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1.
Cell ; 173(5): 1135-1149.e15, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29754817

RESUMO

A primary cause of disease progression in type 2 diabetes (T2D) is ß cell dysfunction due to inflammatory stress and insulin resistance. However, preventing ß cell exhaustion under diabetic conditions is a major therapeutic challenge. Here, we identify the vitamin D receptor (VDR) as a key modulator of inflammation and ß cell survival. Alternative recognition of an acetylated lysine in VDR by bromodomain proteins BRD7 and BRD9 directs association to PBAF and BAF chromatin remodeling complexes, respectively. Mechanistically, ligand promotes VDR association with PBAF to effect genome-wide changes in chromatin accessibility and enhancer landscape, resulting in an anti-inflammatory response. Importantly, pharmacological inhibition of BRD9 promotes PBAF-VDR association to restore ß cell function and ameliorate hyperglycemia in murine T2D models. These studies reveal an unrecognized VDR-dependent transcriptional program underpinning ß cell survival and identifies the VDR:PBAF/BAF association as a potential therapeutic target for T2D.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Fatores de Transcrição/metabolismo , Vitamina D/farmacologia , Animais , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Montagem e Desmontagem da Cromatina , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Humanos , Insulina/sangue , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Mutagênese Sítio-Dirigida , Fosforilação Oxidativa/efeitos dos fármacos , Ligação Proteica , Interferência de RNA , RNA Guia de Cinetoplastídeos/genética , RNA Interferente Pequeno/metabolismo , Receptores de Calcitriol/antagonistas & inibidores , Receptores de Calcitriol/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos
2.
Cell ; 165(7): 1644-1657, 2016 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-27238018

RESUMO

Defects in circadian rhythm influence physiology and behavior with implications for the treatment of sleep disorders, metabolic disease, and cancer. Although core regulatory components of clock rhythmicity have been defined, insight into the mechanisms underpinning amplitude is limited. Here, we show that REV-ERBα, a core inhibitory component of clock transcription, is targeted for ubiquitination and subsequent degradation by the F-box protein FBXW7. By relieving REV-ERBα-dependent repression, FBXW7 provides an unrecognized mechanism for enhancing the amplitude of clock gene transcription. Cyclin-dependent kinase 1 (CDK1)-mediated phosphorylation of REV-ERBα is necessary for FBXW7 recognition. Moreover, targeted hepatic disruption of FBXW7 alters circadian expression of core clock genes and perturbs whole-body lipid and glucose levels. This CDK1-FBXW7 pathway controlling REV-ERBα repression defines an unexpected molecular mechanism for re-engaging the positive transcriptional arm of the clock, as well as a potential route to manipulate clock amplitude via small molecule CDK1 inhibition.


Assuntos
Ritmo Circadiano , Proteínas F-Box/metabolismo , Fígado/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Relógios Circadianos , Proteínas F-Box/genética , Proteína 7 com Repetições F-Box-WD , Técnicas de Inativação de Genes , Humanos , Metabolismo dos Lipídeos , Camundongos , Fosforilação , Processamento de Proteína Pós-Traducional , Transcriptoma , Ubiquitina-Proteína Ligases/genética
3.
Cell ; 152(3): 381-2, 2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23374332

RESUMO

Central circadian clock oscillators, located in the suprachiasmatic nucleus (SCN) of the hypothalamus, align peripheral clock systems with geosynchronous time. Gerber et al. (2013) identify actin polymerization and serum response factor (SRF) activation as key steps linking the central master clock to peripheral oscillators.

4.
Proc Natl Acad Sci U S A ; 121(38): e2322764121, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39250662

RESUMO

Are members of marginalized communities silenced on social media when they share personal experiences of racism? Here, we investigate the role of algorithms, humans, and platform guidelines in suppressing disclosures of racial discrimination. In a field study of actual posts from a neighborhood-based social media platform, we find that when users talk about their experiences as targets of racism, their posts are disproportionately flagged for removal as toxic by five widely used moderation algorithms from major online platforms, including the most recent large language models. We show that human users disproportionately flag these disclosures for removal as well. Next, in a follow-up experiment, we demonstrate that merely witnessing such suppression negatively influences how Black Americans view the community and their place in it. Finally, to address these challenges to equity and inclusion in online spaces, we introduce a mitigation strategy: a guideline-reframing intervention that is effective at reducing silencing behavior across the political spectrum.


Assuntos
Racismo , Mídias Sociais , Humanos , Negro ou Afro-Americano , Algoritmos
5.
Proc Natl Acad Sci U S A ; 121(42): e2411321121, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39383000

RESUMO

Profound functional switch of key regulatory factors may play a major role in homeostasis and disease. Dysregulation of circadian rhythm (CR) is strongly implicated in cancer with mechanisms poorly understood. We report here that the function of REV-ERBα, a major CR regulator of the orphan nuclear receptor subfamily, is dramatically altered in tumors in both its genome binding and functional mode. Loss of CR is linked to a functional inversion of REV-ERBα from a repressor in control of CR and metabolic gene programs in normal tissues to a strong activator in different cancers. Through changing its association from NCoR/HDAC3 corepressor complex to BRD4/p300 coactivators, REV-ERBα directly activates thousands of genes including tumorigenic programs such as MAPK and PI3K-Akt signaling. Functioning as a master transcriptional activator, REV-ERBα partners with pioneer factor FOXA1 and directly stimulates a large number of signaling genes, including multiple growth factors, receptor tyrosine kinases, RASs, AKTs, and MAPKs. Moreover, elevated REV-ERBα reprograms FOXA1 to bind new targets through a BRD4-mediated increase in local chromatin accessibility. Pharmacological targeting with SR8278 diminishes the function of both REV-ERBα and FOXA1 and synergizes with BRD4 inhibitor in effective suppression of tumorigenic programs and tumor growth. Thus, our study revealed a functional inversion by a CR regulator in driving gene reprogramming as an unexpected paradigm of tumorigenesis mechanism and demonstrated a high effectiveness of therapeutic targeting such switch.


Assuntos
Carcinogênese , Ritmo Circadiano , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Humanos , Animais , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Carcinogênese/genética , Camundongos , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Fator 3-alfa Nuclear de Hepatócito/genética , Transdução de Sinais , Linhagem Celular Tumoral , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 1 de Receptor Nuclear/genética , Proteínas que Contêm Bromodomínio
6.
Nat Methods ; 20(3): 387-399, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36797409

RESUMO

Spatial omics technologies generate wealthy but highly complex datasets. Here we present Spatial Omics DataBase (SODB), a web-based platform providing both rich data resources and a suite of interactive data analytical modules. SODB currently maintains >2,400 experiments from >25 spatial omics technologies, which are freely accessible as a unified data format compatible with various computational packages. SODB also provides multiple interactive data analytical modules, especially a unique module, Spatial Omics View (SOView). We conduct comprehensive statistical analyses and illustrate the utility of both basic and advanced analytical modules using multiple spatial omics datasets. We demonstrate SOView utility with brain spatial transcriptomics data and recover known anatomical structures. We further delineate functional tissue domains with associated marker genes that were obscured when analyzed using previous methods. We finally show how SODB may efficiently facilitate computational method development. The SODB website is https://gene.ai.tencent.com/SpatialOmics/ . The command-line package is available at https://pysodb.readthedocs.io/en/latest/ .


Assuntos
Perfilação da Expressão Gênica , Software , Bases de Dados Factuais , Perfilação da Expressão Gênica/métodos
7.
Circ Res ; 134(5): 550-568, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38323433

RESUMO

BACKGROUND: Doxorubicin is an effective chemotherapeutic agent, but its use is limited by acute and chronic cardiotoxicity. Exercise training has been shown to protect against doxorubicin-induced cardiotoxicity, but the involvement of immune cells remains unclear. This study aimed to investigate the role of exercise-derived B cells in protecting against doxorubicin-induced cardiotoxicity and to further determine whether B cell activation and antibody secretion play a role in this protection. METHODS: Mice that were administered with doxorubicin (5 mg/kg per week, 20 mg/kg cumulative dose) received treadmill running exercise. The adoptive transfer of exercise-derived splenic B cells to µMT-/- (B cell-deficient) mice was performed to elucidate the mechanism of B cell regulation that mediated the effect of exercise. RESULTS: Doxorubicin-administered mice that had undergone exercise training showed improved cardiac function, and low levels of cardiac apoptosis, atrophy, and fibrosis, and had reduced cardiac antibody deposition and proinflammatory responses. Similarly, B cell pharmacological and genetic depletion alleviated doxorubicin-induced cardiotoxicity, which phenocopied the protection of exercise. In vitro performed coculture experiments confirmed that exercise-derived B cells reduced cardiomyocyte apoptosis and fibroblast activation compared with control B cells. Importantly, the protective effect of exercise on B cells was confirmed by the adoptive transfer of splenic B cells from exercised donor mice to µMT-/- recipient mice. However, blockage of Fc gamma receptor IIB function using B cell transplants from exercised Fc gamma receptor IIB-/- mice abolished the protection of exercise-derived B cells against doxorubicin-induced cardiotoxicity. Mechanistically, we found that Fc gamma receptor IIB, an important B cell inhibitory receptor, responded to exercise and increased B cell activation threshold, which participated in exercise-induced protection against doxorubicin-induced cardiotoxicity. CONCLUSIONS: Our results demonstrate that exercise training protects against doxorubicin-induced cardiotoxicity by upregulating Fc gamma receptor IIB expression in B cells, which plays an important anti-inflammatory role and participates in the protective effect of exercise against doxorubicin-induced cardiotoxicity.


Assuntos
Cardiotoxicidade , Miócitos Cardíacos , Camundongos , Animais , Cardiotoxicidade/metabolismo , Miócitos Cardíacos/metabolismo , Doxorrubicina/toxicidade , Apoptose
8.
Cancer Metastasis Rev ; 43(3): 1075-1093, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38592427

RESUMO

The current CAR-T cell therapy products have been hampered in their druggability due to the personalized preparation required, unclear pharmacokinetic characteristics, and unpredictable adverse reactions. Enabling standardized manufacturing and having clear efficacy and pharmacokinetic characteristics are prerequisites for ensuring the effective practicality of CAR-T cell therapy drugs. This review provides a broad overview of the different approaches for controlling behaviors of CAR-T cells in vivo. The utilization of genetically modified vectors enables in vivo production of CAR-T cells, thereby abbreviating or skipping the lengthy in vitro expansion process. By equipping CAR-T cells with intricately designed control elements, using molecule switches or small-molecule inhibitors, the control of CAR-T cell activity can be achieved. Moreover, the on-off control of CAR-T cell activity would yield potential gains in phenotypic remodeling. These methods provide beneficial references for the future development of safe, controllable, convenient, and suitable for standardized production of CAR-T cell therapy products.


Assuntos
Imunoterapia Adotiva , Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva/métodos , Animais , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Linfócitos T/imunologia
9.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36567255

RESUMO

Underlying medical conditions, such as cancer, kidney disease and heart failure, are associated with a higher risk for severe COVID-19. Accurate classification of COVID-19 patients with underlying medical conditions is critical for personalized treatment decision and prognosis estimation. In this study, we propose an interpretable artificial intelligence model termed VDJMiner to mine the underlying medical conditions and predict the prognosis of COVID-19 patients according to their immune repertoires. In a cohort of more than 1400 COVID-19 patients, VDJMiner accurately identifies multiple underlying medical conditions, including cancers, chronic kidney disease, autoimmune disease, diabetes, congestive heart failure, coronary artery disease, asthma and chronic obstructive pulmonary disease, with an average area under the receiver operating characteristic curve (AUC) of 0.961. Meanwhile, in this same cohort, VDJMiner achieves an AUC of 0.922 in predicting severe COVID-19. Moreover, VDJMiner achieves an accuracy of 0.857 in predicting the response of COVID-19 patients to tocilizumab treatment on the leave-one-out test. Additionally, VDJMiner interpretively mines and scores V(D)J gene segments of the T-cell receptors that are associated with the disease. The identified associations between single-cell V(D)J gene segments and COVID-19 are highly consistent with previous studies. The source code of VDJMiner is publicly accessible at https://github.com/TencentAILabHealthcare/VDJMiner. The web server of VDJMiner is available at https://gene.ai.tencent.com/VDJMiner/.


Assuntos
Asma , COVID-19 , Humanos , Inteligência Artificial , Curva ROC , Software
10.
FASEB J ; 38(20): e70126, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39446097

RESUMO

Obesity, recognized as a risk factor for nonunion, detrimentally impacts bone health, with significant physical and economic repercussions for affected individuals. Nevertheless, the precise pathomechanisms by which obesity impairs fracture healing remain insufficiently understood. Multiple studies have identified neutrophil granulocytes as key players in the systemic immune response, being the predominant immune cells in early fracture hematomas. This study identified a previously unreported critical period for neutrophil infiltration into the callus. In vivo experiments demonstrated that diet-induced obesity (DIO) mice showed earlier neutrophil infiltration, along with increased formation of neutrophil extracellular traps (NETs), compared to control mice during the endochondral phase of fracture repair. Furthermore, Padi4 knockout was found to reduce NET formation and mitigate the fracture healing delays caused by high-fat diets. Mechanistically, in vitro analyses revealed that NETs, by activating NLRP3 inflammasomes, inhibited the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and concurrently promoted M1-like macrophage polarization. These findings establish a connection between NET formation during the endochondral phase and delayed fracture healing, suggesting that targeting NETs could serve as a promising therapeutic approach for addressing obesity-induced delays in fracture recovery.


Assuntos
Dieta Hiperlipídica , Armadilhas Extracelulares , Consolidação da Fratura , Camundongos Endogâmicos C57BL , Obesidade , Proteína-Arginina Desiminase do Tipo 4 , Animais , Armadilhas Extracelulares/metabolismo , Camundongos , Consolidação da Fratura/fisiologia , Obesidade/metabolismo , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Dieta Hiperlipídica/efeitos adversos , Neutrófilos/metabolismo , Neutrófilos/imunologia , Camundongos Knockout , Masculino , Células-Tronco Mesenquimais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Osteogênese/fisiologia , Macrófagos/metabolismo , Macrófagos/imunologia
11.
Nucleic Acids Res ; 51(17): 8970-8986, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37522386

RESUMO

Dot1l is a histone methyltransferase without a SET domain and is responsible for H3K79 methylation, which marks active transcription. In contradiction, Dot1l also participates in silencing gene expression. The target regions and mechanism of Dot1l in repressing transcription remain enigmatic. Here, we show that Dot1l represses endogenous retroviruses in embryonic stem cells (ESCs). Specifically, the absence of Dot1l led to the activation of MERVL, which is a marker of 2-cell-like cells. In addition, Dot1l deletion activated the 2-cell-like state and predisposed ESCs to differentiate into trophectoderm lineage. Transcriptome analysis revealed activation of 2-cell genes and meiotic genes by Dot1l deletion. Mechanistically, Dot1l interacted with and co-localized with Npm1 on MERVL, and depletion of Npm1 similarly augmented MERVL expression. The catalytic activity and AT-hook domain of Dot1l are important to suppress MERVL. Notably, Dot1l-Npm1 restricts MERVL by regulating protein level and deposition of histone H1. Furthermore, Dot1l is critical for Npm1 to efficiently interact with histone H1 and inhibit ubiquitination of H1 whereas Npm1 is essential for Dot1l to interact with MERVL. Altogether, we discover that Dot1l represses MERVL through chaperoning H1 by collaborating with Npm1. Importantly, our findings shed light on the non-canonical transcriptional repressive role of Dot1l in ESCs.


Assuntos
Retrovirus Endógenos , Animais , Camundongos , Células-Tronco Embrionárias/metabolismo , Retrovirus Endógenos/genética , Retrovirus Endógenos/metabolismo , Histona Metiltransferases/genética , Histonas/genética , Histonas/metabolismo , Metilação , Metiltransferases/genética
12.
Nano Lett ; 24(23): 7077-7083, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38828922

RESUMO

The study of exciton polarons has offered profound insights into the many-body interactions between bosonic excitations and their immersed Fermi sea within layered heterostructures. However, little is known about the properties of exciton polarons with interlayer interactions. Here, through magneto-optical reflectance contrast measurements, we experimentally investigate interlayer Fermi polarons for 2s excitons in WSe2/graphene heterostructures, where the excited exciton states (2s) in the WSe2 layer are dressed by free charge carriers of the adjacent graphene layer in the Landau quantization regime. First, such a system enables an optical detection of integer and fractional quantum Hall states (e.g., ν = ±1/3, ±2/3) of monolayer graphene. Furthermore, we observe that the 2s state evolves into two distinct branches, denoted as attractive and repulsive polarons, when graphene is doped out of the incompressible quantum Hall gaps. Our work paves the way for the understanding of the excited composite quasiparticles and Bose-Fermi mixtures.

13.
Infect Immun ; 92(10): e0017224, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39207146

RESUMO

Abdominal aortic aneurysm (AAA) is a life-threatening cardiovascular disease that has been linked to gut microbiome dysbiosis. Therefore, this study aims to investigate the effects of Akkermansia muciniphila (Am) on AAA mice and the biomolecules involved. AAA mice were generated using angiotensin II (Ang II), and 16sRNA sequencing was used to identify an altered abundance of microbiota in the feces of AAA mice. Vascular smooth muscle cell (VSMC) markers and apoptosis, and macrophage infiltration in mouse aortic tissues were examined. The abundance of Am was reduced in AAA mouse feces, and endothelial PAS domain-containing protein 1 (EPAS1) was downregulated in AAA mice and VSMC induced with Ang II. Am delayed AAA progression in mice, which was blunted by knockdown of EPAS1. EPAS1 was bound to the Cbp/p300-interacting transactivator 2 (CITED2) promoter and promoted CITED2 transcription. CITED2 reduced VSMC apoptosis and delayed AAA progression. Moreover, EPAS1 inhibited macrophage inflammatory response by promoting CITED2 transcription. In conclusion, gut microbiome dysbiosis in AAA induces EPAS1-mediated dysregulation of CITED2 to promote macrophage inflammatory response and VSMC apoptosis.


Assuntos
Akkermansia , Aneurisma da Aorta Abdominal , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Microbioma Gastrointestinal , Transativadores , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Aneurisma da Aorta Abdominal/microbiologia , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Camundongos , Transativadores/metabolismo , Transativadores/genética , Masculino , Modelos Animais de Doenças , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/microbiologia , Músculo Liso Vascular/patologia , Apoptose , Angiotensina II/metabolismo , Miócitos de Músculo Liso/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Disbiose/microbiologia
14.
J Am Chem Soc ; 146(40): 27382-27391, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39320981

RESUMO

Proteolysis-targeting chimeras (PROTACs) show promise in tumor treatment. However, the E3 ligases VHL and CRBN, commonly used in PROTAC, are highly expressed in only a few tumors, thus limiting the application scope and efficacy of PROTAC drugs. Furthermore, the lack of tumor specificity in PROTAC drugs can result in toxic side effects. Therefore, there is an urgent need to develop tumor-selective PROTAC drugs that do not rely on endogenous E3 ligases. In this study, we introduce the ClickRNA-PROTAC system, which involves the expression of a fusion protein of the E3 ubiquitin ligase SIAH1 and SNAPTag through mRNA transfection and recruits the protein of interest (POI) using bio-orthogonal click chemistry. ClickRNA-PROTAC can effectively degrade various proteins such as BRD4, KRAS, and NFκB simply by replacing the warhead molecules. By employing a tumor-specific mRNA-responsive translation strategy, ClickRNA-PROTAC can selectively degrade POIs in tumor cells. Furthermore, ClickRNA-PROTAC demonstrated strong efficacy in targeted cancer therapy in a xenograft mouse model of adrenocortical carcinoma. In conclusion, this approach offers several advantages, including independence from endogenous E3 ubiquitin ligases, tumor specificity, and programmability, thereby paving the way for the development of PROTAC drugs.


Assuntos
Proteólise , Humanos , Proteólise/efeitos dos fármacos , Animais , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Química Click , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
15.
J Am Chem Soc ; 146(14): 9493-9498, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38530089

RESUMO

The thermodynamic favorability of an alkaline solution for the oxidation of water suggests the need for developing hydrogen evolution reaction (HER) catalysts that can function in basic aqueous solutions so that both of the half reactions in overall water splitting can occur in mutually compatible solutions. Although photocatalytic HERs have been reported mostly in acidic solutions and a few at basic pHs in mixed organic aqueous solutions, visible-light driven HER catalyzed by molecular metal complexes in purely alkaline aqueous solutions remains largely unexplored. Here, we report a new cobalt complex with a tetrapyridylamine ligand that catalyzes photolytic HER with turnover number up to 218 000 in purely aqueous solutions at pH 9.0. Density functional theory (DFT) calculations suggested a modified electron transfer (E)-proton transfer (C)-electron transfer (E)-proton transfer (C) (mod-ECEC) pathway for hydrogen production from the protonation of CoII-H species. The remarkable catalytic activity resulting from subtle structural changes of the ligand scaffold highlights the importance of studying structure-function relationships in molecular catalyst design. Our present work significantly advances the development of a molecular metal catalyst for visible-light driven HER in more challenging alkaline aqueous solutions that holds substantial promise in solar-driven water-splitting systems.

16.
Cancer Immunol Immunother ; 73(1): 13, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231412

RESUMO

BACKGROUND: Although chimeric antigen receptor T (CAR-T) cells have been proven to be an effective way of treating B cell malignancies, a lot of patients could not benefit from it because of failure in CAR-T cell manufacturing, disease progression, and unaffordable price. The study aimed to explore universal CAR-T cell products to extend the clinical accessibility. METHODS: The antitumor activity of CRISPR/Cas9-edited allogeneic anti-CD19 CAR-T (CAR-T19) cells was assessed in vitro, in animal models, and in patients with relapsed/refractory (R/R) acute B cell lymphoblastic leukemia (B-ALL) or diffuse large B cell lymphoma. RESULTS: B2M-/TRAC- universal CAR-T19 (U-CAR-T19) cells exhibited powerful anti-leukemia abilities both in vitro and in animal models, as did primary CD19+ leukemia cells from leukemia patients. However, expansion, antitumor efficacy, or graft-versus-host-disease (GvHD) was not observed in six patients with R/R B cell malignancies after U-CAR-T19 cell infusion. Accordingly, significant activation of natural killer (NK) cells by U-CAR-T19 cells was proven both clinically and in vitro. HLA-A-/B-/TRAC- novel CAR-T19 (nU-CAR-T19) cells were constructed with similar tumoricidal capacity but resistance to NK cells in vitro. Surprisingly, robust expansion of nU-CAR-T19 cells, along with rapid eradication of CD19+ abnormal B cells, was observed in the peripheral blood and bone marrow of another three patients with R/R B-ALL. The patients achieved complete remission with no detectable minimal residual disease 14 days after the infusion of nU-CAR-T19 cells. Two of the three patients had grade 2 cytokine release syndrome, which were managed using an IL-6 receptor blocker. Most importantly, GvHD was not observed in any patient, suggesting the safety of TRAC-disrupted CAR-T cells generated using the CRISPR/Cas9 method for clinical application. CONCLUSIONS: The nU-CAR-T19 cells showed a strong response in R/R B-ALL. nU-CAR-T19 cells have the potential to be a promising new approach for treating R/R B cell malignancies.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Linfocítica Crônica de Células B , Leucemia , Receptores de Antígenos Quiméricos , Animais , Humanos , Receptores de Antígenos Quiméricos/genética , Anticorpos , Antígenos CD19 , Linfócitos T , Antígenos HLA-A
17.
Mol Carcinog ; 63(7): 1362-1377, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38656551

RESUMO

Acetyl-CoAacyltransferase2 (ACAA2) is a key enzyme in the fatty acid oxidation pathway that catalyzes the final step of mitochondrial ß oxidation, which plays an important role in fatty acid metabolism. The expression of ACAA2 is closely related to the occurrence and malignant progression of tumors. However, the function of ACAA2 in ovarian cancer is unclear. The expression level and prognostic value of ACAA2 were analyzed by databases. Gain and loss of function were carried out to explore the function of ACAA2 in ovarian cancer. RNA-seq and bioinformatics methods were applied to illustrate the regulatory mechanism of ACAA2. ACAA2 overexpression promoted the growth, proliferation, migration, and invasion of ovarian cancer, and ACAA2 knockdown inhibited the malignant progression of ovarian cancer as well as the ability of subcutaneous tumor formation in nude mice. At the same time, we found that OGT can induce glycosylation modification of ACAA2 and regulate the karyoplasmic distribution of ACAA2. OGT plays a vital role in ovarian cancer as a function of oncogenes. In addition, through RNA-seq sequencing, we found that ACAA2 regulates the expression of DIXDC1. ACAA2 regulated the malignant progression of ovarian cancer through the WNT/ß-Catenin signaling pathway probably. ACAA2 is an oncogene in ovarian cancer and has the potential to be a target for ovarian cancer therapy.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Via de Sinalização Wnt , Prognóstico , Carcinogênese/genética
18.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36571479

RESUMO

MOTIVATION: Precise reconstruction of neuronal arbors is important for circuitry mapping. Many auto-tracing algorithms have been developed toward full reconstruction. However, it is still challenging to trace the weak signals of neurite fibers that often correspond to axons. RESULTS: We proposed a method, named the NeuMiner, for tracing weak fibers by combining two strategies: an online sample mining strategy and a modified gamma transformation. NeuMiner improved the recall of weak signals (voxel values <20) by a large margin, from 5.1 to 27.8%. This is prominent for axons, which increased by 6.4 times, compared to 2.0 times for dendrites. Both strategies were shown to be beneficial for weak fiber recognition, and they reduced the average axonal spatial distances to gold standards by 46 and 13%, respectively. The improvement was observed on two prevalent automatic tracing algorithms and can be applied to any other tracers and image types. AVAILABILITY AND IMPLEMENTATION: Source codes of NeuMiner are freely available on GitHub (https://github.com/crazylyf/neuronet/tree/semantic_fnm). Image visualization, preprocessing and tracing are conducted on the Vaa3D platform, which is accessible at the Vaa3D GitHub repository (https://github.com/Vaa3D). All training and testing images are cropped from high-resolution fMOST mouse brains downloaded from the Brain Image Library (https://www.brainimagelibrary.org/), and the corresponding gold standards are available at https://doi.brainimagelibrary.org/doi/10.35077/g.25. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Software , Animais , Camundongos , Neurônios , Neuritos , Encéfalo
19.
Cancer Cell Int ; 24(1): 55, 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311725

RESUMO

BACKGROUND: Emerging data point to the critical role of snoRNA in the emergence of different types of cancer, but scarcely in breast cancer (BC). This study aimed to clarify the differential expressions and potential diagnostic value of SNORD16, SNORA73B, SCARNA4, and SNORD49B in BC. METHODS: We screened differential snoRNAs in BC tissues and adjacent tissues through SNORic datasets, and then we further verified them in the plasma of BC patients and healthy volunteers by quantitative polymerase chain reaction (qPCR). RESULTS: These four snoRNAs: SNORD16, SNORA73B, SCARNA4, and SNORD49B were considerably more abundant in cancerous tissues than in neighboring tissues in the TCGA database. Their plasma levels were also higher in BC and early-stage BC patients when compared to healthy controls. Furthermore, the ROC curve demonstrated that BC (AUC = 0.7521) and early-stage BC (AUC = 0.7305) might be successfully distinguished from healthy people by SNORD16, SNORA73B, SCARNA4, and SNORD49B. CONCLUSION: Plasma snoRNAs: SNORD16, SNORA73B, SCARNA4, and SNORD49B were upregulated in BC and early-stage BC and can be used as potential diagnostic markers for BC and early-stage BC.

20.
Cancer Cell Int ; 24(1): 3, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167096

RESUMO

PURPOSE: The alterations of RNA profile in tumor-educated platelets (TEPs) have been described as a novel biosource for cancer diagnostics. This study aimed to explore the potential snoRNAs in TEP as biomarkers for diagnostics of hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC). METHODS: Platelets were isolated using low-speed centrifugation and subjected to a quantitative polymerase chain reaction (qPCR) for snoRNAs detection. RESULTS: Down-regulated SNORD12B and SNORD14E as well as up-regulated SNORA63 were identified in TEP from HBV-related HCC, which could act as diagnostic biomarkers for HBV-related HCC as well as the early disease. Besides, TEP SNORD12B, SNORD14E, and SNORA63 facilitate the diagnostic performance of AFP and achieve favorable diagnostics efficiency for HBV-related HCC when combined with platelet parameters. CONCLUSIONS: Aberrant expression of SNORD12B, SNORA63, and SNORD14E in TEPs could serve as the novel and non-invasive biomarkers for HBV-related HCC diagnosis.

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