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1.
Neoplasma ; 70(2): 240-250, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37005955

RESUMO

Transcriptional adaptor 3 (TADA3/ADA3) is a conserved transcriptional co-activator and is dysregulated in many aggressive tumors. However, the role of TADA3 in non-small cell lung cancer (NSCLC) remains unknown. It was previously demonstrated that TADA3 expression correlates with poor prognosis in patients with NSCLC. In the present study, the expression and function of TADA3 were investigated in cells in vitro and in vivo. TADA3 expression was evaluated in clinical specimens and cell lines using reverse transcription-quantitative PCR and western blot analysis. The TADA3 protein level was significantly higher in human NSCLC specimens compared with matched normal tissues. In human NSCLC cell lines, short hairpin RNA-mediated silencing of TADA3 suppressed their proliferative, migratory and invasive abilities in vitro, and delayed G1 to S phase progression through the cell cycle. Consistent with this, TADA3 silencing increased expression of the epithelial marker E-cadherin and reduced expression of the mesenchymal markers, N-cadherin, Vimentin, Snail, and Slug. To verify the effect of TADA3 on tumor formation and growth in vivo, a mouse tumor xenograft model was established. TADA3 silencing slowed the growth of NSCLC tumor xenografts in nude mice, and excised tumors showed a similarly altered pattern of epithelial-mesenchymal transition (EMT) marker expression. The present results demonstrated the significance of TADA3 in regulating the growth and metastasis of NSCLC and may provide a theoretical basis for early diagnosis and targeted therapy of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Transição Epitelial-Mesenquimal/genética , Camundongos Nus , Fatores de Transcrição/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica
2.
J Asian Nat Prod Res ; 24(4): 321-327, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34009066

RESUMO

Three new lanostane triterpenoids, designated as 6-hydroxyl schiglausin A (1), 29-hydroxyl schiglausin D (2), and 6-hydroxyl schiglausin G (3), were isolated from the ethanol extract of the stems of Schisandra viridis. Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for cytotoxic activities. As a result, compound 1 exhibited cytotoxic activities for all six tested human lung cancer cell lines with IC50 values less than 10 µM.


Assuntos
Schisandra , Triterpenos , Linhagem Celular Tumoral , Etanol , Estrutura Molecular , Extratos Vegetais , Schisandra/química , Triterpenos/química , Triterpenos/farmacologia
3.
Appl Environ Microbiol ; 84(14)2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29728384

RESUMO

3-Ketosteroid 9α-hydroxylase (Ksh) consists of a terminal oxygenase (KshA) and a ferredoxin reductase and is indispensable in the cleavage of steroid nucleus in microorganisms. The activities of Kshs are crucial factors in determining the yield and distribution of products in the biotechnological transformation of sterols in industrial applications. In this study, two KshA homologues, KshA1N and KshA2N, were characterized and further engineered in a sterol-digesting strain, Mycobacterium neoaurum ATCC 25795, to construct androstenone-producing strains. kshA1N is a member of the gene cluster encoding sterol catabolism enzymes, and its transcription exhibited a 4.7-fold increase under cholesterol induction. Furthermore, null mutation of kshA1N led to the stable accumulation of androst-4-ene-3,17-dione (AD) and androst-1,4-diene-3,17-dione (ADD). We determined kshA2N to be a redundant form of kshA1N Through a combined modification of kshA1N, kshA2N, and other key genes involved in the metabolism of sterols, we constructed a high-yield ADD-producing strain that could produce 9.36 g liter-1 ADD from the transformation of 20 g liter-1 phytosterols in 168 h. Moreover, we improved a previously established 9α-hydroxy-AD-producing strain via the overexpression of a mutant KshA1N that had enhanced Ksh activity. Genetic engineering allowed the new strain to produce 11.7 g liter-1 9α-hydroxy-4-androstene-3,17-dione (9-OHAD) from the transformation of 20.0 g liter-1 phytosterol in 120 h.IMPORTANCE Steroidal drugs are widely used for anti-inflammation, anti-tumor action, endocrine regulation, and fertility management, among other uses. The two main starting materials for the industrial synthesis of steroid drugs are phytosterol and diosgenin. The phytosterol processing is carried out by microbial transformation, which is thought to be superior to the diosgenin processing by chemical conversions, given its simple and environmentally friendly process. However, diosgenin has long been used as the primary starting material instead of phytosterol. This is in response to challenges in developing efficient microbial strains for industrial phytosterol transformation, which stem from complex metabolic processes that feature many currently unclear details. In this study, we identified two oxygenase homologues of 3-ketosteroid-9α-hydroxylase, KshA1N and KshA2N, in M. neoaurum and demonstrated their crucial role in determining the yield and variety of products from phytosterol transformation. This work has practical value in developing industrial strains for phytosterol biotransformation.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Oxigenases de Função Mista/genética , Mycobacterium/genética , Mycobacterium/metabolismo , Esteroides/metabolismo , Substituição de Aminoácidos , Androstadienos/metabolismo , Biotransformação , Colesterol , Diosgenina/metabolismo , Deleção de Genes , Engenharia Genética/métodos , Redes e Vias Metabólicas/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/metabolismo , Oxigenases/metabolismo , Fitosteróis/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína
4.
Microb Cell Fact ; 16(1): 89, 2017 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-28532497

RESUMO

BACKGROUND: The strategy of modifying the sterol catabolism pathway in mycobacteria has been adopted to produce steroidal pharmaceutical intermediates, such as 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC), which is used to synthesize various steroids in the industry. However, the productivity is not desirable due to some inherent problems, including the unsatisfactory uptake rate and the low metabolic efficiency of sterols. The compact cell envelope of mycobacteria is a main barrier for the uptake of sterols. In this study, a combined strategy of improving the cell envelope permeability as well as the intracellular sterol metabolism efficiency was investigated to increase the productivity of 4-HBC. RESULTS: MmpL3, encoding a transmembrane transporter of trehalose monomycolate, is an important gene influencing the assembly of mycobacterial cell envelope. The disruption of mmpL3 in Mycobacterium neoaurum ATCC 25795 significantly enhanced the cell permeability by 23.4% and the consumption capacity of sterols by 15.6%. Therefore, the inactivation of mmpL3 was performed in a 4-HBC-producing strain derived from the wild type M. neoaurum and the 4-HBC production in the engineered strain was increased by 24.7%. Subsequently, to enhance the metabolic efficiency of sterols, four key genes, choM1, choM2, cyp125, and fadA5, involved in the sterol conversion pathway were individually overexpressed in the engineered mmpL3-deficient strain. The production of 4-HBC displayed the increases of 18.5, 8.9, 14.5, and 12.1%, respectively. Then, the more efficient genes (choM1, cyp125, and fadA5) were co-overexpressed in the engineered mmpL3-deficient strain, and the productivity of 4-HBC was ultimately increased by 20.3% (0.0633 g/L/h, 7.59 g/L 4-HBC from 20 g/L phytosterol) compared with its original productivity (0.0526 g/L/h, 6.31 g/L 4-HBC from 20 g/L phytosterol) in an industrial resting cell bio-transformation system. CONCLUSIONS: Increasing cell permeability combined with the co-overexpression of the key genes (cyp125, choM1, and fadA5) involved in the conversion pathway of sterol to 4-HBC was effective to enhance the productivity of 4-HBC. The strategy might also be useful for the conversion of sterol to other steroidal intermediates by mycobacteria.


Assuntos
Colestenonas/metabolismo , Genes Bacterianos , Mycobacterium/genética , Mycobacterium/metabolismo , Esteróis/química , Esteróis/metabolismo , Permeabilidade da Membrana Celular , Redes e Vias Metabólicas
5.
Bioinformatics ; 30(11): 1522-9, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24504871

RESUMO

MOTIVATION: Nucleosome positioning participates in many cellular activities and plays significant roles in regulating cellular processes. With the avalanche of genome sequences generated in the post-genomic age, it is highly desired to develop automated methods for rapidly and effectively identifying nucleosome positioning. Although some computational methods were proposed, most of them were species specific and neglected the intrinsic local structural properties that might play important roles in determining the nucleosome positioning on a DNA sequence. RESULTS: Here a predictor called 'iNuc-PseKNC' was developed for predicting nucleosome positioning in Homo sapiens, Caenorhabditis elegans and Drosophila melanogaster genomes, respectively. In the new predictor, the samples of DNA sequences were formulated by a novel feature-vector called 'pseudo k-tuple nucleotide composition', into which six DNA local structural properties were incorporated. It was observed by the rigorous cross-validation tests on the three stringent benchmark datasets that the overall success rates achieved by iNuc-PseKNC in predicting the nucleosome positioning of the aforementioned three genomes were 86.27%, 86.90% and 79.97%, respectively. Meanwhile, the results obtained by iNuc-PseKNC on various benchmark datasets used by the previous investigators for different genomes also indicated that the current predictor remarkably outperformed its counterparts. AVAILABILITY: A user-friendly web-server, iNuc-PseKNC is freely accessible at http://lin.uestc.edu.cn/server/iNuc-PseKNC.


Assuntos
Nucleossomos/química , Análise de Sequência de DNA/métodos , Animais , Caenorhabditis elegans/genética , DNA/química , Drosophila melanogaster/genética , Genoma , Genômica/métodos , Humanos , Nucleotídeos/análise , Software
6.
Metab Eng ; 24: 181-91, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24831710

RESUMO

3-Ketosteroid-△(1)-dehydrogenase (KstD) is a key enzyme involved in the microbial catabolism of sterols. Here, three homologues of KstD were characterized from Mycobacterium neoaurum ATCC 25795, showing distinct substrate preferences and transcriptional responses to steroids. Single deletion of any MN-kstD failed to result in a stable and maximum accumulation of 9-OHAD due to residual KstD activities. To develop stable 9-OHAD producers, all of these MN-KstDs were inactivated, which led to about 6.02g l(-1) of 9-OHAD from 15g l(-1) of phytosterols. However, the product was mixed with 1.55g l(-1) of AD as a major by-product. To transform AD, the oxygenase component of 3-ketosteroid-9α-hydroxylase (KSH), encoded by kshA, was overexpressed. As a result, the yield of 9-OHAD increased to 7.33g l(-1) with less than 0.31g l(-1) of AD and the selectivity of 9-OHAD production was improved to 95-97% among metabolites.


Assuntos
Androstenodiona/análogos & derivados , Proteínas de Bactérias , Oxigenases de Função Mista , Mycobacterium , Oxirredutases , Androstenodiona/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Mycobacterium/enzimologia , Mycobacterium/genética , Oxirredutases/genética , Oxirredutases/metabolismo , Fitosteróis/metabolismo
7.
Phytother Res ; 28(3): 372-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23610010

RESUMO

Total glycosides of peony (TGP) is a natural immuno-modulatory drug extracted from traditional Chinese herb peony. It has been approved by State Food and Drug Administration for the treatment of rheumatoid arthritis. However, data of TGP effect on psoriatic arthritis (PsA) is still scarce. In this study, 19 patients with PsA received 12-week treatment of TGP, and clinical efficacy in joint manifestations was evaluated by DAS28 at weeks 0, 4, 8 and 12. Peripheral percentages of Tregs, Th1, Th2 and NK cells were analyzed, and serum Th1-type cytokines (IL-12, IFN-γ and TNF-α), Th2-type cytokines (IL-4, IL-5 and IL-10) as well as pro-inflammatory factors (IL-2, IL-6 and IL-8) were concomitantly examined. Six patients (32%) exhibited ≥25% decrease of DAS28 (responders). Interestingly, all responders displayed a continuous decrease in Treg and Th1 numbers during TGP treatment, concomitant with significant decreases in Th1-type cytokine levels. Serum IL-6 also showed a significant decline in responders. Non-responders lacked these sequential alterations. Thus, TGP merits further consideration as a promising therapeutic option for PsA. The result indicated that recovery of Tregs and Th1 may serve as prognostic markers to assess responsiveness to TGP treatment in PsA.


Assuntos
Artrite Psoriásica/tratamento farmacológico , Glucosídeos/uso terapêutico , Paeonia/química , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Adulto , Feminino , Humanos , Interferon gama/imunologia , Interleucinas/imunologia , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/imunologia , Estados Unidos , Adulto Jovem
8.
Nat Commun ; 12(1): 4091, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215748

RESUMO

Little is known about the transcriptomic plasticity and adaptive mechanisms of circulating tumor cells (CTCs) during hematogeneous dissemination. Here we interrogate the transcriptome of 113 single CTCs from 4 different vascular sites, including hepatic vein (HV), peripheral artery (PA), peripheral vein (PV) and portal vein (PoV) using single-cell full-length RNA sequencing in hepatocellular carcinoma (HCC) patients. We reveal that the transcriptional dynamics of CTCs were associated with stress response, cell cycle and immune-evasion signaling during hematogeneous transportation. Besides, we identify chemokine CCL5 as an important mediator for CTC immune evasion. Mechanistically, overexpression of CCL5 in CTCs is transcriptionally regulated by p38-MAX signaling, which recruites regulatory T cells (Tregs) to facilitate immune escape and metastatic seeding of CTCs. Collectively, our results reveal a previously unappreciated spatial heterogeneity and an immune-escape mechanism of CTC, which may aid in designing new anti-metastasis therapeutic strategies in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Heterogeneidade Genética , Evasão da Resposta Imune , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Células Neoplásicas Circulantes/imunologia , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Quimiocina CCL5/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Metástase Neoplásica , Células Neoplásicas Circulantes/metabolismo , Prognóstico , RNA-Seq , Transcriptoma , Microambiente Tumoral
9.
J Agric Food Chem ; 65(3): 626-631, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28035826

RESUMO

9α-Hydroxy-4-androstene-3,17-dione (9-OHAD) is a valuable steroid pharmaceutical intermediate which can be produced by the conversion of soybean phytosterols in mycobacteria. However, the unsatisfactory productivity and conversion efficiency of engineered mycobacterial strains hinder their industrial applications. Here, a sigma factor D (sigD) was investigated due to its dramatic downregulation during the conversion of phytosterols to 9-OHAD. It was determined as a negative regulator in the metabolism of phytosterols, and the deletion of sigD in a 9-OHAD-producing strain significantly enhanced the titer of 9-OHAD by 18.9%. Furthermore, a high yielding strain was constructed by the combined modifications of sigD and choM2, a key gene in the phytosterol metabolism pathway. After the modifications, the productivity of 9-OHAD reached 0.071 g/L/h (10.27 g/L from 20 g/L phytosterol), which was 22.5% higher than the original productivity of 0.058 g/L/h (8.37 g/L from 20 g/L phytosterol) in the industrial resting cell biotransformation system.


Assuntos
Androstenodiona/análogos & derivados , Proteínas de Bactérias/metabolismo , Mycobacterium/metabolismo , Fitosteróis/metabolismo , Extratos Vegetais/metabolismo , Fator sigma/metabolismo , Androstenodiona/química , Androstenodiona/metabolismo , Proteínas de Bactérias/genética , Biotransformação , Mycobacterium/química , Mycobacterium/genética , Fitosteróis/química , Extratos Vegetais/química , Fator sigma/genética , Glycine max/metabolismo
10.
Zhonghua Nei Ke Za Zhi ; 45(2): 127-9, 2006 Feb.
Artigo em Zh | MEDLINE | ID: mdl-16624121

RESUMO

OBJECTIVE: To study the clinical manifestation and pathological features of histiocytic necrotizing lymphadenitis (Kikuchi's disease, KD). METHODS: 52 patients with KD were collected to analyze the clinical manifestation, pathological features of biopsy lymph nodes, diagnosis and treatment. RESULTS: 41 cases (79%) were female of the 52 patients. The main clinical features included persistent fever (100%), single (23%)/multi (77%)-lymphadenopathy (always in cervical region), pleomorphism erythra (35%), neutropenia (76%), elevated erythrocyte sedimentation rate (100%), insensitivity to antibiotics (100%) and sensitivity to small dosage glucocorticoid (81%). 26 cases (50%) had elevated aspartate aminotransferase and/or alanine aminotransferase, but only 7 cases (13%) had upper respiratory tract symptom like influenza. Pathological features included distinctive necrosis, loss of lymph node structure, infiltration with histiocytes and lymphocytes, absence of neutrophils. Immunohistochemical stainings showed CD(68) positive for histiocytes and CD(3), CD(45) RO positive for T lymphocytes. CONCLUSION: Diagnosis of KD relies on the pathological examination and immunohistochemical staining.


Assuntos
Linfadenite Histiocítica Necrosante/diagnóstico , Linfonodos/patologia , Adolescente , Adulto , Biópsia , Feminino , Linfadenite Histiocítica Necrosante/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Sci Rep ; 6: 21928, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26898409

RESUMO

The catabolism of sterols in mycobacteria is highly important due to its close relevance in the pathogenesis of pathogenic strains and the biotechnological applications of nonpathogenic strains for steroid synthesis. However, some key metabolic steps remain unknown. In this study, the hsd4A gene from Mycobacterium neoaurum ATCC 25795 was investigated. The encoded protein, Hsd4A, was characterized as a dual-function enzyme, with both 17ß-hydroxysteroid dehydrogenase and ß-hydroxyacyl-CoA dehydrogenase activities in vitro. Using a kshAs-null strain of M. neoaurum ATCC 25795 (NwIB-XII) as a model, Hsd4A was further confirmed to exert dual-function in sterol catabolism in vivo. The deletion of hsd4A in NwIB-XII resulted in the production of 23,24-bisnorcholenic steroids (HBCs), indicating that hsd4A plays a key role in sterol side-chain degradation. Therefore, two competing pathways, the AD and HBC pathways, were proposed for the side-chain degradation. The proposed HBC pathway has great value in illustrating the production mechanism of HBCs in sterol catabolism and in developing HBCs producing strains for industrial application via metabolic engineering. Through the combined modification of hsd4A and other genes, three HBCs producing strains were constructed that resulted in promising productivities of 0.127, 0.109 and 0.074 g/l/h, respectively.


Assuntos
Mycobacterium/metabolismo , Esteróis/metabolismo , 17-Hidroxiesteroide Desidrogenases/genética , 17-Hidroxiesteroide Desidrogenases/metabolismo , 3-Hidroxiacil-CoA Desidrogenases/genética , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Biotransformação , Colenos/metabolismo , Genes Bacterianos , Microbiologia Industrial , Engenharia Metabólica , Mycobacterium/genética , Esteroides/biossíntese
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(5): 792-5, 2005 May.
Artigo em Zh | MEDLINE | ID: mdl-16128092

RESUMO

A rapid and sensitive methed for the determination of trace cadmium in environment water samples based on flowinjection on-line preconcentration on two-microcolumn system-flame atomic absorption spectrometry has been developed. The cadmium in samples was sequentially retained on two microcolumns with cation exchange resin and was eluted directly in the nebulizer by 1.5 mol x L(-1) HCl solution. The characteristic concentration (preconcentration time 1 min) for cadmium was 0.931 microg x L(-1). The relative standard deviation at the 5 microg x L(-1) level was 2.69% and the corresponding detection limit (3sigma) was 0.808 microg x L(-1). The method has been successfully applied to the determination of cadmium in water reference material GBW08608 and other water samples.


Assuntos
Cádmio/análise , Espectrofotometria Atômica/métodos , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Análise de Injeção de Fluxo , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Espectrofotometria Atômica/instrumentação , Fatores de Tempo
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