Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Ann Clin Lab Sci ; 51(4): 470-486, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34452885

RESUMO

OBJECTIVE: Epithelium-specific ETS protein 3 (Ese-3) is a member of the ETS family that is associated with tumor progression. However, there is little knowledge about Ese-3 in skin cancer. This study was conducted to explore the effects of Ese-3 on clinical prognosis in skin cancer and the functions of HaCaT cells. MATERIALS AND METHODS: Gene expression and clinical data were collected from The Cancer Genome Atlas (TCGA), The Genotype-Tissue Expression (GTEx), and three GSE datasets (GSE15605, GSE46517, and GSE114445). Comparison of data between groups was performed by Student's t-test and chi square test. Survival analysis was performed using log-rank test. Univariate and multivariate analyses were performed using Cox proportional hazards models. Enrichment analysis was used to predict Ese-3 related functions. Cell proliferation assays, colony formation assays, and flow cytometry were used to assess cell proliferation, while Transwell assays analyzed cell migration and invasion. RESULTS: Compared with normal tissues, the Ese-3 mRNA in cutaneous malignant melanoma (CMM) patients was downregulated (P<0.0001). Ese-3 mRNA was associated with the T stage (χ 2=10.015, P=0.018), clinical stage (χ 2=4.122, P=0.042), and prognosis in CMM patients (P=0.0219) and was an independent prognostic predictor in CMM (HR=1.878, P=0.048). Enrichment analysis showed that differentially expressed proteins were associated with "protein kinase B (AKT) binding." CONCLUSION: Ese-3 inhibited the proliferation, migration, and invasion of HaCaT cells by downregulating PSIP1 and NUCKS1 expression levels to inactivate the phosphorylation of AKT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/antagonistas & inibidores , Fosfoproteínas/antagonistas & inibidores , Neoplasias Cutâneas/patologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Idoso , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Feminino , Células HaCaT , Humanos , Masculino , Invasividade Neoplásica , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Prognóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Taxa de Sobrevida , Fatores de Transcrição/genética
2.
Acta Pharmacol Sin ; 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349236

RESUMO

An epidemic of pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading worldwide. SARS-CoV-2 relies on its spike protein to invade host cells by interacting with the human receptor protein Angiotensin-Converting Enzymes 2 (ACE2). Therefore, designing an antibody or small-molecular entry blockers is of great significance for virus prevention and treatment. This study identified five potential small molecular anti-virus blockers via targeting SARS-CoV-2 spike protein by combining in silico technologies with in vitro experimental methods. The five molecules were natural products that binding to the RBD domain of SARS-CoV-2 was qualitatively and quantitively validated by both native Mass Spectrometry (MS) and Surface Plasmon Resonance (SPR). Anti-viral activity assays showed that the optimal molecule, H69C2, had a strong binding affinity (dissociation constant KD) of 0.0947 µM and anti-virus IC50 of 85.75 µM.

3.
Sci Adv ; 7(24)2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34117053

RESUMO

Currently, high-throughput approaches are lacking in the isolation of antibodies with functional readouts beyond simple binding. This situation has impeded the next generation of cancer immunotherapeutics, such as bispecific T cell engager (BiTE) antibodies or agonist antibodies against costimulatory receptors, from reaching their full potential. Here, we developed a highly efficient droplet-based microfluidic platform combining a lentivirus transduction system that enables functional screening of millions of antibodies to identify potential hits with desired functionalities. To showcase the capacity of this system, functional antibodies for CD40 agonism with low frequency (<0.02%) were identified with two rounds of screening. Furthermore, the versatility of the system was demonstrated by combining an anti-Her2 × anti-CD3 BiTE antibody library with functional screening, which enabled efficient identification of active anti-Her2 × anti-CD3 BiTE antibodies. The platform could revolutionize next-generation cancer immunotherapy drug development and advance medical research.

4.
Chem Commun (Camb) ; 57(37): 4588-4591, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33956028

RESUMO

We report a general palladium-catalyzed one-pot procedure for the synthesis of phosphonates, phosphinates and phosphine oxides from phenols mediated by sulfuryl fluoride. It features mild conditions, broad substrate scope, high functionality tolerance and water insensitivity. The utility of this procedure has been well demonstrated by gram-scale synthesis, sequential synthesis of click chemistry building blocks, late-stage decoration of drugs and natural products and on-DNA synthesis of phosphine oxide for a DNA-encoded library (DEL).

5.
Chemistry ; 27(31): 8214-8220, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33811386

RESUMO

DNA-encoded combinatorial chemical library (DEL) technology, an approach that combines the power of genetics and chemistry, has emerged as an invaluable tool in drug discovery. Skeletal diversity plays a fundamental importance in DEL applications, and relies heavily on novel DNA-compatible chemical reactions. We report herein a phylogenic chemical transformation strategy using DNA-conjugated benzoyl hydrazine as a common versatile precursor in azole chemical expansion of DELs. DNA-compatible reactions deriving from the common benzoyl hydrazine precursor showed excellent functional group tolerance with exceptional efficiency in the synthesis of various azoles, including oxadiazoles, thiadiazoles, and triazoles, under mild reaction conditions. The phylogenic chemical transformation strategy provides DELs a facile way to expand into various unique chemical spaces with privileged scaffolds and pharmacophores.


Assuntos
Azóis , Bibliotecas de Moléculas Pequenas , Técnicas de Química Combinatória , DNA , Descoberta de Drogas , Biblioteca Gênica
6.
Sens Actuators B Chem ; 337: 129786, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33753963

RESUMO

The rapid and sensitive diagnosis of the highly contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the crucial issues at the outbreak of the ongoing global pandemic that has no valid cure. Here, we propose a SARS-CoV-2 antibody conjugated magnetic graphene quantum dots (GQDs)-based magnetic relaxation switch (MRSw) that specifically recognizes the SARS-CoV-2. The probe of MRSw can be directly mixed with the test sample in a fully sealed vial without sample pretreatment, which largely reduces the testers' risk of infection during the operation. The closed-tube one-step strategy to detect SARS-CoV-2 is developed with home-made ultra-low field nuclear magnetic resonance (ULF NMR) relaxometry working at 118 µT. The magnetic GQDs-based probe shows ultra-high sensitivity in the detection of SARS-CoV-2 due to its high magnetic relaxivity, and the limit of detection is optimized to 248 Particles mL‒1. Meanwhile, the detection time in ULF NMR system is only 2 min, which can significantly improve the efficiency of detection. In short, the magnetic GQDs-based MRSw coupled with ULF NMR can realize a rapid, safe, and sensitive detection of SARS-CoV-2.

7.
Adv Sci (Weinh) ; 8(6): 2003091, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33747727

RESUMO

Using T-cell chimeric antigen receptors (CAR-T) to activate and redirect T cells to tumors expressing the cognate antigen represents a powerful approach in cancer therapy. However, normal tissues with low expression of tumor-associated antigens (TAAs) can be mistargeted, resulting in severe side effects. An approach using a collection of T cells expressing a diverse, 106-member combinatorial cellular library of CARs, in which members can be specifically enriched based on avidity for cell membrane antigens, is reported. Using CD38 as the target antigen, an efficient and effective selection of CARs specifically recognizing CD38+ tumor cells is demonstrated. These selected CAR-T's produce cytokines known to be associated with T cell activation in a CD38 expression-dependent manner. This avidity-based selection endows the engineered T cells with minimal off-tumor effects, while retaining robust antitumor efficacy both in vitro and in vivo. The described method may facilitate the application of CAR-T therapy to TAAs previously considered undruggable.

8.
Biotechnol J ; 16(6): e2100040, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33595922

RESUMO

Detection of pathogens with single-nucleotide variations is indispensable for the disease tracing, but remains technically challenging. The D614G mutation in the SARS-CoV-2 spike protein is known to markedly enhance viral infectivity but is difficult to detect. Here, we report an effective approach called "synthetic mismatch integrated crRNA guided Cas12a detection" (symRNA-Cas12a) to detect the D614 and G614 variants effectively. Using this method, we systemically screened a pool of crRNAs that contain all the possible nucleotide substitutions covering the -2 to +2 positions around the mutation and identify one crRNA that can efficiently increase the detection specificity by 13-fold over the ancestral crRNA. With this selected crRNA, the symRNA-Cas12a assay can detect as low as 10 copies of synthetic mutant RNA and the results are confirmed to be accurate by Sanger sequencing. Overall, we have developed the symRNA-Cas12a method to specifically, sensitively and rapidly detect the SARS-CoV-2 D614G mutation.


Assuntos
COVID-19 , RNA Guia , Sistemas CRISPR-Cas , Humanos , Mutação , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
9.
ACS Chem Biol ; 16(3): 491-500, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33586431

RESUMO

The outbreak of novel coronavirus SARS-CoV-2 has caused a worldwide threat to public health. COVID-19 patients with SARS-CoV-2 infection can develop clinical symptoms that are often confused with the infections of other respiratory pathogens. Sensitive and specific detection of SARS-CoV-2 with the ability to discriminate from other viruses is urgently needed for COVID-19 diagnosis. Herein, we streamlined a highly efficient CRISPR-Cas12a-based nucleic acid detection platform, termed Cas12a-linked beam unlocking reaction (CALIBURN). We show that CALIBURN could detect SARS-CoV-2 and other coronaviruses and influenza viruses with little cross-reactivity. Importantly, CALIBURN allowed accurate diagnosis of clinical samples with extremely low viral loads, which is a major obstacle for the clinical applications of existing CRISPR diagnostic platforms. When tested on the specimens from SARS-CoV-2-positive and negative donors, CALIBURN exhibited 73.0% positive and 19.0% presumptive positive rates and 100% specificity. Moreover, unlike existing CRISPR detection methods that were mainly restricted to respiratory specimens, CALIBURN displayed consistent performance across both respiratory and nonrespiratory specimens, suggesting its broad specimen compatibility. Finally, using a mouse model of SARS-CoV-2 infection, we demonstrated that CALIBURN allowed detection of coexisting pathogens without cross-reactivity from a single tissue specimen. Our results suggest that CALIBURN can serve as a versatile platform for the diagnosis of COVID-19 and other respiratory infectious diseases.


Assuntos
Proteínas de Bactérias/genética , Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas , Endodesoxirribonucleases/genética , RNA Viral/análise , SARS-CoV-2/química , Adenoviridae/química , Animais , COVID-19/genética , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Camundongos Endogâmicos BALB C , Técnicas de Amplificação de Ácido Nucleico , Sondas RNA/genética , RNA Viral/genética , Manejo de Espécimes , Espectrometria de Fluorescência
10.
Sci Bull (Beijing) ; 66(12): 1194-1204, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33495715

RESUMO

A key to tackling the coronavirus disease 2019 (COVID-19) pandemic is to understand how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) manages to outsmart host antiviral defense mechanisms. Stress granules (SGs), which are assembled during viral infection and function to sequester host and viral mRNAs and proteins, are part of the antiviral responses. Here, we show that the SARS-CoV-2 nucleocapsid (N) protein, an RNA binding protein essential for viral production, interacted with Ras-GTPase-activating protein SH3-domain-binding protein (G3BP) and disrupted SG assembly, both of which require intrinsically disordered region1 (IDR1) in N protein. The N protein partitioned into SGs through liquid-liquid phase separation with G3BP, and blocked the interaction of G3BP1 with other SG-related proteins. Moreover, the N protein domains important for phase separation with G3BP and SG disassembly were required for SARS-CoV-2 viral production. We propose that N protein-mediated SG disassembly is crucial for SARS-CoV-2 production.

11.
Adv Sci (Weinh) ; : 2001300, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-33042732

RESUMO

Cas12a-based systems, which detect specific nucleic acids via collateral cleavage of reporter DNA, display huge potentials for rapid diagnosis of infectious diseases. Here, the Manganese-enhanced Cas12a (MeCas12a) system is described, where manganese is used to increase the detection sensitivity up to 13-fold, enabling the detection of target RNAs as low as five copies. MeCas12a is also highly specific, and is able to distinguish between single nucleotide polymorphisms (SNPs) differing by a single nucleotide. MeCas12a can detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in clinical samples and distinguish between SARS-CoV-2 and Middle East respiratory syndrome coronavirus (MERS-CoV) RNA in simulated samples, thus offering an attractive alternative to other methods for the diagnosis of infectious diseases including COVID-19 and MERS.

12.
Adv Sci (Weinh) ; 7(16): 2000818, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32832353

RESUMO

Growth factor deficiency in adulthood constitutes a distinct clinical syndrome with significant morbidities including abnormal body composition, reduced energy, affective disturbances, dyslipidemia, and increased cardiovascular risk. Protein replacement therapies using recombinant proteins or enzymes represent the only approved treatment. Combinatorial antibodies have shown great promise as a new class of therapeutic molecules because they act as "mechanism-based antibodies" with both agonist and antagonist activities. Using leptin, a key hormone in energy metabolism, as an example, a function-guided approach is developed to select combinatorial antibodies with high potency and full agonist activity that substitute natural growth factors in vivo. The identified antibody shows identical biochemical properties and cellular profiles as leptin, and rescues leptin-deficiency in ob/ob mice. Remarkably, the antibody activates leptin receptors that are otherwise nonfunctional because of mutations (L372A and A409E). Combinatorial antibodies have significant advantages over recombinant proteins for chronical usage in terms of immunological tolerance and biological stability.

13.
iScience ; 23(6): 101197, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32544667

RESUMO

Although insulin is a life-saving medicine, administration by daily injection remains problematic. Our goal was to exploit the power of DNA-encoded libraries to identify molecules with insulin-like activity but with the potential to be developed as oral drugs. Our strategy involved using a 104-member DNA-encoded library containing 160 Traditional Chinese Medicines (nDEL) to identify molecules that bind to and activate the insulin receptor. Importantly, we used the natural ligand, insulin, to liberate bound molecules. Using this selection method on our relatively small, but highly diverse, nDEL yielded a molecule capable of both binding to and activating the insulin receptor. Chemical analysis showed this molecule to be a polycyclic analog of the guanidine metformin, a known drug used to treat diabetes. By using our protocol with other, even larger, DELs we can expect to identify additional organic molecules capable of binding to and activating the insulin receptor.

14.
Biochem Biophys Res Commun ; 533(2): 241-248, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-32381359

RESUMO

Natural products have been an invaluable source of drug discovery, but their targets remain largely unknown. Natural products enriched DNA-encoded chemical libraries (nDELs) empower the researchers to rapidly and economically screen numerous natural products against various protein targets, and therefore promote the elucidation of the molecular mechanisms. In this work, we used poly (ADP-ribose) polymerase 1 (PARP1), as an example to explore the usage of nDEL for the functional natural products selection. We used late-stage modification approach to label three positive binders with unique DNA barcodes, whose dissociation constants range from sub-micromolar to micromolar. The selection criterion was set up according to the enrichment of these controls. Five natural products selected by this criterion directly bind to PARP1 in SPR, among which luteolin exhibits the highest inhibitory activity against PARP1. Moreover, luteolin selectively induces accumulation of DNA double-strand breaks and G2/M phase arrest in BRCA-deficient cells. All the findings from these investigations on luteolin support that PARP1 inhibition is one of the mechanisms for its anti-cancer activity.


Assuntos
DNA/química , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/química , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , DNA/síntese química , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Humanos , Luteolina/síntese química , Luteolina/química , Luteolina/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/síntese química , Ligação Proteica , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Ressonância de Plasmônio de Superfície
16.
Chem Commun (Camb) ; 56(30): 4252, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32255116

RESUMO

Correction for 'Iridium-catalyzed C-H amidation of s-tetrazines' by Huan Xiong et al., Chem. Commun., 2020, DOI: 10.1039/d0cc01647k.

17.
Angew Chem Int Ed Engl ; 59(32): 13273-13280, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32282979

RESUMO

Conventional direct C-H selenylation suffers from simple selenation with limited atom economy and complicated reaction system. In this work, we designed benzoselenazolone as a novel bifunctional selenide reagent for both off- and on-DNA C-H selenylation under rhodium(III) catalysis. We show that using benzoselenazolone allowed production of a series of selenylation products containing an adjacent aminoacyl group in a fast and efficient way, with high atom economy. The synthetic application of this method was demonstrated by taking advantage of the amide functionality as a nucleophile, directing group, and amide coupling partner. This work shows great potential in facilitating rapid construction of selenium-containing DNA-encoded chemical libraries (SeDELs), and lays the foundation for the development of selenium-containing drugs.

18.
Chem Commun (Camb) ; 56(34): 4692-4695, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32211711

RESUMO

An efficient, selective and scalable C-H amidation of s-tetrazines under iridium(III) catalysis is reported. This reaction features a broad substrate scope, high functional group tolerance, and air and water tolerance. This reaction also shows great potential for the rapid preparation of tri- and tetra-functional building blocks, which can be applied either in bioconjugation or synthesis of DNA-encoded library.

19.
Genome Biol ; 21(1): 51, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102684

RESUMO

BACKGROUND: CRISPR-Cas9 has been developed as a therapeutic agent for various infectious and genetic diseases. In many clinically relevant applications, constitutively active CRISPR-Cas9 is delivered into human cells without a temporal control system. Excessive and prolonged expression of CRISPR-Cas9 can lead to elevated off-target cleavage. The need for modulating CRISPR-Cas9 activity over time and dose has created the demand of developing CRISPR-Cas off switches. Protein and small molecule-based CRISPR-Cas inhibitors have been reported in previous studies. RESULTS: We report the discovery of Cas9-inhibiting peptides from inoviridae bacteriophages. These peptides, derived from the periplasmic domain of phage major coat protein G8P (G8PPD), can inhibit the in vitro activity of Streptococcus pyogenes Cas9 (SpCas9) proteins in an allosteric manner. Importantly, the inhibitory activity of G8PPD on SpCas9 is dependent on the order of guide RNA addition. Ectopic expression of full-length G8P (G8PFL) or G8PPD in human cells can inactivate the genome-editing activity of SpyCas9 with minimum alterations of the mutation patterns. Furthermore, unlike the anti-CRISPR protein AcrII4A that completely abolishes the cellular activity of CRISPR-Cas9, G8P co-transfection can reduce the off-target activity of co-transfected SpCas9 while retaining its on-target activity. CONCLUSION: G8Ps discovered in the current study represent the first anti-CRISPR peptides that can allosterically inactivate CRISPR-Cas9. This finding may provide insights into developing next-generation CRISPR-Cas inhibitors for precision genome engineering.


Assuntos
Proteína 9 Associada à CRISPR/antagonistas & inibidores , Sistemas CRISPR-Cas , Fragmentos de Peptídeos/metabolismo , Regulação Alostérica , Bacteriófago M13 , Proteína 9 Associada à CRISPR/metabolismo , Proteínas do Capsídeo/química , Edição de Genes/métodos , Células HEK293 , Humanos , Células K562 , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética
20.
Adv Sci (Weinh) ; 6(23): 1901551, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832315

RESUMO

Using (hetero)aryl fluorosulfonates as versatile electrophiles, facile on-DNA cross-coupling reactions of Suzuki, Sonogashira, and Buchwald are reported here. Notably, all of these reactions show excellent functional group tolerance, mild reaction conditions (relative low temperature and open to air), rich heterocyclic coupling partners, and more importantly, DNA-compatibility. Thus, these new reactions based on efficient formation of C(sp2)-C(sp2), C(sp2)-C(sp), and C(sp2)-N bonds are highly amenable to synthesis of DNA-encoded libraries with great molecular diversity.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...