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1.
Ann Oncol ; 29(4): 959-965, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29408986

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Docetaxel/therapeutic use , Liver Neoplasms/secondary , Lung Neoplasms/drug therapy , Nivolumab/therapeutic use , Aged , Antineoplastic Agents/adverse effects , Carcinoma, Non-Small-Cell Lung/secondary , Docetaxel/adverse effects , Female , Follow-Up Studies , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Nivolumab/adverse effects , Randomized Controlled Trials as Topic , Survival Analysis , Treatment Outcome
2.
Recent Results Cancer Res ; 201: 109-23, 2014.
Article in English | MEDLINE | ID: mdl-24756788

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Pancreatic Neoplasms/drug therapy , Quinazolines/therapeutic use , Animals , Carcinoma, Hepatocellular/drug therapy , ErbB Receptors/antagonists & inhibitors , Erlotinib Hydrochloride , Humans , Liver Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Pancreatic Neoplasms
4.
Pneumologie ; 64(6): 376-86, 2010 Jun.
Article in German | MEDLINE | ID: mdl-20229453

ABSTRACT

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.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/blood supply , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/blood supply , Lung Neoplasms/drug therapy , Antineoplastic Agents, Phytogenic/administration & dosage , Cell Death/drug effects , Drug Approval , Drug Delivery Systems , Humans , Stilbenes/administration & dosage
5.
Recent Results Cancer Res ; 184: 21-31, 2010.
Article in English | MEDLINE | ID: mdl-20072828

ABSTRACT

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.


Subject(s)
ErbB Receptors/antagonists & inhibitors , Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Quinazolines/therapeutic use , Animals , Carcinoma, Non-Small-Cell Lung/drug therapy , Clinical Trials as Topic , Erlotinib Hydrochloride , Humans , Liver Neoplasms/drug therapy , Lung Neoplasms/drug therapy , Pancreatic Neoplasms/drug therapy , Quinazolines/pharmacology
6.
Pneumologie ; 63(5): 289-95, 2009 May.
Article in German | MEDLINE | ID: mdl-19418389

ABSTRACT

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.


Subject(s)
Pain/etiology , Pain/prevention & control , Palliative Care/trends , Pulmonary Medicine/trends , Respiration Disorders/complications , Respiration Disorders/therapy , Terminal Care/trends , Germany , Humans
7.
Leukemia ; 20(11): 1950-4, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16990775

ABSTRACT

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.


Subject(s)
Leukemia, Myeloid/metabolism , Leukemia, Myeloid/mortality , Neuropilin-1/metabolism , Acute Disease , Adult , Aged , Aged, 80 and over , Biopsy , Bone Marrow/metabolism , Disease-Free Survival , Female , Humans , Immunohistochemistry , Leukemia, Myeloid/pathology , Male , Middle Aged , Neovascularization, Physiologic/physiology , Survival Rate
8.
BMC Cancer ; 6: 122, 2006 May 08.
Article in English | MEDLINE | ID: mdl-16681848

ABSTRACT

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.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Radiotherapy, Intensity-Modulated , Adult , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/adverse effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/radiotherapy , Cetuximab , Combined Modality Therapy/methods , ErbB Receptors/antagonists & inhibitors , Feasibility Studies , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/radiotherapy , Male , Prospective Studies
9.
Leuk Lymphoma ; 44(9): 1489-93, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14565649

ABSTRACT

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.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antineoplastic Agents/therapeutic use , Leukemia, Myeloid/drug therapy , Thalidomide/therapeutic use , Acute Disease , Aged , Aged, 80 and over , Angiogenesis Inhibitors/adverse effects , Antineoplastic Agents/adverse effects , Bone Marrow/drug effects , Bone Marrow/pathology , Clinical Trials, Phase I as Topic , Clinical Trials, Phase II as Topic , Female , Humans , Leukemia, Myeloid/pathology , Male , Middle Aged , Myelodysplastic Syndromes/drug therapy , Neovascularization, Pathologic/drug therapy , Pilot Projects , Prospective Studies , Safety , Thalidomide/adverse effects , Treatment Outcome
10.
Leukemia ; 16(7): 1302-10, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12094254

ABSTRACT

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.


Subject(s)
Bone Marrow Cells/metabolism , Endothelial Growth Factors/biosynthesis , Leukemia, Myeloid/metabolism , Lymphokines/biosynthesis , Receptor Protein-Tyrosine Kinases/biosynthesis , Receptors, Growth Factor/biosynthesis , Acute Disease , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Marrow Cells/pathology , Endothelial Growth Factors/genetics , Gene Expression Regulation, Neoplastic , Humans , Leukemia, Myeloid/drug therapy , Leukemia, Myeloid/genetics , Leukemia, Myeloid/pathology , Lymphokines/genetics , Middle Aged , Neovascularization, Pathologic , Receptor Protein-Tyrosine Kinases/genetics , Receptors, Growth Factor/genetics , Receptors, Mitogen/biosynthesis , Receptors, Mitogen/genetics , Receptors, Vascular Endothelial Growth Factor , Remission Induction , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
11.
Onkologie ; 24 Suppl 5: 75-80, 2001 Sep.
Article in German | MEDLINE | ID: mdl-11600818

ABSTRACT

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.


Subject(s)
Bone Marrow/blood supply , Hematologic Neoplasms/pathology , Neovascularization, Pathologic/pathology , Aged , Aged, 80 and over , Bone Marrow/drug effects , Clinical Trials as Topic , Female , Hematologic Neoplasms/drug therapy , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/pathology , Male , Microcirculation/drug effects , Microcirculation/pathology , Middle Aged , Neovascularization, Pathologic/drug therapy , Thalidomide/adverse effects , Thalidomide/therapeutic use , Treatment Outcome
12.
Blood ; 98(1): 241-3, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11418488

ABSTRACT

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.


Subject(s)
Indoles/administration & dosage , Leukemia, Myeloid/drug therapy , Pyrroles/administration & dosage , Acute Disease , Angiogenesis Inhibitors/administration & dosage , Antineoplastic Agents/administration & dosage , Bone Marrow Cells/chemistry , Endothelium, Vascular/chemistry , Endothelium, Vascular/cytology , Female , Humans , Immunohistochemistry , Middle Aged , Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/drug effects , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/drug effects , Receptors, Growth Factor/metabolism , Receptors, Vascular Endothelial Growth Factor , Remission Induction/methods
13.
Blood ; 95(8): 2637-44, 2000 Apr 15.
Article in English | MEDLINE | ID: mdl-10753845

ABSTRACT

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)


Subject(s)
Bone Marrow/blood supply , Bone Marrow/pathology , Leukemia, Myeloid/pathology , Leukemia, Myeloid/physiopathology , Neovascularization, Pathologic , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/therapeutic use , Antineoplastic Agents/therapeutic use , Female , Humans , Leukemia, Myeloid/drug therapy , Male , Middle Aged
14.
Atherosclerosis ; 145(1): 173-80, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10428308

ABSTRACT

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.


Subject(s)
Coronary Artery Disease/metabolism , Coronary Vessels/metabolism , Tissue Plasminogen Activator/metabolism , Arteries/metabolism , Coronary Artery Disease/pathology , Coronary Vessels/pathology , Humans , Immunohistochemistry , In Situ Hybridization , Plasminogen Activators/metabolism
15.
AIDS Patient Care STDS ; 13(1): 7-9, 1999 Jan.
Article in English | MEDLINE | ID: mdl-11362097

ABSTRACT

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.


Subject(s)
AIDS-Related Opportunistic Infections/complications , Cytomegalovirus Retinitis/complications , Hemophilia B/virology , Retinal Vein Occlusion/virology , Adult , Humans , Male , Retinal Vein Occlusion/diagnosis
16.
Thromb Haemost ; 79(3): 579-86, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9531045

ABSTRACT

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.


Subject(s)
Coronary Artery Disease/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Coronary Artery Disease/pathology , Humans , Immunohistochemistry , In Situ Hybridization , RNA, Messenger/analysis
18.
Cardiovasc Res ; 36(1): 28-36, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9415269

ABSTRACT

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.


Subject(s)
Coronary Artery Disease/metabolism , Coronary Vessels/chemistry , Plasminogen Activator Inhibitor 1/analysis , Antigens/analysis , Coronary Artery Disease/immunology , Gene Expression , Humans , Immunohistochemistry , In Situ Hybridization , Plasminogen Activator Inhibitor 1/immunology , Plasminogen Activator Inhibitor 1/metabolism , Plasminogen Activators/metabolism , RNA, Messenger/analysis , Tunica Intima/chemistry , Tunica Intima/metabolism
19.
Arterioscler Thromb Vasc Biol ; 15(7): 893-902, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7600121

ABSTRACT

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.


Subject(s)
Aorta/chemistry , Arteriosclerosis/metabolism , Plasminogen Activators/analysis , Plasminogen Inactivators/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Humans , Immunohistochemistry , Middle Aged , Plasminogen/analysis , Plasminogen Activator Inhibitor 1/analysis , Tissue Plasminogen Activator/analysis , Urokinase-Type Plasminogen Activator/analysis
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