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1.
Ann Oncol ; 29(4): 959-965, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29408986

RESUMO

Background: Long-term data with immune checkpoint inhibitors in non-small-cell lung cancer (NSCLC) are limited. Two phase III trials demonstrated improved overall survival (OS) and a favorable safety profile with the anti-programmed death-1 antibody nivolumab versus docetaxel in patients with previously treated advanced squamous (CheckMate 017) and nonsquamous (CheckMate 057) NSCLC. We report results from ≥3 years' follow-up, including subgroup analyses of patients with liver metastases, who historically have poorer prognosis among patients with NSCLC. Patients and methods: Patients were randomized 1 : 1 to nivolumab (3 mg/kg every 2 weeks) or docetaxel (75 mg/m2 every 3 weeks) until progression or discontinuation. The primary end point of each study was OS. Patients with baseline liver metastases were pooled across studies by treatment for subgroup analyses. Results: After 40.3 months' minimum follow-up in CheckMate 017 and 057, nivolumab continued to show an OS benefit versus docetaxel: estimated 3-year OS rates were 17% [95% confidence interval (CI), 14% to 21%] versus 8% (95% CI, 6% to 11%) in the pooled population with squamous or nonsquamous NSCLC. Nivolumab was generally well tolerated, with no new safety concerns identified. Of 854 randomized patients across both studies, 193 had baseline liver metastases. Nivolumab resulted in improved OS compared with docetaxel in patients with liver metastases (hazard ratio, 0.68; 95% CI, 0.50-0.91), consistent with findings from the overall pooled study population (hazard ratio, 0.70; 95% CI, 0.61-0.81). Rates of treatment-related hepatic adverse events (primarily grade 1-2 liver enzyme elevations) were slightly higher in nivolumab-treated patients with liver metastases (10%) than in the overall pooled population (6%). Conclusions: After 3 years' minimum follow-up, nivolumab continued to demonstrate an OS benefit versus docetaxel in patients with advanced NSCLC. Similarly, nivolumab demonstrated an OS benefit versus docetaxel in patients with liver metastases, and remained well tolerated. Clinical trial registration: CheckMate 017: NCT01642004; CheckMate 057: NCT01673867.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Docetaxel/uso terapêutico , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico , Idoso , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/secundário , Docetaxel/efeitos adversos , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Nivolumabe/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Resultado do Tratamento
2.
Recent Results Cancer Res ; 201: 109-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24756788

RESUMO

The epidermal growth factor receptor (EGFR) has been implicated in a multiplicity of cancer-related signal transduction pathways such as cellular proliferation, adhesion, migration, neoangiogenesis and apoptosis inhibition, all of them are important features of cancerogenesis and tumour progression. Its tyrosine kinase activity plays a central role in mediating these processes and has been intensely studied to exploit it as a therapeutic target. Inhibitors of this pathway have been developed and assessed in trials with significant efficacy in clinical applications. The current review focuses in particular on the clinical data of EGFR tyrosine kinase inhibition in different tumour entities, preferably non-small cell lung cancer and pancreatic cancer with emphasis to the approved small molecule erlotinib. Its clinical applications, evidence-based efficacy and toxicity as well as predictive markers of response are discussed.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Quinazolinas/uso terapêutico , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Neoplasias Pancreáticas
4.
Pneumologie ; 64(6): 376-86, 2010 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-20229453

RESUMO

Lung cancer is the leading cause of cancer-related mortality in Germany. Improvements in our understanding of cancer biology have led to the development of novel agents that inhibit the tumour vasculature in order to induce subsequent tumour cell death. In this context, the inhibition of tumour-related angiogenesis - the growth of new vessels from pre-existing vessels - has become an attractive target for anticancer therapy. Bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF), has already been approved in combination with platinum-based chemotherapy in patients with advanced non-small cell lung cancer (NSCLC) without predominant squamous cell histology. Moreover, small molecule inhibitors targeting multiple angiogenic receptors have also shown promise when combined with standard chemotherapy. As a different approach, vascular disrupting agents (VDAs) have been designed to particularly target preexisting blood vessels which may lead to a vascular shut-down. In the present review, both principles of action and current clinical data on anti-angiogenic agents and VDAs in the treatment of patients with NSCLC are reviewed.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos Fitogênicos/administração & dosagem , Morte Celular/efeitos dos fármacos , Aprovação de Drogas , Sistemas de Liberação de Medicamentos , Humanos , Estilbenos/administração & dosagem
5.
Recent Results Cancer Res ; 184: 21-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20072828

RESUMO

The epidermal growth factor receptor (EGFR) has been implicated in a multiplicity of cancer-related signal transduction pathways like cellular proliferation, adhesion, migration, neoangiogenesis, and apoptosis inhibition, all of them important features of cancerogenesis and tumour progression. Its tyrosine kinase activity plays a central role in mediating these processes and has been intensely studied to exploit it as a therapeutic target. Inhibitors of this pathway have been developed and assessed in trials with significant efficacy in clinical applications. The current review focuses in particular on the clinical data of EGFR tyrosine kinase inhibition in different tumour entities, preferably non-small cell lung cancer (NSCLC) and pancreatic cancer with emphasis on the approved small molecule erlotinib. Its clinical applications, evidence-based efficacy, and toxicity as well as predictive markers of response are discussed.


Assuntos
Receptores ErbB/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ensaios Clínicos como Assunto , Cloridrato de Erlotinib , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Quinazolinas/farmacologia
6.
Pneumologie ; 63(5): 289-95, 2009 May.
Artigo em Alemão | MEDLINE | ID: mdl-19418389

RESUMO

Palliative care should be part of respiratory medicine for two reasons: first, many respiratory diseases--besides thoracic tumours--need palliative care in the late stages of the disease. Second, dyspnoea is a common symptom in advanced, primary extrapulmonary diseases and the knowledge of respiratory specialists can be beneficial in the treatment of this symptom. In this paper we describe frequent symptoms of advanced pulmonary diseases and their treatment. Moreover, we focus on the structure of palliative care in Germany.


Assuntos
Dor/etiologia , Dor/prevenção & controle , Cuidados Paliativos/tendências , Pneumologia/tendências , Transtornos Respiratórios/complicações , Transtornos Respiratórios/terapia , Assistência Terminal/tendências , Alemanha , Humanos
7.
Leukemia ; 20(11): 1950-4, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16990775

RESUMO

Neuropilin-1 (NRP-1), a vascular endothelial growth factors and semaphorin receptor functioning as mediator of angiogenesis and neuronal guidance, is expressed by various solid tumors. The importance of NRP-1 in hematological malignancies such as acute myeloid leukemia (AML) remains to be elucidated. Therefore, we determined NRP-1 expression by immunohistochemical analysis of bone marrow biopsies of patients with newly diagnosed, untreated AML. The expression of NRP-1 was significantly increased in AML patients (n = 76; median 12.9 arbitrary units (a.u.)) as compared with controls (n = 38; median 2.75 a.u.). Survival was significantly poorer in patients with high (> median) versus low (< or = median) NRP-1 expression levels with 5-year overall survival rates of 16.9 versus 49.6% (P = 0.050). In conclusion, our data provide evidence of increased NRP-1 expression in AML with significant correlation to survival. Thus, NRP-1 might constitute a promising target for antileukemic and antiangiogenic treatment strategies in AML.


Assuntos
Leucemia Mieloide/metabolismo , Leucemia Mieloide/mortalidade , Neuropilina-1/metabolismo , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Medula Óssea/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Neovascularização Fisiológica/fisiologia , Taxa de Sobrevida
8.
BMC Cancer ; 6: 122, 2006 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-16681848

RESUMO

BACKGROUND: Even today, treatment of Stage III NSCLC still poses a serious challenge. So far, surgical resection is the treatment of choice. Patients whose tumour is not resectable or who are unfit to undergo surgery are usually referred to a combined radio-chemotherapy. However, combined radio-chemotherapeutic treatment is also associated with sometimes marked side effects but has been shown to be more efficient than radiation therapy alone. Nevertheless, there is a significant subset of patients whose overall condition does not permit administration of chemotherapy in a combined-modality treatment. It could be demonstrated though, that NSCLCs often exhibit over-expression of EGF-receptors hence providing an excellent target for the monoclonal EGFR-antagonist cetuximab (Erbitux) which has already been shown to be effective in colorectal as well as head-and-neck tumours with comparatively mild side-effects. METHODS/DESIGN: The NEAR trial is a prospective phase II feasibility study combining a monoclonal EGF-receptor antibody with loco-regional irradiation in patients with stage III NSCLC. This trial aims at testing the combination's efficacy and rate of development of distant metastases with an accrual of 30 patients. Patients receive weekly infusions of cetuximab (Erbitux) plus loco-regional radiation therapy as intensity-modulated radiation therapy. After conclusion of radiation treatment patients continue to receive weekly cetuximab for 13 more cycles. DISCUSSION: The primary objective of the NEAR trial is to evaluate toxicities and feasibility of the combined treatment with cetuximab (Erbitux) and IMRT loco-regional irradiation. Secondary objectives are remission rates, 3-year-survival and local/systemic progression-free survival.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Adulto , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Cetuximab , Terapia Combinada/métodos , Receptores ErbB/antagonistas & inibidores , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Masculino , Estudos Prospectivos
9.
Leuk Lymphoma ; 44(9): 1489-93, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14565649

RESUMO

In analogy to solid neoplasms, accumulating data suggest the requirement of angiogenesis also for the development and progression of hematopoietic malignancies including acute myeloid leukemia (AML). Inhibition of increased microvessel density in bone marrow (BM) might be a promising target for pharmacological interventions aimed at reducing disease activity. Among the putative inhibitors of angiogenesis, thalidomide has demonstrated a considerable efficacy in myelodysplastic syndromes (MDS) and AML with overall response rates up to 56% and 25%, respectively. Responders experienced hematologic improvements with increased hemoglobin and platelet counts resulting in temporary transfusion independence. In AML, partial responses--defined as reduction of the leukemic blast cell infiltration of at least 50% in BM--occurred in four of 20 patients after one month of thalidomide administration in a previous phase I/II study. Additionally, we observed a long-term response in one AML patient of more than 20 months, meanwhile fulfilling the criteria of complete remission. The decrease in leukemic blast infiltration in BM of responders was accompanied by a significant reduction of the microvessel density. Overall adverse events caused by the drug consisted mainly of fatigue, constipation, skin rash and polyneuropathy with a tolerable dose of 200-400 mg p.o. per day. In conclusion, thalidomide as a single agent has significant anti-leukemic activity with some evidence for anti-angiogenic effects in BM, although the precise mechanism of action remains to be elucidated.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Talidomida/uso terapêutico , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Antineoplásicos/efeitos adversos , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Feminino , Humanos , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Projetos Piloto , Estudos Prospectivos , Segurança , Talidomida/efeitos adversos , Resultado do Tratamento
10.
Leukemia ; 16(7): 1302-10, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12094254

RESUMO

Vascular endothelial growth factor (VEGF) and its cellular receptor VEGFR-2 have been implicated as the main endothelial pathway required for tumor neovascularization. However, the importance of the VEGF/VEGFR-2 system for angiogenesis in hematologic malignancies such as AML remains to be elucidated. In 32 patients with newly diagnosed untreated AML, we observed by immunohistochemical analysis of bone marrow biopsies significantly higher levels of VEGF and VEGFR-2 expression than in 10 control patients (P <0.001). In contrast, VEGFR-1 staining levels in AML patients were in the same range as in the controls. Expression of VEGF and VEGFR-2 was significantly higher in patients with a high degree of microvessel density compared to those with a low degree (VEGF: P =0.024; VEGFR-2: P =0.040) and correlated well with bone marrow microvessel density (r(s)=0.566 and 0.609, respectively; P <0.001). Furthermore, in patients who achieved a complete remission following induction chemotherapy VEGFR-2 staining levels decreased into the normal range. In conclusion, our results provide evidence for increased expression of VEGF/VEGFR-2 of leukemic blasts and correlation with angiogenesis in the bone marrow of AML patients. Thus, VEGF/VEGFR-2 might constitute promising targets for antiangiogenic and antileukemic treatment strategies in AML.


Assuntos
Células da Medula Óssea/metabolismo , Fatores de Crescimento Endotelial/biossíntese , Leucemia Mieloide/metabolismo , Linfocinas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Receptores de Fatores de Crescimento/biossíntese , Doença Aguda , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células da Medula Óssea/patologia , Fatores de Crescimento Endotelial/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Linfocinas/genética , Pessoa de Meia-Idade , Neovascularização Patológica , Receptores Proteína Tirosina Quinases/genética , Receptores de Fatores de Crescimento/genética , Receptores Mitogênicos/biossíntese , Receptores Mitogênicos/genética , Receptores de Fatores de Crescimento do Endotélio Vascular , Indução de Remissão , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
11.
Onkologie ; 24 Suppl 5: 75-80, 2001 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-11600818

RESUMO

Angiogenesis in Patients with Hematologic Malignancies The importance of angiogenesis for the progressive growth and viability of solid tumors is well established. Emerging data suggest an involvement of angiogenesis in the pathophysiology of hematologic malignancies as well. Recently, we and others have reported increased angiogenesis in the bone marrow of patients with acute myeloid leukemia (AML) and normalization of bone marrow microvessel density when patients achieved a complete remission (CR) after induction chemotherapy. Tumor angiogenesis depends on the expression of specific mediators that initiate a cascade of events leading to the formation of new microvessels. Among these, VEGF (vascular endothelial growth factor), FGF (fibroblast growth factor) and angiopoietins play a pivotal role in the induction of neovascularization in solid tumors. These cytokines stimulate migration and proliferation of endothelial cells and induce angiogenesis in vivo. Recent data suggest an important role for these mediators in hematologic malignancies as well. Isolated AML blasts overexpress VEGF and VEGF receptor 2. Thus, the VEGF/VEGFR-2 pathway can promote the growth of leukemic blasts in an autocrine and paracrine manner. Therefore, neovascularization and angiogenic mediators/receptors may be promising targets for anti-angiogenic and anti-leukemic treatment strategies. The immunomodulatory drug thalidomide inhibits angiogenesis in animal models. Moreover, it has significant activity in refractory multiple myeloma. In a current phase II study for patients with primary refractory or relapsed multiple myeloma using a combination of thalidomide with hyperfractionated cyclophosphamide and dexamethasone (Hyper-CDT), we observed a partial remission in 12 of 14 evaluable patients (86%). Thus, this combination seems to be very potent. Furthermore, we evaluated the safety and efficacy of thalidomide in patients with AML not qualifying for intensive cytotoxic chemotherapy. 20 patients aged 58-85 (median 69) years were recruited to this phase I/II study and were treated with a dose of 200-400 mg per os daily for a duration of 1-40 (median 6) weeks, dependent on the individual tolerability of the drug. In 4 patients we observed a partial response (PR - defined as more than 50% reduction in leukemic blast infiltration in the bone marrow). This was accompanied by an increase in platelet counts and hemoglobin values. One additional patient showed a significant improvement of peripheral blood counts without fulfilling the criteria of a PR. In parallel, we observed a significant decrease in microvessel density in these 5 patients during treatment with thalidomide. In conclusion, thalidomide seems to have anti-angiogenic as well as anti-leukemic activity in AML. The VEGF/VEGFR-2 pathway seems to play an important role in AML. Therefore, receptor tyrosine kinase inhibitors like SU5416 or SU6668 are currently evaluated in the context of phase II studies in AML. We could recently induce a stable remission in a patient with second relapse of her AML refractory towards chemotherapy by administration of SU5416 (compassionate use), a tyrosine kinase inhibitor of VEGFR-2 and ckit. Current and future studies will clarify the role of anti-angiogenic treatment strategies in AML and other hematologic malignancies.


Assuntos
Medula Óssea/irrigação sanguínea , Neoplasias Hematológicas/patologia , Neovascularização Patológica/patologia , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Masculino , Microcirculação/efeitos dos fármacos , Microcirculação/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/tratamento farmacológico , Talidomida/efeitos adversos , Talidomida/uso terapêutico , Resultado do Tratamento
12.
Blood ; 98(1): 241-3, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11418488

RESUMO

The small molecule receptor tyrosine kinase (RTK) inhibitor SU5416 targets the vascular endothelial growth factor receptor 2 and the stem cell factor receptor c-kit. Herein is described the successful treatment of a 65-year-old woman with SU5416, in second relapse of acute myeloid leukemia (AML) and refractory toward standard chemotherapy regimens. After 12 weeks of treatment with SU5416, the blast cell counts (blood and bone marrow) decreased to undetectable levels and the peripheral blood cell counts normalized with the exception of the platelet count (50-80 x 10(9)/L [50-80 x 10(3)/microL]). The duration of the remission is longer than 4 months during maintenance therapy with SU5416. Microvessel density in the patient's bone marrow dropped from 33.4 to 12.3 microvessels/x500-field 8 weeks after SU5416 administration and remains in the normal range. This is the first report of a stable remission achieved after administration of the RTK inhibitor SU5416 in a patient with AML relapse.


Assuntos
Indóis/administração & dosagem , Leucemia Mieloide/tratamento farmacológico , Pirróis/administração & dosagem , Doença Aguda , Inibidores da Angiogênese/administração & dosagem , Antineoplásicos/administração & dosagem , Células da Medula Óssea/química , Endotélio Vascular/química , Endotélio Vascular/citologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/efeitos dos fármacos , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Indução de Remissão/métodos
13.
Blood ; 95(8): 2637-44, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10753845

RESUMO

The importance of angiogenesis for the progressive growth and viability of solid tumors is well established. In contrast, only few data are available for hematologic neoplasms. To investigate the role of angiogenesis in acute myeloid leukemia (AML), bone marrow biopsies from 62 adults with newly diagnosed, untreated AML (day 0) were evaluated. Further studies were done after the completion of remission induction chemotherapy (day 16 of induction chemotherapy, n = 21; complete remission, n = 20). Microvessels were scored in at least 3 areas (x500 field, 0.126 mm(2)) of the highest microvessel density in representative sections of each bone marrow specimen using immunohistochemistry for von Willebrand factor and thrombomodulin. Microvessel counts were significantly higher in patients with AML (n = 62) compared with control patients (n = 22): median (interquartile range) 24.0 (21.0-27.8)/x500 field vs 11.2 (10. 0-12.0)/x500 field, respectively (P <.001). On day 16 of induction chemotherapy, microvessel density was reduced by 60% (44-66) (P <. 001) in hypoplastic marrows without residual blasts, in contrast to only 17% (0-37) reduction in hypoplastic marrows with >/= 5% residual blasts (P <.001 for the difference between both groups). Bone marrow biopsies taken at the time of complete remission displayed a microvessel density in the same range as the controls. In conclusion, there is evidence of increased microvessel density in the bone marrow of patients with AML, which supports the hypothesis of an important role of angiogenesis in AML. Furthermore, these findings suggest that antiangiogenic therapy might constitute a novel strategy for the treatment of AML. (Blood. 2000;95:2637-2644)


Assuntos
Medula Óssea/irrigação sanguínea , Medula Óssea/patologia , Leucemia Mieloide/patologia , Leucemia Mieloide/fisiopatologia , Neovascularização Patológica , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Feminino , Humanos , Leucemia Mieloide/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
14.
Atherosclerosis ; 145(1): 173-80, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10428308

RESUMO

UNLABELLED: The plasminogen activator (PA)/plasmin system is involved in various pathological processes that are considered important features of atherogenesis and atherothrombosis. These include the proteolysis of fibrin deposits and extracellular matrix components as well as the induction of cell migration and mitogenesis. Tissue-type PA (TPA) is a key enzyme mediating plasminogen to plasmin conversion. TPA plasma concentrations are elevated in patients with advanced atherosclerosis and correlate with an increased risk for myocardial infarction and stroke. In this study, we have analysed the content and expression of TPA in human coronary arteries and their relation to the presence and severity of atherosclerotic lesions. METHODS: Segments of coronary arteries obtained from heart explants (n = 15) were classified by the presence and types of atherosclerotic lesions. TPA was quantitatively determined in protein extracts of intimal and medial layers. In situ hybridization and immunohistochemical analyses were performed on serial sections of representative tissue specimens. RESULTS: PA activity entirely attributable to the presence of active TPA was consistently detected in the protein extracts. Extractable TPA antigen and activity showed a significant graded increase in relation to the presence and severity of atherosclerotic lesions. The ratios of active over total TPA were increased several-fold in extracts of advanced lesions despite a concomitant threefold increase in TPA complexed to its inhibitor PA-1. In macroscopically normal arterial segments and in early lesions, TPA was expressed in the endothelium and in colocalization with vascular smooth muscle cells (VSMCs). In advanced plaques, TPA mRNA was mainly detected in the lateral regions of the fibrous caps in association with migrating VSMCs and in the vicinity of the core areas infiltrated by CD68-positive macrophages. CONCLUSIONS: TPA content and expression is consistently increased in relation to the severity of the lesions in atherosclerotic coronary arteries. This may contribute to plaque destabilization and disruption. Conversely, the increased intramural TPA activity may counteract mural fibrin deposition.


Assuntos
Doença da Artéria Coronariana/metabolismo , Vasos Coronários/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Artérias/metabolismo , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Ativadores de Plasminogênio/metabolismo
15.
AIDS Patient Care STDS ; 13(1): 7-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11362097

RESUMO

A 37-year-old man with hemophilia B, acquired immunodeficiency syndrome, and a unilateral cytomegalovirus retinitis developed a central retinal vein occlusion. This vascular complication occurred despite effective antiviral drug treatment with improvement of the fundus and despite decreased blood coagulability due to hemophilia B. Additional analyses of thrombophilic parameters did not reveal hints of systemic thrombophilia, suggesting that toxic and inflammatory effects of cytomegalovirus itself were responsible for the ophthalmologic aggravation.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Retinite por Citomegalovirus/complicações , Hemofilia B/virologia , Oclusão da Veia Retiniana/virologia , Adulto , Humanos , Masculino , Oclusão da Veia Retiniana/diagnóstico
16.
Thromb Haemost ; 79(3): 579-86, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9531045

RESUMO

Urokinase-type plasminogen activator (UPA) has been implicated in a broad spectrum of pathological processes - e.g. cell adhesion, migration and proliferation and matrix remodeling - that are considered important features of atherogenesis and plaque disruption. In this study, we have analyzed the content and expression of UPA in human coronary arteries and its relation to the presence and severity of atherosclerotic lesions. Segments of coronary arteries obtained from human heart explants (n = 15) were classified by the presence and types of atherosclerotic lesions. UPA was quantitatively determined in protein extracts of the intimal and medial layers. In situ hybridization and immunohistochemical analyses were performed on serial sections of representative tissue specimens. UPA was detected in the extracts as pro-UPA, UPA complexed to plasminogen activator inhibitor-1, or as otherwise inactive UPA antigen, but not in the active two-chain form. Both functional and total UPA were increased several-fold in extracts of advanced lesions, while the ratios of functional over total UPA showed the opposite trend suggesting enhanced UPA inactivation and turnover. UPA expression in early atherosclerotic lesions was particularly prominent in areas of proliferating SMCs in the abluminal part of the neointima, whereas in advanced lesions UPA was widely expressed in macrophage-rich areas adjacent to the rims and shoulder regions of the necrotic cores. The results strongly suggest a causal involvement of UPA in coronary atherogenesis and its clinical outcome.


Assuntos
Doença da Artéria Coronariana/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Doença da Artéria Coronariana/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , RNA Mensageiro/análise
18.
Cardiovasc Res ; 36(1): 28-36, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9415269

RESUMO

OBJECTIVES: Clinical manifestations of coronary heart disease result primarily from the progressive development of atherosclerotic plaques and subsequent thrombus formation: processes which may be accelerated by an enhanced expression of plasminogen activator inhibitor (PAI-1) in the vessel wall. In the present study, content and expression of PAI-1 were comparatively analyzed in human coronary arteries in relation to the presence and severity of atherosclerotic lesions. METHODS: Segments of coronary arteries obtained from heart explants (n = 15) were classified by the presence and types of atherosclerotic lesions. Antigen and activity levels of PAI-1 were determined in protein extracts of intimal and medial layers. In situ hybridization and immunohistochemical analyses were performed on serial sections of representative tissue specimens. RESULTS: Total PAI-1 antigen consistently increased from macroscopically normal areas (MNAs) to early lesions (ELs) and to maximal levels in fibrous (FPs) and calcified (CPs) plaques. No PAI activity was detected, although PAI-1 in its free form was present in all vascular specimens. Both free PAI-1 and PAI-1 complexed with plasminogen activators were significantly increased in extracts of advanced lesions. However, there was a 2-3 fold molar excess of free versus complexed PAI-1 in FPs and CPs. These findings suggest the presence of relevant amounts of PAI-1 in its substrate rather than in its inhibitor conformation in areas of advanced lesions. Compared with MNAs, PAI-1 mRNA was strongly expressed within the thickened intima of ELs. The highest PAI-1 expression was observed in FPs and CPs, being mainly localized in areas surrounding the necrotic cores in co-localization with infiltrating macrophages. CONCLUSIONS: PAI-1 content is consistently increased in relation to the severity of the lesions in atherosclerotic coronary arteries. The concomitant elevation of PAI-1 mRNA suggests that the PAI-1 increase in regulated by local synthesis in the areas of atherosclerotic lesions.


Assuntos
Doença da Artéria Coronariana/metabolismo , Vasos Coronários/química , Inibidor 1 de Ativador de Plasminogênio/análise , Antígenos/análise , Doença da Artéria Coronariana/imunologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Inibidor 1 de Ativador de Plasminogênio/imunologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativadores de Plasminogênio/metabolismo , RNA Mensageiro/análise , Túnica Íntima/química , Túnica Íntima/metabolismo
19.
Arterioscler Thromb Vasc Biol ; 15(7): 893-902, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7600121

RESUMO

Increased expression of plasminogen activator inhibitor-1 (PAI-1) has been demonstrated in the human atherosclerotic vessel wall and may contribute to the impaired plasma fibrinolytic capacity in patients at high risk of atherothrombotic events. In addition, the mural PA/plasmin system may have important pathobiologic functions during atherogenesis. We quantitatively analyzed PAs of the tissue type (TPA) and urokinase type (UPA), PAIs, and plasminogen in protein extracts from different layers of human aorta in relation to the presence and severity of atherosclerotic lesions. In comparison with normal control vessels, intimal and neointimal TPA concentrations were reduced in atherosclerotic aortas except in the necrotic core areas of advanced plaques, where TPA was mainly complexed to PAI-1 in extracellular matrix deposits. In the media, TPA antigen was higher in lesional segments and closely associated with smooth muscle cells. UPA antigen was increased in the intima of atherosclerotic lesions and colocalized with tissue-infiltrating macrophages and neointimal smooth muscle cells. By spectrophotometric assay, neither TPA nor UPA activity could be detected in intimal or medial extracts. PAI-1 concentrations increased significantly in the intima of atherosclerotic segments compared with adjacent uninvolved areas or control aortas. The immunohistochemical distribution of PAI-1 was similar to that observed for TPA. A large excess of PAI-1 over PA concentrations, particularly in the intimal layer, characterizes atherosclerotic lesions of the human aorta and suggests that PA action is locally confined and counterbalanced by enhanced PAI expression and accumulation.


Assuntos
Aorta/química , Arteriosclerose/metabolismo , Ativadores de Plasminogênio/análise , Inativadores de Plasminogênio/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Plasminogênio/análise , Inibidor 1 de Ativador de Plasminogênio/análise , Ativador de Plasminogênio Tecidual/análise , Ativador de Plasminogênio Tipo Uroquinase/análise
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