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1.
Curr Oncol ; 20(4): 212-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23904762

RESUMO

BACKGROUND: Sexually transmitted infection with the human papillomavirus (hpv) is responsible for a significant burden of human cancers involving the cervix, anogenital tract, and oropharynx. Studies in the United States and Europe have demonstrated an alarming increase in the frequency of hpv-positive oropharyngeal cancer, but the same direct evidence does not exist in Canada. METHODS: Using the London Health Sciences Centre pathology database, we identified tonsillar cancers diagnosed between 1993 and 2011. Real-time polymerase chain reaction was then used on pre-treatment primary-site biopsy samples to test for dna from the high-risk hpv types 16 and 18. The study cohort was divided into three time periods: 1993-1999, 2000-2005, and 2006-2011. RESULTS: Of 160 tumour samples identified, 91 (57%) were positive for hpv 16. The total number of tonsillar cancers significantly increased from 1993-1999 to 2006-2011 (32 vs. 68), and the proportion of cases that were hpv-positive substantially increased (25% vs. 62%, p < 0.002). Those changes were associated with a marked improvement in 5-year overall survival (39% in 1993-1999 vs. 84% in 2006-2011, p < 0.001). When all factors were included in a multivariable model, only hpv status predicted treatment outcome. INTERPRETATION: The present study is the first to provide direct evidence that hpv-related oropharyngeal cancer is increasing in incidence in a Canadian population. Given the long lag time between hpv infection and clinically apparent malignancy, oropharyngeal cancer will be a significant clinical problem for the foreseeable future despite vaccination efforts.

2.
Circulation ; 101(20): 2382-7, 2000 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-10821814

RESUMO

BACKGROUND: We recently described autoantibodies (angiotensin-1 receptor autoantibodies, AT(1)-AA) directed at the AT(1) receptor in the serum of preeclamptic patients, whose placentas are commonly infarcted and express tissue factor (TF). Mechanisms of how AT(1)-AA might contribute to preeclampsia are unknown. We tested the hypothesis that AT(1)-AA cause vascular smooth muscle cells (VSMC) to express TF. METHODS AND RESULTS: IgG from preeclamptic patients containing AT(1)-AA was purified with anti-human IgG columns. AT(1)-AA were separated from the IgG by ammonium sulfate precipitation. We transfected Chinese hamster ovary cells overexpressing the AT(1) receptor with TF promoter constructs coupled to a luciferase reporter gene. VSMC were obtained from human coronary arteries. Extracellular signal-related kinase activation was detected by an in-gel kinase assay. AP-1 activation was determined by electromobility shift assay. TF was measured by ELISA and detected by immunohistochemistry. Placentas from preeclamptic women stained strongly for TF, whereas control placentas showed far less staining. We proved AT(1)-AA specificity by coimmunoprecipitating the AT(1) receptor with AT(1)-AA but not with nonspecific IgG. Angiotensin (Ang) II and AT(1)-AA both activated extracellular signal-related kinase, AP-1, and the TF promoter transfected VSMC and Chinese hamster ovary cells, but only when the AP-1 binding site was present. We then demonstrated TF expression in VSMC exposed to either Ang II or AT(1)-AA. All these effects were blocked by losartan. Nonspecific IgG or IgG from nonpreeclamptic pregnant women had a negligible effect. CONCLUSIONS: We conclude that AT(1)-AA and Ang II both stimulate the AT(1) receptor and initiate a signaling cascade resulting in TF expression. These results show an action of AT(1)-AA on human cells that could contribute to the pathogenesis of preeclampsia.


Assuntos
Anticorpos/farmacologia , Vasos Coronários/metabolismo , Pré-Eclâmpsia/imunologia , Receptores de Angiotensina/agonistas , Receptores de Angiotensina/imunologia , Tromboplastina/metabolismo , Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina , Animais , Células CHO , Células Cultivadas , Vasos Coronários/citologia , Vasos Coronários/efeitos dos fármacos , Cricetinae , Ativação Enzimática , Feminino , Humanos , Losartan/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Valores de Referência , Tromboplastina/genética , Fator de Transcrição AP-1/fisiologia , Transfecção
3.
Circulation ; 104(5): 576-81, 2001 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-11479256

RESUMO

BACKGROUND: 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have effects that extend beyond cholesterol reduction. We used an angiotensin (Ang) II-dependent model to test the hypothesis that cerivastatin ameliorates cardiac injury. METHODS AND RESULTS: We treated rats transgenic for human renin and angiotensinogen (dTGR) chronically from weeks 4 to 7 with cerivastatin (0.5 mg/kg by gavage). We used immunohistochemistry, electrophoretic mobility shift assays, and reverse transcription-polymerase chain reaction techniques. Compared with control dTGR, dTGR treated with cerivastatin had reduced mortality, blood pressure, cardiac hypertrophy, macrophage infiltration, and collagen I, laminin, and fibronectin deposition. Basic fibroblast growth factor mRNA and protein expression were markedly reduced, as was interleukin-6 expression. The transcription factors NF-kappaB and AP-1 were substantially less activated, although plasma cholesterol was not decreased. CONCLUSIONS: These results suggest that statins ameliorate Ang II-induced hypertension, cardiac hypertrophy, fibrosis, and remodeling independently of cholesterol reduction. Although the clinical significance remains uncertain, the results suggest that statins interfere with Ang II-induced signaling and transcription factor activation, thereby ameliorating end-organ damage.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Piridinas/farmacologia , Angiotensina II/metabolismo , Angiotensinogênio/genética , Angiotensinogênio/metabolismo , Animais , Animais Geneticamente Modificados , Pressão Sanguínea/efeitos dos fármacos , Antígenos CD4/análise , Antígenos CD8/análise , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/mortalidade , Colágeno/análise , Fator 2 de Crescimento de Fibroblastos/genética , Fibronectinas/análise , Regulação da Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Imuno-Histoquímica , Interleucina-6/genética , Masculino , Miocárdio/química , Miocárdio/metabolismo , Miocárdio/patologia , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Oligonucleotídeos/metabolismo , Ligação Proteica , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Renina/genética , Renina/metabolismo , Análise de Sobrevida , Taxa de Sobrevida , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo
4.
Hypertension ; 35(1 Pt 2): 193-201, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10642297

RESUMO

We recently reported that the activation of nuclear factor-kappaB (NF-kappaB) promotes inflammation in rats harboring both human renin and angiotensinogen genes (double-transgenic rats [dTGR]). We tested the hypothesis that the antioxidant pyrrolidine dithiocarbamate (PDTC) inhibits NF-kappaB and ameliorates renal and cardiac end-organ damage. dTGR feature hypertension, severe renal and cardiac damage, and a 40% mortality rate at 7 weeks. Electrophoretic mobility shift assay showed increased NF-kappaB DNA binding activity in hearts and kidneys of dTGR. Chronic PDTC (200 mg/kg SC) treatment decreased blood pressure (162+/-8 versus 190+/-7 mm Hg; P=0.02) in dTGR compared with dTGR controls. The cardiac hypertrophy index was also significantly reduced (4.90+/-0.1 versus 5.77+/-0.1 mg/g; P<0. 001). PDTC reduced 24-hour albuminuria by >95% (2.5+/-0.8 versus 57. 1+/-8.7 mg/d; P<0.001) and prevented death. Vascular injury was ameliorated in small renal and cardiac vessels. Electrophoretic mobility shift assay showed that PDTC inhibited NF-kappaB binding activity in heart and kidney, whereas AP-1 activity in the kidney was not decreased. dTGR exhibited increased left ventricular c-fos and c-jun mRNA expression. PDTC treatment reduced c-fos but not c-jun mRNA. Immunohistochemistry showed increased p65 NF-kappaB subunit expression in the endothelium and smooth muscle cells of damaged small vessels, as well as infiltrating cells in glomeruli, tubules, and collecting ducts of dTGR. PDTC markedly reduced the immunoreactivity of p65. PDTC also prevented the NF-kappaB-dependent transactivation of the intercellular adhesion molecule ICAM-1 and inducible nitric oxide synthase. Monocyte infiltration was markedly increased in dTGR kidneys and hearts. Chronic treatment reduced monocyte/macrophage infiltration by 72% and 64%, respectively. Thus, these results demonstrate that PDTC inhibits NF-kappaB activity, ameliorates inflammation, and protects against angiotensin II-induced end-organ damage.


Assuntos
Angiotensina II/genética , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Vasculite/enzimologia , Vasculite/imunologia , Animais , Animais Geneticamente Modificados , Antioxidantes/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Quimiocina CCL2/genética , Circulação Coronária , Doença das Coronárias/enzimologia , Doença das Coronárias/genética , Doença das Coronárias/patologia , DNA/metabolismo , Expressão Gênica/imunologia , Humanos , Hipertensão/enzimologia , Hipertensão/imunologia , Hipertensão/patologia , Molécula 1 de Adesão Intercelular/genética , Nefropatias/enzimologia , Nefropatias/genética , Nefropatias/patologia , Masculino , NF-kappa B/análise , Óxido Nítrico Sintase/metabolismo , Ligação Proteica/efeitos dos fármacos , Pirrolidinas/farmacologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Circulação Renal , Renina/genética , Tiocarbamatos/farmacologia , Fator de Transcrição AP-1/genética , Vasculite/patologia
7.
J Craniofac Genet Dev Biol ; 6(2): 139-50, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3722340

RESUMO

On the basis of cephalometric, roentgencephalometric, tomographic, and somatoscopic studies of 81 adult males with unilateral microtia, investigations were carried out into the interrelation between the degree of involvement of the outer and middle ear and of the face; between the degree of mutual involvement of individual facial structures; and between the malformation of these structures and the degree of outer and middle ear anomalies. A significant relationship between the extent of damage to the main branchiogenic components (outer ear-middle ear-face) was found exclusively in individuals with highly severe or with very slight involvement. Therefore, the correlation coefficients were not characteristic for the predominant majority of our patients and their values were influenced by the frequency of marginal variants of the anomaly within the series. The calculations of the correlation coefficients for the whole variation range of the anomaly thus were meaningless. This knowledge could have general repercussions. Slight interrelations among the degrees of damage of certain facial structures showed at the same time the individual variability of facial configuration within this group of anomalies. Our findings were in good agreement with the experimentally documented hypothesis on the hematogenic origin of branchiogenic malformations and with the assumption based on this hypothesis. Facial asymmetry represents an important prognostic sign for the assessment of the extent of middle ear damage.


Assuntos
Orelha Externa/anormalidades , Orelha Média/anormalidades , Ossos Faciais/anormalidades , Adulto , Cefalometria , Humanos , Masculino
8.
Cesk Otolaryngol ; 38(2): 106-13, 1989 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-2731253

RESUMO

Based on examination of 80 adult men with unilateral microtia the authors examined the relationship between the affection of the ear lobe, middle ear and face. The revealed significant relations were due solely to subjects with the most severe or with the slightest affection. Correlation coefficients therefore do not characterize relations in the majority of patients and their magnitude is influenced by the ratio of marginal variants of the anomaly in the group. The calculation of the relationship for the entire range of variation of the defect thus is useless. These findings may have a more general validity. They are consistent with the experimental evidence on a haematogenic origin of branchiogenic defects and assumptions derived from this hypothesis. Facial asymmetry is a prognostically important sign for the estimation of the extent of damage of the middle ear.


Assuntos
Orelha Externa/anormalidades , Orelha Média/anormalidades , Assimetria Facial/patologia , Adulto , Humanos , Masculino
9.
Am J Pathol ; 157(1): 111-22, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10880382

RESUMO

Tissue factor (TF), a main initiator of clotting, is up-regulated in vasculopathy. We tested the hypothesis that chronic in vivo angiotensin (ANG) II receptor AT(1) receptor blockade inhibits TF expression in a model of ANG II-induced cardiac vasculopathy. Furthermore, we explored the mechanisms by examining transcription factor activation and analyzing the TF promoter. Untreated transgenic rats overexpressing the human renin and angiotensinogen genes (dTGR) feature hypertension and severe left ventricular hypertrophy with focal areas of necrosis, and die at age 7 weeks. Plasma and cardiac ANG II was three- to fivefold increased compared to Sprague-Dawley rats. Chronic treatment with valsartan normalized blood pressure and coronary resistance completely, and ameliorated cardiac hypertrophy (P < 0.001). Valsartan prevented monocyte/macrophage infiltration, nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) activation, and c-fos expression in dTGR hearts. NF-kappaB subunit p65 and TF expression was increased in the endothelium and media of cardiac vessels and markedly reduced by valsartan treatment. To analyze the mechanism of TF transcription, we then transfected human coronary artery smooth muscle cells and Chinese hamster ovary cells overexpressing the AT(1) receptor with plasmids containing the human TF promoter and the luciferase reporter gene. ANG II induced the full-length TF promoter in both transfected cell lines. TF transcription was abolished by AT(1) receptor blockade. Deletion of both AP-1 and NF-kappaB sites reduced ANG II-induced TF gene transcription completely, whereas the deletion of AP-1 sites reduced transcription. Thus, the present study clearly shows an aberrant TF expression in the endothelium and media in rats with ANG II-induced vasculopathy. The beneficial effects of AT(1) receptor blockade in this model are mediated via the inhibition of NF-kappaB and AP-1 activation, thereby preventing TF expression, cardiac vasculopathy, and microinfarctions.


Assuntos
Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina , Doença das Coronárias/metabolismo , Tromboplastina/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Anti-Hipertensivos/farmacologia , Fatores de Coagulação Sanguínea/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Células CHO , Linhagem Celular , Doença das Coronárias/induzido quimicamente , Doença das Coronárias/mortalidade , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Cricetinae , Proteínas da Matriz Extracelular/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Humanos , Inflamação/fisiopatologia , Integrina alfa4beta1 , Integrinas/efeitos dos fármacos , Integrinas/metabolismo , NF-kappa B/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Retorno de Linfócitos/efeitos dos fármacos , Receptores de Retorno de Linfócitos/metabolismo , Tetrazóis/farmacologia , Tromboplastina/genética , Tromboplastina/metabolismo , Fator de Transcrição AP-1/metabolismo , Valina/análogos & derivados , Valina/farmacologia , Valsartana , Resistência Vascular/efeitos dos fármacos
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