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1.
Eur Rev Med Pharmacol Sci ; 24(8): 4172-4179, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32373953

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is one of the most common fatal cancer in the world and androgens are among the possible etiological factors. Congenital adrenal hyperplasia (CAH) is a group of inherited diseases caused by enzyme failure in the steroid biosynthesis of the adrenal cortex, resulting in an augmented 17-hydroxyprogesterone, androstenedione and testosterone production. While the occurrence of testicular adrenal rest tumors and adrenocortical tumors in congenital adrenal hyperplasia is well described in the literature, no data on HCC occurrence are available. CASE PRESENTATION: A 35-years-old Italian man of Caucasian origin, affected by non-classic CAH due to partial 21-hydroxylase deficiency came to observation for revaluation of his adrenal picture. Besides common hormonal and biochemical analysis, an abdomen Magnetic Resonance Imaging was performed, resulting in an 18 mm large nodular lesion between liver segments VII and VIII. Radiological reports matched with an increased serum α-fetoprotein level. A surgical removal of the lesion was performed. After that, several recurrences of the lesion, which was consequently treated by radiofrequency ablation, occurred. Every recurrence was accompanied by an increase in testosterone and steroid hormone binding globulin serum levels. CONCLUSIONS: Our report suggests the need for screening of liver lesions in males affected by this syndrome.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Recidiva Local de Neoplasia/sangue , Hiperplasia Suprarrenal Congênita/metabolismo , Hiperplasia Suprarrenal Congênita/cirurgia , Adulto , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirurgia , Masculino , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
2.
Phys Med ; 54: 42-48, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30337009

RESUMO

Interventional cardiac procedures may be associated with high patient doses and therefore require special attention to protect the patients from radiation injuries such as skin erythema, cardiovascular tissue reactions or radiation-induced cancer. In this study, patient exposure data is collected from 13 countries (37 clinics and nearly 50 interventional rooms) and for 10 different procedures. Dose data was collected from a total of 14,922 interventional cardiology procedures. Based on these data European diagnostic reference levels (DRL) for air kerma-area product are suggested for coronary angiography (CA, DRL = 35 Gy cm2), percutaneous coronary intervention (PCI, 85 Gy cm2), transcatheter aortic valve implantation (TAVI, 130 Gy cm2), electrophysiological procedures (12 Gy cm2) and pacemaker implantations. Pacemaker implantations were further divided into single-chamber (2.5 Gy cm2) and dual chamber (3.5 Gy cm2) procedures and implantations of cardiac resynchronization therapy pacemaker (18 Gy cm2). Results show that relatively new techniques such as TAVI and treatment of chronic total occlusion (CTO) often produce relatively high doses, and thus emphasises the need for use of an optimization tool such as DRL to assist in reducing patient exposure. The generic DRL presented here facilitate comparison of patient exposure in interventional cardiology.


Assuntos
Cardiologia/normas , Europa (Continente) , Valores de Referência
3.
Phys Med ; 32(2): 393-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26781588

RESUMO

PURPOSE: In the setting of thorax Computed Tomography (CT), the main purpose of this work is to quantify differences in Size-Specific Dose Estimate (SSDE), calculated on the basis of both effective diameter and water-equivalent diameter, accounting for patient size and tissue attenuation, respectively. MATERIALS AND METHODS: An in-house software was developed to measure water-equivalent diameter and effective diameter on each CT slice, for 133 CT examinations. SSDE was calculated according to the Report of American Association of Physicists in Medicine Task Group (AAPM TG) 204 and 220. The ratio between effective and water-equivalent diameters was studied as function of cross-sectional air-to-body area ratio, for the slice located in the middle of the scan range. RESULTS: When AAPM TG 220 prescriptions were applied, SSDE was mostly found larger than that obtained with AAPM TG 204 recommendations. On average, a difference of about 12% was observed, in spite of a considerable variability (from -18% to 53%). The ratio between effective and water-equivalent diameters ranged from 0.97 to 1.31, with a mean value of 1.15. Moreover, it was found considerably correlated with cross-sectional air-to-body ratio (Pearson's coefficient was 0.78 for women, 0.90 for men). CONCLUSION: The discrepancy obtained by calculating SSDE on the basis of AAPM TG 204, instead of AAPM TG 220 Report, may vary substantially. Fluctuations were justified by the variability observed in the relative amount of low attenuating tissues in body, which was proved to be considerably correlated to the ratio between effective and water-equivalent diameters.


Assuntos
Doses de Radiação , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Água , Feminino , Humanos , Masculino , Imagens de Fantasmas , Estudos Retrospectivos , Software
4.
Abdom Imaging ; 38(4): 736-44, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22986351

RESUMO

PURPOSE: We evaluated whether the addition of delayed phase imaging (DPI) gadobenate dimeglumine-enhanced MRI to dynamic postcontrast imaging improves the characterization of small hepatocellular carcinoma (HCC) and the differentiation between HCC, high grade dysplastic nodules (HGDN), and low grade dysplastic nodules (LGDN). METHODS: Twenty-five cirrhotic patients with 30 nodules (16 HCC, 8 HGDNs, and 6 LGDNs; maximum size of 3 cm) were included in this retrospective study. The diagnostic reference standard was histology. All the patients underwent MRI both prior to and following intravenous administration of gadobenate dimeglumine. The lesions were classified as hypointense, isointense, hyperintense on DPI for qualitative assessment. In the quantitative analysis the relative tumor-liver contrast to noise ratio (CNR) of the lesions on DPI was calculated. RESULTS: All HCCs were hypointense on DPI while only 8 (57.1%) of 14 DNs were hypointense and only 1 of 6 (16.6%) LGDNs was hypointense. There was a statistically significant difference in the hypointensity on DPI between HCCs and DNs (p = 0.003) in the qualitative analysis but not in the CNR values while there was a strong statistically significant difference in the hypointensity on DPI in the qualitative (p = 0.00001) and quantitative analysis (p < 0.05) between LGDNs and the group obtained by unifying HGDNs and HCCs. CONCLUSION: DPI is helpful in differentiating HCCs and HGDNs from LGDNs. Demonstration of hypointensity on DPI should raise the suspicion of HGDN or hypovascular HCC in the case of nodules with atypical dynamic pattern.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Biópsia com Agulha de Grande Calibre , Carcinoma Hepatocelular/patologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Masculino , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos
6.
Br J Pharmacol ; 162(5): 1186-201, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21091650

RESUMO

BACKGROUND AND PURPOSE: Pancreatitis represents a life-threatening inflammatory condition where leucocytes, cytokines and vascular endothelium contribute to the development of the inflammatory disease. The glucocorticoid-induced tumour necrosis factor (TNF) receptor family-related protein (GITR) is a costimulatory molecule for T lymphocytes, modulates innate and adaptive immune system and has been found to participate in a variety of immune responses and inflammatory processes. Our purpose was to verify whether inhibition of GITR triggering results in a better outcome in experimental pancreatitis. EXPERIMENTAL APPROACH: In male GITR knock-out (GITR(-/-)) and GITR(+/+) mice on Sv129 background, acute pancreatitis was induced after i.p. administration of cerulein. Other experimental groups of GITR(+/+) mice were also treated with different doses of Fc-GITR fusion protein (up to 6.25 µg·mouse⁻¹), given by implanted mini-osmotic pump. Clinical score and pro-inflammatory parameters were evaluated. KEY RESULTS: A less acute pancreatitis was found in GITR(-/-) mice than in GITR(+/+) mice, with marked differences in oedema, neutrophil infiltration, pancreatic dysfunction and injury. Co-treatment of GITR(+/+) mice with cerulein and Fc-GITR fusion protein (6.25 µg·mouse⁻¹) decreased the inflammatory response and tissue injury, compared with treatment with cerulein alone. Inhibition of GITR triggering was found to modulate activation of nuclear factor κB as well as the production of TNF-α, interleukin-1ß, inducible nitric oxide synthase, nitrotyrosine, poly-ADP-ribose, intercellular adhesion molecule-1 and P-selectin. CONCLUSIONS AND IMPLICATIONS: The GITR-GITR ligand system is crucial to the development of acute pancreatitis in mice. Our results also suggest that the Fc-GITR fusion protein could be useful in the treatment of acute pancreatitis.


Assuntos
Pancreatite/etiologia , Receptores de Fator de Crescimento Neural/fisiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Animais , Apoptose , Ceruletídeo/toxicidade , Edema/etiologia , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Proteínas I-kappa B/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/metabolismo , Ligantes , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Inibidor de NF-kappaB alfa , Infiltração de Neutrófilos , Óxido Nítrico Sintase Tipo II/metabolismo , Selectina-P/metabolismo , Pancreatite/patologia , Pancreatite/fisiopatologia , Pancreatite/prevenção & controle , Poli(ADP-Ribose) Polimerases/metabolismo , Receptores de Fator de Crescimento Neural/administração & dosagem , Receptores de Fator de Crescimento Neural/deficiência , Receptores de Fator de Crescimento Neural/genética , Receptores do Fator de Necrose Tumoral/administração & dosagem , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Linfócitos T/fisiologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
BMJ Case Rep ; 20102010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-22766574

RESUMO

The clinical and instrumental findings revealed a case of autoimmune polyendocrine syndrome (APS) type 3B+C in a 41-year-old Caucasian woman with unexplained refractory iron-deficiency anaemia secondary to autoimmune atrophic gastritis and a long-term history of two different autoimmune diseases-Hashimoto's disease and vitiligo. Indeed the occurrence in the same patient of three or more autoimmune diseases defines APS. The first classification of APS was suggested by Neufeld and Blizzard in 1980 and it included four main types of APS on the basis of clinical features. The only case of APS type 3B+C was described by Amerio et al in 2006.


Assuntos
Anemia Ferropriva/diagnóstico , Compostos Ferrosos/administração & dosagem , Poliendocrinopatias Autoimunes/diagnóstico , Adulto , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/imunologia , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Biópsia por Agulha , Endoscopia do Sistema Digestório/métodos , Feminino , Seguimentos , Gastrite Atrófica/complicações , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/imunologia , Doença de Hashimoto/complicações , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/imunologia , Humanos , Imuno-Histoquímica , Infusões Intravenosas , Poliendocrinopatias Autoimunes/diagnóstico por imagem , Poliendocrinopatias Autoimunes/patologia , Medição de Risco , Resultado do Tratamento , Ultrassonografia Doppler , Vitiligo/complicações , Vitiligo/diagnóstico , Vitiligo/imunologia
8.
Int J Clin Pract ; 62(7): 1108-12, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18194277

RESUMO

INTRODUCTION: Liver fibrosis (LB) assessment plays an important role in hepatology. A common characteristic of all chronic liver diseases is the occurrence and progression of fibrosis towards cirrhosis. Besides its plain interest for prognosis purposes, determining the fibrosis reveals the natural history of the disease and the risk factors associated with its progression to guide the antifibrotic action of different treatments. DISCUSSION: Today, in clinical practice there are three available methods for the evaluation of LB. Biopsy, which is still considered as the 'gold standard' method. Serological markers and their mathematical combination are suggested in the last years in alternative to LB. More recently, transient elastography (TE) was proposed. TE is a simple and noninvasive method for measuring liver stiffness. This technique is based on the progression speed of an elastic shear wave within the liver. CONCLUSIONS: Currently, there are just a few studies capable of evaluating the TE effectiveness in chronic liver diseases, mainly in patients infected with hepatitis C virus (HCV). Its application must also be studied in the monitoring of patients suffering from chronic HCV infection and subjected to a treatment that can modify their degree of liver fibrosis. The results of TE must be interpreted according to the clinical background of the specialist.


Assuntos
Hepatite C Crônica/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/virologia , Sensibilidade e Especificidade
9.
Dig Liver Dis ; 40(3): 206-15, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18054850

RESUMO

BACKGROUND AND AIM: Aim of this study was to compare contrast-enhanced ultrasound and multi-detector row computed tomography in detecting arterial hypervascularity in small cirrhotic nodules. PATIENTS AND METHODS: Sixty-two nodules (41 measuring 1.0-2.0 cm, 21 measuring 2.1-3.0 cm) found in 55 cirrhotic patients were examined with both methods. Lesions displaying arterial hypervascularity with washout in the portal/venous phase on both studies were considered hepatocellular carcinomas and treated; all other nodules were subjected to ultrasound-guided fine-needle biopsy. RESULTS: The larger nodules (2.1-3.0 cm) included 19 hepatocellular carcinomas (90%), 1 macroregenerative nodule type I and 1 macroregenerative nodule type II; 35 (87%) of the smaller nodules were hepatocellular carcinomas, 2 were macroregenerative nodules type I, 2 macroregenerative nodules type II and 2 hemangiomas. The two studies yielded concordant findings for 54 nodules (87%), including 46 hypervascular on both examinations and 8 that were consistently hypovascular. Two of the latter nodules were hepatocellular carcinomas. The other eight nodules displayed arterial hypervascularity on only one of the studies. Six of these (75%) were hepatocellular carcinomas, including five that were negative in the contrast-enhanced ultrasound study. CONCLUSION: Computed tomography and contrast-enhanced ultrasound show high agreement in the vascular classification of small nodules detected by ultrasound in cirrhotic livers, although the former technique was slightly more sensitive in the detection of arterial hypervascularization.


Assuntos
Cirrose Hepática/diagnóstico por imagem , Fígado/irrigação sanguínea , Neovascularização Patológica/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Ultrassonografia Doppler/métodos , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Carcinoma Hepatocelular/diagnóstico , Diagnóstico Diferencial , Feminino , Seguimentos , Hemangioma/diagnóstico , Humanos , Injeções Intravenosas , Fígado/diagnóstico por imagem , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Fosfolipídeos/administração & dosagem , Estudos Prospectivos , Hexafluoreto de Enxofre/administração & dosagem , Tomografia Computadorizada por Raios X
10.
Scand J Gastroenterol ; 39(2): 188-94, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15000283

RESUMO

BACKGROUND: Crohn disease (CD) manifests with highly variable signs and symptoms, and assessment of the status of the disease in the single patient can be difficult. This study was conducted to evaluate the efficacy of power colour Doppler ultrasonography, with and without echo-enhancement, in distinguishing active from quiescent CD. METHODS: Resistance Index (RI) of the superior mesenteric artery (SMA), bowel thickness of the affected loops and the presence of colour signals at power Doppler analysis prior to and after ultrasonography contrast agent injection (Levovist) were evaluated in 48 patients with CD. RESULTS: In our series, 26/48 patients had active and 22/48 had quiescent CD. A CDAI score > or = 150 and a pathological (> 5 mg/dL) C reactive protein were significantly correlated with active disease (P < 0.001 and P = 0.004, respectively). Intestinal wall thickness showed no significant correlation with disease status (7.5 +/- 1.3 mm in active disease versus 6.8 +/- 1.3 mm in quiescent disease; P = 0.11). Vascular signals in the affected loops were revealed in 11/22 patients (50%) with active disease and in 5/26 (20%) with quiescent disease (P = 0.052). After Levovist injection, colour signals were found in 22/22 with active and in 8/26 with quiescent CD (P < 0.001). SMA RI was significantly lower in active CD patients (0.81 +/- 0.01 versus 0.83 +/- 0.02; P = 0.001). CONCLUSIONS: Our data suggest that in patients with CD a finding of a SMA RI < or = 0.81, or the presence of a colour signal in the wall of the affected loops, at power Doppler sonography, is indicative of active disease. Utilization of echo-enhancer media can greatly improve the diagnostic sensitivity of intestinal wall power Doppler scan. A finding of intestinal wall thickening is not associated with active disease in our series.


Assuntos
Doença de Crohn/diagnóstico por imagem , Intestinos/diagnóstico por imagem , Artéria Mesentérica Superior/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Proteína C-Reativa/metabolismo , Meios de Contraste , Doença de Crohn/fisiopatologia , Humanos , Artéria Mesentérica Superior/fisiopatologia , Curva ROC , Sensibilidade e Especificidade
11.
Nat Med ; 7(2): 192-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11175850

RESUMO

Metastasis of breast cancer occurs primarily through the lymphatic system, and the extent of lymph node involvement is a key prognostic factor for the disease. Whereas the significance of angiogenesis for tumor progression has been well documented, the ability of tumor cells to induce the growth of lymphatic vessels (lymphangiogenesis) and the presence of intratumoral lymphatic vessels have been controversial. Using a novel marker for lymphatic endothelium, LYVE-1, we demonstrate here the occurrence of intratumoral lymphangiogenesis within human breast cancers after orthotopic transplantation onto nude mice. Vascular endothelial growth factor (VEGF)-C overexpression in breast cancer cells potently increased intratumoral lymphangiogenesis, resulting in significantly enhanced metastasis to regional lymph nodes and to lungs. The degree of tumor lymphangiogenesis was highly correlated with the extent of lymph node and lung metastases. These results establish the occurrence and biological significance of intratumoral lymphangiogenesis in breast cancer and identify VEGF-C as a molecular link between tumor lymphangiogenesis and metastasis.


Assuntos
Neoplasias da Mama/patologia , Fatores de Crescimento Endotelial/fisiologia , Neovascularização Patológica , Animais , Fatores de Crescimento Endotelial/genética , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Linfonodos , Metástase Linfática , Camundongos , Camundongos Nus , Metástase Neoplásica , Células Tumorais Cultivadas , Fator C de Crescimento do Endotélio Vascular
12.
EMBO J ; 19(13): 3272-82, 2000 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-10880440

RESUMO

The function of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in tissue repair has remained controversial. We established transgenic mice with targeted overexpression of TSP-1 in the skin, using a keratin 14 expression cassette. TSP-1 transgenic mice were healthy and fertile, and did not show any major abnormalities of normal skin vascularity, cutaneous vascular architecture, or microvascular permeability. However, healing of full-thickness skin wounds was greatly delayed in TSP-1 transgenic mice and was associated with reduced granulation tissue formation and highly diminished wound angiogenesis. Moreover, TSP-1 potently inhibited fibroblast migration in vivo and in vitro. These findings demonstrate that TSP-1 preferentially interfered with wound healing-associated angiogenesis, rather than with the angiogenesis associated with normal development and skin homeostasis, and suggest that therapeutic application of angiogenesis inhibitors might potentially be associated with impaired wound vascularization and tissue repair.


Assuntos
Tecido de Granulação/fisiologia , Pele/fisiopatologia , Trombospondina 1/fisiologia , Cicatrização/fisiologia , Animais , Sequência de Bases , Permeabilidade Capilar/fisiologia , Movimento Celular/fisiologia , Primers do DNA , Fibroblastos/citologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Queratinócitos/citologia , Camundongos , Camundongos Transgênicos , Neovascularização Fisiológica/fisiologia , Pele/irrigação sanguínea , Trombospondina 1/genética
13.
Am J Pathol ; 156(1): 159-67, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10623663

RESUMO

Inhibition of the vascular endothelial growth factor (VEGF) receptor Flk-1 has been shown to prevent invasion of experimental squamous cell carcinomas (SCC). To directly investigate the role of VEGF in tumor invasion, we stably transfected human SCC-13 cells, which are characterized by a noninvasive phenotype in vivo, with expression vectors containing murine VEGF(164) in sense (SCC/VEGF+) or antisense (SCC/VEGF-) orientation or with vector alone (SCC/vec). SCC/vec cells formed slowly growing, well-differentiated tumors with well-defined borders between tumor and stroma, after intradermal or subcutaneous injection. In contrast, SCC/VEGF+ tumors were characterized by rapid tumor growth, with small cell groups and single cells invading into the surrounding tissue, and by admixture of blood vessels and tumor cells in areas of tumor invasion. We detected an increase in tumor vessel density and size in VEGF-overexpressing tumors, resulting in a more than fourfold increase in total vascular areas. In contrast, SCC/VEGF- clones formed noninvasive, sharply circumscribed tumors with reduced vascular density. These findings demonstrate that selective VEGF overexpression was sufficient to induce tumor invasiveness, and they provide further evidence for an active role of the tumor stroma in cancer progression.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Linfocinas/metabolismo , Animais , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/patologia , Divisão Celular , DNA Complementar/genética , Fatores de Crescimento Endotelial/genética , Humanos , Doenças do Sistema Imunitário/genética , Linfocinas/genética , Camundongos , Camundongos Endogâmicos BALB C/genética , Invasividade Neoplásica/genética , Transplante de Neoplasias , Neovascularização Patológica/patologia , Oligonucleotídeos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Fenótipo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Transfecção , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
14.
Proc Natl Acad Sci U S A ; 96(26): 14888-93, 1999 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-10611308

RESUMO

Recent evidence suggests a potential role for thrombospondin-2 (TSP-2), a matricellular glycoprotein, in the regulation of primary angiogenesis. To directly examine the biological effect of TSP-2 expression on tumor growth and angiogenesis, human A431 squamous cell carcinoma cells, which do not express TSP-2, were stably transfected with a murine TSP-2 expression vector or with vector alone. A431 cells expressing TSP-2 did not show an altered growth rate, colony-forming ability, or susceptibility to induction of apoptosis in vitro. However, injection of TSP-2-transfected clones into the dermis of nude mice resulted in pronounced inhibition of tumor growth that was significantly stronger than the inhibition observed in A431 clones stably transfected with a thrombospondin-1 (TSP-1) expression vector, and combined overexpression of TSP-1 and TSP-2 completely prevented tumor formation. Extensive areas of necrosis were observed in TSP-2-expressing tumors, and both the density and the size of tumor vessels were significantly reduced, although tumor cell expression of the major tumor angiogenesis factor, vascular endothelial growth factor, was maintained at high levels. These findings establish TSP-2 as a potent endogenous inhibitor of tumor growth and angiogenesis.


Assuntos
Inibidores da Angiogênese/metabolismo , Antineoplásicos/metabolismo , Carcinoma de Células Escamosas/prevenção & controle , Neoplasias Experimentais/prevenção & controle , Neovascularização Patológica/prevenção & controle , Trombospondinas/metabolismo , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Recombinantes/metabolismo , Trombospondinas/genética , Células Tumorais Cultivadas
15.
Am J Pathol ; 155(2): 441-52, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10433937

RESUMO

The function of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in epithelial tumor development has remained controversial. We studied the in vitro growth characteristics and the in vivo tumor xenograft growth of the human squamous cell carcinoma cell lines A431 and SCC-13, stably transfected to overexpress human TSP-1. Overexpression of TSP-1 inhibited tumor growth of A431 xenotransplants, and completely abolished tumor formation by SCC-13 cells. TSP-1 overexpressing A431 tumors were characterized by extensive areas of necrosis and by decreased tumor vessel number and size. The effects of TSP-1 on tumor cell growth were indirect since tumor cell proliferation rates in vivo and in vitro, anchorage-dependent and -independent growth in vitro, and susceptibility to induction of apoptosis by serum withdrawal were unchanged in TSP-1 overexpressing tumor cells. However, TSP-1 overexpression up-regulated the TSP-1 receptor CD36, leading to enhanced adhesion of A431 cells to TSP-1. These findings establish TSP-1 as a potent inhibitor of angiogenesis and tumor growth in carcinomas of the skin.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias Cutâneas/metabolismo , Trombospondina 1/metabolismo , Animais , Apoptose , Antígenos CD36/metabolismo , Carcinoma de Células Escamosas/irrigação sanguínea , Adesão Celular , Divisão Celular , Colágeno/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imunoglobulina G/metabolismo , Hibridização In Situ , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Necrose , Neoplasias Cutâneas/irrigação sanguínea , Trombospondina 1/fisiologia , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas , Regulação para Cima
16.
Int J Cancer ; 78(1): 86-94, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9724098

RESUMO

Ro 41-5253 is a RARalpha-selective antagonist that binds RARalpha but does not induce transcriptional activation and does not influence RAR/RXR heterodimerization and DNA binding. This retinoid inhibits proliferation and induces apoptosis in MCF-7 and ZR-75.1 estrogen-receptor-positive breast-carcinoma cells in a dose-dependent way. The anti-proliferative effect is more evident in ZR-75.1 cells than in MCF-7 cells and is probably mediated by anti-AP1 activity, a mechanism known to be implied in the action of several retinoids. In the induction of apoptosis also ZR-75.1 cells are more sensitive to treatment with Ro 41-5253 than MCF-7 cells. In ZR-75.1 cells an apoptotic/hypodiploid DNA peak is already evident after 2 days of incubation, whereas in MCF-7 cells it appears only after 4 days. The highest percentage of apoptotic cells, for both cell lines, is reached after 6 days of treatment. The apoptosis pathway is p53-independent and bcl-2 downregulation seems to be correlated with an increase in TGF-beta1 protein. The MDA-MB-231 estrogen-receptor-negative cell line is poorly responsive to Ro 41-5253 treatment, both in terms of proliferation inhibition and apoptosis induction. Ro 41-5253 has proliferation-inhibiting and apoptosis-inducing properties that are not mediated by transcriptional activation from retinoic-acid response elements. This retinoid antagonist seems to be a compound that exerts an anti-tumor activity but does not induce the toxic side effects of retinoids and might, therefore, be considered as a candidate for cancer therapy.


Assuntos
Apoptose , Benzoatos/farmacologia , Cromanos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Retinoides/farmacologia , Proteína Supressora de Tumor p53/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA , Feminino , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Crescimento Transformador beta/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
17.
Anticancer Res ; 18(2A): 935-42, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9615744

RESUMO

Induction of apoptosis in MCF-7 breast carcinoma cell line by various retinoids was measured by cytofluorimetry and DNA fragmentation assay. Retinoids with marked or high selectivity for RAR alpha, RAR beta, RAR gamma or RXR alpha were tested. All these retinoids were capable of inducing apoptosis, in a dose- and time-dependent way. MCF-7 cell line expressed RAR alpha, RAR gamma and RXRs, but not RAR beta. Compared to untreated MCF-7 cells, after 2 days of incubation with each of the selective retinoids, a substantial increase in apoptotic cells was observed, even at the lowest concentration of 10(-8) M. Among the various analysed selective retinoids only slight differences were observed. All-trans retinoic acid and 13-cis retinoic acid induced apoptosis only after 6 days and 9-cis-retinoic acid after 4 days of incubation. Since all receptor selective retinoids substantially inducedapoptosis, it may be concluded that RAR alpha, RAR gamma and RXR alpha are able to mediate programmed cell death in the tested tumor cell line. Highly selective retinoid receptor agonists and antagonists may be useful for clarifying the function of retinoid receptors and for further progress in the field of cancer prevention and therapy by retinoids.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Receptores do Ácido Retinoico/efeitos dos fármacos , Retinoides/farmacologia , Fatores de Transcrição/efeitos dos fármacos , Neoplasias da Mama/patologia , Fragmentação do DNA , Feminino , Humanos , Receptores do Ácido Retinoico/fisiologia , Receptores X de Retinoides , Fatores de Transcrição/fisiologia , Células Tumorais Cultivadas
18.
Int J Cancer ; 70(5): 619-27, 1997 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-9052765

RESUMO

Interest has been increasingly focused on all-trans-retinoic acid (tRA) and 13-cis-retinoic acid (13cRA) in cancer chemoprevention and treatment. We have examined the in vitro effects of these 2 retinoic acids (RAs) on human breast-cancer cell lines MCF-7 and ZR-75.1 (both estrogen-receptor-positive, ER+) and MDA-MB-231 (estrogen-receptor-negative, ER-), in terms of inhibition of proliferation and induction of apoptosis. Both retinoic acids exerted an evident dose-dependent growth inhibition, although in the ER- cell line the anti-proliferative effect was obtained only with the highest concentration used; the anti-proliferative activity of tRA was more evident than 13cRA on all 3 tested cell lines. tRA and 13cRA induced apoptosis in MCF-7 and MDA-MB-231 cell lines, but not in ZR-75.1. The apoptotic phenomenon was clearly time-dependent, and in our experience it was not related to the arrest in a specific phase of cell cycle. After treatment with RAs the levels of bcl-2 were reduced in MCF-7, while in ZR-75.1 and in MDA-MB-231 no treatment-related modifications were observed. An analysis of estrogen-receptor status, used as a marker of differentiation, demonstrated that after treatment with RAs the levels of estrogen receptor (ER) decreased in ZR-75.1 only. Our study indicates that the anti-proliferative effects of RAs are sustained by induction of apoptosis in MCF-7 and MDA-MB-231 cells, while in ZR-75.1 cells an induction of differentiation without apoptosis was the prevalent mechanism of growth inhibition. Our results encourage further studies on in vivo effects of these retinoids in breast cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Neoplasias da Mama/patologia , Isotretinoína/farmacologia , Tretinoína/farmacologia , Apoptose/genética , Neoplasias da Mama/química , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA , DNA de Neoplasias , Citometria de Fluxo , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/análise , Receptores de Estrogênio/análise , Células Tumorais Cultivadas
19.
Int J Oncol ; 10(3): 597-607, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21533419

RESUMO

We evaluated in vitro the potentiating and/or synergistic antitumor effects among retinoids (all-trans-retinoic acid, tRA, and 13-cis-retinoic acid, 13cRA), alpha-interferon 2a (alpha-IFN 2a) and tamoxifen (TAM) on both estrogen receptor positive (ER(+)) and negative (ER(-)) human breast cancer cell lines. In our experimental model, the three studied agents showed antiproliferative activity in ER(+) cell lines MCF-7 and ZR-75.1, while alpha-IFN 2a was the most effective drug in the ER(-) cell line MDA-MB-231. Retinoids and TAM exerted a strong apoptotic effect in MCF-7 cells, while such an effect was obtained in MDA-MB-231 cells by alpha-IFN 2a. The tested combinations displayed different effects in the different evaluated cell lines: i) in MCF-7 cells tRA + TAM showed additive activity, both tRA + alpha-IFN 2a and TAM + alpha-IFN 2a association displayed a synergistic effect, and a further potentiation of the antiproliferative action was detected with the triple combination; ii) in ZR-75.1 cell line an additive activity was showed by tRA + TAM and TAM + alpha-IFN 2a, while tRA + alpha-IFN 2a produced synergistic action; iii) in MDA-MB-231 cell line only alpha-IFN 2a displayed a strong antiproliferative effect, and no significant potentiation was exerted by any drug association. The feasibility and activity of such combinations have been tested in two pilot clinical trials on patients with metastatic breast cancer: both the tested associations were tolerable, with good treatment compliance and low toxicity. The different antiproliferative and apoptotic effects observed in vitro on apparently similar breast cancer cell lines prompted us to a further investigation of the mutual biological modulations of these drug combinations, in view of a better selection of patients who might potentially benefit from these treatments.

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