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1.
Int J Mol Sci ; 24(7)2023 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37047623

RESUMO

Colorectal cancer is one of the most prevalent and lethal malignancies, affecting approximately 900,000 individuals each year worldwide. Patients with colorectal cancer are found with elevated serum interleukin-6 (IL-6), which is associated with advanced tumor grades and is related to their poor survival outcomes. Although IL-6 is recognized as a potent inducer of colorectal cancer progression, the detail mechanisms underlying IL-6-induced colorectal cancer epithelial-mesenchymal transition (EMT), one of the major process of tumor metastasis, remain unclear. In the present study, we investigated the regulatory role of IL-6 signaling in colorectal cancer EMT using HCT116 human colorectal cancer cells. We noted that the expression of epithelial marker E-cadherin was reduced in HCT116 cells exposed to IL-6, along with the increase in a set of mesenchymal cell markers including vimentin and α-smooth muscle actin (α-SMA), as well as EMT transcription regulators-twist, snail and slug. The changes of EMT phenotype were related to the activation of Src, FAK, ERK1/2, p38 mitogen-activated protein kinase (p38MAPK), as well as transcription factors STAT3, κB and C/EBPß. IL-6 treatment has promoted the recruitment of STAT3, κB and C/EBPß toward the Twist promoter region. Furthermore, the Src-FAK signaling blockade resulted in the decline of IL-6 induced activation of ERK1/2, p38MAPK, κB, C/EBPß and STAT3, as well as the decreasing mesenchymal state of HCT116 cells. These results suggested that IL-6 activates the Src-FAK-ERK/p38MAPK signaling cascade to cause the EMT of colorectal cancer cells. Pharmacological approaches targeting Src-FAK signaling may provide potential therapeutic strategies for rescuing colorectal cancer progression.


Assuntos
Neoplasias Colorretais , Interleucina-6 , Humanos , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal/genética , Interleucina-6/metabolismo , Transdução de Sinais , Genes src
2.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903603

RESUMO

Hepatocellular carcinoma is the third most common cause of cancer-related death according to the International Agency for Research on Cancer. Dihydroartemisinin (DHA), an antimalarial drug, has been reported to exhibit anticancer activity but with a short half-life. We synthesized a series of bile acid-dihydroartemisinin hybrids to improve its stability and anticancer activity and demonstrated that an ursodeoxycholic-DHA (UDC-DHA) hybrid was 10-fold more potent than DHA against HepG2 hepatocellular carcinoma cells. The objectives of this study were to evaluate the anticancer activity and investigate the molecular mechanisms of UDCMe-Z-DHA, a hybrid of ursodeoxycholic acid methyl ester and DHA via a triazole linkage. We found that UDCMe-Z-DHA was even more potent than UDC-DHA in HepG2 cells with IC50 of 1 µM. Time course experiments and stability in medium determined by cell viability assay as well as HPLC-MS/MS analysis revealed that UDCMe-Z-DHA was more stable than DHA, which in part accounted for the increased anticancer activity. Mechanistic studies revealed that UDCMe-Z-DHA caused G0/G1 arrest and induced reactive oxygen species (ROS), mitochondrial membrane potential loss and autophagy, which may in turn lead to apoptosis. Compared to DHA, UDCMe-Z-DHA displayed much lower cytotoxicity toward normal cells. Thus, UDCMe-Z-DHA may be a potential drug candidate for hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Ácido Ursodesoxicólico , Neoplasias Hepáticas/patologia , Espectrometria de Massas em Tandem , Apoptose , Artemeter , Linhagem Celular Tumoral
3.
Sensors (Basel) ; 22(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36501794

RESUMO

Imaging tasks today are being increasingly shifted toward deep learning-based solutions. Biomedical imaging problems are no exception toward this tendency. It is appealing to consider deep learning as an alternative to such a complex imaging task. Although research of deep learning-based solutions continues to thrive, challenges still remain that limits the availability of these solutions in clinical practice. Diffuse optical tomography is a particularly challenging field since the problem is both ill-posed and ill-conditioned. To get a reconstructed image, various regularization-based models and procedures have been developed in the last three decades. In this study, a sensor-to-image based neural network for diffuse optical imaging has been developed as an alternative to the existing Tikhonov regularization (TR) method. It also provides a different structure compared to previous neural network approaches. We focus on realizing a complete image reconstruction function approximation (from sensor to image) by combining multiple deep learning architectures known in imaging fields that gives more capability to learn than the fully connected neural networks (FCNN) and/or convolutional neural networks (CNN) architectures. We use the idea of transformation from sensor- to image-domain similarly with AUTOMAP, and use the concept of an encoder, which is to learn a compressed representation of the inputs. Further, a U-net with skip connections to extract features and obtain the contrast image, is proposed and implemented. We designed a branching-like structure of the network that fully supports the ring-scanning measurement system, which means it can deal with various types of experimental data. The output images are obtained by multiplying the contrast images with the background coefficients. Our network is capable of producing attainable performance in both simulation and experiment cases, and is proven to be reliable to reconstruct non-synthesized data. Its apparent superior performance was compared with the results of the TR method and FCNN models. The proposed and implemented model is feasible to localize the inclusions with various conditions. The strategy created in this paper can be a promising alternative solution for clinical breast tumor imaging applications.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Óptica , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação
4.
J Cell Mol Med ; 24(2): 1822-1836, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31821701

RESUMO

There is increasing evidence that statins, which are widely used in lowering serum cholesterol and the incidence of cardiovascular diseases, also exhibits anti-tumour properties. The underlying mechanisms by which statins-induced cancer cell death, however, remain incompletely understood. In this study, we explored the anti-tumour mechanisms of a lipophilic statin, lovastatin, in MCF-7 breast cancer cells. Lovastatin inhibited cell proliferation and induced cell apoptosis. Lovastatin caused p21 elevation while reduced cyclin D1 and survivin levels. Lovastatin also increased p53 phosphorylation, acetylation and its reporter activities. Results from chromatin immunoprecipitation analysis showed that p53 binding to the survivin promoter region was increased, while Sp1 binding to the region was decreased, in MCF-7 cells after lovastatin exposure. These actions were associated with liver kinase B1 (LKB1), AMP-activated protein kinase (AMPK) and p38 mitogen-activated protein kinase (p38MAPK) activation. Lovastatin's enhancing effects on p53 activation, p21 elevation and survivin reduction were significantly reduced in the presence of p38MAPK signalling inhibitor. Furthermore, LKB1-AMPK signalling blockade abrogated lovastatin-induced p38MAPK and p53 phosphorylation. Together these results suggest that lovastatin may activate LKB1-AMPK-p38MAPK-p53-survivin cascade to cause MCF-7 cell death. The present study establishes, at least in part, the signalling cascade by which lovastatin induces breast cancer cell death.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Lovastatina/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Survivina/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Células MCF-7 , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
5.
Biochim Biophys Acta ; 1830(8): 4053-64, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23583370

RESUMO

BACKGROUND: Statins, the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors with cholesterol-lowering properties, were recently shown to exhibit anti-cancer effects. However, the molecular mechanism underlying statin-induced cancer cell death remains to be elucidated. Elevated level of survivin is often found over-expressed in human cancers and has been implicated in the progression of tumorigenesis. Given its central role in cell division and action as an apoptosis suppressor, survivin represents a potential molecular target in cancer management. METHODS: In this study, we explored the underlying mechanisms in simvastatin-induced HCT116 colorectal cancer cell apoptosis. RESULTS: Simvastatin decreased cell viability and induced cell apoptosis in HCT116 cells. These results are associated with the modulation of p21(cip/Waf1) and survivin. Survivin knockdown using survivin siRNAs also decreased cell viability and induced cell apoptosis. Simvastatin's actions on p21(cip/Waf1), survivin and apoptosis were reduced in p53 null HCT116 cells. Simvastatin caused an increase in p53 phosphorylation and acetylation. In addition, simvastatin activated p38 mitogen-activated protein kinase (p38MAPK), whereas an inhibitor of p38MAPK signaling abrogated simvastatin's effects of increasing p53 and p21(cip/Waf1) promoter luciferase activity. Cell viability and survivin promoter luciferase activity in the presence of simvastatin were also restored by p38MAPK inhibitor. Furthermore, Sp1 binding to the survivin promoter region decreased while p53 and p63 binding to the promoter region increased after simvastatin exposure. CONCLUSIONS: Simvastatin activates the p38MAPK-p53-survivin cascade to cause HCT116 colorectal cancer cell apoptosis. GENERAL SIGNIFICANCE: This study delineates, in part, the underlying mechanisms of simvastatin in decreasing survivin and subsequent colorectal cancer cell apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Proteínas Inibidoras de Apoptose/fisiologia , Transdução de Sinais , Sinvastatina/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Acetilação , Sobrevivência Celular/efeitos dos fármacos , Células HCT116 , Humanos , Proteínas Inibidoras de Apoptose/genética , Regiões Promotoras Genéticas , Survivina , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Angiogenesis ; 17(2): 407-18, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24048742

RESUMO

Formation of lymphatic capillaries by lymphatic endothelial cells (LECs) occurs both in normal tissues as well as in pathological processes including tumor metastasis. Interleukin-6 (IL-6), a potent pro-inflammatory cytokine, has been shown to be highly elevated in various cancers. IL-6 has also been shown to increase tumor lymphangiogenesis through vascular endothelial growth factor-C (VEGF-C) induction in tumor cells. Although lymphangiogenesis is associated with lymph node metastasis and also resistance to conventional therapy in various cancers, the precise mechanisms of lymphangiogenesis in LECs remain unclear. This study aimed to investigate the signaling cascade involved in IL-6-induced VEGF-C expression in murine LECs (SV-LEC). The VEGF-C mRNA and protein levels were increased in SV-LECs exposed to IL-6. IL-6 time-dependently induced Src phosphorylation and downstream phosphorylation of ERK1/2 and p38MAPK. In contrast, PP2, an inhibitor of Src signaling, abrogated IL-6's effects on ERK1/2 and p38MAPK phosphorylation. IL-6 exposure also led to increase in VEGF-C promoter-luciferase activity as well as C/EBPß- and κB-luciferase activities. VEGF-C promoter-, C/EBPß- and κB-luciferase activities were all suppressed by Src, ERK1/2 or p38MAPK signaling blockades despite presence of IL-6. Finally, C/EBPß and p65 binding to the VEGF-C promoter region were increased after IL-6 exposure in SV-LECs. Taken together, we report a Src-mediated ERK1/2 and p38MAPK activation resulting in C/EBPß and p65 binding to the promoter region of VEGF-C, leading to VEGF-C expression in IL-6-exposed SV-LECs.


Assuntos
Células Endoteliais/metabolismo , Interleucina-6/farmacologia , Fator C de Crescimento do Endotélio Vascular/metabolismo , Quinases da Família src/metabolismo , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Biochim Biophys Acta ; 1820(2): 104-15, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22155142

RESUMO

BACKGROUND: Elevated levels of survivin and histone deacetylases (HDACs) are often found over-expressed in human cancers, including colorectal cancer, and have been implicated in tumorigenesis. HDAC inhibition induces growth arrest and cell death in various transformed cell; however, the mechanisms by which this reduces cell viability in colorectal cancer cells remain unexplained. METHODS: We explored the actions of two HDAC inhibitors, trichostatin A (TSA) and sirtinol, in HT29 colon cancer cells. RESULTS: TSA and sirtinol induced apoptosis and inhibited cell proliferation in HT29 cells. These results are associated with the modulation of survivin. Survivin promoter luciferase activity and Sp1, a transcription factor that contributes to survivin expression, were suppressed in cells exposed to TSA or sirtinol. TSA and sirtinol also activated p38 mitogen-activated protein kinase (p38MAPK) and AMP-activated protein kinase (AMPK). Inhibitors of p38MAPK or AMPK signaling abrogated TSA and sirtinol's effects of decreasing cell viability. Survivin promoter luciferase activity in the presence of TSA or sirtinol was restored by AMPK dominant negative mutant or p38MAPK inhibitor. Furthermore, Sp1 binding to the survivin promoter region decreased while p63 binding to the promoter region increased after TSA or sirtinol exposure. CONCLUSIONS: We report a p38MAPK- and AMPK-mediated downregulation of survivin, and its functional correlation with decreased colon cancer cell viability in the presence of HDAC inhibitor. p63 and Sp1 may also contribute to TSA and sirtinol actions. GENERAL SIGNIFICANCE: This study delineates, in part, the underlying mechanisms of TSA and sirtinol in decreasing survivin expression and subsequent colon cancer cell viability.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Benzamidas/farmacologia , Neoplasias do Colo/enzimologia , Ácidos Hidroxâmicos/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Naftóis/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Proteínas Inibidoras de Apoptose/genética , Luciferases/metabolismo , Plicamicina/análogos & derivados , Plicamicina/farmacologia , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Fator de Transcrição Sp1/metabolismo , Survivina , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
8.
BMC Public Health ; 13: 421, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23635081

RESUMO

BACKGROUND: There is substantial overlap between deliberate self-harm (DSH) and intention to suicide (ITS), although the psychopathologies and motivations behind these behaviors are distinctly different. The purpose of this study was to investigate (i) the pathway relationship among parental bonding, personality characteristics, and alexithymic traits, and (ii) the association of these features with ITS and DSH using structural equation modeling to determine the risks and protective factors for these behaviors. METHODS: Sixty-nine first-time DSH and 36 first-time ITS patients without medical or psychiatric illnesses, and 66 controls were recruited. The Parental Bonding Inventory (PBI), Eysenck Personality Questionnaire (EPQ), 20-item Toronto Alexithymia Scale (TAS-20), and the Chinese Health Questionnaire (CHQ) were filled out by the participants. RESULTS: Our structural equation models showed that parental bonding had the greatest influence on the development of DSH behavior in patients. On the other hand, participants who were younger, less extraverted, with a greater extent of the alexithymic trait of difficulty identifying feeling (DIF), and a worse mental health condition, were more likely to develop ITS behavior. Males were more likely than females to develop the alexithymic trait of DIF. CONCLUSIONS: Although there are many covariates that affect both ITS and DSH behaviors, these covariates may have different functions in the development of these behaviors, thus revealing the psychopathological difference between DSH and ITS. Policymakers should consider these differences and build intervention and prevention programs for gender- and age-specific high-risk groups to target the differences, with a focus on family counseling to treat DSH and a focus on attempting to increase emotional awareness to treat ITS.


Assuntos
Apego ao Objeto , Relações Pais-Filho , Comportamento Autodestrutivo/psicologia , Tentativa de Suicídio/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Manual Diagnóstico e Estatístico de Transtornos Mentais , Extroversão Psicológica , Saúde da Família , Feminino , Humanos , Entrevista Psicológica , Masculino , Pessoa de Meia-Idade , Comportamento Autodestrutivo/classificação , Comportamento Autodestrutivo/diagnóstico , Tentativa de Suicídio/classificação , Inquéritos e Questionários , Taiwan , Adulto Jovem
9.
J Med Imaging (Bellingham) ; 10(6): 066003, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074624

RESUMO

Purpose: Various laboratory sources have recently achieved progress in implementing deep learning models on biomedical optical imaging of soft biological tissues. The highly scattered nature of tissues at specific optical wavelengths results in poor spatial resolution. This opens up opportunities for diffuse optical imaging to improve the spatial resolution of obtained optical properties suffering from artifacts. This study aims to investigate a dual-encoder deep learning model for successfully detecting tumors in different phantoms w.r.t tumor size on diffuse optical imaging. Approach: Our proposed dual-encoder network extends U-net by adding a parallel branch of signal data to get information directly from the base source. This allows the trained network to localize the inclusions without degrading or merging with the background. The signals from the forward model and the images from the inverse problem are combined in a single decoder, filling the gap between existing direct processing and post-processing. Results: Absorption and reduced scattering coefficients are well reconstructed in both simulation and phantom test datasets. The proposed and implemented dual-encoder networks characterize better optical-property images than the signal-encoder and image-encoder networks, and the contrast-and-size detail resolution of the dual-encoder networks outperforms the other two approaches. From the measures of performance evaluation, the structural similarity and peak signal-to-noise ratio of the reconstructed images obtained by the dual-encoder networks remain the highest values. Conclusions: In this study, we synthesized the advantages of boundary data direct reconstruction, namely the extracted signals and iterative methods, from the obtained images into a unified network architecture.

10.
J Biomed Opt ; 28(2): 026001, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36761256

RESUMO

Significance: The machine learning (ML) approach plays a critical role in assessing biomedical imaging processes especially optical imaging (OI) including segmentation, classification, and reconstruction, intending to achieve higher accuracy efficiently. Aim: This research aims to develop an end-to-end deep learning framework for diffuse optical imaging (DOI) with multiple datasets to detect breast cancer and reconstruct its optical properties in the early stages. Approach: The proposed Periodic-net is a nondestructive deep learning (DL) algorithm for the reconstruction and evaluation of inhomogeneities in an inverse model with high accuracy, while boundary measurements are calculated by solving a forward problem with sources/detectors arranged uniformly around a circular domain in various combinations, including 16 × 15 , 20 × 19 , and 36 × 35 boundary measurement setups. Results: The results of image reconstruction on numerical and phantom datasets demonstrate that the proposed network provides higher-quality images with a greater amount of small details, superior immunity to noise, and sharper edges with a reduction in image artifacts than other state-of-the-art competitors. Conclusions: The network is highly effective at the simultaneous reconstruction of optical properties, i.e., absorption and reduced scattering coefficients, by optimizing the imaging time without degrading inclusions localization and image quality.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Algoritmos , Imagem Óptica , Imagens de Fantasmas , Aprendizado de Máquina , Processamento de Imagem Assistida por Computador/métodos
11.
Biomed Pharmacother ; 159: 114219, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621144

RESUMO

The medicinal properties of natural/edible plant products and their use are popular in traditional practice owing to their nutritional contents with little to no side effects. Lepista nuda (L. nuda), an edible mushroom (Clitocybe nuda, commonly known as blewit), has attracted researchers to evaluate its contents and the mechanism of its activities. In the current study, we focused on evaluating the antiangiogenic effects of L. nuda water extract on zebrafish development and in vitro human umbilical vein endothelial cell (HUVEC) tube formation. Bioactive components such as ergothioneine, eritadenine, and adenosine were identified and quantified by HPLC analysis. The L. nuda extract showed antiangiogenic properties and inhibited intersegmental vessel (ISV), caudal vein plexus (CVP), hyaloid vessel (HV), and subintestinal vessel (SIV) development in Tg (fli1: EGFP) zebrafish embryos. The expression of angiogenesis-related genes (vegfaa, kdrl, vegfba, flt1, kdr) was affected following L. nuda extract treatment. L. nuda extract attenuated in vitro HUVEC tube formation, migration, and invasion. Furthermore, inhibition of MAPK/p38 signaling and depletion of proangiogenic genes, including growth factors (fgf, ang2, and vegfa); primary and accessory receptors (tie2, vegfr2, and eng); MMPs (mmp1 and mmp2); and cytokines (il-1α, il-1ß, il-6, and tnf-α) was observed in HUVECs following L. nuda treatment. An in vivo zebrafish xenograft assay showed that L. nuda extract inhibited HuCCT1 cell-induced SIV sprouting in HuCCT1-injected embryos. Collectively, the results suggest that L. nuda could be a potential inhibitor of angiogenesis limiting cancer progression.


Assuntos
Agaricales , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/metabolismo , Células Endoteliais da Veia Umbilical Humana , Neovascularização Fisiológica , Inibidores da Angiogênese , Proliferação de Células , Movimento Celular
12.
Biochim Biophys Acta ; 1810(5): 504-13, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21376104

RESUMO

BACKGROUND: Histone deacetylase (HDAC) inhibitors were demonstrated to induce cell cycle arrest, promote cell differentiation or apoptosis, and inhibit metastasis. HDAC inhibitors have thus emerged as a new class of anti-tumor agents for various types of tumors. However, the mechanisms by which HDAC inhibition-induced cell death remain to be fully defined. METHODS: In the present study, we explored the apoptotic actions of trichostatin A (TSA), a HDAC inhibitor, in C6 glioma cells. RESULTS: TSA activated p38 mitogen-activated protein kinase (p38MAPK), leading to p53 phosphorylation and activation. P53, a proapoptotic transcription factor, in turn transactivated the expression of a proapoptotic protein, Bax. In addition, survivin, a member of inhibitor of apoptotic protein, was significantly decreased in TSA-treated C6 cells. P53 recruited to the endogenous survivin promoter region was increased and accompanied by decreasing recruitment of SP1 in response to TSA. TSA was also shown to induce IKK dephosphorylation and to suppress NF-κB reporter activity. CONCLUSIONS: TSA may cause C6 cell apoptosis through activating p38MAPK-p53 cascade resulting in Bax expression and survivin suppression. Negative regulation of IKK-NF-κB signaling may also lead to p53 activation and contribute to TSA apoptotic actions. GENERAL SIGNIFICANCE: TSA-induced p53 activation may occur through p53 modification by phosphorylation or by acetylation via IKK inactivation. The present study delineates, in part, the signaling pathways involved in TSA-induced glioma cell death.


Assuntos
Apoptose/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Imunoprecipitação da Cromatina , Relação Dose-Resposta a Droga , Citometria de Fluxo , Glioma/metabolismo , Glioma/patologia , Inibidores de Histona Desacetilases/farmacologia , Quinase I-kappa B/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Modelos Biológicos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica , Ratos , Survivina , Fatores de Tempo , Proteína X Associada a bcl-2/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Biochim Biophys Acta ; 1810(12): 1160-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21911040

RESUMO

BACKGROUND: Histone deacetylase (HDAC) inhibitors have emerged as a new class of antitumor agents because they were demonstrated to induce cell cycle arrest, promote cell apoptosis, and inhibit metastasis. Recently, HDAC inhibitors were also shown to exhibit pronounced anti-inflammatory properties. However, the underlying mechanism contributing to the suppression of inflammatory responses by HDAC inhibitors remains to be fully defined. In the present study, we explored the actions of trichostatin A (TSA), a potent HDAC inhibitor, on lipopolysaccharide (LPS)-induced cyclooxygenase (COX)-2 expression in human umbilical vascular endothelial cells (HUVECs). METHODS: HUVECs were exposed to LPS in the absence or presence of TSA. COX-2 expression and signaling molecules (JNK, p38MAPK and c-jun) activated by LPS were assessed. RESULTS: The LPS-induced cox-2 messenger RNA and protein were markedly suppressed by TSA. TSA inhibited JNK and p38MAPK phosphorylation in cells exposed to LPS. Treatment of cells with a JNK signaling inhibitor (JNK inhibitor II) or a p38MAPK inhibitor (p38MAPK inhibitor III) markedly inhibited LPS-induced COX-2 expression. TSA suppression of JNK and p38MAPK phosphorylation and subsequent COX-2 expression were restored by selective inhibition of MKP-1 using MKP-1 siRNA. In addition, TSA caused an increase in MKP-1 phosphatase activity in HUVECs. In conclusion, TSA may cause MKP-1 activation to dephosphorylate JNK and p38MAPK, leading to the downregulation of COX-2 in HUVECs stimulated by LPS, a proinflammatory stimulus. GENERAL SIGNIFICANCE: MKP-1 contributes to TSA's protective actions in HUVECs exposed to LPS. The present study also supports the therapeutic value of TSA in treating inflammatory vascular diseases.


Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Fosfatase 1 de Especificidade Dupla/metabolismo , Endotélio Vascular/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Veias Umbilicais/efeitos dos fármacos , Sequência de Bases , Western Blotting , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Primers do DNA , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Humanos , Fosforilação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias Umbilicais/citologia , Veias Umbilicais/enzimologia
14.
Front Psychol ; 13: 871274, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186381

RESUMO

In this article we describe four previous Tai-Chi models based on the I-Ching (Book of Changes) and their limitations. The I-Ching, the most important ancient source of information on traditional Chinese culture and cosmology, provides the metaphysical foundation for this culture, especially Confucian ethics and Taoist morality. To overcome the limitations of the four previous Tai-Chi models, we transform I-Ching cultural system into a psychological theory by applying the cultural system approach. Specifically, we propose the Jun-zi () Self-Cultivation Model (JSM), which argues that an individual (, xiao-ren) can become an ideal person, or jun-zi, through the process of self-cultivation, leading to good fortune and the avoidance of disasters (, qu-ji bi-xiong). The state of jun-zi is that of the well-functioning self, characterized by achieving one's full potential and an authentic, durable sense of wellbeing. In addition, we compare egoism (xiao-ren) and jun-zi as modes of psychological functioning. The JSM can be used to as a framework to explain social behavior, improve mental health, and develop culturally sensitive psychotherapies in Confucian culture. Finally, an examination of possible theoretical directions, clinical applications, and future research is provided.

15.
Biomedicines ; 10(5)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35625777

RESUMO

We demonstrate a working prototype of an optical breast imaging system involving parallel-plate architecture and a dual-direction scanning scheme designed in combination with a mammography machine; this system was validated in a pilot study to demonstrate its application in imaging healthy and malignant breasts in a clinical environment. The components and modules of the self-developed imaging system are demonstrated and explained, including its measuring architecture, scanning mechanism, and system calibration, and the reconstruction algorithm is presented. Additionally, the evaluation of feature indices that succinctly demonstrate the corresponding transmission measurements may provide insight into the existence of malignant tissue. Moreover, five cases are presented including one subject without disease (a control measure), one benign case, one suspected case, one invasive ductal carcinoma, and one positive case without follow-up treatment. A region-of-interest analysis demonstrated significant differences in absorption between healthy and malignant breasts, revealing the average contrast between the abnormalities and background tissue to exceed 1.4. Except for ringing artifacts, the average scattering property of the structure densities was 0.65-0.85 mm-1.

16.
Pharmaceutics ; 13(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34575572

RESUMO

Breast cancer remains the most frequently diagnosed cancer and is the leading cause of neoplastic disease burden for females worldwide, suggesting that effective therapeutic and/or diagnostic strategies are still urgently needed. In this study, a type of indocyanine green (ICG) and camptothecin (CPT) co-loaded perfluorocarbon double-layer nanocomposite named ICPNC was developed for detection and photochemotherapy of breast cancer. The ICPNCs were designed to be surface modifiable for on-demand cell targeting and can serve as contrast agents for fluorescence diffuse optical tomography (FDOT). Upon near infrared (NIR) irradiation, the ICPNCs can generate a significantly increased production of singlet oxygen compared to free ICG, and offer a comparable cytotoxicity with reduced chemo-drug dosage. Based on the results of animal study, we further demonstrated that the ICPNCs ([ICG]/[CPT] = 40-/7.5-µM) in association with 1-min NIR irradiation (808 nm, 6 W/cm2) can provide an exceptional anticancer effect to the MDA-MB-231 tumor-bearing mice whereby the tumor size was significantly reduced by 80% with neither organ damage nor systemic toxicity after a 21-day treatment. Given a number of aforementioned merits, we anticipate that the developed ICPNC is a versatile theranostic nanoagent which is highly promising to be used in the clinic.

17.
Front Oncol ; 9: 1188, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781495

RESUMO

Background and purpose: Angiogenesis and lymphangiogenesis are major routes for metastatic spread of tumor cells. It thus represent the rational targets for therapeutic intervention of cancer. Recently, we showed that a novel aliphatic hydroxamate-based compound, WMJ-S-001, exhibits anti-angiogenic, anti-inflammatory and anti-tumor properties. However, whether WMJ-S-001 is capable of suppressing lymphangiogenesis remains unclear. We are thus interested in exploring WMJ-S-001's anti-lymphangiogenic mechanisms in lymphatic endothelial cell (LECs). Experimental approach: WMJ-S-001's effects on LEC proliferation, migration and invasion, as well as signaling molecules activation were analyzed by immunoblotting, flow-cytometry, MTT, BrdU, migration and invasion assays. We performed tube formation assay to examine WMJ-S-001's ex vivo anti-lymphangiogenic effects. Key results: WMJ-S-001 inhibited serum-induced cell proliferation, migration, invasion in murine LECs (SV-LECs). WMJ-S-001 reduced the mRNA and protein levels of survivin. Survivin siRNA significantly suppressed serum-induced SV-LEC invasion. WMJ-S-001 induced p53 phosphorylation and increased its reporter activities. In addition, WMJ-S-001 increased p53 binding to the promoter region of survivin, while Sp1 binding to the region was decreased. WMJ-S-001 induced p38 mitogen-activated protein kinase (p38MAPK) activation. p38MPAK signaling blockade significantly inhibited p53 phosphorylation and restored survivin reduction in WMJ-S-001-stimulated SV-LCEs. Furthermore, WMJ-S-001 induced survivin reduction and inhibited cell proliferation, invasion and tube formation of primary human LECs. Conclusions and Implications: These observations indicate that WMJ-S-001 may suppress lymphatic endothelial remodeling and reduce lymphangiogenesis through p38MAPK-p53-survivin signaling. It also suggests that WMJ-S-001 is a potential lead compound in developing novel agents for the treatment of lymphangiogenesis-associated diseases and cancer.

18.
Front Pharmacol ; 9: 167, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29545751

RESUMO

Growing evidence shows that hydroxamate-based compounds exhibit broad-spectrum pharmacological properties including anti-tumor activity. However, the precise mechanisms underlying hydroxamate derivative-induced cancer cell death remain incomplete understood. In this study, we explored the anti-tumor mechanisms of a novel aliphatic hydroxamate-based compound, WMJ-J-09, in FaDu head and neck squamous cell carcinoma (HNSCC) cells. WMJ-J-09 induced G2/M cell cycle arrest and apoptosis in FaDu cells. These actions were associated with liver kinase B1 (LKB1), AMP-activated protein kinase (AMPK) and p38 mitogen-activated protein kinase (p38MAPK) activation, transcription factor p63 phosphorylation, as well as modulation of p21 and survivin. LKB1-AMPK-p38MAPK signaling blockade reduced WMJ-J-09's enhancing effects in p63 phosphorylation, p21 elevation and survivin reduction. Moreover, WMJ-J-09 caused an increase in α-tubulin acetylation and interfered with microtubule assembly. Furthermore, WMJ-J-09 suppressed the growth of subcutaneous FaDu xenografts in vivo. Taken together, WMJ-J-09-induced FaDu cell death may involve LKB1-AMPK-p38MAPK-p63-survivin signaling cascade. HDACs inhibition and disruption of microtubule assembly may also contribute to WMJ-J-09's actions in FaDu cells. This study suggests that WMJ-J-09 may be a potential lead compound and warrant the clinical development in the treatment of HNSCC.

19.
Sci Rep ; 7: 46847, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28589953

RESUMO

This corrects the article DOI: 10.1038/srep15796.

20.
Br J Pharmacol ; 174(17): 2941-2961, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28646512

RESUMO

BACKGROUND AND PURPOSE: Histone deacetylase (HDAC) inhibitors have been demonstrate to have broad-spectrum anti-tumour properties and have attracted lots of attention in the field of drug discovery. However, the underlying anti-tumour mechanisms of HDAC inhibitors remain incompletely understood. In this study, we aimed to characterize the underlying mechanisms through which the novel hydroxamate-based HDAC inhibitor, WMJ-8-B, induces the death of MDA-MB-231 breast cancer cells. EXPERIMENTAL APPROACH: Effects of WMJ-8-B on cell viability, cell cycle distribution, apoptosis and signalling molecules were analysed by the MTT assay, flowcytometric analysis, immunoblotting, reporter assay, chromatin immunoprecipitation analysis and use of siRNAs. A xenograft model was used to determine anti-tumour effects of WMJ-8-B in vivo. KEY RESULTS: WMJ-8-B induced survivin reduction, G2/M cell cycle arrest and apoptosis in MDA-MB-231 cells. STAT3 phosphorylation, transactivity and its binding to the survivin promoter region were reduced in WMJ-8-B-treated cells. WMJ-8-B activated the protein phosphatase SHP-1 and when SHP-1 signalling was blocked, the effects of WMJ-8-B on STAT3 phosphorylation and survivin levels were abolished. However, WMJ-8-B increased the transcription factor Sp1 binding to the p21 promoter region and enhanced p21 levels. Moreover, WMJ-8-B induced α-tubulin acetylation and disrupted microtubule assembly. Inhibition of HDACs was shown to contribute to WMJ-8-B's actions. Furthermore, WMJ-8-B suppressed the growth of MDA-MB-231 xenografts in mammary fat pads in vivo. CONCLUSIONS AND IMPLICATIONS: The SHP-1-STAT3-survivin and Sp1-p21 cascades are involved in WMJ-8-B-induced MDA-MB-231 breast cancer cell death. These results also indicate the potential of WMJ-8-B as a lead compound for treatment of breast cancer and warrant its clinical development.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Compostos Policíclicos/farmacologia , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Ácidos Hidroxâmicos/química , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos Nus , Compostos Policíclicos/química , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Survivina
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