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3.
Cancer Cell Int ; 21(1): 621, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34819088

RESUMEN

BACKGROUND: The aim of this study was to construct a model based on the prognostic features associated with epithelial-mesenchymal transition (EMT) to explore the various mechanisms and therapeutic strategies available for the treatment of metastasis and invasion by hepatocellular carcinoma (HCC) cells. METHODS: EMT-associated genes were identified, and their molecular subtypes were determined by consistent clustering analysis. The differentially expressed genes (DEGs) among the molecular subtypes were ascertained using the limma package and they were subjected to functional enrichment analysis. The immune cell scores of the molecular subtypes were evaluated using ESTIMATE, MCPcounter, and GSCA packages of R. A multi-gene prognostic model was constructed using lasso regression, and the immunotherapeutic effects of the model were analyzed using the Imvigor210 cohort. In addition, immunohistochemical analysis was performed on a cohort of HCC tissue to validate gene expression. RESULTS: Based on the 59 EMT-associated genes identified, the 365-liver hepatocellular carcinoma (LIHC) samples were divided into two subtypes, C1 and C2. The C1 subtype mostly showed poor prognosis, had higher immune scores compared to the C2 subtype, and showed greater correlation with pathways of tumor progression. A four-gene signature construct was fabricated based on the 1130 DEGs among the subtypes. The construct was highly robust and showed stable predictive efficacy when validated using datasets from different platforms (HCCDB18 and GSE14520). Additionally, compared to currently existing models, our model demonstrated better performance. The results of the immunotherapy cohort showed that patients in the low-risk group have a better immune response, leading to a better patient's prognosis. Immunohistochemical analysis revealed that the expression levels of the FTCD, PON1, and TMEM45A were significantly over-expressed in 41 normal samples compared to HCC samples, while that of the G6PD was significantly over-expressed in cancerous tissues. CONCLUSIONS: The four-gene signature construct fabricated based on the EMT-associated genes provides valuable information to further study the pathogenesis and clinical management of HCC.

4.
Micromachines (Basel) ; 12(3)2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33809783

RESUMEN

Rapid tooling technology (RTT) provides an alternative approach to quickly provide wax injection molds for the required products since it can reduce the time to market compared with conventional machining approaches. Removing conformal cooling channels (CCCs) is the key technology for manufacturing injection mold fabricated by rapid tooling technology. In this study, three different kinds of materials were used to fabricate CCCs embedded in the injection mold. This work explores a technology for rapid development of injection mold with high cooling performance. It was found that wax is the most suitable material for making CCCs. An innovative method for fabricating a large intermediary mold with both high load and supporting capacities for manufacturing a large rapid tooling using polyurethane foam was demonstrated. A trend equation for predicting the usage amount of polyurethane foam was proposed. The production cost savings of about 50% can be obtained. An optimum conformal cooling channel design obtained by simulation is proposed. Three injection molds with different cooling channels for injection molding were fabricated by RTT. Reductions in the cooling time by about 89% was obtained. The variation of the results between the experiment and the simulation was investigated and analyzed.

5.
Cell Death Dis ; 12(2): 162, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33558466

RESUMEN

Hepatocellular carcinoma (HCC) is a common high-mortality cancer, mainly due to diagnostic difficulties during its early clinical stages. In this study, we aimed to identify genes that are important for HCC diagnosis and treatment, and we investigated the underlying mechanism of prognostic differences. Differentially expressed genes (DEGs) were identified by using the limma package, and receiver operating characteristic curve analysis was performed to identify diagnostic markers for HCC. Bioinformatics and clinical specimens were used to assess epithelial cell transforming 2 (ECT2) in terms of expression, prognostic value, pathways, and immune correlations. In vitro experiments were used to investigate the underlying mechanism and function of ECT2, and the results were confirmed through in vivo experiments. The integrated analysis revealed 53 upregulated DEGs, and one candidate biomarker for diagnosis (ECT2) was detected. High expression of ECT2 was found to be an independent prognostic risk factor for HCC. ECT2 expression showed a strong correlation with tumor-associated macrophages. We found that ECT2 overexpression increased the migration and proliferation of HCC cells. It also promoted the expression of PLK1, which subsequently interacted with PTEN and interfered with its nuclear translocation, ultimately enhancing aerobic glycolysis and promoting M2 macrophage polarization. M2 macrophages suppress the functions of NK cells and T cells, and this was confirmed in the in vivo experiments. Overall, ECT2 may promote the polarization of M2 macrophages by enhancing aerobic glycolysis and suppressing the functions of immune cells. ECT2 could serve as a candidate diagnostic and prognostic biomarker for HCC.


Asunto(s)
Carcinoma Hepatocelular/enzimología , Proteínas de Ciclo Celular/metabolismo , Plasticidad de la Célula , Neoplasias Hepáticas/enzimología , Fosfohidrolasa PTEN/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Macrófagos Asociados a Tumores/enzimología , Apoptosis , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Proteínas de Ciclo Celular/genética , Movimiento Celular , Proliferación Celular , Bases de Datos Genéticas , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Glucólisis , Células Hep G2 , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Invasividad Neoplásica , Fosfohidrolasa PTEN/genética , Fenotipo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Transducción de Señal , Microambiente Tumoral , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/patología , Regulación hacia Arriba , Quinasa Tipo Polo 1
6.
Molecules ; 20(7): 12787-803, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26184152

RESUMEN

Rhododendron formosanum is an endemic species distributed in the central mountains of Taiwan. In this study, the biological activities of major procyanidins isolated from the leaf extract of R. formosanum were investigated. Four compounds, including two procyanidin dimers, procyanidin A1 (1) and B3 (2), and two procyanidin trimmers, procyanidin C4 (4) and cinnamtannin D1 (5), were isolated and identified on the basis of spectroscopic data. The structure of a new procyanidin dimer, rhodonidin A (3), was elucidated by 2D-NMR, CD spectrum and MS. The procyanidin trimmers and rhodonidin A are reported for the first time in Ericaceae. The biological activities of these procyanidins were evaluated using anti-bacterial and anti-oxidative assays. Only the new compound 3 demonstrated strong anti-bacterial activity against Staphylococcus aureus at an MIC value of 4 µg/mL. All compounds showed pronounced antioxidant activities and the activities are enhanced as the amount of OH groups in procyanidins increased. In conclusion, the pleiotropic effects of procyanidins isolated from the leaves of R. formosanum can be a source of promising compounds for the development of future pharmacological applications.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Hojas de la Planta/química , Proantocianidinas/química , Rhododendron/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxidación-Reducción , Picratos/antagonistas & inhibidores , Picratos/química , Extractos Vegetales/química , Proantocianidinas/aislamiento & purificación , Proantocianidinas/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Relación Estructura-Actividad , Taiwán
7.
J Chem Ecol ; 40(1): 90-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24390624

RESUMEN

Alstonia scholaris is a tropical evergreen tree native to South and Southeast Asia. Alstonia forests frequently lack understory species. However, potential mechanisms-particularly the allelochemicals involved-remain unclear. In the present study, we identified allelochemicals of A. scholaris, and clarified the role of allelopathic substances from A. scholaris in interactions with neighboring plants. We showed that the leaves, litter, and soil from A. scholaris inhibited growth of Bidens pilosa-a weed found growing abundantly near A. scholaris forests. The allelochemicals were identified as pentacyclic triterpenoids, including betulinic acid, oleanolic acid, and ursolic acid by using (1)H and (13)C-NMR spectroscopy. The half-maximal inhibitory concentration (IC50) for radicle growth of B. pilosa and Lactuca sativa ranged from 78.8 µM to 735.2 µM, and ursolic acid inhibited seed germination of B. pilosa. The triterpenoid concentrations in the leaves, litter, and soil were quantified with liquid chromatography-electrospray ionization/tandem mass spectrometry. Ursolic acid was present in forest soil at a concentration of 3,095 µg/g, i.e., exceeding the IC50. In the field, ursolic acid accumulated abundantly in the soil in A. scholaris forests, and suppressed weed growth during summer and winter. Our results indicate that A. scholaris pentacyclic triterpenoids influence the growth of neighboring weeds by inhibiting seed germination, radicle growth, and functioning of photosystem II.


Asunto(s)
Alelopatía , Alstonia/metabolismo , Feromonas/química , Feromonas/farmacología , Triterpenos/química , Triterpenos/farmacología , Bidens/efectos de los fármacos , Bidens/crecimiento & desarrollo , Bidens/metabolismo , Germinación/efectos de los fármacos , Feromonas/análisis , Feromonas/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Malezas/efectos de los fármacos , Malezas/crecimiento & desarrollo , Malezas/metabolismo , Suelo/química , Triterpenos/análisis , Triterpenos/metabolismo , Ácido Ursólico
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