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1.
Exp Cell Res ; 435(2): 113949, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38266865

RESUMO

HECW1 belongs to ubiquitin ligase (E3) HECT family, and is found to be involved in tumorigenesis and tumor progression. However, the function of HECW1 in cervical cancer (CC) remains unknown. Clinical analysis showed that HECW1 is significantly decreased in CC tumor tissues. Ectopic expression of HECW1 suppressed cell growth, promoting cell cycle arrest and apoptosis in CC cells, while downregulation of HECW1 reversed these trends, impeded proliferation and accelerated cell cycle progression of CC cells. Overexpressing of HECW1 reduced mitochondrial membrane potential and the protein expression of voltage-dependent anion channel 1 (VDAC1). In addition, upregulation of HECW1 inhibited nuclear ß-catenin accumulation, downregulated ß-catenin/TCF/LEF-mediated transcriptional activity and the expression of downstream gene c-Myc, whereas inhibition of HECW1 received opposite results. Further results confirmed HECW1 affects the protein expression of dishevelled-1 (DVL1), a potent activator of Wnt/ß-catenin, and inhibition of HECW1 inhibited the ubiquitination of DVL1, upregulating its expression. Inhibition of DVL1 restrained the promotion effect of HECW1 suppression on cell proliferation. In vivo experiments also verified that HECW1 suppression promoted the tumor formation of CC cells. Summary, we demonstrated that HECW1 inhibits CC cell proliferation and tumor formation by downregulating DVL1 induced Wnt/ß-catenin signaling pathway activation.


Assuntos
Neoplasias do Colo do Útero , Via de Sinalização Wnt , Feminino , Humanos , Via de Sinalização Wnt/genética , Linhagem Celular Tumoral , Neoplasias do Colo do Útero/patologia , beta Catenina/genética , beta Catenina/metabolismo , Ubiquitinação , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteínas do Tecido Nervoso/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
Physiol Genomics ; 55(1): 1-15, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36314369

RESUMO

Long noncoding RNA (lncRNA) cardiac mesoderm enhancer-associated noncoding RNA (CARMN) is a newly discovered tumor-suppressor lncRNA in cancers. However, its role in cervical cancer (CC) remains elusive. This study was conducted to analyze the molecular mechanism of CARMN in CC cell growth and provide a novel theoretical basis for CC treatment. RT-qPCR and clinical analysis revealed that CARMN and B-cell translocation gene 2 (BTG2) were downregulated, whereas miR-92a-3p was upregulated in CC tissues and cells and their expressions were correlated with clinicopathological characteristics and prognosis. MTT assay, flow cytometry, and Transwell assays revealed that CARMN overexpression reduced proliferation, migration, and invasion and increased apoptosis rate in CC cells. Mechanically, CARMN repressed miR-92a-3p to promote BTG2 transcription. Functional rescue assays revealed that miR-92a-3p overexpression or BTG2 downregulation reversed the inhibitory role of CARMN overexpression in CC cell growth. Western blot analysis elicited that Wnt3a and ß-catenin were elevated in CC cells and CARMN blocked the Wnt/ß-catenin signaling pathway via the miR-92a-3p/BTG2 axis. Overall, our findings demonstrated that CARMN repressed miR-92a-3p to upregulate BTG2 transcription and then blocked the Wnt/ß-catenin signaling pathway, thereby suppressing CC cell growth.


Assuntos
Proteínas Imediatamente Precoces , MicroRNAs , RNA Longo não Codificante , Neoplasias do Colo do Útero , Via de Sinalização Wnt , Feminino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas Imediatamente Precoces/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética , Via de Sinalização Wnt/genética
3.
J Am Chem Soc ; 145(11): 6577-6584, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36916174

RESUMO

Parallel two molecular bridges loaded with a palladium catalyst were integrated into separate pairs of graphene electrodes in the same device. Based on the complete description of the one-palladium catalytic pathway by single-molecule electrical spectroscopy, this setup enables the mapping of the cross-correlation between different catalysts and demonstrates the emergent complexity in the extrapolation from single molecule to ensemble. The anticorrelation behaviors at the time scale of two individual catalysts in sufficiently close proximity were revealed in the Suzuki-Miyaura cross-coupling. Further experimental evidence demonstrates that the long-range electric dipole-dipole interaction induced by solvent leads to the destructive interferometric effect of two catalysts. In contrast, the cooperative coupling of the elementary step between two catalysts affords a local acceleration. This new form of reaction dynamics measurement via focusing on multiple molecules with single-event resolution holds great promise to build a bridge between single molecule and ensemble.

4.
J Virol ; 96(17): e0090722, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36000844

RESUMO

The rapid global emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused serious health problems, highlighting the urgent need for antiviral drugs. The viral main protease (Mpro) plays an important role in viral replication and thus remains the target of choice for the prevention or treatment of several viral diseases due to high sequence and structural conservation. Prolonged use of viral protease inhibitors can lead to the development of mutants resistant to those inhibitors and to many of the available antiviral drugs. Here, we used feline infectious peritonitis virus (FIPV) as a model to investigate its development of resistance under pressure from the Mpro inhibitor GC376. Passage of wild-type (WT) FIPV in the presence of GC376 selected for a mutation in the nsp12 region where Mpro cleaves the substrate between nsp12 and nsp13. This mutation confers up to 3-fold resistance to GC376 and nirmatrelvir, as determined by EC50 assay. In vitro biochemical and cellular experiments confirmed that FIPV adapts to the stress of GC376 by mutating the nsp12 and nsp13 hydrolysis site to facilitate cleavage by Mpro and release to mediate replication and transcription. Finally, we demonstrate that GC376 cannot treat FIP-resistant mutants that cause FIP in animals. Taken together, these results suggest that Mpro affects the replication of coronaviruses (CoVs) and the drug resistance to GC376 by regulating the amount of RdRp from a distant site. These findings provide further support for the use of an antiviral drug combination as a broad-spectrum therapy to protect against contemporary and emerging CoVs. IMPORTANCE CoVs cause serious human infections, and antiviral drugs are currently approved to treat these infections. The development of protease-targeting therapeutics for CoV infection is hindered by resistance mutations. Therefore, we should pay attention to its resistance to antiviral drugs. Here, we identified possible mutations that lead to relapse after clinical treatment of FIP. One amino acid substitution in the nsp12 polymerase at the Mpro cleavage site provided low-level resistance to GC376 after selection exposure to the GC376 parental nucleoside. Resistance mutations enhanced FIPV viral fitness in vitro and attenuated the therapeutic effect of GC376 in an animal model of FIPV infection. Our research explains the evolutionary characteristics of coronaviruses under antiviral drugs, which is helpful for a more comprehensive understanding of the molecular basis of virus resistance and provides important basic data for the effective prevention and control of CoVs.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Coronavirus Felino , Farmacorresistência Viral , Mutação , Inibidores de Proteases , Animais , Antivirais/farmacologia , Gatos/virologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/metabolismo , Coronavirus Felino/efeitos dos fármacos , Coronavirus Felino/enzimologia , Coronavirus Felino/genética , Farmacorresistência Viral/genética , Inibidores de Proteases/farmacologia
5.
Molecules ; 28(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38067610

RESUMO

Blocking the interaction between programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) by directly targeting the PD-L1 dimer has emerged as a hot topic in the field of cancer immunotherapy. Epigallocatechin gallate (EGCG), a natural product, has been demonstrated binding to the PD-L1 dimer in our previous study, but has a weaker binding capacity, moreover, EGCG is located at the end of the binding pocket of the PD-L1 dimer. The inhibitor fragment 1 (FRA) lies at the other end. So, we proposed that the introduction of FRA might be able to improve the binding ability. To illuminate this issue, molecular dynamics (MD) simulation was performed in the present study. Binding free energy calculations show that the binding affinity is significantly increased by 17 kcal/mol upon the introduction of FRA. It may be due to the energy contributions of emerging key residues ATyr56, AMet115, BTyr123, AIle54 and the enhanced contributions of initial key residues ATyr123 and BVal68. Binding mode and non-bonded interaction results indicate that FRA_EGCG (EGCG in combination with FRA) binds to the C-, F- and G-sheet of the PD-L1 dimer. Importantly, the introduction of FRA mainly strengthened the nonpolar interactions. The free energy landscape and secondary structure results further show that FRA_EGCG can interact with the PD-L1 dimer more stably. These data demonstrated here provide the theoretical basis for screening two or more natural products with additive inhibitory effect on this pathway and therefore exerting more effective anticancer immunity.


Assuntos
Catequina , Simulação de Dinâmica Molecular , Antígeno B7-H1/metabolismo , Catequina/farmacologia , Catequina/química , Estrutura Secundária de Proteína
6.
J Am Chem Soc ; 144(7): 3146-3153, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35038385

RESUMO

An accurate single-molecule kinetic isotope effect (sm-KIE) was applied to circumvent the inherent limitation of conventional ensemble KIE by using graphene-molecule-graphene single-molecule junctions. In situ monitoring of the single-molecule reaction trajectories in real time with high temporal resolution has the capability to characterize the deeper information brought by KIE. The C-O bond cleavage and the C-C bond formation of the transition state (TS) were observed in the Claisen rearrangement through the secondary kinetic isotope effect, demonstrating the high detection sensitivity and accuracy of this method. More interestingly, this sm-KIE can be used to determine TS structures under different electric fields, revealing the multidimensional regulation of the TS. The detection and manipulation of the TS provide a broad perspective to understand and optimize chemical reactions and biomimetic progress.

7.
Opt Express ; 30(22): 40251-40264, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298961

RESUMO

A highly sensitive optical fiber Mach-Zehnder interference curvature sensor based on MMF-GIMMF-MMF, which was made by sandwiching the graded-index multimode fiber (GIMMF) between two pieces of very short stepped-index multimode fibers (SIMMFs) spliced with input-single-mode fiber (SMF) and output-SMF, respectively, was proposed. The core diameter of the SIMMFs and GIMMF was 105 µm and 50 µm, respectively, and cladding diameter of them were both 125 µm. The sensing principle of the MMF-GIMMF- MMF sensors and the influences of structure parameters on the interference spectrum characteristics were theoretically analyzed in detail. Experimental results showed that when the length of the GIMMF was short enough (usually ≤ 10 mm), interference spectrum was induced by the interaction between the core modes and the low-order cladding modes due to the special structure of the designed Mach-Zehnder interferometer. Intensity of the interference valleys was highly sensitive to the applied bending but nearly independent of the surrounding temperature, on the contrary, the dip wavelength showed negligible sensitivity to the applied bending but relatively high temperature sensitivity. Thus, a temperature- independent curvature sensor could be realized by tracing the intensity variation of interference valley. In addition, different interference valley exhibited different intensity-based curvature sensitivity, providing more options for curvature sensing applications. Especially, total length of the sensor could be as short as 3 mm with length of GIMMF and SIMMFs only 1mm, the maximum curvature sensitivity could reach up to -78.75 dB/m-1 in the small curvature range of 0-2.36 m-1. Owing to its compact size, easy fabrication, good reproducibility and low cost, the proposed sensor is promising for bending-related high-precision engineering applications.

8.
FASEB J ; 35(3): e21350, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33629764

RESUMO

African swine fever (ASF) is an acute, hemorrhagic, and highly contagious disease caused by African swine fever virus (ASFV). The mortality rate of acute infection up to 100% have posed an unprecedented challenge of the swine industry. Currently no commercial antiviral drug is available for the control and treatment of ASFV. The structural resolution of ASFV virions reveals the details of ASFV morphogenesis, providing a new perspective for the research and promotion of the development of ASFV vaccines. Although the architecture of ASFV have been solved via cryo-EM, the structural details of four of the five viral layers remain unclear (except the outer capsid). In this study, we resolved the crystal structure of the ASFV core shell protein p15. The secondary structural elements of a protomer include four α-helix structures and six antiparallel ß-strands. Further analysis revealed that ASFV p15 forms disulfide-linked trimers between the Cys9 from one protomer and Cys30 from other protomer. Additionally, the nucleic acid-binding property was characterized by electrophoretic mobility shift assay. Two critical amino acid Lys10 and Lys39 have been identified which is essential to the nucleic acid-binding affinity of ASFV p15. Together, these findings may provide new insight into antiviral drug development.


Assuntos
Vírus da Febre Suína Africana/fisiologia , Proteínas Virais/química , Vírus da Febre Suína Africana/química , Cristalização , DNA/metabolismo , Multimerização Proteica , Proteínas Virais/fisiologia , Montagem de Vírus
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(5): 494-498, 2022 May 10.
Artigo em Zh | MEDLINE | ID: mdl-35598264

RESUMO

OBJECTIVE: To analyze clinical phenotype and genetic variants in a Chinese pedigree of hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome. METHODS: Whole exome sequencing was carried out for the proband from the pedigree. Suspected FH gene variants were validated by Sanger sequencing. Clinical manifestation and histopathological examination were used to analyze the pedigree comprehensively. RESULTS: The pedigree met the clinical diagnostic criteria for HLRCC syndrome. The whole exome sequencing showed that the FH gene of the proband had a heterozygous missense variant of c.1490T>C (p.F497S), which was consistent with the Sanger sequencing. The mother, daughter and son of the proband all had the heterozygous missense variant of c.1490T>C (p.F497S). According to the American Society of Medical Genetics and Genomics Classification Standards and Guidelines for Genetic Variations, c.1490T>C (p.F497S) (PM2+PP1-M+PP3+PP4) was a possible pathogenic variant. Based on our literature search, this variant was a new variant that had not been reported. CONCLUSION: The FH gene missense variant of c.1490T>C (p.F497S) may be the cause of the HLRCC syndrome pedigree, which provides a basis for the genetic diagnosis and genetic counseling of the HLRCC syndrome.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Leiomiomatose , Carcinoma de Células Renais/genética , Humanos , Neoplasias Renais/genética , Leiomiomatose/genética , Leiomiomatose/patologia , Mutação , Síndromes Neoplásicas Hereditárias , Linhagem , Fenótipo , Neoplasias Cutâneas , Neoplasias Uterinas
10.
Carcinogenesis ; 41(7): 961-971, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-31593983

RESUMO

Ecotropic viral integration site 1 (EVI1) is an oncogenic transcription factor, which is abnormally expressed in myeloid leukemia and other several solid cancers. It is associated with short survival as well as anticancer drug resistance. Autophagy is a protective mechanism that promotes cancer cell growth and survival under stressed conditions including clinical drug treatment. Here evidences are provided that EVI1 induces autophagy and mediated drug resistance in myeloid leukemia cells. Both knockdown using RNAi and pharmacological inhibition of autophagy significantly increase sensitivity to cytotoxic drug treatment in EVI1high cells. Mechanistic studies revealed that EVI1 regulated autophagy by directly binding to autophagy-related gene autophagy related 7 (ATG7) promoter and transcriptionally upregulating its expression. Notably, ATG7 expression was positively correlated with EVI1 in bone marrow mononuclear cells from myeloid leukemia patients. Acute myeloid leukemia patients with high level of EVI1 are associated with unfavorable overall survival, which was aggravated by simultaneous high expression of ATG7 in these patients. Furthermore, ChIP and firefly luciferase reporter assay identified an EVI1-binding site at 227 upstream promoter region of ATG7 which regulated its transcription. In addition, enforced expression of EVI1 also increased intracellular reactive oxygen species and ATG7 mRNA levels as well as autophagy activity, whereas the increase was attenuated after treatment with reactive oxygen species scavenger, suggesting the involvement of reactive oxygen species in EVI1-induced autophagy. These findings demonstrate that EVI protects myeloid leukemia cell from anticancer drug treatment by inducing autophagy through dual control of ATG7. These results might present a new therapeutic approach for improving treatment outcome in myelogenous leukemia with EVI1high.


Assuntos
Proteína 7 Relacionada à Autofagia/genética , Autofagia/genética , Leucemia Mieloide/tratamento farmacológico , Proteína do Locus do Complexo MDS1 e EVI1/genética , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Masculino , Regiões Promotoras Genéticas/genética
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(6): 547-551, 2019 Jun 10.
Artigo em Zh | MEDLINE | ID: mdl-31055802

RESUMO

OBJECTIVE: To explore the prevalence and characteristics of chromosomal abnormalities in abortuses during early pregnancy with single nucleotide polymorphism microarray (SNP-array). METHODS: For 520 abortuses, copy number variations (CNVs) in chorionic villi were analyzed with SNP-array. RESULTS: In 510 (98.1%) of the samples, the analysis was successful. Among these, 57.6% (294/510) of the samples were found to harbor clinically significant chromosomal abnormalities. 38.8% of the samples (198/510) had a normal result. 2.4% (12/510) of the samples harbored benign CNVs, and 1.2% (6/510) harbored variants of uncertain significance (VOUS). Aneuploidies, polyploidies, pathogenic CNVs and uniparental disomies (UPD) had accounted for 75.2% (221/294), 13.9% (41/294), 8.2% (24/294), and 2.7% (8/294) of the samples, respectively. 45,XO was the most common finding, which was followed by trisomy 16 and trisomy 22. 69,XXY was the most common polyploidy. CONCLUSION: Chromosomal abnormalities are the main cause for early miscarriage, among which aneuploidies are most common. The prevalence of aneuploidies is significantly increased among women over 35. SNP-array analysis has the advantage of high success rate, high resolution and great accuracy, but the clinical significance of microdeletions/microduplications found by SNP-array can be difficult for interpretation.


Assuntos
Vilosidades Coriônicas , Transtornos Cromossômicos , Aberrações Cromossômicas , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos , Humanos , Cariotipagem , Polimorfismo de Nucleotídeo Único , Gravidez
12.
Can J Microbiol ; 64(5): 327-337, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29401402

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease that is difficult to cure, with rising incidence in recent decades. Probiotics have become a new strategy for UC treatment. In this study, we chose 2 new multisource probiotics, Lactobacillus plantarum ZDY2013 from acid beans and Bifidobacterium bifidum WBIN03 from infant feces, and a mixture of both, to investigate the anti-inflammatory and antioxidant effect on H2O2-induced oxidative damage in a HT-29 cell model and dextran sodium sulfate (DSS)-induced UC in mice. Compared with the model group, the general relative indices results showed L. plantarum ZDY2013 and B. bifidum WBIN03 have a significant effect on DSS-induced UC in mice, by downregulating the pro-inflammatory cytokines (e.g., TNF-α) and upregulating antioxidant factors (e.g., SOD1, SOD2, GPX2) at the transcriptional level. By means of high-throughput sequencing (16S V3-V4) and systematical bioinformatics analyses, we found that colitis may be associated with the changes in intestinal flora, especially Firmicutes and Bacteroides. Administration of L. plantarum ZDY2013 increased the abundance of Lactobacillus animalis, whereas B. bifidum WBIN03 increased the abundance of Lachnospiraceae bacterium COE1. Our results revealed that a supplement of L. plantarum ZDY2013 and B. bifidum WBIN03 remit UC through modification of gut microbiota to regulate oxidative stress and inflammatory mediators.


Assuntos
Bifidobacterium bifidum/fisiologia , Colite/terapia , Microbioma Gastrointestinal , Lactobacillus plantarum/fisiologia , Probióticos/uso terapêutico , Animais , Colite/imunologia , Colite/microbiologia , Citocinas/metabolismo , Fezes/microbiologia , Feminino , Células HT29 , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo
13.
Molecules ; 23(7)2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973488

RESUMO

Inflammatory bowel disease (IBD) is a common disease characterized by chronic inflammation in gastrointestinal tracts, which is primarily treated by administering anti-inflammatory and immunosuppressive drugs that inhibit the burden of intestinal inflammation and improve disease-related symptoms. However, the established therapeutic strategy has limited therapeutic efficacy and adverse drug reactions. Therefore, new disease-targeting drug-delivery strategies to develop more effective treatments are urgent. This review provides an overview of the drug-targeting strategies that can be used to treat IBD, and our recent attempts on the colon-specific delivery system (Pae-SME-CSC) with a paeonol-loaded self-microemulsion (Pae-SMEDDS) are introduced.


Assuntos
Acetofenonas/química , Anti-Inflamatórios/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Administração Oral , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Colo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos
14.
Angew Chem Int Ed Engl ; 56(14): 4015-4019, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28267264

RESUMO

An efficient yttrium-catalyzed intramolecular hydroalkoxylation/Claisen rearrangement sequence has been achieved, thus enabling facile access to a diverse array of valuable medium-sized lactams. Furthermore, a mechanistic rationale for this novel cascade reaction is well supported by a variety of control experiments.

15.
Cancer Biother Radiopharm ; 39(1): 35-45, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181185

RESUMO

With the development of the social economy and the deepening understanding of cancer, cancer has become a significant cause of death, threatening human health. Although researchers have made rapid progress in cancer treatment strategies in recent years, the overall survival of cancer patients is still not optimistic. Therefore, it is essential to reveal the spatial pattern of gene expression, spatial heterogeneity of cell populations, microenvironment interactions, and other aspects of cancer. Spatiotemporal transcriptomics can help analyze the mechanism of cancer occurrence and development, greatly help precise cancer treatment, and improve clinical prognosis. Here, we review the integration strategies of single-cell RNA sequencing and spatial transcriptomics data, summarize the recent advances in spatiotemporal transcriptomics in cancer studies, and discuss the combined application of spatial multiomics, which provides new directions and strategies for the precise treatment and clinical prognosis of cancer.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Perfilação da Expressão Gênica , Neoplasias/genética , Neoplasias/terapia , Microambiente Tumoral/genética
16.
JACS Au ; 4(4): 1278-1294, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38665639

RESUMO

Molecules, with structural, scaling, and interaction diversities, are crucial for the emergence of complex behaviors. Interactions are essential prerequisites for complex systems to exhibit emergent properties that surpass the sum of individual component characteristics. Tracing the origin of complex molecular behaviors from interactions is critical to understanding ensemble emergence, and requires insights at the single-molecule level. Electrical signals from single-molecule junctions enable the observation of individual molecular behaviors, as well as intramolecular and intermolecular interactions. This technique provides a foundation for bottom-up explorations of emergent complexity. This Perspective highlights investigations of various interactions via single-molecule junctions, including intramolecular orbital and weak intermolecular interactions and interactions in chemical reactions. It also provides potential directions for future single-molecule junctions in complex system research.

17.
Int Immunopharmacol ; 137: 112523, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909500

RESUMO

BACKGROUND: APLNR is a G protein-coupled receptor and our previous study had revealed that APLNR could inhibit nasopharyngeal carcinoma (NPC) growth and metastasis. However, the role of APLNR in regulating PD-L1 expression and immune escape in NPC is unknown. METHODS: We analyzed the expression and correlation of APLNR and PD-L1 in NPC tissues and cells. We investigated the effect of APLNR on PD-L1 expression and the underlying mechanism in vitro and in vivo. We also evaluated the therapeutic potential of targeting APLNR in combination with PD-L1 antibody in a nude mouse xenograft model. RESULTS: We found that APLNR was negatively correlated with PD-L1 in NPC tissues and cells. APLNR could inhibit PD-L1 expression by binding to the FERM domain of JAK1 and blocking the interaction between JAK1 and IFNGR1, thus suppressing IFN-γ-mediated activation of the JAK1/STAT1 pathway. APLNR could also inhibit NPC immune escape by enhancing IFN-γ secretion and CD8+ T-cell infiltration and reducing CD8+ T-cell apoptosis and dysfunction. Moreover, the best effect was achieved in inhibiting NPC growth in nude mice when APLNR combined with PD-L1 antibody. CONCLUSIONS: Our study revealed a novel mechanism of APLNR regulating PD-L1 expression and immune escape in NPC and suggested that APLNR maybe a potential therapeutic target for NPC immunotherapy.

18.
Mol Ther Nucleic Acids ; 34: 102037, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37808922

RESUMO

Protein is an essential component of all living organisms and is primarily responsible for life activities; furthermore, its synthesis depends on a highly complex and accurate translation system. For proteins, the regulation at the translation level exceeds the sum of that during transcription, mRNA degradation, and protein degradation. Therefore, it is necessary to study regulation at the translation level. Imbalance in the translation process may change the cellular landscape, which not only leads to the occurrence, maintenance, progression, invasion, and metastasis of cancer but also affects the function of immune cells and changes the tumor microenvironment. Detailed analysis of transcriptional and protein atlases is needed to better understand how gene translation occurs. However, a more rigorous direct correlation between mRNA and protein levels is needed, which somewhat limits further studies. Translatomics is a technique for capturing and sequencing ribosome-related mRNAs that can effectively identify translation changes caused by ribosome stagnation and local translation abnormalities during cancer occurrence to further understand the changes in the translation landscape of cancer cells themselves and immune cells in the tumor microenvironment, which can provide new strategies and directions for tumor treatment.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37526191

RESUMO

OBJECTIVE: The present study aimed to investigate the therapeutic mechanism of Hedyotis diffusa Willd (HDW) and Scutellaria barbata (SB) in ccRCC using a combination of single-cell RNA sequencing (scRNA-seq) and network pharmacology. METHODS: The active ingredients and potential molecular targets of HDW-SB were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. Gene expression data (GSE53757) were obtained from the Gene Expression Omnibus database. The hub genes of HDW-SB against ccRCC were identified via the protein-protein interaction network, and further analyzed by molecular complex detection. The roles of these genes in the diagnosis and immune infiltration of ccRCC were analyzed. The clinical significance of hub genes was verified using scRNA-seq data (GSE121638) and molecular docking. RESULTS: Following the PPI network analysis, 29 hub genes of HDW-SB against ccRCC were identified. All hub genes, except for CENPE, had significantly different expressions in tumor tissue and a more accurate diagnosis of ccRCC. Fifteen cell clusters were defined based on the scRNA-seq dataset, and the clusters were annotated as six cell types using marker genes. TYMS and KIAA0101 from hub genes were highly expressed in NK cells. Three active compounds, quercetin, luteolin, and baicalein, were found to target TYMS and KIAA0101 from the compound-target interaction network. CONCLUSION: 29 hub genes of HDW-SB against ccRCC were identified and showed good performance in terms of diagnosis and prognosis. Moreover, among these hub genes docking with the main ingredients of HDW-SB, TYMS and KIAA0101 exerted anti-ccRCC effects through NK cells.

20.
Nat Protoc ; 18(6): 1958-1978, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37045993

RESUMO

The ability to measure the behavior of a single molecule during a reaction implies the detection of inherent dynamic and static disordered states, which may not be represented when measuring ensemble averages. Here, we describe the building of devices with graphene-molecule-graphene single-molecule junctions integrated into an electrical circuit. These devices are simple to build and are stable, showing tolerance to mechanical changes, solution environment and voltage stimulation. The design of a conductive channel based on a single molecule enables single-molecule detection and is sensitive to variations in physical properties and chemical structures of the detected molecules. The on-chip setup of single-molecule junctions further offers complementary metal-oxide-semiconductor (CMOS) compatibility, enabling logic functions in circuit elements, as well as deciphering of reaction intermediates. We detail the experimental procedure to prepare graphene transistor arrays as a basis for single-molecule junctions and the preparation of nanogapped carboxyl-terminal graphene electrodes by using electron-beam lithography and oxygen plasma etching. We describe the basic design of a molecular bridge with desired functions and terminals to form covalent bonds with electrode arrays, via a chemical reaction, to construct stably integrated single-molecule devices with a yield of 30-50% per chip. The immobilization of the single molecules is then characterized by using inelastic electron tunneling spectra, single-molecule imaging and fluorescent spectra. The whole protocol can be implemented within 2 weeks and requires users trained in using ultra-clean laboratory facilities and the aforementioned instrumentation.


Assuntos
Grafite , Grafite/química , Nanotecnologia/métodos , Eletrodos , Análise de Sequência com Séries de Oligonucleotídeos , Eletrônica
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