Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
BMC Cancer ; 15: 1003, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26698299

RESUMO

BACKGROUND: Thyroid cancer has been indicated to have a higher global proportion of DNA methylation and a decreased level of histone acetylation. Previous studies showed that histone gene reviser and epigenetic changes role significant parts in papillary and anaplastic thyroid cancer tumorigenesis. The goal of this research was to study the endoplasmic reticulum (ER) stress-mediated actions of the dominant histone deacetylase (HDAC) inhibitor, N-hydroxy-7-(2-naphthylthio) hepatonomide (HNHA), in thyroid cancer and to explore its effects on apoptotic cell death pathways. METHODS: Experiments were achieved to conclude the effects of HNHA in papillary thyroid cancer (PTC) and anaplastic thyroid cancer (ATC) cell lines and xenografts, as compared with two other established HDAC inhibitors (SAHA; suberoylanilide hydroxamic acid and TSA; trichostatin A). RESULTS: Apoptosis, which was induced by all HDAC inhibitors, was particularly significant in HNHA-treated cells, where noticeable B-cell lymphoma-2 (Bcl-2) suppression and caspase activation were observed both in vitro and in vivo. HNHA increased Ca(2+) release from the ER to the cytoplasm. ER stress-dependent apoptosis was induced by HNHA, suggesting that it induced caspase-dependent apoptotic cell death in PTC and ATC. PTC and ATC xenograft studies demonstrated that the antitumor and pro-apoptotic effects of HNHA were greater than those of the established HDAC inhibitors. These HNHA activities reflected its induction of caspase-dependent and ER stress-dependent apoptosis on thyroid cancer cells. CONCLUSIONS: The present study indicated that HNHA possibly provide a new clinical approach to thyroid cancers, including ATC.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Naftalenos/farmacologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Humanos , Imuno-Histoquímica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
2.
Phytother Res ; 28(9): 1374-82, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24638915

RESUMO

The fruit of hassaku (Citrus hassaku Hort. ex Tanaka) is locally known as phalsak in Korea. Recently, the fruit extract has been known to exhibit in vivo preventive effects against UVB-induced pigmentation, antiallergic activity, and enhancement of blood fluidity. However, the exact mechanisms of how supercritical extracts of phalsak peel (SEPS) inhibits tumor metastasis and invasion are still not fully understood. We found that SEPS could downregulate the constitutive expression of both CXCR4 and HER2 in human breast cancer MDA-MB-231 cells as compared with other cells. SEPS also suppressed matrix metalloproteinase-9 (MMP-9) expression and its enzymatic activity under non-cytotoxic concentrations. Neither proteasome inhibition nor lysosomal stabilization had any effect on the SEPS-induced decrease in CXCR4 expression. A detailed study of the underlying molecular mechanisms revealed that the regulation of the downregulation of CXCR4 was at the transcriptional level, as indicated by downregulation of mRNA expression, suppression of NF-κB activity, and inhibition of chromatin immunoprecipitation activity. Suppression of CXCR4 expression by SEPS correlated with the inhibition of CXCL12-stimulated invasion of MDA-MB-231 cells. Overall, our results indicate, for the first time, that SEPS can suppress CXCR4 and MMP-9 expressions through blockade of NF-κB activation and thus has the potential to suppress metastasis of breast cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Citrus/química , Metaloproteinase 9 da Matriz/metabolismo , Extratos Vegetais/farmacologia , Receptores CXCR4/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Feminino , Frutas/química , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Fator de Transcrição RelA/metabolismo
3.
Phytother Res ; 28(3): 423-31, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23686889

RESUMO

The oncogenic PI3K/Akt/mammalian target of rapamycin (mTOR) signaling axis and its downstream effector, the ribosomal protein S6 kinase 1 (S6K1) play a key role in mediating cell survival in various tumor cells. Here, we investigated the effects of brassinin (BSN), a phytoalexin first identified as a constituent of cabbage, on the PI3K/Akt/mTOR/S6K1 activation, cellular proliferation, and apoptosis in PC-3 human prostate cancer. BSN exerted a significant dose-dependent cytotoxicity and reduced constitutive phosphorylation of Akt against androgen-independent PC-3 cells as compared to androgen-dependent LNCaP cells. Moreover, knockdown of androgen receptor (AR) by small interfering RNA enhanced the potential effect of BSN on induction of apoptosis in LNCaP cells. BSN clearly suppressed the constitutive activation of PI3K/Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, TUNEL staining, loss of mitochondrial membrane potential, down-regulation of antiapoptotic and proliferative proteins, activation of caspase-3, and cleavage of PARP. Additionally, BSN could block broad-spectrum inhibition of PI3K/Akt/mTOR/S6K1 axes, and aberrant Akt activation by pcDNA3-myr-HA-Akt1 plasmid could not prevent the observed suppressive effect of BSN on constitutive mTOR activation. Finally, overexpression of Bcl-2 also attenuated BSN-mediated apoptosis in PC-3 cells. Taken together, our findings suggest that BSN can interfere with multiple signaling cascades involved in tumorigenesis and might be provided as a potential therapeutic candidate for both the prevention and treatment of prostate cancer.


Assuntos
Apoptose/efeitos dos fármacos , Indóis/farmacologia , Neoplasias da Próstata/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiocarbamatos/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Humanos , Masculino , Potencial da Membrana Mitocondrial , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Poli(ADP-Ribose) Polimerases/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
4.
Prostate ; 73(3): 296-305, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22887478

RESUMO

BACKGROUND: Akt/mTOR/S6K1 signaling cascades play an important role both in the survival and proliferation of tumor cells. METHODS: In the present study, we investigated the effects of embelin (EB), identified primarily from the Embelia ribes plant, on the Akt/mTOR/S6K1 activation, associated gene products, cellular proliferation, and apoptosis in human prostate cancer cells. RESULTS: EB exerted significant cytotoxic and suppressive effects on Akt and mTOR activation against androgen-independent PC-3 cells as compared to androgen-dependent LNCaP cells. Moreover, EB suppressed the constitutive activation of Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, down-regulation of anti-apoptotic (Bcl-2, Bcl-xL, survivin, IAP-1, and IAP-2) and proliferative (cyclin D1) proteins, activation of caspase-3, and cleavage of PARP. We also observed that EB can significantly enhance the apoptotic effects of a specific pharmacological Akt inhibitor when used in combination and also caused broad inhibition of all the three kinases in Akt/mTOR/S6K1 signaling axis in PC-3 cells. CONCLUSIONS: EB inhibits multiple signaling cascades involved in tumorigenesis and can be used as a potential therapeutic candidate for both the prevention and treatment of prostate cancer.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Androgênios/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fatores de Tempo
5.
J Hum Genet ; 58(9): 604-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23803580

RESUMO

Methylation-specific (MS) multiplex ligation-dependent probe amplification (MLPA) at two differentially methylated regions (DMRs) at chromosome 11p15, H19-DMR and LIT1-DMR, and microsatellite analysis for uniparental disomy (UPD) at chromosome 7 or 11, have been recommended for the genetic diagnosis of the Beckwith-Wiedemann syndrome (BWS) and the Silver-Russell syndrome (SRS). In this study, the efficacy of the MS pyrosequencing method at H19-DMR and LIT1-DMR at 11p15 and SGCE-DMR at 7q21 was evaluated for the genetic diagnosis of BWS (n=18) and SRS (n=20) patients. Epigenetic alterations or UPD were detected in 83% of BWS and 50% of SRS individuals by MS-MLPA, but the detection rate increased to 95% of BWS and 70% of SRS by MS pyrosequencing. Thirteen BWS patients (72%) harbored loss-of-methylation (LOM) at LIT1-DMR and two patients (11%) harbored gain-of-methylation (GOM) at H19-DMR, whereas two patients (11%) had both LOM at LIT1-DMR and GOM at H19-DMR, reflecting paternal UPD 11. Thirteen SRS patients (65%) harbored LOM at H19-DMR, whereas one patient (5%) had GOM at SGCE-DMR, reflecting maternal UPD 7. Birth anthropometric profiles were significantly correlated to methylation scores at either H19-DMR or LIT1-DMR. In conclusion, MS pyrosequencing enhanced the detection rate of molecular defects in BWS and SRS. Moreover, it indicates that methylation status at 11p15.5 might have an important role in fetal growth.


Assuntos
Síndrome de Beckwith-Wiedemann/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 7/genética , Metilação de DNA/genética , Síndrome de Silver-Russell/genética , Síndrome de Beckwith-Wiedemann/diagnóstico , Análise Mutacional de DNA , Epigênese Genética , Feminino , Humanos , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase Multiplex , Linhagem , Síndrome de Silver-Russell/diagnóstico
6.
Chemphyschem ; 14(12): 2698-703, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-23784818

RESUMO

We have used grand canonical Monte Carlo simulations with a first-principles-based force field to show that metal-organic frameworks (MOFs) with Li functional groups (i.e. C-Li bonds) allow for exceptional H2 uptake at ambient temperature. For example, at 298 K and 100 bar, IRMOF-1-4Li shows a total H2 uptake of 5.54 wt% and MOF-200-27Li exhibits a total H2 uptake of 10.30 wt%, which are much higher than the corresponding values with pristine MOFs. Li-functionalized MOF-200 (MOF-200-27Li) shows 11.84 wt% H2 binding at 243 K and 100 bar. These hydrogen-storage capacities exceed the 2015 DOE target of 5.5 wt% H2. Moreover, the incorporation of Li functional groups into MOFs provides more benefits, such as higher delivery amount, for H2 uptake than previously reported Li-doped MOFs.


Assuntos
Hidrogênio/química , Lítio/química , Metais/química , Método de Monte Carlo , Temperatura
7.
Nature ; 482(7384): 162, 2012 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-22318594
8.
Phytother Res ; 27(1): 30-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22438130

RESUMO

Chrysanthemum indicum L. has been shown to possess antiinflammatory and anticancer activities, but its molecular targets/pathways are not yet fully understood in tumor cells. In the present study, the potential effects of C. indicum on signal transducer and activator of transcription 3 (STAT3) signaling pathway in different tumor cells were examined. The solvent fractions (hexane, CH2Cl2, EtOAc, and BuOH,) were obtained from a crude extract (80% EOH extract) of C. indicum. The methylene chloride fraction of C. indicum (MCI) exhibited strong cytotoxic activity as compared with the other fractions and clearly suppressed constitutive STAT3 activation against both DU145 and U266 cells, but not MDA-MB-231 cells. The suppression of constitutive STAT3 activation by MCI is associated with blocking upstream JAK1 and JAK2, but not Src. MCI downregulated the expression of STAT3-regulated gene products; this is correlated with the accumulation of the cell cycle at sub-G1 phase, the induction of caspase-3 activation, and apoptosis. Moreover, the major components of the MCI were bioactive compounds such as sudachitin, hesperetin, chrysoeriol, and acacetin. Sudachitin, chrysoeriol, and acacetin also exerted significantly cytotoxicity, clearly suppressed constitutive STAT3 activation, and induced apoptosis, although hesperetin did not show any significant effect in DU145 cells. Overall, our results demonstrate that MCI could induce apoptosis through inhibition of the JAK1/2 and STAT3 signaling pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Chrysanthemum/química , Extratos Vegetais/farmacologia , Neoplasias da Próstata/patologia , Fator de Transcrição STAT3/metabolismo , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 1/metabolismo , Janus Quinase 2/metabolismo , Masculino , Fosforilação , Transdução de Sinais/efeitos dos fármacos
9.
Pediatr Surg Int ; 29(12): 1327-40, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24072200

RESUMO

New development in the vascular network is a significant process for the proliferation, as well as metastatic expand, of cancer cells that depends on a sufficient provider of oxygen and nutrients and the removal of waste products. New blood and lymphatic vessels form via step called angiogenesis and lymphangiogenesis. Angiogenesis is controlled by activator and inhibitor of some molecules. So many different proteins have been established as angiogenic activators and inhibitors. Grades of expression of angiogenic factors demonstrate the forcefulness of tumor cells. The advance of angiogenic inhibitors should help to decrease both mortality and morbidity from carcinomas. So many patients have received anti-angiogenic therapy to date. Nevertheless, their notional efficacy and anti-angiogenic treatments have not demonstrated to be useful in terms of long-term survival. There is a crucial need for a new close treatment plan combining anti-angiogenic agents with standard cyto-reductive treatments in the regulation of cancer.


Assuntos
Inibidores da Angiogênese/farmacologia , Endostatinas/farmacologia , Xenoenxertos/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Animais , Compostos Bicíclicos com Pontes/farmacologia , Linhagem Celular , Humanos , Camundongos , Células Tumorais Cultivadas
10.
Int J Mol Sci ; 14(5): 8698-707, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23615465

RESUMO

A wet phase inversion process of polyamic acid (PAA) allowed fabrication of a porous membrane of polyimide (PI) with the combination of a low dielectric constant (1.7) and reasonable mechanical properties (Tensile strain: 8.04%, toughness: 3.4 MJ/m3, tensile stress: 39.17 MPa, and young modulus: 1.13 GPa), with further thermal imidization process of PAA. PAA was simply synthesized from purified pyromellitic dianhydride (PMDA) and 4,4-oxydianiline (ODA) in two different reaction solvents such as γ-butyrolactone (GBL) and N-methyl-2-pyrrolidinone (NMP), which produce Mw/PDI of 630,000/1.45 and 280,000/2.0, respectively. The porous PAA membrane was fabricated by the wet phase inversion process based on a solvent/non-solvent system via tailored composition between GBL and NMP. The porosity of PI, indicative of a low electric constant, decreased with increasing concentration of GBL, which was caused by sponge-like formation. However, due to interplay between the low electric constant (structural formation) and the mechanical properties, GBL was employed for further exploration, using toluene and acetone vs. DI-water as a coagulation media. Non-solvents influenced determination of the PAA membrane size and porosity. With this approach, insight into the interplay between dielectric properties and mechanical properties will inform a wide range of potential low-k material applications.


Assuntos
Derivados de Benzeno/química , Eletricidade , Imidas/química , Membranas Artificiais , Ftalimidas/química , Polímeros/química , Água/química , 4-Butirolactona/química , Microscopia Eletrônica de Varredura , Porosidade , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração
11.
Sci Rep ; 13(1): 1932, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732582

RESUMO

The human facial skeleton consists of multiple segments and causes difficulty during analytic processes. We developed image analysis software to quantify the amount of injury and validate the smooth curvature of the surface after facial bone reduction surgery. Three-dimensional computed tomography images of facial bone were obtained from 40 patients who had undergone open reduction surgery to treat unilateral zygomaticomaxillary fractures. Analytic software was developed based on the discrete curvature of a triangular mesh model. The discrete curvature values were compared before and after surgery using two regions of interest. For the inferior orbital rim, the weighted average of curvature changed from 0.543 ± 0.034 to 0.458 ± 0.042. For the anterior maxilla, the weighted average of curvature changed from 0.596 ± 0.02 to 0.481 ± 0.031, showing a significant decrement (P < 0.05). The curvature was further compared with the unaffected side using the Bray-Curtis similarity index (BCSI). The BCSI of the inferior orbital rim changed from 0.802 ± 0.041 to 0.904 ± 0.015, and that for the anterior maxilla changed from 0.797 ± 0.029 to 0.84 ± 0.025, demonstrating increased similarity (P < 0.05). In computational biology, adequate analytic software is crucial. The newly developed software demonstrated significant differentiation between pre- and postoperative curvature values. Modification of formulas and software will lead to further advancements.


Assuntos
Fraturas Cranianas , Telas Cirúrgicas , Humanos , Maxila/cirurgia , Tomografia Computadorizada por Raios X/métodos
14.
J Comput Aided Mol Des ; 26(11): 1267-75, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23104667

RESUMO

Using phage display technique, we identified tissue-targeting peptide sets that recognize specific tissues (bone-marrow dendritic cell, kidney, liver, lung, spleen and visceral adipose tissue). In order to rapidly evaluate tissue-specific targeting peptides, we performed machine learning studies for predicting the tissue-specific targeting activity of peptides on the basis of peptide sequence information using four machine learning models and isolated the groups of peptides capable of mediating selective targeting to specific tissues. As a representative liver-specific targeting sequence, the peptide "DKNLQLH" was selected by the sequence similarity analysis. This peptide has a high degree of homology with protein ligands which can interact with corresponding membrane counterparts. We anticipate that our models will be applicable to the prediction of tissue-specific targeting peptides which can recognize the endothelial markers of target tissues.


Assuntos
Inteligência Artificial , Medula Óssea/metabolismo , Células Dendríticas/metabolismo , Fígado/metabolismo , Fragmentos de Peptídeos/química , Animais , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos , Fragmentos de Peptídeos/farmacologia , Biblioteca de Peptídeos , Ligação Proteica , Curva ROC , Ratos , Ratos Sprague-Dawley , Ratos Wistar
15.
Immunopharmacol Immunotoxicol ; 34(2): 282-91, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21854107

RESUMO

Patrinia scabiosaefolia (PS) has been used for curing various types of inflammatory-related disorders. However, the precise mechanism of the anti-inflammatory activity of PS remains unclear. Here, we investigated the anti-inflammatory effects of several fractions isolated from the PS in RAW 264.7 macrophages. The results indicated that the ethyl acetate fraction of PS (EAPS) concentration highly suppressed lipopolysaccharide (LPS)-induced nitric oxide (NO) and IL-6 productions without a cytotoxic effect on RAW 264.7 cells. EAPS inhibited the expressions of LPS-induced iNOS and COX-2 protein and their mRNA in a dose-dependent manner. Particularly, EAPS suppressed the level of nuclear factor-κB (NF-κB) activity, which was linked with the suppression of LPS-induced phosphorylation of p65 at serine 276 and p65 translocation into nuclei, but not MAPK signaling. In addition, treatment with EAPS inhibited the production of TNF-α in LPS-injected mice and suppressed the production of IL-6 and TNF-α in LPS-stimulated splenocytes from BALB/c mice. Therefore, we demonstrate here that Patrinia scabiosaefolia potentially inhibits the biomarkers related to inflammation through the blocking of NF-κB p65 activation, and it may be a potential therapeutic candidate for the treatment of inflammatory diseases.


Assuntos
Acetatos/química , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Patrinia/química , Extratos Vegetais/farmacologia , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Interleucina-6/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Baço/citologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Immunopharmacol Immunotoxicol ; 34(5): 768-78, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22299827

RESUMO

Emodin (ED), an anthraquinone derivative, has been found to inhibit proliferation, induce apoptosis, suppress angiogenesis, impede metastasis, and enhance chemotherapy. However, the detailed mechanism of ED related to the regulation of CXC chemokine receptor-4 (CXCR4) gene expression that affects cellular migration and invasion in prostate and lung cancer cells are not fully understood. Recent evidence indicates that the CXCR4/CXCL12 axis is involved in promoting invasion and metastasis in tumors. Thus, novel agents that can downregulate CXCR4 expression have therapeutic potential in repressing cancer metastasis. Among ED and its derivatives, it is found that ED downregulated the expression of both CXCR4 and HER2 without affecting cell viability in tumor cells. The suppression of CXCR4 expression by ED was found to correlate with the inhibition of CXCL12-induced migration and invasion of both DU145 and A549 cells. Besides, neither proteasome inhibition nor lysosomal stabilization had any effect on ED-induced decrease in CXCR4 expression. The basic molecular mechanisms unveiled that the downregulation of CXCR4 was at the transcriptional level, as indicated by downregulation of mRNA expression and suppression of NF-κB activation. Overall, our findings suggest that ED is a novel blocker of CXCR4 expression and, thus, has enormous potential as a powerful therapeutic agent for metastatic cancer.


Assuntos
Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Emodina/farmacologia , Neoplasias Pulmonares/metabolismo , Neoplasias da Próstata/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores CXCR4/biossíntese , Linhagem Celular Tumoral , Quimiocina CXCL12/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , NF-kappa B/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Receptor ErbB-2/metabolismo , Transcrição Gênica/efeitos dos fármacos
17.
Pharm Biol ; 50(1): 8-17, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22149883

RESUMO

CONTEXT: Iridoids belong to a group of monoterpene compounds with cyclopentane ring and found as mostly the glycoside forms in nature. They act primarily as the defense substances and found in various medicinal plants. OBJECTIVE: Although many iridoids exhibit anti-inflammatory and anticancer activities, their molecular targets/pathways are not fully understood. Here, the antiproliferative effect of the hydrolyzed-iridoid product (H-iridoid) form through the STAT3 signaling pathways on tumor cells was investigated. MATERIALS AND METHODS: H-iridoids were obtained from five iridoid glycosides with ß-glucosidase treatment. The effects of several H-iridoids on cell viability and cell proliferation in tumor cells were measured by the MTT assay. The phosphorylation levels of STAT3, its regulatory molecules, and apoptosis by H-geniposide treatment in DU145 cells were investigated by immunoblots and flow cytometry. RESULTS: No single iridoid glycoside exerted any cytotoxicity in the tumor cells, whereas H-iridoids had significant cytotoxic, antiproliferative, and STAT3 inhibitory effects and revealed different potencies depending on their chemical structures. Among the H-iridoids tested, H-geniposide inhibited constitutive STAT3 activation through inhibiting upstream JAK1 and c-Src. Consistent with STAT3 inactivation, H-geniposide downregulated the expressions of Bcl-2, Bcl-xL, survivin, and cyclin D1; this correlated with the accumulation of cells in the sub-G1 phase of the cell cycle and the induction of apoptosis. DISCUSSION AND CONCLUSIONS: Our results indicate that the hydrolysis of the glycosidic bond from iridoid glycoside is required for exhibiting cytotoxicity in tumor cells. H-geniposide is the most potent agent and a novel blocker of STAT3 activation in DU145 cells.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicosídeos Iridoides/farmacologia , Neoplasias/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Hidrólise , Glicosídeos Iridoides/química , Iridoides/química , Iridoides/farmacologia , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos
18.
Pharm Biol ; 50(10): 1210-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22853317

RESUMO

CONTEXT: Nobiletin is one of the citrus bioflavonoids and can be found in citrus fruits such as lemons, oranges, tangerines, and grapefruits. The most studied properties of nobiletin are its anti-inflammatory and anticancer activities. OBJECTIVE: The exact mechanisms of how nobiletin inhibits tumor metastasis and invasion are still not fully understood. In this study, we screened various natural compounds to down-modulate the CXC chemokine receptor-4 (CXCR4) and matrix metallopeptidase-9 (MMP-9). MATERIALS AND METHODS: The effect of nobiletin on the constitutive expressions of CXCR4 and MMP-9, MMP-9 enzymatic activity, associated nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) activation, and tumor cell invasion in human breast cancer cells was investigated. CXCR4 and MMP-9 expression were evaluated via reverse transcription polymerase chain reaction (RT-PCR) and western blotting. NF-κB activation was also evaluated by electrophoretic mobility shift assay (EMSA). In addition, the antimetastatic effects of nobiletin were determined by gelatin zymography and invasion assay. RESULTS: Nobiletin down-regulated both the constitutive expressions of CXCR4 and MMP-9 in human breast cancer cells with IC(50) values of 32 and 24 µM, respectively. Nobiletin also suppressed MMP-9 enzymatic activity and tumor cell invasion under noncytotoxic concentrations. Neither proteasome inhibition nor lysosomal stabilization had any effect on the nobiletin-induced decrease in CXCR4 expression. A detailed study of the underlying molecular mechanisms revealed that the regulation of the down-regulation of CXCR4 and MMP-9 were at the transcriptional level, as indicated by the down-regulation of mRNA expression and the suppression of the constitutive NF-κB and MAPKs activation. DISCUSSION AND CONCLUSION: Our results indicate, for the first time, that nobiletin is a novel blocker of CXCR4 and MMP-9 expressions and thus has the potential to suppress metastasis of breast cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Flavonas/farmacologia , Metaloproteinase 9 da Matriz/genética , Receptores CXCR4/genética , Antineoplásicos Fitogênicos/administração & dosagem , Western Blotting , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Ensaio de Desvio de Mobilidade Eletroforética , Flavonas/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Metástase Neoplásica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Front Microbiol ; 13: 1005415, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36601396

RESUMO

Polyurethane (PU), currently replacing existing synthetic materials worldwide, is a synthetic polymer derived from polyols, isocyanates, and a chain extender added by condensation reactions. PU wastes which are difficult to recycle, are commonly discarded in landfills and flow into ecosystems, thereby causing serious environmental problems. In recent years, insect-associated microbes have become a promising, eco-friendly strategy as an alternative to plastic recycling. This study aimed to evaluate the potential of Serratia sp. HY-72 strain isolated from the intestine of the Asian mantis (Hierodula patellifera) for PU degradation. The 65 kDa family I.3 lipase which degrades PU was identified and characterized, with a specific activity of 2,883 U mg-1. The bacterial filtrates and the recombinant lipase degraded Impranil (a colloidal polyester-PU dispersion, 100 g l-1) by 85.24 and 78.35% after 72 h incubation, respectively. Fourier transform infrared spectroscopy analysis revealed changes in Impranil functional groups, with decreased C=O functional group and aliphatic chain signals, and increased N-H bending with C-N stretching and C-O stretching. The current study also revealed that the HY-72 strain biodegraded the commercial PU foams (polyester- and polyether- PU) with 23.95 and 10.95% weight loss after 2 weeks, respectively with changes in surface morphology and structure such as cracks, roughness, and surface roughening. Altogether, this is one of the few studies reporting biodegradation of PU by the insect-associated microbe. These findings suggest that the insect-associated microbe could be a promising resource for biodegradation and recycling of plastic waste.

20.
J Biol Chem ; 285(15): 11584-95, 2010 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-20145250

RESUMO

Cellular oxygen sensing is required for hypoxia-inducible factor-1alpha stabilization, which is important for tumor cell survival, proliferation, and angiogenesis. Here we find that terpestacin, a small molecule previously identified in a screen of microbial extracts, binds to the 13.4-kDa subunit (UQCRB) of mitochondrial Complex III, resulting in inhibition of hypoxia-induced reactive oxygen species generation. Consequently, such inhibition blocks hypoxia-inducible factor activation and tumor angiogenesis in vivo, without inhibiting mitochondrial respiration. Overexpression of UQCRB or its suppression using RNA interference demonstrates that it plays a crucial role in the oxygen sensing mechanism that regulates responses to hypoxia. These findings provide a novel molecular basis of terpestacin targeting UQCRB of Complex III in selective suppression of tumor progression.


Assuntos
Proteínas de Transporte/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Hipóxia , Mitocôndrias/metabolismo , Neovascularização Patológica , Oxigênio/metabolismo , Espécies Reativas de Oxigênio , Animais , Compostos Bicíclicos com Pontes/farmacologia , Endotélio Vascular/citologia , Feminino , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Fator A de Crescimento do Endotélio Vascular/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA