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1.
Molecules ; 28(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687050

RESUMO

Five new lipids, tricholixins A-E (1-5), and two known terpenoids, brasilane A (6) and harzianone A (7), were discovered from a deep-sea strain (R22) of the fungus Trichoderma lixii isolated from the cold seep sediments of the South China Sea. Their structures and relative configurations were identified by meticulous analysis of MS and IR as well as NMR data. The absolute configuration of 5 was ascertained by dimolybdenum-induced ECD data in particular. Compounds 1 and 2 represent the only two new butenolides from marine-derived Trichoderma, and they further add to the structural diversity of these molecules. Although 6 has been reported from a basidiomycete previously, it is the first brasilane aminoglycoside of Trichoderma origin. During the assay against wheat-pathogenic fungi, both 1 and 2 inhibited Fusarium graminearum with an MIC value of 25.0 µg/mL, and 6 suppressed Gaeumannomyces graminis with an MIC value of 12.5 µg/mL. Moreover, the three isolates also showed low toxicity to the brine shrimp Artemia salina.


Assuntos
Hypocreales , Trichoderma , Animais , Terpenos/farmacologia , Artemia , Lipídeos
2.
Nat Prod Res ; : 1-6, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37194666

RESUMO

Two new compounds, cladospolides I (1) and J (2), together with two new naturally occurring ones, methyl 11-hydroxy-4-oxododecanoate (3) and 11-hydroxy-4-oxododecanoic acid (4), were isolated from the culture extract of the cold-seep sediment-derived fungus Cladosporium cladosporioides 8-1. Their structures and configurations were established by analysis of 1D/2D NMR, MS, ECD, and specific optical rotation data. Compound 3 was possibly formed by methyl esterification of 4 during the purification process due to the utilization of methanol. All compounds were evaluated for inhibition of four marine phytoplankton species and five marine-derived bacteria.

5.
Chin J Cancer ; 35(1): 80, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27527497

RESUMO

BACKGROUND: Small hepatocellular carcinoma (sHCC) is a unique variant of HCC that is characterized by small tumor size (maximum tumor diameter ≤3 cm) and favorable long-term outcomes. The present study aimed to define clinicopathologic factors that predict survival in patients with sHCC. METHODS: The study population consisted of 335 patients who underwent hepatectomy for solitary sHCC between December 1998 and 2010. Prognostic factors were evaluated using Kaplan-Meier curves and Cox proportional hazard models. RESULTS: The 5-year overall survival (OS) and recurrence-free survival (RFS) rates were 77.7% and 59.9%, respectively. Kaplan-Meier curves showed that tumor size and vascular invasion had prognostic significance within this relatively selected cohort (P < 0.05). Multivariate analysis confirmed that increased tumor size and vascular invasion were independent prognostic factors for short OS (hazard ratio [HR] = 2.367, 95% confidence interval [CI] 1.406-3.985; HR = 2.954, 95% CI 1.781-4.900) and RFS (HR = 1.779, 95% CI 1.259-2.514; HR = 1.699, 95% CI 1.165-2.477) in sHCC patients (P < 0.05). Importantly, a proposed prognostic scoring model was derived according to the two variables; tumor size and extent of vascular invasion were significantly associated with OS and RFS in patients with sHCC (P < 0.001). CONCLUSIONS: Tumor size and vascular invasion are feasible and useful prognostic factors for sHCC. The proposed prognostic model, based on tumor size and vascular invasion, is informative in predicting survival in sHCC patients undergoing hepatectomy.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma de Células Pequenas/mortalidade , Hepatectomia/mortalidade , Neoplasias Hepáticas/mortalidade , Recidiva Local de Neoplasia/mortalidade , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Pequenas/cirurgia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
6.
Carcinogenesis ; 37(6): 557-566, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27207647

RESUMO

Trimethylation of lysine 27 on histone H3 (H3K27ME3) is a transcription-suppressive histone mark mediated by enhancer of zeste homolog 2 (EZH2). We have previously suggested that EZH2-mediated H3K27ME3 plays a critical oncogenic role in human hepatocellular carcinoma (HCC) aggressiveness. However, the direct downstream targets of EZH2-H3K27ME3 and the molecular mechanisms by which regulates HCC pathogenesis remain unclear. In this study, we used chromatin immunoprecipitation together with high-throughput sequencing (ChIP-seq) and gene expression profiling by microarray analysis to assess genome-wide chromatin occupancy of H3K27ME3 in HCC cells. We identified that claudin14 (CLDN14) is a potentially direct target for EZH2-mediated H3K27ME3 in HCC. In a large cohort of clinical HCC tissues, we found that low expression of CLDN14 was significantly associated with advanced tumor stage and determined to be an independent predictor of shortened survival of HCC patients. Next, functional experiment demonstrated that depletion of CLDN14 substantially restored EZH2-silenced HCC cells motility and invasive capacities and supported cell epithelial-mesenchymal transition (EMT). Furthermore, downregulation of CLDN14 dramatically re-enhanced the wnt/ß-catenin signaling activity in EZH2-silenced HCC cells by increasing the levels of active ß-catenin and promoting the nuclear localization of ß-catenin. These results, collectively, uncover that CLDN14 is a novel direct target of EZH2-mediated H3K27ME3, and provide an explanation for the aggressive nature of HCC with downregulation of CLDN14 and the underling mechanism that links the tumor suppressor CLDN14 to the wnt/ß-catenin signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Claudinas/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Hepáticas/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Claudinas/metabolismo , Intervalo Livre de Doença , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Metilação , Prognóstico , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
7.
BMC Cancer ; 14: 583, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-25109220

RESUMO

BACKGROUND: Hemostatic alterations occur during the development of cancer. Plasma D-dimer is a hypercoagulability and fibrinolytic system marker that is increased in patients with various solid tumours. The aim of this study was to evaluate the hemostatic status of nasopharyngeal carcinoma (NPC) patients by assessing plasma D-dimer levels to investigate its value as a prognostic marker. METHODS: We retrospectively analysed 717 patients with nasopharyngeal carcinoma, and we applied Cox regression and log-rank tests to assess the association of D-dimer levels with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS). D-dimer levels were measured using a quantitative D-dimer latex agglutination assay. RESULTS: Using the 3rd quartile values (0.8 µg/L) as the optimal cut-offs, we found that patients with high D-dimer levels have a shorter 3-year DFS, (79%, 95%CI (73.1-84.9)) vs. (69%, 95%CI (59.2-78.8)), DMFS (87%, 95%CI (83.1-90.9)) vs. (77%, 95%CI (69.2-84.8)), and overall survival (82%, 95%CI (76.1-87.9)) vs. (76%, 95%CI (66.2-85.8)). Multivariate analysis revealed that pre-treatment D-dimer levels and EBV DNA were significant independent factors for DFS, DMFS, and OS in NPC patients. Subgroup analyses indicated that the plasma D-dimer levels could effectively stratify patient prognosis for early cancer, advanced stage cancer, and patients with EBV DNA ≥4000 copies/ml. CONCLUSIONS: High D-dimer levels were associated with poor disease-free survival, distant metastasis-free survival, overall survival, and increased risk of mortality in NPC patients. Prospective trials are required to assess the prognostic value of D-dimer levels.


Assuntos
Quimiorradioterapia , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia , Adulto , Idoso , Carcinoma , DNA Viral/sangue , Feminino , Herpesvirus Humano 4/genética , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/mortalidade , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
8.
Oncotarget ; 5(16): 6716-33, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25071013

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is a highly vascularized tumor with poor clinical outcome. Our previous work has shown that eukaryotic initiation factor 5A2 (EIF5A2) over-expression enhances HCC cell metastasis. In this study, EIF5A2 was identified to be an independent risk factor for poor disease-specific survival among HCC patients. Both in vitro and in vivo assays indicated that ablation of endogenous EIF5A2 inhibited tumor angiogenesis by reducing matrix metalloproteinase 2 (MMP-2) expression. Given that MMP-2 degrades collagen IV, a main component of the vascular basement membrane (BM), we subsequently investigated the effect of EIF5A2 on tumor vasculature remodeling using complementary approaches, including fluorescent immunostaining, transmission electron microscopy, tumor perfusion assays and tumor hypoxia assays. Taken together, our results indicate that EIF5A2 silencing increases tumor vessel wall continuity, increases blood perfusion and improves tumor oxygenation. Additionally, we found that ablation of EIF5A2 enhanced the chemosensitivity of HCC cells to 5-Fluorouracil (5-FU). Finally, we demonstrated that EIF5A2 might exert these functions by enhancing MMP-2 activity via activation of p38 MAPK and JNK/c-Jun pathways. CONCLUSION: This study highlights an important role of EIF5A2 in HCC tumor vessel remodeling and indicates that EIF5A2 represents a potential therapeutic target in the treatment of HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Metaloproteinase 2 da Matriz/biossíntese , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/terapia , Fatores de Iniciação de Peptídeos/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A
9.
Cancer Lett ; 353(1): 104-14, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25045845

RESUMO

Paclitaxel is a main ingredient in the combination chemotherapy treatment of advanced human cervical squamous cell carcinomas. We investigated the roles and underlying molecular mechanisms of PinX1 in cervical squamous cell carcinomas (CSCC) cells response to paclitaxel and its clinical significances. The expression dynamics of PinX1 was first examined by immunohistochemistry in 122 advanced CSCC patients treated with cisplatin/paclitaxel chemotherapy. The expression of PinX1 was significantly associated with the effects of cisplatin/paclitaxel chemotherapy in advanced CSCCs (P<0.05). High expression of PinX1 correlated with CSCC's response to cisplatin/paclitaxel chemotherapy, and was an independent predictor of shortened survival (P<0.05). A series of in vivo and in vitro assays were performed to elucidate the function of PinX1 on CSCC cells chemosensitivity to paclitaxel and underlying mechanisms. In CSCC cells, the levels of PinX1 were only associated with the cytotoxicity and sensitivity of paclitaxel, in which knockdown of PinX1 dramatically enhanced paclitaxel cytotoxicity, whereas the reestablishment of PinX1 levels substantially reduced the paclitaxel-induced killing effect. In addition, we identified that the ability of PinX1 to stabilize the tension between sister kinetochores and maintain the spindle assembly checkpoint was the main reason CSCC cells undergo apoptosis when treated with paclitaxel, and further studies demonstrated that shortened distance between sisters kinetochores by nocodazole confers upon PinX1-replenished cells a sensitivity to the death inducing paclitaxel effects. Furthermore, our study of CSCC cells xenografts in nude mice confirmed the role of PinX1 in paclitaxel sensitivity in vivo. Our data reveal that PinX1 could be used as a novel predictor for CSCC patient response to paclitaxel, and the role of PinX1-mediated paclitaxel sensitivity might represent a new direction for the development of a new generation of microtubule drugs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Fuso Acromático/efeitos dos fármacos , Telômero/efeitos dos fármacos , Proteínas Supressoras de Tumor/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Proteínas de Ciclo Celular , Cisplatino/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Feminino , Células HeLa , Humanos , Cinetocoros/efeitos dos fármacos , Cinetocoros/metabolismo , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Interferência de RNA , Fuso Acromático/metabolismo , Análise de Sobrevida , Telomerase/metabolismo , Telômero/metabolismo , Fatores de Tempo , Transfecção , Resultado do Tratamento , Moduladores de Tubulina/administração & dosagem , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Oncol Lett ; 7(6): 2047-2052, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24932287

RESUMO

Pien Tze Huang (PZH) is a well-known Chinese medicine that has been used as a therapeutic drug in the treatment of a number of diseases, such as hepatocellular carcinoma and colon cancer. However, few studies have analyzed the effects of PZH on ovarian cancer cell proliferation. In the present study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assays, cell cycle and apoptosis rate analyses and western blotting were conducted to investigate the effects of PZH on the proliferation rate of ovarian cancer cells and its potential molecular pathway. The results showed that PZH inhibits the proliferation of the human ovarian cancer OVCAR-3 cell line by blocking the progression of the cell cycle from the G1 to S phase, however, PZH did not induce OVCAR-3 cell apoptosis. Increased PZH concentration may downregulate the expression of AKT, phosphorylated (p)-AKT, mammalian target of rapamycin (mTOR) and p-mTOR proteins in the OVCAR-3 cell line. In addition, it was observed that PZH may suppress the protein expression of cyclin-dependent kinase (CDK)4 and CDK6. Overall, the results of the present study indicated that PZH may inhibit ovarian cancer cell proliferation by modulating the activity of the AKT-mTOR pathway.

11.
ACS Nano ; 3(10): 3301-7, 2009 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-19719156

RESUMO

Anodization of Al is used to produce optically smooth porous alumina (Al(2)O(3)) films with pores approximately 60 nm in diameter and approximately 6 mum deep. The capture protein, protein A, is adsorbed to the pore walls by noncovalent, electrostatic interactions, and thin film interference spectroscopy is used to detect binding of immunoglobulin (IgG). The porous alumina films are stable against corrosion and dissolution in aqueous media at pH 7, allowing quantitative monitoring of steady-state and time-resolved biomolecular binding. The bare porous Al(2)O(3) surface displays a significantly greater affinity for protein A than for IgG. The known species specificity of protein A binding to IgG is confirmed; the protein-A-modified sensor responds to IgG derived from rabbit, but not chicken (IgG/IgY). A "cascaded", or multiprobe sensing approach, is demonstrated, in which a specific target, sheep IgG, is administered to a sample modified with a protein A/rabbit anti-sheep IgG assembly. Binding measurements are confirmed by fluorescence microscopy using fluorescein-labeled IgG.


Assuntos
Óxido de Alumínio/química , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Animais , Imunoglobulina G/análise , Imunoglobulina G/metabolismo , Interferometria , Cinética , Porosidade , Ligação Proteica , Coelhos , Coloração e Rotulagem , Propriedades de Superfície
12.
Nanotechnology ; 19(31): 315709, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21828801

RESUMO

Gas adsorption and capillary condensation of organic vapors are studied by optical interferometry, using anodized nanoporous alumina films with controlled geometry (cylindrical pores with diameters in the range of 10-60 nm). The optical response of the film is optimized with respect to the geometric parameters of the pores, for potential performance as a gas sensor device. The average thickness of the adsorbed film at low relative pressures is not affected by the pore size. Capillary evaporation of the liquid from the nanopores occurs at the liquid-vapor equilibrium described by the classical Kelvin equation with a hemispherical meniscus. Due to the almost complete wetting, we can quantitatively describe the condensation for isopropanol using the Cohan model with a cylindrical meniscus in the Kelvin equation. This model describes the observed hysteresis and allows us to use the adsorption branch of the isotherm to calculate the pore size distribution of the sample in good agreement with independent structural measurements. The condensation for toluene lacks reproducibility due to incomplete surface wetting. This exemplifies the relevant role of the fluid-solid (van der Waals) interactions in the hysteretic behavior of capillary condensation.

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