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1.
Chin J Physiol ; 65(3): 125-135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35775531

RESUMO

Cajanus cajan (L.) Millsp., known as pigeon pea, is one of the major grain legume crops of the tropical world. It recognizes as an ethnomedicine to possess various functions, such as helping in healing wound and cancer therapy. We investigated whether 95% ethanol extracts from C. cajan root (EECR) protect against methylglyoxal (MGO)-induced insulin resistance (IR) and hyperlipidemia in male Wistar rats and explored its possible mechanisms. The hypoglycemic potential of EECR was evaluated using α-amylase, α-glucosidase activities, and advanced glycation end products (AGEs) formation. For in vivo study, the rats were divided into six groups and orally supplemented with MGO except for Group 1 (controls). Group 2 was supplemented with MGO only, Group 3: MGO + metformin, Group 4: MGO + Low dose-EECR (L-EECR; 10 mg/kg bw), Group 5: MGO + Middle dose-EECR (M-EECR; 50 mg/kg bw), and Group 6: MGO + High dose-EECR (H-EECR; 100 mg/kg bw). EECR possessed good inhibition of α-glucosidase, α-amylase activities, and AGEs formation (IC50 = 0.12, 0.32, and 0.50 mg/mL), respectively. MGO significantly increased serum levels of blood glucose (GLU), glycosylated hemoglobin, homeostasis model assessment of IR, AGEs, lipid biochemical values, and atherogenic index, whereas EECR decreased these levels in a dose-dependent manner. EECR can also act as an insulin sensitizer, which significantly decreased (47%, P < 0.05) the blood GLU levels after intraperitoneal injection of insulin in the insulin tolerance tests. The hypoglycemic and antihyperlipidemic mechanisms of EECR are likely through several possible pathways including the inhibition of carbohydrate-hydrolyzing enzymes (α-glucosidase and α-amylase) and the enhancement of MGO-trapping effects on inhibition of AGEs formation.


Assuntos
Cajanus , Diabetes Mellitus Experimental , Animais , Cajanus/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Insulina , Óxido de Magnésio , Masculino , Aldeído Pirúvico/metabolismo , Aldeído Pirúvico/farmacologia , Ratos , Ratos Wistar , alfa-Amilases , alfa-Glucosidases
2.
Cell Mol Neurobiol ; 39(5): 591-604, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30852719

RESUMO

It is known that cerebral ischemia can cause brain inflammation and adiposome can serve as a depot of inflammatory mediators. In the study, the pro-inflammatory and pro-death role of adiposome in ischemic microglia and ischemic brain was newly investigated. The contribution of PPARγ to adiposome formation was also evaluated for the first time in ischemic microglia. Focal cerebral ischemia/reperfusion (I/R) animal model and the in vitro glucose-oxygen-serum deprivation (GOSD) cell model were both applied in the study. GOSD- or I/R-induced adiposome formation, inflammatory activity, cell death of microglia, and brain infarction were, respectively, determined, in the absence or presence of NS-398 (adiposome inhibitor) or GW9662 (PPARγ antagonist). GOSD-increased adiposome formation played a critical role in stimulating the inflammatory activity (production of TNF-α and IL-1ß) and cell death of microglia. Similar results were also found in ischemic brain tissues. GOSD-induced PPARγ partially contributed to the increase of adiposomes and adiposome-mediated inflammatory responses of microglia. Blockade of adiposome formation with NS-398 or GW9662 significantly reduced not only the inflammatory activity and death rate of GOSD-treated microglia but also the brain infarct volume and motor function deficit of ischemic rats. The pathological role of microglia-derived adiposome in cerebral ischemia has been confirmed and attributed to its pro-inflammatory and/or pro-death effect upon ischemic brain cells and tissues. Adiposome and its upstream regulator PPARγ were therefore as potential targets for the treatment of ischemic stroke. Therapeutic values of NS-398 and GW9662 have been suggested.


Assuntos
Isquemia Encefálica/terapia , Gotículas Lipídicas/metabolismo , Microglia/metabolismo , Acidente Vascular Cerebral/terapia , Anilidas/farmacologia , Animais , Animais Recém-Nascidos , Isquemia Encefálica/complicações , Morte Celular , Meios de Cultura Livres de Soro , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Glucose/deficiência , Inflamação/patologia , Interleucina-1beta/metabolismo , Masculino , Microglia/patologia , Atividade Motora/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Nitrobenzenos/farmacologia , Oxigênio , PPAR gama/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/terapia , Acidente Vascular Cerebral/complicações , Sulfonamidas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
3.
Eur J Haematol ; 103(4): 417-425, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31356696

RESUMO

OBJECTIVES: This study explored resistance functions and their interactions in de novo AML treated with the "7 + 3" induction regimen. METHODS: We analyzed RNA-sequencing profiles of whole bone marrow samples from 52 de novo AML patients who completed the "7 + 3" regimen and stratified patients into CR (n = 35) and non-CR (n = 17) groups. RESULTS: A systematic gene set analysis revealed significant associations between chemoresistance and mTOR (P < .001), myc (P < .001), mitochondrial oxidative phosphorylation (P < .001), and stemness (P = .002). These functions were independent with regard to gene contents and activity scores. An integration of these four functions showed a prediction of chemoresistance (area under the receiver operating characteristic curve = 0.815) superior to that of each function alone. Moreover, our proposed seven-gene scoring system significantly correlated with the four-function model (r = .97; P < .001) to predict chemoresistance to the "7 + 3" regimen. On multivariate analysis, a seven-gene score of ≥-0.027 (hazard ratio: 11.18; 95% confidence interval: 2.06-60.65; P = .005) was an independent risk factor for induction failure. CONCLUSIONS: Myc, OXPHOS, mTOR, and stemness were responsive for chemoresistance in AML. Treatments other than the "7 + 3" regimen need to be considered for de novo AML patients predicted to be refractory to the "7 + 3" regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores , Biomarcadores Tumorais , Células da Medula Óssea/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Resultado do Tratamento
4.
Int J Mol Sci ; 20(10)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137784

RESUMO

BACKGROUND AND AIMS: Liver fibrosis is the excessive accumulation of extracellular matrix proteins, including collagen, which occurs in most types of chronic liver diseases. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension. Activated hepatic perivascular stellate cells, portal fibroblasts, and myofibroblasts of bone marrow origin have been identified as major collagen-producing cells in the injured liver. These cells are activated by fibrogenic cytokines, such as TGF-ß1. The inhibition of TGF-ß1 function or synthesis is a major target for the development of antifibrotic therapies. Our previous study showed that the water and ethanol extracts of Graptopetalum paraguayense (GP), a Chinese herbal medicine, can prevent dimethylnitrosamine (DMN)-induced hepatic inflammation and fibrosis in rats. METHODS: We used rat hepatic stellate HSC-T6 cells and a diethylnitrosamine (DEN)-induced rat liver injury model to test the potential mechanism of GP extracts and its fraction, HH-F3. RESULTS: We demonstrated that GP extracts and HH-F3 downregulated the expression levels of extracellular matrix (ECM) proteins and inhibited the proliferation and migration via suppression of the TGF-ß1 pathway in rat hepatic stellate HSC-T6 cells. Moreover, the HH-F3 fraction decreased hepatic collagen content and reduced plasma AST, ALT, and γ-GT activities in a DEN-induced rat liver injury model, suggesting that GP/HH-F3 has hepatoprotective effects against DEN-induced liver fibrosis. CONCLUSION: These findings indicate that GP/HH-F3 may be a potential therapeutic agent for the treatment of liver fibrosis. The inhibition of TGF-ß-mediated fibrogenesis may be a central mechanism by which GP/HH-F3 protects the liver from injury.


Assuntos
Crassulaceae/química , Cirrose Hepática/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular , Colágeno/genética , Colágeno/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Cirrose Hepática/metabolismo , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Transdução de Sinais , Fator de Crescimento Transformador beta/genética
5.
Int J Cancer ; 142(1): 92-108, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28884479

RESUMO

In this study, we firstly showed that p53 transcriptionally represses Aurora-A gene expression through directly binding to its promoter. DNA affinity precipitation assay and chromatin immunoprecipitation assay indicated that p53 physically bound to the Aurora-A promoter. Moreover, the in vitro and in vivo assays showed that p53 directly bound to the Aurora-A promoter together with histone deacetylase 1 (HDAC1) and mSin3a as corepressors. Furthermore, we identified that the nucleotides -360 to -354 (CCTGCCC), upstream of the Aurora-A transcriptional start site, was responsible for the p53-mediated repression. Mutation within this site disrupted its interaction with p53, mSin3a and HDAC1, as well as attenuated the repressive effect of p53 on Aurora-A promoter activity. Treatment with trichostatin A (TSA), a HDAC1 inhibitor, disrupted the interaction of p53-HDAC1-mSin3a complex with the nucleotides -365∼-345 region, and enhanced the Aurora-A promoter activity and gene expression. Additionally, knockdown of p53 or mSin3a also drastically blocked the formation of p53-HDAC1-mSin3a repressive complex onto this promoter region and elevated the Aurora-A promoter activity and gene expression. Moreover, the p53-HDAC1-mSin3a repressive complex also involved in the inhibition of Aurora-A gene expression upon cisplatin treatment. Finally, the clinical investigation showed that Aurora-A and p53 exhibited an inverse correlation in both the expression level and prognostic status, and the low p53/high Aurora-A showed the poorest prognosis of NSCLC patients. Our findings showed novel regulatory mechanisms of p53 in regulating Aurora-A gene expression in NSCLC cells.


Assuntos
Adenocarcinoma/genética , Aurora Quinase A/biossíntese , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pulmonares/genética , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/mortalidade , Aurora Quinase A/genética , Linhagem Celular Tumoral , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética
6.
J Pathol ; 237(1): 50-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25925728

RESUMO

Ghrelin is an appetite-regulating molecule that promotes growth hormone (GH) release and food intake through growth hormone secretagogue receptor (GHS-R). Recently, high ghrelin levels have been detected in various types of human cancer. Ghrelin expression is observed in proximal and distal renal tubules, where renal cell carcinoma (RCC) arises. However, whether ghrelin is up-regulated and promotes renal cell carcinogenesis remains obscure. In this study, we observed that ghrelin was highly expressed in renal tumours, especially in metastatic RCC. In addition, high ghrelin levels correlated with poor outcome, lymph node and distant metastasis. The addition of ghrelin promoted the migration ability of RCC cell lines 786-0, ACHN and A-498. Furthermore, knockdown of ghrelin expression reduced in vitro migration and in vivo metastasis, suggesting a requirement for ghrelin accumulation in the microenvironment for RCC metastasis. Analysis of microarray signatures using Ingenuity Pathway Analysis (IPA) and MetaCore pointed to the potential regulation by ghrelin of Snail, a transcriptional repressor of E-cadherin. We further observed that Ghrelin increased the expression, nuclear translocation and promoter-binding activity of Snail. Snail silencing blocked the ghrelin-mediated effects on E-cadherin repression and cell migration. Snail-E-cadherin regulation was mediated by GHS-R-triggered Akt phosphorylation at Ser473 and Thr308. Pretreatment with PI3K inhibitors, LY294002 and wortmannin, as well as Akt siRNA, decreased ghrelin-induced Akt phosphorylation, Snail promoter binding activity and migration. Taken together, our findings indicate that ghrelin can activate Snail function via the GHS-R-PI3K-Akt axis, which may contribute to RCC metastasis. The microarray raw data were retrieved from the Cancer Genome Atlas (TCGA) [KIRC gene expression (IlluminaHiSeq) dataset].


Assuntos
Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/secundário , Movimento Celular , Grelina/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Fatores de Transcrição/metabolismo , Animais , Antígenos CD , Sítios de Ligação , Caderinas/genética , Caderinas/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Grelina/genética , Humanos , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Regiões Promotoras Genéticas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail , Fatores de Tempo , Fatores de Transcrição/genética , Transfecção
7.
Chin J Physiol ; 59(6): 331-347, 2016 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-27817195

RESUMO

Lung resistance-related protein (LRP) is a human major vault protein (MVP) implicated in drug resistance of cancer cells in a cell-type dependent manner. The primary goal of the study was to understand the role(s) of LRP in doxorubicin (DOX) resistance of non-small cell lung cancer (NSCLC) cells and the underlying working mechanisms. In the study, the roles of LRP in the regulation of DOX dynamics, nuclear import of minor vault proteins (vault poly (ADP-ribose) polymerase, vPARP and telomerase associated protein-1, TEP-1) and DOX-mediated cytotoxicity were examined in CH27 and H460 cells. Our results were the first to show that the CH27 cells with higher LRP expression levels were more resistant to DOX-induced cytotoxicity as shown in apoptosis experiments. LRP at the nuclear membrane could regulate DOX efflux from the nucleus to the cytosol, and also the reverse vPARP/TEP1 influx from the cytosol, to protect NSCLC cells from DOX-induced apoptosis. Cytosolic LRP could bind to DOX, vPARP and TEP1 to clear DOX away from the nucleus and promote the assembly of vaults for cell protection again. Based on the data obtained, the molecular mechanisms responsible for DOX resistance of NSCLC were delineated to demonstrate that LRP, vPARP and TEP1 were potential targets for NSCLC therapy. Inhibitors of these proteins, including small interfering LRP (siLRP), wheat-germ agglutenin (WGA) (WGA), 3-aminobenzamide (3-AB) and 3,6,9-trisubstituted acridine 9-[4-(N,N-dimethylamino) phenylamino]-3,6-bis(3-pyrrolodinopropionamido) acridine (BRACO-19), break down the DOX resistance of NSCLC cells, particularly in CH27 cells, and may have therapeutic values in the control of NSCLC.


Assuntos
Antibióticos Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos/fisiologia , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas de Ligação a RNA
8.
Molecules ; 21(4): 513, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104503

RESUMO

Crude extracts of Sedum formosanum N.E.Br. obtained from n-butanol partition (BP) and isopropanol salting-out pretreatment (ISP) were analyzed using antioxidation assays. The results indicated that the extract from ISP contained more potent antioxidants and thus exhibited more antioxidant activity in all the assays. The superoxide radical-scavenging activity and inhibition of nitric oxide radicals achieved after ISP were 3.65 and 2.18 times higher than those achieved through BP, respectively. Eight bioactive natural products were isolated and identified according to an analysis of antioxidation activity in different fractions of the ISP crude extract, namely three cyanophoric glycosides 1-3, three flavonoids 4-6 and two phenolic compounds (7 and a new compound 8). Among them, compounds 5 and 6 exhibit the highest antioxidation capability, and the ISP is suitable for obtaining compounds 5 and 6 using HPLC chromatograms. Therefore, ISP is an excellent extraction technology that can be used to extract antioxidant compounds in the nutraceutical and pharmaceutical industries.


Assuntos
1-Butanol/química , 2-Propanol/química , Antioxidantes/farmacologia , Sedum/química , Antioxidantes/química , Indústria Farmacêutica/métodos , Flavonoides/química , Flavonoides/farmacologia , Oxirredução , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
9.
Cell Physiol Biochem ; 33(6): 1620-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24851929

RESUMO

BACKGROUND/AIMS: All-trans retinoic acid (ATRA), the active form of vitamin A, plays an important role in the growth arrest of numerous types of cancer cells. It has been indicated that cyclin-dependent kinase 5 (Cdk5) activity can be affected by ATRA treatment. Our previous results demonstrate the involvement of Cdk5 in the fate of prostate cancer cells. The purpose of this study is to examine whether Cdk5 is involved in ATRA-induced growth arrest of the castration-resistant cancer cell line DU145 through up-regulating Cdk inhibitor protein, p27. METHODS: DU145 cells were treated with ATRA, and cell proliferation, protein expression, and protein localization of Cdk5/p27 were examined. Cell proliferation and cell cycle distribution were also determined under Cdk5 inhibition induced by inhibitor or knockdown. RESULTS: ATRA treatment inhibited DU145 cell proliferation and significantly increased p27 expression through Cdk5 up-regulation. Immunocytochemical data showed that a Cdk5 inhibitor reduced ATRA-triggered nuclear distribution of p27 in DU145 cells. The proliferation inhibition and G1 phase accumulation of DU145 cells were significantly increased by ATRA treatment, whereas Cdk5 inhibitor and siRNA could reverse these effects. CONCLUSIONS: Our results demonstrate that ATRA induced growth inhibition in castration-resistant prostate cancer cells through activating Cdk5 and p27. We hope this finding will increase the knowledge of prostate cancer treatment and can be applied in patients' nutritional control in the future.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Quinase 5 Dependente de Ciclina/metabolismo , Tretinoína/farmacologia , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 5 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Microscopia Confocal , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Biochem Biophys Res Commun ; 437(1): 55-61, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23791833

RESUMO

The aim of this study is to investigate the relationship between paraoxonase 1 (PON1) and atherosclerosis-related inflammation. In this study, human hepatoma HepG2 cell line was used as a hepatocyte model to examine the effects of the pro-inflammatory cytokines on PON1 expression. The results showed that IL-6, but not TNF-α and IL-1ß, significantly increased both the function and protein level of PON1; data from real-time RT-PCR analysis revealed that the IL-6-induced PON1 expression occurred at the transcriptional level. Increase of IκB kinase activity and IκB phosphorylation, and reduction of IκB protein level were also observed in IL-6-treated HepG2 cells compared with untreated culture. This event was accompanied by increase of NF-κB-p50 and -p65 nuclear translocation. Moreover, treatment with IL-6 augmented the DNA binding activity of NF-κB. Furthermore, pharmacological inhibition of NF-κB activation by PDTC and BAY 11-7082, markedly suppressed the IL-6-mediated PON1 expression. In addition, IL-6 increased the levels of phosphorylated protein kinase B (PKB, AKT). An AKT inhibitor LY294002 effectively suppressed IKK/IκB/NF-κB signaling and PON1 gene expression induced by IL-6. Our findings demonstrate that IL-6 upregulates PON1 gene expression through an AKT/NF-κB signaling axis in human hepatocyte-derived HepG2 cell line.


Assuntos
Arildialquilfosfatase/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Interleucina-6/farmacologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Arildialquilfosfatase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células Hep G2 , Humanos , Interleucina-1beta/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
11.
Mol Carcinog ; 52(3): 183-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22086658

RESUMO

Pemetrexed, a new-generation antifolate, has demonstrated promising single-agent activity in front- and second-line treatments of non-small cell lung cancer. However, the molecular mechanism of pemetrexed-mediated antitumor activity remains unclear. The current study shows that pemetrexed induced DNA damage and caspase-2, -3, -8, and -9 activation in A549 cells and that treatment with caspase inhibitors significantly abolished cell death, suggesting a caspase-dependent apoptotic mechanism. The molecular events of pemetrexed-mediated apoptosis was associated with the activation of ataxia telangiectasia mutated (ATM)/p53-dependent and -independent signaling pathways, which promoted intrinsic and extrinsic apoptosis by upregulating Bax, PUMA, Fas, DR4, and DR5 and activating the caspase signaling cascade. Supplementation with dTTP allowed normal S-phase progression and rescued apoptotic death in response to pemetrexed. Overall, our findings reveal that the decrease of thymidylate synthase and the increase of Bax, PUMA, Fas, DR4, and DR5 genes may serve as biomarkers for predicting responsiveness to pemetrexed.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glutamatos/farmacologia , Guanina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspases/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Guanina/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Pemetrexede , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Nucleotídeos de Timina/farmacologia
12.
Ann Hematol ; 92(3): 301-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23180436

RESUMO

Acute myeloid leukaemia (AML) is a heterogeneous disease with dismal outcome. Sunitinib is an orally active inhibitor of multiple tyrosine kinase receptors approved for renal cell carcinoma and gastrointestinal stromal tumour that has also been studied for AML in several clinical trials. However, the precise mechanism of sunitinib action against AML remains unclear and requires further investigation. For this purpose, this study was conducted using human AML cell lines (HL60 and KG-1) and AML patients' mononucleated cells. Sunitinib induced G1 phase arrest associated with decreased cyclin D1, cyclin D3, and cyclin-dependent kinase (Cdk)2 and increased p27(Kip1), pRb1, and p130/Rb2 expression and phosphorylated activation of protein kinase C alpha and beta (PKCα/ß). Selective PKCα/ß inhibitor treatment abolished sunitinib-elicited AML differentiation, suggesting that PKCα/ß may underlie sunitinib-induced monocytic differentiation. Furthermore, sunitinib increased pro-apoptotic molecule expression (Bax, Bak, PUMA, Fas, FasL, DR4, and DR5) and decreased anti-apoptotic molecule expression (Bcl-2 and Mcl-1), resulting in caspase-2, caspase-3, caspase-8, and caspase-9 activation and both death receptor and mitochondria-dependent apoptosis. Taken together, these findings provide evidence that sunitinib targets AML cells through both differentiation and apoptosis pathways. More clinical studies are urgently needed to demonstrate its optimal clinical applications in AML.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Indóis/farmacologia , Indóis/uso terapêutico , Leucemia Mieloide Aguda , Pirróis/farmacologia , Pirróis/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Células HL-60 , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Sunitinibe , Resultado do Tratamento , Células Tumorais Cultivadas
13.
Methods ; 56(2): 223-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22062957

RESUMO

Due to its physiologic role in modulating adhesive interactions between blood cells and the endothelium during inflammatory processes or at injury sites, the adhesion molecule P-selectin is of great interest. The level of soluble P-selectin in plasma or serum can be detected and used as a clinical predictor for adverse cardiovascular events, leading to the presumption that it is secreted, shed or cleaved from the cell membrane during the process of diseases. Increased levels of soluble P-selectin in the plasma have been shown to be associated with a range of cardiovascular disorders, including coronary artery disease, hypertension and atrial fibrillation. Therefore, it is of huge significance to develop simple, rapid and sensitive methods for the detection of such pathological predictors, not only for facilitating the surveillance of cardiovascular mortality/sudden cardiac death, but also for effectively monitoring the drug potency on platelets based on measurement of P-selectin performed on fixed blood samples following platelet stimulation in whole blood in a remote setting. We herein developed a simple, yet novel and sensitive electrochemical sandwich immunosensor for the detection of P-selectin; it operates through covalent linkage of anti-P-selectin antibody on CNT@GNB nanocomposites-modified disposable screen-printed electrode as the detection platform, with the potassium ferrocyanide-encapsulated, anti-P-selectin-tagged liposomal biolabels as the electrochemical signal probes. The immunorecognition of the sample P-selectin by the liposomal biolabels occurred on the surface of the electrodes; the release of potassium ferrocyanide from the bound liposomal biolabels extensively contributed to the increase in electrochemical signal, which was acquired in HCl solution at +0.32V in square wave voltammetry mode. The resulting sigmoidally shaped dose-response curves possessed a linear dynamic working range from 1×10(-13) to 1×10(-5)g/mL. This liposome-based electrochemical immunoassay provides an amplification approach for detecting P-selectin at trace levels, leading to a detection limit as low as 4.3fg (equivalent to 5µL of 0.85pg/mL solution). A commercially available ELISA kit was used as a reference method to validate the newly-developed assay through the analysis of mouse serum samples. A strong correlation was observed between the two data sets as the R-squared value of 0.997 from the linear regression line. This electrochemical immunosensor will be useful for the detection of P-selectin in biological fluids and tissue extracts.


Assuntos
Técnicas Biossensoriais/instrumentação , Doenças Cardiovasculares/diagnóstico , Imunoensaio/instrumentação , Selectina-P/sangue , Animais , Biomarcadores/sangue , Biomarcadores/química , Técnicas Biossensoriais/métodos , Doenças Cardiovasculares/imunologia , Membrana Celular/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ensaio de Imunoadsorção Enzimática , Ferrocianetos/química , Ácido Clorídrico/química , Imunoensaio/métodos , Limite de Detecção , Modelos Lineares , Lipossomos/química , Camundongos , Nanocompostos/química , Reprodutibilidade dos Testes , Fatores de Risco , Solubilidade , Fatores de Tempo
14.
Int J Mol Sci ; 14(9): 19186-201, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-24051402

RESUMO

Essential oils extracted from aromatic plants exhibit important biological activities and have become increasingly important for the development of aromatherapy for complementary and alternative medicine. The essential oil extracted from Cinnamomum cassia Presl (CC-EO) has various functional properties; however, little information is available regarding its anti-tyrosinase and anti-melanogenic activities. In this study, 16 compounds in the CC-EO have been identified; the major components of this oil are cis-2-methoxycinnamic acid (43.06%) and cinnamaldehyde (42.37%). CC-EO and cinnamaldehyde exhibited anti-tyrosinase activities; however, cis-2-methoxycinnamic acid did not demonstrate tyrosinase inhibitory activity. In murine B16 melanoma cells stimulated with α-melanocyte-stimulating hormone (α-MSH), CC-EO and cinnamaldehyde not only reduced the melanin content and tyrosinase activity of the cells but also down-regulated tyrosinase expression without exhibiting cytotoxicity. Moreover, CC-EO and cinnamaldehyde decreased thiobarbituric acid-reactive substance (TBARS) levels and restored glutathione (GSH) and catalase activity in the α-MSH-stimulated B16 cells. These results demonstrate that CC-EO and its major component, cinnamaldehyde, possess potent anti-tyrosinase and anti-melanogenic activities that are coupled with antioxidant properties. Therefore, CC-EO may be a good source of skin-whitening agents and may have potential as an antioxidant in the future development of complementary and alternative medicine-based aromatherapy.


Assuntos
Cinnamomum aromaticum/metabolismo , Regulação para Baixo/efeitos dos fármacos , Melaninas/metabolismo , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Acroleína/análogos & derivados , Acroleína/farmacologia , Animais , Catalase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cinnamomum aromaticum/química , Glutationa/metabolismo , Melaninas/antagonistas & inibidores , Hormônios Estimuladores de Melanócitos/farmacologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Óleos Voláteis/química , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
J Food Drug Anal ; 31(4): 664-682, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38526823

RESUMO

Dietary factors and chronic hyperglycemia are linked to the formation of advanced glycation end products (AGEs) and prostate cancer (PCa) risk. The activation of the receptor for AGEs (RAGE) acts as a bridge between various RAGE ligands and certain malignancies. This study showed that the interaction of AGEs and RAGE promoted PCa cell proliferation, invasion, and autophagy-mediated survival in response to chemotherapeutic agents. RAGE-overexpressed PCa cells underwent epithelial-mesenchymal transition and showed increased cancer stem cell-like properties. In mouse xenograft models, RAGE-overexpressed cells showed more substantial tumorigenic capacity than parental cells, whereas RAGE knockdown decreased tumorigenicity. The clinical data validated a positive correlation between high AGE and RAGE expressions with poor clinical outcomes. Our findings suggest that the AGE-RAGE axis facilitates PCa progression and aggressiveness. Prostatic AGEs and RAGE expression levels are associated with PCa prognosis. Adherence to a reduced-AGE diet and targeting RAGE are potential approaches to complement and synergize with the current PCa therapies.


Assuntos
Relevância Clínica , Neoplasias da Próstata , Masculino , Humanos , Camundongos , Animais , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Prognóstico , Modelos Animais de Doenças
16.
Artigo em Inglês | MEDLINE | ID: mdl-23304206

RESUMO

Retinoic acid (RA) has been believed to be an anticancer drug for a long history. However, the molecular mechanisms of RA actions on cancer cells remain diverse. In this study, the dose-dependent inhibition of RA on DU145 cell proliferation was identified. Interestingly, RA treatment triggered p35 cleavage (p25 formation) and Cdk5 overactivation, and all could be blocked by Calpain inhibitor, Calpeptin (CP). Subsequently, RA-triggered DU145 apoptosis detected by sub-G1 phase accumulation and Annexin V staining could also be blocked by CP treatment. Furthermore, RA-triggered caspase 3 activation and following Cdk5 over-activation were destroyed by treatments of both CP and Cdk5 knockdown. In conclusion, we report a new mechanism in which RA could cause apoptosis of androgen-independent prostate cancer cells through p35 cleavage and Cdk5 over-activation. This finding may contribute to constructing a clearer image of RA function and bring RA as a valuable chemoprevention agent for prostate cancer patients.

17.
Artigo em Inglês | MEDLINE | ID: mdl-22811744

RESUMO

The incidence of cirrhosis is rising due to the widespread occurrence of chronic hepatitis, as well as the evident lack of an established therapy for hepatic fibrosis. In the search for hepatoprotective therapeutic agents, Graptopetalum paraguayense (GP) showed greater cytotoxicity toward hepatic stellate cells than other tested herbal medicines. Histopathological and biochemical analyses suggest that GP treatment significantly prevented DMN-induced hepatic inflammation and fibrosis in rats. Microarray profiling indicated that expression of most of metabolism- and cell growth and/or maintenance-related genes recovered to near normal levels following GP treatment as classified by gene ontology and LSM analysis, was observed. ANOVA showed that expression of 64% of 256 liver damage-related genes recovered significantly after GP treatment. By examining rat liver samples with Q-RT-PCR, five liver damage-related genes were identified. Among them, Egr1 and Nrg1 may serve as necroinflammatory markers, and Btg2 may serve as a fibrosis marker. Oldr1 and Hmgcs1 were up- and down-regulated markers, respectively. A publicly accessible website has been established to provide access to these data Identification of 44 necroinflammation-related and 62 fibrosis-related genes provides useful insight into the molecular mechanisms underlying liver damage and provides potential targets for the rational development of therapeutic drugs such as GP.

18.
BMC Genomics ; 12 Suppl 3: S23, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22369086

RESUMO

BACKGROUND: Cardiovascular disease is the chief cause of death in Taiwan and many countries, of which myocardial infarction (MI) is the most serious condition. Hyperlipidemia appears to be a significant cause of myocardial infarction, because it causes atherosclerosis directly. In recent years, copy number variation (CNV) has been analyzed in genomewide association studies of complex diseases. In this study, CNV was analyzed in blood samples and SNP arrays from 31 myocardial infarction patients with hyperlipidemia. RESULTS: We identified seven CNV regions that were associated significantly with hyperlipidemia and myocardial infarction in our patients through multistage analysis (P<0.001), at 1p21.3, 1q31.2 (CDC73), 1q42.2 (DISC1), 3p21.31 (CDCP1), 10q11.21 (RET) 12p12.3 (PIK3C2G) and 16q23.3 (CDH13), respectively. In particular, the CNV region at 10q11.21 was examined by quantitative real-time PCR, the results of which were consistent with microarray findings. CONCLUSIONS: Our preliminary results constitute an alternative method of evaluating the relationship between CNV regions and cardiovascular disease. These susceptibility CNV regions may be used as biomarkers for early-stage diagnosis of hyperlipidemia and myocardial infarction, rendering them valuable for further research and discussion.


Assuntos
Variações do Número de Cópias de DNA , Hiperlipidemias/complicações , Hiperlipidemias/genética , Infarto do Miocárdio/complicações , Infarto do Miocárdio/genética , Adulto , Idoso , Colesterol/sangue , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem
19.
Biochem Biophys Res Commun ; 405(2): 168-72, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21216229

RESUMO

Mutations of the p53 tumor suppressor gene are the most common mutations found in human tumors. There is increasing evidence that suggests that p53 status is a determinant of chemosensitivity of tumor cells. We have previously demonstrated that p53 is a crucial regulator in mediating gefitinib-induced cell death, which upregulates apoptosis-related molecules. However, the mechanism of p53 involvement in cellular resistance to gefitinib remains unclear. In this study, we found that human non-small cell lung cancer cells, A549, with wild-type p53 exhibited a low level of Aurora-A expression and were sensitive to treatment with gefitinib. p53-knockdown A549 cells exhibited a high level of Aurora-A expression and were resistant to gefitinib-mediated apoptosis induction. In addition, the silencing of Aurora-A expression using an Aurora-A specific siRNA in p53-knockdown cells sensitized the A549 cancer cells to gefitinib-mediated apoptosis, suggesting a role for Aurora-A in gefitinib resistance. The activation of Aurora-A was accompanied by destabilization of IκBα and an increase in NF-κB transcriptional activity and was correlated with gefitinib resistance. Conversely, knockdown of Aurora-A with a siRNA stabilized IκB protein suppressed NF-κB activation and reduced gefitinib resistance. Additionally, ectopic expression of an active form of Aurora-A increased the degradation of IκB, the activation of NF-κB and the enhancement of gefitinib resistance in comparison with parental cells. These results suggest that Aurora-A is potentially involved in promoting gefitinib resistance via the activation of NF-κB pathway. Our findings also suggest that p53 not only stimulates apoptosis-related event but also inhibits the drug-resistance ability of Aurora-A, and consequently promotes the gefitinib-induced cellular apoptotic process.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/enzimologia , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Quinazolinas/farmacologia , Transporte Ativo do Núcleo Celular , Aurora Quinases , Linhagem Celular Tumoral , Gefitinibe , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Neoplasias Pulmonares/genética , Mutação , Inibidor de NF-kappaB alfa , NF-kappa B/genética , Ativação Transcricional , Proteína Supressora de Tumor p53/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-21760824

RESUMO

Calocedrus formosana (Florin) bark acetone/ethylacetate extracts are known to exert an antitumor effect on some human cancer cell lines, but the mechanism is yet to be defined. The aim of this study was to determine the effects of Florin leaf methanol extracts on the growth and apoptosis of human bladder cancer cell lines. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that the growth of these bladder cancer cells was potently inhibited by the Florin leaf extracts. The cell cycle of these extract-treated cells (TCCSUP cells) was arrested at the G2/M phase as determined by flow cytometry. Western blot analysis revealed the increases of cyclin B1 and Cdc2 kinase levels, alone with the decrease of phosphorylated Cdc2 kinase, after treating these cells with the extracts. An immunofluorescence assessment of ß-tubulin showed decreased levels of polymerized tubulin in treated cells. However, the proteolytic cleavage of poly ADP-ribose polymerase and the activation of caspase-3/-8/-9 were all increased upon treatments of extracts. The concurrent increase of Bax and decrease of Bcl-2 levels indicated that the extracts could induce apoptosis in these treated cells. Taken together, these results suggest that the Florin leaf extracts may be an effective antibladder cancer agent.

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