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2.
Cancer Control ; 22(2): 177-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26068762

RESUMO

BACKGROUND: Patients with Barrett esophagus (BE) are predisposed to developing dysplasia and cancer. Adenocarcinoma, which is associated with BE, is the most common type of esophageal tumor and, typically, it has an aggressive clinical course and a high rate of mortality. METHODS: The English-language literature relating to tumor epidemiology, etiology, and the pathogenesis of BE was reviewed and summarized. RESULTS: The role of pathologists in the diagnosis and pitfalls associated with grading Barrett dysplasia is addressed. Current molecular testing for Barrett neoplasia, as well as testing methods currently in development, is discussed, focusing on relevant tests for diagnosing tumor types, determining prognosis, and assessing therapeutic response. CONCLUSIONS: Grading is essential for developing appropriate treatment plans, follow-up visits, and therapeutic interventions for each patient. Familiarity with current molecular testing methods will help physicians correctly diagnose the disease and select the most appropriate therapy for each of their patients.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Adenocarcinoma/genética , Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Genes erbB-2 , Genes p53 , Humanos , Hibridização in Situ Fluorescente , Mucosa Intestinal/patologia , Gradação de Tumores , Análise de Sequência com Séries de Oligonucleotídeos , Lesões Pré-Cancerosas , Prognóstico , Fatores de Risco
3.
Mol Cancer Ther ; 14(7): 1570-81, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25934708

RESUMO

Pancreatic cancer is an aggressive and deadly malignancy responsible for the death of over 37,000 Americans each year. Gemcitabine-based therapy is the standard treatment for pancreatic cancer but has limited efficacy due to chemoresistance. In this study, we evaluated the in vitro and in vivo effects of gemcitabine combined with the selective nuclear export (CRM1) inhibitor KPT-330 on pancreatic cancer growth. Human pancreatic cancer MiaPaCa-2 and metastatic pancreatic cancer L3.6pl cell lines were treated with different concentrations of KPT-330 and gemcitabine alone or in combination, and anchorage-dependent/independent growth was recorded. In addition, L3.6pl cells with luciferase were injected orthotopically into the pancreas of athymic nude mice, which were treated with (i) vehicle (PBS 1 mL/kg i.p., 2/week and povidone/pluronic F68 1 mL/kg p.o., 3/week), (ii) KPT-330 (20 mg/kg p.o., 3/week), (iii) gemcitabine (100 mg/kg i.p., 2/week), or (iv) KPT-330 (10 mg/kg) + gemcitabine (50 mg/kg) for 4 weeks. KPT-330 and gemcitabine alone dose-dependently inhibited anchorage-dependent growth in vitro and tumor volume in vivo compared with vehicle treatment. However, the combination inhibited growth synergistically. In combination, KPT-330 and gemcitabine acted synergistically to enhance pancreatic cancer cell death greater than each single-agent therapy. Mechanistically, KPT-330 and gemcitabine promoted apoptosis, induced p27, depleted survivin, and inhibited accumulation of DNA repair proteins. Together, our data suggest that KPT-330 potentiates the antitumor activity of gemcitabine in human pancreatic cancer through inhibition of tumor growth, depletion of the antiapoptotic proteins, and induction of apoptosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/farmacologia , Camundongos Nus , Microscopia Confocal , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Triazóis/administração & dosagem , Triazóis/farmacologia , Carga Tumoral/efeitos dos fármacos , Gencitabina
4.
Cardiovasc Toxicol ; 11(4): 325-33, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21744298

RESUMO

Obesity-induced remodeling of cardiac extracellular matrix (ECM) leads to myocardial fibrosis and ultimately diastolic dysfunction. Leptin, an adipocyte hormone, is emerging as a novel mechanistic link between obesity and heart diseases. Despite the known essential role of leptin in hepatic and renal fibrosis, the in vivo effects of leptin on cardiac ECM remodeling remain unclear. Our objective was to define the role of leptin as a key mediator of pro-fibrogenic responses in the heart. In vitro administration of leptin to primary cardiofibroblasts resulted in significant stimulation of pro-collagen Iα ( 1 ) and a decrease in pro-matrix metalloproteinase (MMP)-8, -9 and -13 gene expressions at 24 h. To study the in vivo pro-fibrotic effect, leptin was administrated to C57BL/6 and leptin-deficient ob/ob mice for 8 weeks. With exogenous leptin ob/ob mice displayed passive diastolic filling dysfunction, coincided with significant increase in myocardial collagen compared with ob/ob controls. We also observed a marked stimulation of pro-collagen IIIα ( 1 ) and suppression of pro-MMP-8, TIMP-1 and -3 gene expressions in leptin-treated ob/ob mice. Our findings suggest pro-fibrotic effects of leptin in the heart, primarily through the predominance of collagen synthesis over degradation.


Assuntos
Matriz Extracelular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Leptina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Ecocardiografia , Matriz Extracelular/metabolismo , Feminino , Fibroblastos/metabolismo , Fibrose/induzido quimicamente , Fibrose/metabolismo , Fibrose/patologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Leptina/deficiência , Metaloproteinases da Matriz Secretadas/genética , Metaloproteinases da Matriz Secretadas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Obesidade/metabolismo , RNA Mensageiro/metabolismo , Inibidores Teciduais de Metaloproteinases/genética , Inibidores Teciduais de Metaloproteinases/metabolismo
5.
Cardiovasc Toxicol ; 10(3): 190-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20556665

RESUMO

Left ventricular diastolic dysfunction is an important predictor of prognosis and mortality of heart failure. Increased left ventricular stiffness can be associated with excessive myocardial fibrosis and increased cross-linked collagen by the enzyme lysyl oxidase (LOX). These cardiac extracellular matrix (ECM) remodeling processes are affected by T-lymphocyte function and phenotype. We sought to examine the role of T lymphocytes in myocardial LOX regulation in diet-induced fibrotic hearts. Female SCID mice, devoid of functional T lymphocytes, and wild-type (WT) C57BL/6 were treated with a high-fat high-simple carbohydrate (HFHSC) diet for 12 months. HFHSC-fed WT mice demonstrated a significant increase in the catalytic activity of myocardial LOX compared with respective controls. These changes coincided with a marked increase in ECM collagen cross-linking and impaired diastolic filling pattern. However, induction of LOX was minimal in the SCID mice compared with the WT group. Correspondingly fibrillar cross-linked collagen concentrations and diastolic dysfunction were less prominent in the SCID mice compared with the WT group. Our results suggest a role for T lymphocytes in this dietary induction of diastolic dysfunction through modulation of LOX-dependent collagen maturation.


Assuntos
Dieta/efeitos adversos , Cardiopatias/enzimologia , Cardiopatias/etiologia , Proteína-Lisina 6-Oxidase/metabolismo , Linfócitos T/fisiologia , Animais , Western Blotting , Colágeno/metabolismo , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/ultraestrutura , Feminino , Fibrose , Expressão Gênica/efeitos dos fármacos , Cardiopatias/patologia , Hemodinâmica/fisiologia , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , RNA/biossíntese , RNA/genética , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Am J Physiol Heart Circ Physiol ; 297(3): H976-82, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19592613

RESUMO

Metabolic syndrome (MetS) represents an increased risk of cardiovascular disease. Although its individual components adversely affect cardiac structure and function, the extent to which multiple components of MetS affect the cardiac extracellular matrix (ECM) has not been well characterized. Lysyl oxidase (LOX) is one of the cardiac ECM-modifying enzymes that catalyze the formation of collagen cross-linking. Our objective was to define the effect of diet-induced MetS on the LOX enzyme. MetS was induced in male C57BL/6 mice by administrating a high-fat, high-simple carbohydrate diet for 6 mo. Gene expression was determined by real-time PCR. The cardiac protein expression and enzymatic activity of LOX were measured. The severity of fibrosis was assessed by histology and hydroxylproline assay. Cardiac diastolic function was assessed by in vivo analysis of the pressure-volume relationship. LOX, matrix metalloproteinases, and their tissue inhibitors were analyzed, and of these three, LOX was most significantly changed in the MetS mice. Despite the blunted gene expression of LOX isoforms, MetS mice demonstrated a significant upregulation of bone morphogenetic protein-1. Correspondingly, there was an increase in the ratio of protein expression of mature to proenzyme LOX by 25.9%, enhanced LOX activity by 50.0%, and increased cardiac cross-linked collagen compared with the controls. This fibrotic response coincided with a marked increase in end-diastolic pressure, increased left ventricular stiffness, and impaired diastolic filling pattern. Our data signify that diet-induced MetS alters the remodeling enzymes, mainly LOX, thereby altering ECM structure by increasing the amount of cross-linking and inducing diastolic dysfunction.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Síndrome Metabólica/metabolismo , Miocárdio/enzimologia , Proteína-Lisina 6-Oxidase/metabolismo , Remodelação Ventricular/fisiologia , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Animais , Pressão Sanguínea , Colágeno/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Proteínas da Matriz Extracelular/genética , Fibrose , Regulação Enzimológica da Expressão Gênica , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Proteína-Lisina 6-Oxidase/genética , Volume Sistólico , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/patologia
7.
Nutr Res ; 28(3): 166-71, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19083404

RESUMO

Asthma, affecting as many as 400 million individuals worldwide, is one of the most prevalent chronic health condition in the United States. With an increasing number of patients with asthma and the frequent inability of conventional lifestyle modification and therapy to effectively control the problem, nutritional and dietary therapies are being sought. This study was undertaken to investigate the efficacy of the purple passion fruit peel (PFP) extract, a novel mixture of bioflavonoids, on asthma symptoms. Patients with asthma were studied in a 4-week randomized, placebo-controlled, double-blind trial with oral administration of PFP extract (150 mg/d) or placebo pills. The effects of PFP extract were evaluated by assessing the clinical symptoms of asthma and spirometry tests. Most clinical symptoms of asthma of the PFP extract-treated group were moderated significantly compared to the baseline. The prevalence of wheeze, cough, as well as shortness of breath was reduced significantly in group treated with PFP extract (P < .05), whereas the placebo caused no significant improvement. Purple passion fruit peel extract supplementation resulted in a marked increase in forced vital capacity (P < .05) as placebo showed no effect. However, no significant improvement was observed in the forced expiratory volume at 1 second of those supplemented with PFP extract. No adverse effect was reported by any of study participants. The PFP extract may be safely offered to asthmatic subjects as an alternative treatment option to reduce clinical symptoms.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Flavonoides/uso terapêutico , Passiflora/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Administração Oral , Adolescente , Adulto , Antiasmáticos/efeitos adversos , Tosse/tratamento farmacológico , Tosse/epidemiologia , Método Duplo-Cego , Dispneia/tratamento farmacológico , Dispneia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/efeitos adversos , Prevalência , Sons Respiratórios/efeitos dos fármacos , Índice de Gravidade de Doença , Espirometria , Resultado do Tratamento , Capacidade Vital/efeitos dos fármacos , Adulto Jovem
8.
Nutr Res ; 28(5): 315-20, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-19083426

RESUMO

Patients with type 2 diabetes are at considerable risk of excessive morbidity and mortality from cardiovascular disease (CVD). We investigated the clinical effectiveness of Pycnogenol, a flavonoid-rich dietary supplement, in reducing antihypertensive medication use and CVD risk factors in subjects with type 2 diabetes. Forty-eight individuals were enrolled in a randomized, double-blind, placebo-controlled trial with parallel-group design. Patients were diagnosed with both type 2 diabetes and mild to moderate hypertension and were undergoing treatment with angiotensin-converting enzyme (ACE) inhibitors. Subjects were randomly assigned to receive either Pycnogenol pill (125 mg daily) or matched placebo for 12 weeks. According to the values of blood pressure (BP) measured at 2-week intervals, the pretrial ACE inhibitor dosage was left unchanged, reduced by 50%, or brought back to the pretrial dosage until a stable BP was obtained. Fasting plasma glucose, low-density lipoprotein (LDL) cholesterol, glycosylated hemoglobin (HbA1c), serum endothelin-1, and urinary albumin were evaluated monthly. Pycnogenol treatment achieved BP control in 58.3% of subjects at the end of the 12 weeks with 50% reduction in individual pretrial dose of ACE-inhibitors (P <.05). Plasma endothelin-1 decreased by 3.9 pg/mL in Pycnogenol-treated group vs 0.5 pg/mL increase in control group (P < .001). Mean HbA1c dropped by 0.8% in Pycnogenol-treated group (P < .05), whereas it decreased by 0.1% in control group. Fasting plasma glucose declined by 23.7 mg/dL in Pycnogenol-treated group vs 5.7 mg/dL in control group (P < .0001). Low-density lipoprotein cholesterol improved significantly in Pycnogenol-treated group, declining by 12.7 mg/dL (P < .001). A significant decrease in urinary albumin level was observed at week 8 compared with the control group (P < .05). However, this reduction was not significant at 12th week. After 12 weeks of supplementation, Pycnogenol resulted in improved diabetes control, lowered CVD risk factors, and reduced antihypertensive medicine use vs controls.


Assuntos
Antioxidantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Flavonoides/uso terapêutico , Hipertensão/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Fitoterapia , Pinus , Idoso , Albuminas/análise , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Glicemia/análise , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/complicações , Método Duplo-Cego , Endotelina-1/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Casca de Planta , Extratos Vegetais/uso terapêutico
9.
Cardiovasc Toxicol ; 7(1): 10-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17646678

RESUMO

Cardiac remodeling is a determinant of the clinical progression of heart failure and now slowing or reversing remodeling is considered as a potential therapeutic target in heart failure. Pycnogenol has been reported to mediate a number of beneficial effects in the cardiovascular system but its effects on hemodynamic and functional cardiovascular changes following cardiac remodeling have not been elucidated. Therefore, we investigated the influence of Pycnogenol supplementation (30 mg/kg) on left ventricular function and myocardial extracellular matrix composition in old C57BL/6N mice following induction of cardiac remodeling by chronic nitric oxide synthase blockade by NG-nitro-L-arginine methyl ester (L-NAME) administration. L-NAME-treated mice demonstrated dilated cardiomyopathy at compensated state, associated with a significant increase of pro-matrix metalloproteinase (MMP)-9 gene expression and activity, a marked decrease in pro-collagen IIIalpha1 gene expression, and a subsequent reduction in cardiac total and cross-linked collagen content. Upon supplementation with Pycnogenol in L-NAME-exposed mice, cardiac gene expression patterns for pro-MMP-2, -9, and -13, and MMP-9 activity were significantly decreased, associated with a significant increase in cardiac tissue inhibitor of metalloproteinase (TIMP)-4 expression. These findings were coincided with a marked increase in myocardial total and cross-linked collagen content, compared with L-NAME-only-treated mice. Moreover, Pycnogenol treatment was associated with reversal of L-NAME-induced alternations in hemodynamic parameters. These data indicate that Pycnogenol can prevent adverse myocardial remodeling induced by L-NAME, through modulating TIMP and MMPs gene expression, MMPs activity, and further reduction in myocardial collagen degradation rate.


Assuntos
Envelhecimento/fisiologia , Inibidores Enzimáticos/toxicidade , Matriz Extracelular/efeitos dos fármacos , Flavonoides/farmacologia , Coração/efeitos dos fármacos , NG-Nitroarginina Metil Éster/toxicidade , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Remodelação Ventricular/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Colágeno/metabolismo , Reagentes de Ligações Cruzadas , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/citologia , Extratos Vegetais , RNA/biossíntese , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
J Nutr Biochem ; 16(2): 85-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15681166

RESUMO

Immunosenescence via increased inflammatory cytokines may play key regulatory roles in facilitating cardiac infections and heart failure. Based upon recent evidence, we hypothesize that cytokine polarization due to aging directly dysregulates fibroblasts, leading to altered cardiac structure and dysfunction. Some dietary fatty acids should ameliorate heightened inflammatory cytokines thereby retarding cardiac pathology, loss of structural collagen and premature death from heart failure. For example, T-helper (Th) 2 cells' cytokine levels are very high in seniors who have increased heart disease due to suppressed resistance to cardiotrophic pathogens. In addition, such inflammatory cytokines deregulate fibroblasts, thus reducing collagen synthesis, weakening muscle structure and heart pump function for heart failure and hypertension. Therefore, supplementation with n-3 polyunsaturated fatty (PUFA) or conjugated linoleic acids, by reducing Th2 and increasing Th1 cytokines, may provide a sensible and widely available means to treat and even prevent excessive inflammatory cytokines and their cardiotoxic effects. On the other hand, dietary n-6 PUFA may promote cytokine polarization in seniors, exacerbating age-related heart dysfunction.


Assuntos
Envelhecimento/fisiologia , Cardiopatias/imunologia , Imunidade/fisiologia , Fenômenos Fisiológicos da Nutrição , Animais , Citocinas/fisiologia , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Linoleicos Conjugados/administração & dosagem , Camundongos , Células Th1/imunologia , Células Th2/imunologia
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