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In the emerging Sb2S3-based solar energy conversion devices, a CdS buffer layer prepared by chemical bath deposition is commonly used to improve the separation of photogenerated electron-hole pairs. However, the cation diffusion at the Sb2S3/CdS interface induces detrimental defects but is often overlooked. Designing a stable interface in the Sb2S3/CdS heterojunction is essential to achieve high solar energy conversion efficiency. As a proof of concept, this study reports that the modification of the Sb2S3/CdS heterojunction with an ultrathin Al2O3 interlayer effectively suppresses the interfacial defects by preventing the diffusion of Cd2+ cations into the Sb2S3 layer. As a result, a water-splitting photocathode based on Ag:Sb2S3/Al2O3/CdS heterojunction achieves a significantly improved half-cell solar-to-hydrogen efficiency of 2.78% in a neutral electrolyte, as compared to 1.66% for the control Ag:Sb2S3/CdS device. This work demonstrates the importance of designing atomic interfaces and may provide a guideline for the fabrication of high-performance stibnite-type semiconductor-based solar energy conversion devices.
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CONTEXT: Huangqi Guizhi Wuwu Decoction (HGWD) is effective in treating ischaemic stroke (IS). However, its mechanism of action is still unclear. OBJECTIVE: Network pharmacology integrated with in vivo experiments were used to clarify the underlying mechanisms of HGWD for treating IS. MATERIALS AND METHODS: TCMSP, GeneCards, OMIM and STRING were used to retrieve and construct visual protein interaction networks for the key targets. The AutoDock tool was used for molecular docking between key targets and active compounds. The neuroprotective effect of HGWD were verified in a middle cerebral artery occlusion (MCAO) model rat. The Sprague-Dawley (SD) rats were divided into sham, model, low-dose (5 g/kg, i.g.), high-dose (20 g/kg, i.g.), and nimodipine (20 mg/kg, i.g.) groups once daily for 7 days. The neurological scores, brain infarct volumes, lipid peroxidation, inflammatory cytokines, Nissl bodies, apoptotic neurons, and signalling pathways were all investigated and evaluated in vivo. RESULTS: Network pharmacology identified 117 HGWD targets related to IS and 36 candidate compounds. GO and KEGG analyses showed that HGWD anti-IS effects were mainly associated with PI3K-Akt and HIF-1 signalling pathways. HGWD effectively reduced the cerebral infarct volumes (19.19%), the number of apoptotic neurons (16.78%), and the release of inflammatory cytokines, etc. in MCAO rats. Furthermore, HGWD decreased the levels of HIF-1A, VEGFA, Bax, cleaved caspase-3, p-MAPK1, and p-c-Jun while increasing the expression of p-PI3K, p-AKT1, and Bcl-2. DISCUSSION AND CONCLUSION: This study initially elucidated the mechanism of HGWD anti-IS, which contributed to the further promotion and secondary development of HGWD in clinical practice.
Assuntos
Isquemia Encefálica , Medicamentos de Ervas Chinesas , AVC Isquêmico , Fármacos Neuroprotetores , Acidente Vascular Cerebral , Animais , Ratos , Ratos Sprague-Dawley , Farmacologia em Rede , Isquemia Encefálica/tratamento farmacológico , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinases , Acidente Vascular Cerebral/tratamento farmacológico , Citocinas , AVC Isquêmico/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêuticoRESUMO
Herein, a simple and facile one-step hydrothermal carbonization synthesis procedure for the fabrication of N, Cu-doped carbon quantum dots (N, Cu-CQDs) as a peroxidase-mimicking enzyme was reported. The peroxidase-like performance of N, Cu-CQDs was assessed based on the oxidative coupling reaction of phenol with 4-aminoantipyrine (4-AAP) in the presence of hydrogen peroxide (H2O2). The N, Cu-CQDs/4-AAP/H2O2 system was applied to sensing phenol based on double signals of absorption spectra (or colorimetric visualization) as well as fluorescence spectra. The obtained limits of detection (LODs) were as low as 0.12 µM and 0.02 µM, respectively. Moreover, the proposed method was successfully applied to the determination of phenol in sewage with satisfactory recovery. Our results demonstrate that the N, Cu-CQDs/4-AAP/H2O2/phenol sensing system has a great potential prospect for applications in environmental chemistry and biotechnology.
Assuntos
Pontos Quânticos , Carbono , Cobre , Peróxido de Hidrogênio , Nitrogênio , Peroxidases , Fenol , FenóisRESUMO
In this study, palladium/carbon dot composites (Pd-CDs) were fabricated via a facial hydrothermal route using ethanediamine and palladium chloride dihydrate as precursors. The obtained Pd-CDs showed an excellent intrinsic peroxidase-like activity, which could catalyze the oxidization of 3,3'5,5'-tetramethylbenzidine with the assistance of hydrogen peroxide (H2O2) and thus resulted in color change, accompanied by an absorption peak which appeared at 652 nm. Such response is H2O2 concentration-dependent and allows for the assay of H2O2 in the range of 0.1 to 30 µM with a limit of detection of 0.03 µM. Simultaneously, by combination of enzymatic oxidation of glucose with glucose oxidase and Pd-CD catalytic reaction, a colorimetric sensing platform was also constructed for glucose detection with high selectivity and sensitivity (limit of detection as low as 0.2 µM). Additionally, the proposed method exhibited capability for determination of glucose in real samples (fruit juice) with satisfactory recovery (98.5-103%), indicating potential application prospects in biochemical analysis.
Assuntos
Carbono/química , Glucose/análise , Peróxido de Hidrogênio/análise , Paládio/química , Benzidinas/química , Materiais Biomiméticos/química , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Limite de Detecção , Oxirredução , Peroxidase/químicaRESUMO
In this paper, we have presented a novel strategy to fabricate Fe-doped carbon quantum dots (Fe-CQDs) for dopamine sensing applications. The Fe-CQDs are obtained by one step hydrothermal carbonization, using ethylenediamine tetraacetic acid salts and ferric nitrate as the carbon and iron source, which simultaneously incorporates Fe (dopamine-bonding site) and luminescent carbon quantum dots (fluorophores). The added dopamine containing catechol groups might form complexes with Fe ions (doped in CQDs) due to coordination. Subsequently, dopamine was oxidized to generate dopamine-quinone (a known potent electron acceptor) species by ambient O2. Thus, the coordination induced dopamine in proximity to the CQDs, which provided favourable electron acceptors in close proximity to the CQDs and produced high quenching efficiencies. Such fluorescence responses can be used for well quantifying dopamine in the range of 0.01-50 µM with a detection limit of 5 nM (S/N = 3). The proposed sensing system has been successfully used for the assay of dopamine in human urine samples. Preliminary cell image study indicates that the obtained Fe-CQDs possess high photostability and low cytotoxicity, which make them promising for biological applications.
Assuntos
Dopamina/análise , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Carbono/química , Sobrevivência Celular/efeitos dos fármacos , Dopamina/urina , Feminino , Células HeLa , Humanos , Ferro/química , Limite de Detecção , Microscopia Confocal/métodos , Pontos Quânticos/toxicidade , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Using first-principles calculations, non-metallic doping at the Se site and metallic doping at the Sn site in a SnSe monolayer were systematically investigated. Our results showed that for non-metallic doping, the P atom acted as a highly promising p-type doping source due to its low formation energy and shallow acceptor level. However, n-type conductivity was predicted to be unfavorably realized with the substitution of F/Cl/Br atoms as they induced deep donor levels. For metallic doping, the Al atom introduced magnetism into the system and the optical absorption range was broadened due to dopant (Li, Mg, Al) modifications. These results were expected to provide a good reference for the realization of chemical doping in the SnSe monolayer.
RESUMO
A colorimetric assay is presented for the determination of ascorbic acid (AA). Manganese(II) doped carbon dots (Mn-CDs) were prepared by a convenient hydrothermal route and are shown to possess oxidase-like catalytic ability. They catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by dissolved oxygen to form a blue colored product (oxTMB). AA can reduce blue oxTMB to colorless TMB. The fading of the blue color (measured at 652 nm) can be applied for quantifying AA in the 50 to 2500 nM concentration range and with a 9 nM detection limit. The method was successfully used for the quantitation of AA in real samples. Graphical abstract Schematic representation of a colorimetric assay platform for the sensitive detection of ascorbic acid (AA) in view of inhibitory effect of AA on the 3,3',5,5'-tetramethylbenzidine (TMB) oxidation, benefitting from excellent oxidase-like catalytic activity of manganese(II) doped carbon dots (Mn-CDs).
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Ácido Ascórbico/sangue , Carbono/química , Colorimetria/métodos , Manganês/química , Pontos Quânticos/química , Ácido Ascórbico/química , Benzidinas/química , Catálise , Citrus sinensis/química , Corantes/química , Sucos de Frutas e Vegetais/análise , Humanos , Limite de Detecção , Oxirredução , Oxirredutases/química , Comprimidos/análiseRESUMO
Aberrant activation of cancer-derived mutants of the epidermal growth factor receptor (EGFR) is closely associated with cancer pathogenesis and is thought to be mediated through multiple tyrosine phosphorylations within the C-terminal domain. Here, we examined the consequences of the loss of these C-terminal phosphorylation sites on cellular transformation in the context of lung-cancer-derived L858R, exon 19 deletion and exon 20 insertion mutant EGFR. Oncogenic EGFR mutants with substitution of the 10 potential C-terminal tyrosine autophosphorylation sites for phenylalanine (CYF10) were still able to promote anchorage-independent growth in soft agar at levels comparable to the parental L858R or exon19 deletion or exon 20 insertion mutants with intact autophosphorylation sites. Furthermore, these CYF10 mutants retained the ability to transform Ba/F3 cells in the absence of IL-3. Bead-based phosphorylation and immunoprecipitation analyses demonstrated that key EGFR-associated proteins-including Grb2 and PLC-γ-are neither phosphorylated nor bound to CYF10 mutants in transformed cells. Taken together, we conclude that tyrosine phosphorylation is not required for oncogenic activity of lung-cancer-derived mutant EGFR, suggesting these mutants can lead to cellular transformation by an alternative mechanism independent of EGFR phosphorylation.
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Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Domínios Proteicos , Animais , Biomarcadores , Linhagem Celular , Receptores ErbB/química , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteína Adaptadora GRB2/genética , Proteína Adaptadora GRB2/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Camundongos , FosforilaçãoRESUMO
Van der Waals (vdW) heterostructures, which have the advantage of integrating excellent properties of the stacked 2D materials by vdW interactions, have gained increasing attention recently. In this work, within the framework of density functional theory calculations, the electronic properties of vdW heterostructure composed of phosphorene (BP) in black phosphorus phase and GeS monolayer are systematically explored. The results show that the carriers are not separated for both lattice-match and lattice-mismatch heterostructures. For the lattice-match heterostructure, it is found that changing monolayer of GeS to bilayer can increase the energy difference of valence band offsets between GeS and BP, thus realizing electron-hole separation. For the lattice-mismatch heterostructure, altering the layer distance can transform the heterostructure into a typical type-I alignment, but applying the electric field or doping with 2, 3, 5, 6-tetrafluoro-7, 7, 8, 8-tetracyanoquinodimethane (F4TCNQ) can make it display a perfect desirable type-II alignment, where holes migration and electrons transfer are revealed to account respectively for the phenomenon of carrier separation. It is believed that the work would greatly enlarge the potential application of the BP-based heterostructures in photoelectronics and further stimulate the investigation enthusiasms on other fashionable heterostructures and even unassuming heterostructures in which the charming electronic properties can be modulated to emerge by various general methods.
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Drug resistance presents a challenge to the treatment of cancer patients. Many studies have focused on cell-autonomous mechanisms of drug resistance. By contrast, we proposed that the tumour micro-environment confers innate resistance to therapy. Here we developed a co-culture system to systematically assay the ability of 23 stromal cell types to influence the innate resistance of 45 cancer cell lines to 35 anticancer drugs. We found that stroma-mediated resistance is common, particularly to targeted agents. We characterized further the stroma-mediated resistance of BRAF-mutant melanoma to RAF inhibitors because most patients with this type of cancer show some degree of innate resistance. Proteomic analysis showed that stromal cell secretion of hepatocyte growth factor (HGF) resulted in activation of the HGF receptor MET, reactivation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-OH kinase (PI(3)K)-AKT signalling pathways, and immediate resistance to RAF inhibition. Immunohistochemistry experiments confirmed stromal cell expression of HGF in patients with BRAF-mutant melanoma and showed a significant correlation between HGF expression by stromal cells and innate resistance to RAF inhibitor treatment. Dual inhibition of RAF and either HGF or MET resulted in reversal of drug resistance, suggesting RAF plus HGF or MET inhibitory combination therapy as a potential therapeutic strategy for BRAF-mutant melanoma. A similar resistance mechanism was uncovered in a subset of BRAF-mutant colorectal and glioblastoma cell lines. More generally, this study indicates that the systematic dissection of interactions between tumours and their micro-environment can uncover important mechanisms underlying drug resistance.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Fator de Crescimento de Hepatócito/metabolismo , Melanoma/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Microambiente Tumoral/fisiologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Linhagem Celular Tumoral , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteômica , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , VemurafenibRESUMO
Influenza A virus (IAV) infection is still a major global threat for humans, especially for the risk groups: young children and the elderly. The currently licensed antiviral drugs target viral factors and are prone to viral resistance. In recent years, a few endogenous small molecules from host, such as estradiol and omega-3 polyunsaturated fatty acid (PUFA)-derived lipid mediator protection D1 (PD1), were demonstrated to be capable of inhibiting IAV infection. Chenodeoxycholic acid (CDCA), one of the main primary bile acids, is synthesized from cholesterol in the liver and classically functions in emulsification and absorption of dietary fats. Clinically, CDCA has been used in the treatment of patients with cholesterol gallstones for more than five decades. In this study, we showed that CDCA attenuated the replication of three subtypes of influenza A virus, including a highly pathogenic H5N1 strain, in A549 and MDCK cell cultures with IC50 ranging from 5.5 to 11.5 µM. Mechanistically, CDCA effectively restrained the nuclear export of viral ribonucleoprotein (vRNP) complexes. In conclusion, as an endogenous physiological small molecule, CDCA can inhibit IAV replication in vitro, at least in part, by blocking vRNP nuclear export, and affords further studies for development as a potential antiviral agent against IAV infections.
Assuntos
Antivirais/farmacologia , Ácido Quenodesoxicólico/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Ribonucleoproteínas/metabolismo , Células A549 , Animais , Cães , Humanos , Células Madin Darby de Rim Canino , Replicação Viral/efeitos dos fármacosRESUMO
Understanding the molecular pathways by which oncogenes drive cancerous cell growth, and how dependence on such pathways varies between tumors could be highly valuable for the design of anti-cancer treatment strategies. In this work we study how dependence upon the canonical PI3K and MAPK cascades varies across HER2+ cancers, and define biomarkers predictive of pathway dependencies. A panel of 18 HER2+ (ERBB2-amplified) cell lines representing a variety of indications was used to characterize the functional and molecular diversity within this oncogene-defined cancer. PI3K and MAPK-pathway dependencies were quantified by measuring in vitro cell growth responses to combinations of AKT (MK2206) and MEK (GSK1120212; trametinib) inhibitors, in the presence and absence of the ERBB3 ligand heregulin (NRG1). A combination of three protein measurements comprising the receptors EGFR, ERBB3 (HER3), and the cyclin-dependent kinase inhibitor p27 (CDKN1B) was found to accurately predict dependence on PI3K/AKT vs. MAPK/ERK signaling axes. Notably, this multivariate classifier outperformed the more intuitive and clinically employed metrics, such as expression of phospho-AKT and phospho-ERK, and PI3K pathway mutations (PIK3CA, PTEN, and PIK3R1). In both cell lines and primary patient samples, we observed consistent expression patterns of these biomarkers varies by cancer indication, such that ERBB3 and CDKN1B expression are relatively high in breast tumors while EGFR expression is relatively high in other indications. The predictability of the three protein biomarkers for differentiating PI3K/AKT vs. MAPK dependence in HER2+ cancers was confirmed using external datasets (Project Achilles and GDSC), again out-performing clinically used genetic markers. Measurement of this minimal set of three protein biomarkers could thus inform treatment, and predict mechanisms of drug resistance in HER2+ cancers. More generally, our results show a single oncogenic transformation can have differing effects on cell signaling and growth, contingent upon the molecular and cellular context.
Assuntos
Sistema de Sinalização das MAP Quinases , Neoplasias/genética , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Biologia Computacional , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Genes erbB-2 , Humanos , Sistema de Sinalização das MAP Quinases/genética , Mutação , Neoplasias/patologia , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismoRESUMO
Microphthalmia-associated transcription factor (MITF) acts via pigment epithelium-derived factor (PEDF), an antiangiogenic protein, to regulate retinal pigment epithelium migration. PEDF expression and/or regulation during melanoma development have not been investigated previously. Using immunohistochemistry, we determined expression of PEDF in common and dysplastic melanocytic nevi, melanoma in situ, invasive melanoma, and metastatic melanoma (n = 102). PEDF expression was consistently decreased in invasive and metastatic melanoma, compared with nevi and melanoma in situ (P < 0.0001). PEDF was lost in thicker melanomas (P = 0.003), and correlated with depth of invasion (P = 0.003) and distant metastasis (P = 0.0331), but only marginally with mitotic index, AJCC stage, nodal metastasis, or blood vascular density (0.05 < P < 0.10). Quantitative real-time PCR and microarray analyses confirmed PEDF down-regulation at the mRNA level in several melanoma lines, compared with melanocytes. MITF positively correlated with PEDF expression in invasive melanomas (P = 0.0003). Searching for PEDF regulatory mechanisms revealed two occupied conserved E-boxes (DNA recognition elements) in the first intron of the human and mouse PEDF promoter regions, confirmed by binding assays. Dominant-negative and siRNA approaches in vivo demonstrated direct transcriptional influence of MITF on PEDF, establishing the PEDF gene (SERPINF1) as a MITF target in melanocytes and melanoma cells. These findings suggest that loss of PEDF expression promotes early invasive melanoma growth.
Assuntos
Proteínas do Olho/metabolismo , Regulação Neoplásica da Expressão Gênica , Melanoma/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Fatores de Crescimento Neural/metabolismo , Serpinas/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Linhagem Celular Tumoral , Feminino , Inativação Gênica , Humanos , Imuno-Histoquímica , Masculino , Melanócitos , Camundongos , Microscopia de Fluorescência , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , RNA Interferente Pequeno/metabolismo , Homologia de Sequência do Ácido Nucleico , Adulto JovemRESUMO
A novel and label-free fluorescence polarization (FP) method for the determination of pyrophosphate (PPi) is developed based on the change in FP signals during fast reversible transformation between CdTe zero-dimensional (0D) nanocrystals (NCs) and one-dimensional (1D) nanorods (NRs) induced by addition of PPi. Under optimum conditions, the FP ratio was linearly proportional to the logarithm of the concentration of PPi between 2.0 × 10(-5) and 1.0 × 10(-9) M with a detection limit of 8.0 × 10(-10) M. The developed method, with high signal selectivity and stability, was successfully applied to the detection of PPi in human urine samples.
Assuntos
Compostos de Cádmio/química , Difosfatos/urina , Polarização de Fluorescência/métodos , Nanopartículas/química , Nanotubos/química , Telúrio/química , Difosfatos/análise , Humanos , Limite de DetecçãoRESUMO
TSC1 is often mutated in bladder cancer. However the importance of this event in disease pathogenesis and its implications for therapy are uncertain. We used genomic sequencing to examine the involvement of TSC1 in bladder cancer, and signalling pathway analysis and small-molecule screening to identify targeted therapeutic strategies in TSC1 mutant bladder cancer cell lines. TSC1 loss of heterozygosity was seen in 54% of bladder cancers. Two (4.9%) of these 41 bladder cancers had TSC1 mutations by exon-based sequencing. Analysis of 27 bladder cancer cell lines demonstrated inactivating TSC1 mutations in three: RT-4, HCV29, 97-1. Interestingly, only RT-4 showed classic feedback inhibition of AKT, and was highly sensitive to treatment with mTOR inhibitors rapamycin and Torin1. 97-1 cells showed constitutive EGFR activation, and were highly sensitive to combined treatment with the mTOR inhibitor Torin1 and EGFR inhibitors Lapatinib or Afatinib. A BRAF missense mutation G469V was found in HCV29 cells, and AKT activation was dependent on BRAF, but independent of ERK. A kinase inhibitor screen of HCV29 cells showed strong growth inhibition by the Hsp90 inhibitor NVP-AUY922, and we then found synergistic inhibitory effects of NVP-AUY922 combined with either Torin1 or rapamycin on cell survival for both HCV29 and 97-1 cells. In aggregate, these findings indicate that there are highly variable mutation profiles and signalling pathway activation in TSC1-mutant bladder cancer. Furthermore, combined Hsp90/mTOR inhibition is a promising therapeutic approach for TSC1 mutant bladder cancer.
Assuntos
Quinazolinas/farmacologia , Transdução de Sinais/fisiologia , Sirolimo/farmacologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Bexiga Urinária , Afatinib , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Isoxazóis/farmacologia , Lapatinib , Perda de Heterozigosidade/genética , Naftiridinas/farmacologia , Fosforilação/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resorcinóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismoRESUMO
Although androgen receptor (AR)-mediated signaling is central to prostate cancer, the ability to modulate AR signaling states is limited. Here we establish a chemical genomic approach for discovery and target prediction of modulators of cancer phenotypes, as exemplified by AR signaling. We first identify AR activation inhibitors, including a group of structurally related compounds comprising celastrol, gedunin, and derivatives. To develop an in silico approach for target pathway identification, we apply a gene expression-based analysis that classifies HSP90 inhibitors as having similar activity to celastrol and gedunin. Validating this prediction, we demonstrate that celastrol and gedunin inhibit HSP90 activity and HSP90 clients, including AR. Broadly, this work identifies new modes of HSP90 modulation through a gene expression-based strategy.
Assuntos
Biomarcadores Tumorais/metabolismo , Expressão Gênica/efeitos dos fármacos , Genoma Humano , Proteínas de Choque Térmico HSP90/metabolismo , Receptores Androgênicos/metabolismo , Antibióticos Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Proteínas de Fusão bcr-abl/metabolismo , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Concentração Inibidora 50 , Lactamas Macrocíclicas/farmacologia , Limoninas/farmacologia , Masculino , Metribolona/farmacologia , Triterpenos Pentacíclicos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , RNA Mensageiro/análise , Reprodutibilidade dos Testes , Triterpenos/farmacologia , Tirosina Quinase 3 Semelhante a fms/metabolismoRESUMO
Clear cell sarcoma (CCS) harbors a pathognomonic chromosomal translocation fusing the Ewing's sarcoma gene (EWS) to the CREB family transcription factor ATF1 and exhibits melanocytic features. We show that EWS-ATF1 occupies the MITF promoter, mimicking melanocyte-stimulating hormone (MSH) signaling to induce expression of MITF, the melanocytic master transcription factor and an amplified oncogene in melanoma. Knockdown/rescue studies revealed that MITF mediates the requirement of EWS-ATF1 for CCS survival in vitro and in vivo as well as for melanocytic differentiation. Moreover, MITF and TFE3 reciprocally rescue one another in lines derived from CCS or pediatric renal carcinoma. Seemingly unrelated tumors thus employ distinct strategies to oncogenically dysregulate the MiT family, collectively broadening the definition of MiT-associated human cancers.
Assuntos
Fator 1 Ativador da Transcrição/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Fusão Oncogênica/fisiologia , Proteína EWS de Ligação a RNA/genética , Sarcoma de Células Claras/metabolismo , Fator 1 Ativador da Transcrição/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Grupo de Alta Mobilidade/biossíntese , Humanos , Hormônios Estimuladores de Melanócitos/fisiologia , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Nus , Fator de Transcrição Associado à Microftalmia/genética , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Regiões Promotoras Genéticas , Fatores de Transcrição de Fator Regulador X , Fatores de Transcrição SOXE , Sarcoma de Células Claras/patologia , Transdução de Sinais , Fatores de Transcrição/biossínteseRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Ischemic stroke is an acute central nervous system disease that poses a threat to human health. It induces a series of severe pathological mechanisms, ultimately leading to neuronal cell death in the brain due to local ischemia and hypoxia. Buyang Huanwu decoction (BYHWD), as a representative formula for treating ischemic stroke, has shown good therapeutic effects in stroke patients. AIM OF THE STUDY: This study aimed to explore the mechanism of BYHWD in promoting neural remodeling after ischemic stroke from the perspective of neuronal synaptic plasticity, based on the cAMP/PKA/CREB signaling pathway. MATERIALS AND METHODS: A modified suture technique was employed to establish a rat model of MCAO. The rats were divided into sham, model, and BYHWD (20 g/kg) groups. After the corresponding intervention, rat brains from each group were collected. TMT quantitative proteomics technology was employed for the research. Following proteomics studies, we investigated the mechanism of BYHWD in the intervention of ischemic stroke through animal experiments and cell experiments. The experimental animals were divided into sham, model, and BYHWD (5 g/kg, 10 g/kg, and 20 g/kg) groups. Infarct volume and severity of brain injury were measured by TTC staining. HE staining was utilized to evaluate alterations in tissue morphology. The Golgi staining was used to observe changes in cell body, dendrites, and dendritic spines. Transmission electron microscopy was used to observe the ultrastructure of synapses in the cortex and hippocampus. TUNEL staining was conducted to identify apoptotic neurons. Meanwhile, a stable and reliable (OGD/R) SH-SY5Y cell model was established. The effect of BYHWD-containing serum on SH-SY5Y cell viability was measured by CCK-8 kit. The apoptosis situation of SH-SY5Y cells was determined by Annexin V-FITC/PI. Immunofluorescence was employed to measure the fluorescence intensity of synaptic-related factors Syt1, Psd95, and Syn1. Synaptic plasticity pathways were assessed by using RT-qPCR and Western blot to determine the expression levels of cAMP, Psd95, Prkacb, Creb1/p-Creb1, BDNF, Shank2, Syn1, Syt1, Bcl-2, Bcl-2/Bax mRNA and proteins. RESULTS: After treatment with BYHWD, notable alterations were detected in the signaling pathways linked to synaptic plasticity and the cAMP signaling pathway-related targets among the intervention targets. This trend of change was also reflected in other bioinformatics analyses, indicating the important role of synaptic plasticity changes before and after modeling and drug intervention. The results of vivo and vitro experiments showed that BYHWD improved local pathological changes, and reduced cerebral infarct volume, and neurological function scores in MCAO rats. It increased dendritic spine density, improved synaptic structural plasticity, and had a certain neuroprotective effect. BYHWD increased the postsynaptic membrane thickness, synaptic interface curvature, and synaptic quantity. 10% BYHWD-containing serum was determined as the optimal concentration for treatment. 10% BYHWD-containing serum significantly reduced the overall apoptotic rate of (OGD/R) SH-SY5Y cells. Immunofluorescence experiments demonstrated that 10% BYHWD-containing serum could improve synaptic plasticity and increase the relative expression levels of synaptic-related proteins Syt1, Psd95, and Syn1. BYHWD and decoction-containing serum upregulated the mRNA and protein expression levels in (OGD/R) SH-SY5Y cells and MCAO rats, suggesting its ability to improve damaged neuronal synaptic plasticity and enhance transmission efficiency, which might be achieved through the regulation of the cAMP/PKA/CREB pathway. CONCLUSIONS: This study may provide a basis for clinical medication by elucidating the underlying experimental evidence for the promotion of neural plasticity after ischemic stroke by BYHWD.
RESUMO
Water-metal interaction has been receiving extensive attention due to its interdisciplinary application. In this paper, on the basis of first-principle calculations and slab models, the behavior of water adsorption and dissociation on planar, stepped and blocked Ni surfaces is investigated, the effects of steps, Au and Ag dopants, coverage and self-aggregation of water are also disclosed. The results show that: step not only strengthens water-substrate interaction but also facilitates water dissociation. With dopants modification, the adsorption and dissociation properties remain relatively unchanged at lower coverage (1/9 on facets and 1/12 ML on steps) while at higher coverage (1/4 on facets and 1/6 ML on steps) water adsorption is weakened and dissociation activity decreases dramatically. Water adsorption and dissociation properties on Ni surfaces are essentially unaffected with the increase of coverage. On doped surfaces, adsorption properties and dissociation activities are closely associated with the ligand effect, which is dependent on the dopant, dopant concentration and surface morphology. Water self-aggregation enhances water-surface interaction on all studied surfaces due to hydrogen bond (network) formation. Furthermore, investigation shows that it does not assist water dissociation.
RESUMO
BACKGROUND: Novel therapies are needed for the treatment of invasive thyroid cancers. Aberrant activation of tyrosine kinases plays an important role in thyroid oncogenesis. Because current targeted therapies are biased toward a small subset of tyrosine kinases, we conducted a study to reveal novel therapeutic targets for thyroid cancer using a bead-based, high-throughput system. METHODS: Thyroid tumors and matched normal tissues were harvested from twenty-six patients in the operating room. Protein lysates were analyzed using the Luminex immunosandwich, a bead-based kinase phosphorylation assay. Data was analyzed using GenePattern 3.0 software and clustered according to histology, demographic factors, and tumor status regarding capsular invasion, size, lymphovascular invasion, and extrathyroidal extension. Survival and invasion assays were performed to determine the effect of Src inhibition in papillary thyroid cancer (PTC) cells. RESULTS: Tyrosine kinome profiling demonstrated upregulation of nine tyrosine kinases in tumors relative to matched normal thyroid tissue: EGFR, PTK6, BTK, HCK, ABL1, TNK1, GRB2, ERK, and SRC. Supervised clustering of well-differentiated tumors by histology, gender, age, or size did not reveal significant differences in tyrosine kinase activity. However, supervised clustering by the presence of invasive disease showed increased Src activity in invasive tumors relative to non-invasive tumors (60% v. 0%, p<0.05). In vitro, we found that Src inhibition in PTC cells decreased cell invasion and proliferation. CONCLUSION: Global kinome analysis enables the discovery of novel targets for thyroid cancer therapy. Further investigation of Src targeted therapy for advanced thyroid cancer is warranted.