phenotypes in obese mice. The impacts of weight loss on KC responses were evaluated in a diet switch mouse model. The role of SRSF3 in regulating KC functions was also evaluated using KC-specific SRSF3 knockout mice. Here, we report that overexpression of CRIg in KCs of obese mice protects against bacterial DNA accumulation in metabolic tissues. Mechanistically, SRSF3 regulates CRIg expression, which is essential for maintaining the CRIg+ KC population. During obesity, SRSF3 expression decreases, but it is restored with weight loss through a diet switch, normalizing CRIg+ KCs. KC SRSF3 is also repressed in obese human livers. Lack of SRSF3 in KCs in lean and obese mice decreases their CRIg+ population, impairing metabolic parameters. During the diet switch, the benefits of weight loss are compromised due to SRSF3 deficiency. Conversely, SRSF3 overexpression in obese mice preserves CRIg+ KCs and improves metabolic responses. CONCLUSIONS: Restoring SRSF3 abundance in KCs offers a strategy against obesity-associated tissue inflammation and insulin resistance by preventing bacterial DNA accumulation.


Assuntos
Resistência à Insulina , Células de Kupffer , Obesidade , Fatores de Processamento de Serina-Arginina , Animais , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Obesidade/metabolismo , Camundongos , Células de Kupffer/metabolismo , Humanos , Masculino , Camundongos Transgênicos , Camundongos Knockout , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
13.
Exp Cell Res ; 435(2): 113937, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38242344

RESUMO

Lung carcinoma (LC) is a complicated and highly heterogeneous disease with high morbidity and mortality. Both lysyl oxidase-like (LOXL) 2 and 3 act in cancer progression. This work endeavors to illustrate the influence of LOXL2/LOXL3 on LC progression and the underlying mechanisms. LOXL family genes and CCAAT enhancer binding protein A (CEBPA) were analyzed in the TCGA database for their expression patterns in LC patients and their correlations with the patient's prognosis. CEBPA, LOXL2, and LOXL3 expression levels were determined in LC cells. Gain- and loss-of-function assays were conducted, followed by assays for cell proliferation, epithelial-mesenchymal transition (EMT), apoptosis, invasion, and migration. The binding of CEBPA or B cell lymphoma protein (BCL)-2 to LOXL2/LOXL3 was verified. The ubiquitination level of BCL-2 and histone acetylation level of LOXL2/LOXL3 in LC cells were analyzed. Database analyses revealed that LC patients had high CEBPA, LOXL2, and LOXL3 expression, which were related to poor prognosis. LC cells also exhibited high CEBPA, LOXL2, and LOXL3 levels. LOXL2/LOXL3 knockdown subdued EMT, proliferation, migration, and invasion while enhancing the apoptosis of LC cells. LOXL2/LOXL3 could bind to CEBPA and BCL-2. LOXL2/LOXL3 knockdown upregulated BCL-2 ubiquitination level and diminished BCL-2 expression in LC cells. CEBPA recruited Tip60 to enhance histone acetylation and transcription of LOXL2/LOXL3 in LC cells. BCL-2 overexpression abolished the impacts of LOXL2/LOXL3 knockdown on LC cells. In conclusion, CEBPA boosts LOXL2 and LOXL3 transcription to facilitate BCL-2 stability by recruiting Tip60 and thus contributes to LC cell growth and metastasis.


Assuntos
Carcinoma , Neoplasias Pulmonares , Humanos , Histonas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Pulmão/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Aminoácido Oxirredutases/genética , Proteínas Estimuladoras de Ligação a CCAAT
14.
Nature ; 571(7763): 127-131, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31243371

RESUMO

Cancer metastasis is the primary cause of morbidity and mortality, and accounts for up to 95% of cancer-related deaths1. Cancer cells often reprogram their metabolism to efficiently support cell proliferation and survival2,3. However, whether and how those metabolic alterations contribute to the migration of tumour cells remain largely unknown. UDP-glucose 6-dehydrogenase (UGDH) is a key enzyme in the uronic acid pathway, and converts UDP-glucose to UDP-glucuronic acid4. Here we show that, after activation of EGFR, UGDH is phosphorylated at tyrosine 473 in human lung cancer cells. Phosphorylated UGDH interacts with Hu antigen R (HuR) and converts UDP-glucose to UDP-glucuronic acid, which attenuates the UDP-glucose-mediated inhibition of the association of HuR with SNAI1 mRNA and therefore enhances the stability of SNAI1 mRNA. Increased production of SNAIL initiates the epithelial-mesenchymal transition, thus promoting the migration of tumour cells and lung cancer metastasis. In addition, phosphorylation of UGDH at tyrosine 473 correlates with metastatic recurrence and poor prognosis of patients with lung cancer. Our findings reveal a tumour-suppressive role of UDP-glucose in lung cancer metastasis and uncover a mechanism by which UGDH promotes tumour metastasis by increasing the stability of SNAI1 mRNA.


Assuntos
Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Neoplásica/genética , Metástase Neoplásica/prevenção & controle , Estabilidade de RNA , Fatores de Transcrição da Família Snail/genética , Uridina Difosfato Glucose/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proteína Semelhante a ELAV 1/deficiência , Proteína Semelhante a ELAV 1/genética , Proteína Semelhante a ELAV 1/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Nus , Fosfotirosina/metabolismo , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Fatores de Transcrição da Família Snail/biossíntese , Uridina Difosfato Glucose Desidrogenase/química , Uridina Difosfato Glucose Desidrogenase/genética , Uridina Difosfato Glucose Desidrogenase/metabolismo , Uridina Difosfato Ácido Glucurônico/metabolismo
15.
Nano Lett ; 24(20): 6023-6030, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739284

RESUMO

Construction of diatomic rotors, which is crucial for artificial nanomachines, remains challenging due to surface constraints and limited chemical design. Here we report the construction of diatomic Cr-Cs and Fe-Cs rotors where a Cr or Fe atom switches around a Cs atom at the Sb surface of the newly discovered kagome superconductor CsV3Sb5. The switching rate is controlled by the bias voltage between the rotor and scanning tunneling microscope (STM) tip. The spatial distribution of rates exhibits C2 symmetry, possibly linked to the symmetry-breaking charge orders of CsV3Sb5. We have expanded the rotor construction to include different transition metals (Cr, Fe, V) and alkali metals (Cs, K). Remarkably, designed configurations of rotors are achieved through STM manipulation. Rotor orbits and quantum states are precisely controlled by tuning the inter-rotor distance. Our findings establish a novel platform for the controlled fabrication of atomic motors on symmetry-breaking quantum materials, paving the way for advanced nanoscale devices.

16.
Nano Lett ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007508

RESUMO

A kagome lattice hosts a plethora of quantum states arising from the interplay between nontrivial topology and electron correlations. The recently discovered kagome magnet RMn6Sn6 (R represents a rare-earth element) is believed to showcase a kagome band closely resembling textbook characteristics. Here, we report the characterization of local electronic states and their magnetization response in YMn6Sn6 via scanning tunneling microscopy measurements under vector magnetic fields. Our spectroscopic maps reveal a spontaneously trimerized kagome electronic order in YMn6Sn6, where the 6-fold rotational symmetry is disrupted while translational symmetry is maintained. Further application of an external magnetic field demonstrates a strong coupling of the YMn6Sn6 kagome band to the field, which exhibits an energy shift discrepancy under different field directions, implying the existence of magnetization-response anisotropy and anomalous g factors. Our findings establish YMn6Sn6 as an ideal platform for investigating kagome-derived orbital magnetic moment and correlated magnetic topological states.

17.
Nano Lett ; 24(22): 6560-6567, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775289

RESUMO

Kagome lattice AV3Sb5 has attracted tremendous interest because it hosts correlated and topological physics. However, an in-depth understanding of the temperature-driven electronic states in AV3Sb5 is elusive. Here we use scanning tunneling microscopy to directly capture the rotational symmetry-breaking effect in KV3Sb5. Through both topography and spectroscopic imaging of defect-free KV3Sb5, we observe a charge density wave (CDW) phase transition from an a0 × a0 atomic lattice to a robust 2a0 × 2a0 superlattice upon cooling the sample to 60 K. An individual Sb-atom vacancy in KV3Sb5 further gives rise to the local Friedel oscillation (FO), visible as periodic charge modulations in spectroscopic maps. The rotational symmetry of the FO tends to break at the temperature lower than 40 K. Moreover, the FO intensity shows an obvious competition against the intensity of the CDW. Our results reveal a tantalizing electronic nematicity in KV3Sb5, highlighting the multiorbital correlation in the kagome lattice framework.

18.
J Mol Cell Cardiol ; 193: 1-10, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38789075

RESUMO

BACKGROUND: Hypothermic ischemia-reperfusion arrhythmia is a common complication of cardiothoracic surgery under cardiopulmonary bypass, but few studies have focused on this type of arrhythmia. Our prior study discovered reduced myocardial Cx43 protein levels may be linked to hypothermic reperfusion arrhythmias. However, more detailed molecular mechanism research is required. METHOD: The microRNA and mRNA expression levels in myocardial tissues were detected by real-time quantitative PCR (RT-qPCR). Besides, the occurrence of hypothermic reperfusion arrhythmias and changes in myocardial electrical conduction were assessed by electrocardiography and ventricular epicardial activation mapping. Furthermore, bioinformatics analysis, applying antagonists of miRNA, western blotting, immunohistochemistry, a dual luciferase assay, and pearson correlation analysis were performed to investigate the underlying molecular mechanisms. RESULTS: The expression level of novel-miR-17 was up-regulated in hypothermic ischemia-reperfusion myocardial tissues. Inhibition of novel-miR-17 upregulation ameliorated cardiomyocyte edema, reduced apoptosis, increased myocardial electrical conduction velocity, and shortened the duration of reperfusion arrhythmias. Mechanistic studies showed that novel-miR-17 reduced the expression of Cx43 by directly targeting Gja1 while mediating the activation of the PKC/c-Jun signaling pathway. CONCLUSION: Up-regulated novel-miR-17 is a newly discovered pro-arrhythmic microRNA that may serve as a potential therapeutic target and biomarker for hypothermic reperfusion arrhythmias.


Assuntos
Arritmias Cardíacas , Conexina 43 , MicroRNAs , Proteína Quinase C , Transdução de Sinais , Regulação para Cima , Conexina 43/metabolismo , Conexina 43/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/patologia , Proteína Quinase C/metabolismo , Proteína Quinase C/genética , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/etiologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Apoptose/genética , Ratos , Humanos , Miocárdio/metabolismo , Miocárdio/patologia
19.
Int J Cancer ; 155(4): 697-709, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577882

RESUMO

Patient-derived organoids (PDOs) may facilitate treatment selection. This retrospective cohort study evaluated the feasibility and clinical benefit of using PDOs to guide personalized treatment in metastatic breast cancer (MBC). Patients diagnosed with MBC were recruited between January 2019 and August 2022. PDOs were established and the efficacy of customized drug panels was determined by measuring cell mortality after drug exposure. Patients receiving organoid-guided treatment (OGT) were matched 1:2 by nearest neighbor propensity scores with patients receiving treatment of physician's choice (TPC). The primary outcome was progression-free survival. Secondary outcomes included objective response rate and disease control rate. Targeted gene sequencing and pathway enrichment analysis were performed. Forty-six PDOs (46 of 51, 90.2%) were generated from 45 MBC patients. PDO drug screening showed an accuracy of 78.4% (95% CI 64.9%-91.9%) in predicting clinical responses. Thirty-six OGT patients were matched to 69 TPC patients. OGT was associated with prolonged median progression-free survival (11.0 months vs. 5.0 months; hazard ratio 0.53 [95% CI 0.33-0.85]; p = .01) and improved disease control (88.9% vs. 63.8%; odd ratio 4.26 [1.44-18.62]) compared with TPC. The objective response rate of both groups was similar. Pathway enrichment analysis in hormone receptor-positive, human epidermal growth factor receptor 2-negative patients demonstrated differentially modulated pathways implicated in DNA repair and transcriptional regulation in those with reduced response to capecitabine/gemcitabine, and pathways associated with cell cycle regulation in those with reduced response to palbociclib. Our study shows that PDO-based functional precision medicine is a feasible and effective strategy for MBC treatment optimization and customization.


Assuntos
Neoplasias da Mama , Organoides , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Organoides/patologia , Organoides/efeitos dos fármacos , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Adulto , Medicina de Precisão/métodos , Intervalo Livre de Progressão , Metástase Neoplásica , Piridinas/uso terapêutico , Piridinas/administração & dosagem , Piperazinas/uso terapêutico , Piperazinas/administração & dosagem , Resultado do Tratamento
20.
Small ; : e2401957, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682730

RESUMO

Prussian blue analogues (PBAs) have emerged as highly promising cathode materials for sodium-ion batteries (SIBs) due to their affordability, facile synthesis, porous framework, and high theoretical capacity. Despite their considerable potential, practical applications of PBAs face significant challenges that limit their performance. This review offers a comprehensive retrospective analysis of PBAs' development history as cathode materials, delving into their reaction mechanisms, including charge compensation and ion diffusion mechanisms. Furthermore, to overcome these challenges, a range of improvement strategies are proposed, encompassing modifications in synthesis techniques and enhancements in structural stability. Finally, the commercial viability of PBAs is examined, alongside discussions on advanced synthesis methods and existing concerns regarding cost and safety, aiming to foster ongoing advancements of PBAs for practical SIBs.

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