Circulating endothelial cells (CECs) as well as bone-marrow-derived endothelial precursor cells (EPC) play an important role in neovascularisation and tumour growth. To study the impact of neoadjuvant chemotherapy on the amounts of CEC and their precursor cells, mature CEC and their progenitors were quantified by flow cytometry in peripheral blood of breast cancer patients during anthracycline and/or taxane based neoadjuvant chemotherapy and subsequent surgery in comparison to age-matched healthy controls. Cell numbers were tested for correlation with serum levels of angiopoietin-2, erythropoietin, endostatin, endoglin, VEGF and sVCAM-1 as well as clinical and pathological features of breast cancer disease. Circulating endothelial cells were significantly elevated in breast cancer patients and decreased during chemotherapy, whereas EPC (CD34 þ /VEGFR-2 þ ) as well as their progenitor cell population CD133 þ /CD34 þ and the population of CD34 þ stem cells increased. Concomitantly with the increase of progenitor cells an increase of VEGF, erythropoietin and angiopoietin-2 was observed. These data suggest that chemotherapy can only reduce the amounts of mature CEC, probably reflecting detached cells from tumour vessels, whereas the EPC and their progenitors are mobilised by chemotherapy. Since this mobilisation of EPC may contribute to tumour neovascularisation an early antiangiogenic therapy in combination with chemotherapy could be beneficial for the success of cancer therapy.
The superior vena cava syndrome (SVCS) comprises various symptoms due to occlusion of the SVC, which can be easily obstructed by pathological conditions (eg, lung cancer, due to the low internal venous pressure within rigid structures of the thorax [trachea, right bronchus, aorta]). The resulting increased venous pressure in the upper body may cause edema of the head, neck, and upper extremities, often associated with cyanosis, plethora, and distended subcutaneous vessels. Despite the often striking clinical presentation, SVCS itself is usually not a life-threatening condition. Currently, randomized controlled trials on many clinically important aspects of SVCS are lacking. This review gives an interdisciplinary overview of the pathophysiology, etiology, clinical manifestations, diagnosis, and treatment of malignant SVCS.
Distinct from its receptor binding sites, TNF carries a lectin-like domain, situated at the tip of the molecule, which specifically binds oligosaccharides, such as N,N′-diacetylchitobiose. In view of the apparently conflicting data concerning TNF actions in pulmonary edema, we investigated the contribution of, on the one hand, the receptor binding sites and, in contrast, the lectin-like domain of the cytokine on pulmonary fluid reabsorption in in situ and in vivo flooded rat lungs. Receptor binding sites were blocked with the human soluble TNFR type 1 construct (sTNFR1), whereas the lectin-like domain was blunted with the oligosaccharide N,N′-diacetylchitobiose. We observed that in situ, TNF failed to stimulate alveolar liquid clearance, but did so together with the sTNFR1, and this activity was neutralized by N,N′-diacetylchitobiose. In vivo TNF inhibited liquid clearance, but activated it when complexed with the sTNFR1. A TNF-derived peptide mimic of the lectin-like domain activated fluid reabsorption in flooded lungs, and this activity was blunted by cotreatment with TNF. Our results thus indicate that in these models the receptor binding sites of TNF inhibit, whereas its lectin-like domain activates, edema reabsorption.
Platelet activation contributes to microvascular thrombosis and organ failure in systemic inflammation. We tested the hypothesis whether anti-platelet drugs might favourably affect outcome in patients at risk for organ failure as well as in a mouse model of endotoxin shock. Two hundred twenty-four consecutive patients who were admitted for community acquired pneumonia over a time period of 5 years to a University Hospital were enrolled; about 20% of whom received anti-platelet drugs (acetylsalicylic acid, thienopyridines) for secondary prevention of cardiovascular disease. Patients with anti-platelet drugs were about 12 years old but did not differ in SOFA score and routine laboratory parameters at admission. Logistic regression and 2 x 2 table analysis in age-matched subgroups indicated that anti-platelet drugs may reduce the need of intensive care treatment (odds ratio (OR) 0.32 [95% confidential interval: 0.10-1.00] and 0.19 [0.04-0.87], respectively). In age-matched subgroups, the use of anti-platelet drugs was also associated with a shorter stay in hospital (13.9 +/- 6.2 vs. 18.2 +/- 10.2 days; p < 0.02). In the animal model Balb/c mice were pre-treated with clopidogrel (added to drinking water) for 4 days prior to intraperitoneal (i.p.) administration of endotoxin (lipopolsaccharide (LPS) from Escherichia coli 0111:B4). Within the first 48 hours after LPS there were no differences between clopidogrel and control animals (n = 26 each) in macro-haemodynamics. However, clopidogrel abolished the LPS-induced drop in platelet count and reduced fibrin deposition in lung tissue. Using DNA microarray technology, we could show that clopidogrel suppressed endotoxin-induced up-regulation of inflammation-relevant genes, including arachidonate-5-lipoxygenase activating protein and leukotriene B4 receptor 1. According to our data a possible benefit of anti-platelet drugs in patients on risk for systemic inflammation and organ failure should be tested in a prospective trial.
Rationale: Alveolar liquid clearance is regulated by Na 1 uptake through the apically expressed epithelial sodium channel (ENaC) and basolaterally localized Na 1 -K 1 -ATPase in type II alveolar epithelial cells. Dysfunction of these Na 1 transporters during pulmonary inflammation can contribute to pulmonary edema.Objectives: In this study, we sought to determine the precise mechanism by which the TIP peptide, mimicking the lectin-like domain of tumor necrosis factor (TNF), stimulates Na 1 uptake in a homologous cell system in the presence or absence of the bacterial toxin pneumolysin (PLY).Methods: We used a combined biochemical, electrophysiological, and molecular biological in vitro approach and assessed the physiological relevance of the lectin-like domain of TNF in alveolar liquid clearance in vivo by generating triple-mutant TNF knock-in mice that express a mutant TNF with deficient Na 1 uptake stimulatory activity.Measurements and Main Results: TIP peptide directly activates ENaC, but not the Na 1 -K 1 -ATPase, upon binding to the carboxyterminal domain of the a subunit of the channel. In the presence of PLY, a mediator of pneumococcal-induced pulmonary edema, this binding stabilizes the ENaC-PIP2-MARCKS complex, which is necessary for the open probability conformation of the channel and preserves ENaC-a protein expression, by means of blunting the protein kinase C-a pathway. Triple-mutant TNF knock-in mice are more prone than wild-type mice to develop edema with low-dose intratracheal PLY, correlating with reduced pulmonary ENaC-a subunit expression.Conclusions: These results demonstrate a novel TNF-mediated mechanism of direct ENaC activation and indicate a physiological role for the lectin-like domain of TNF in the resolution of alveolar edema during inflammation.
Objective To test the hypothesis that the lectin-like domain of tumor necrosis factor, mimicked by the TIP peptide, can improve lung function after unilateral orthotopic lung isotransplantation. Because of a lack of a specific treatment for ischemia reperfusion-mediated lung injury, accompanied by a disrupted barrier integrity and a dysfunctional alveolar liquid clearance, alternative therapies restoring these parameters after lung transplantation are required. Design Prospective, randomized laboratory investigation. Setting University-affiliated laboratory. Subjects Adult female rats. Interventions Tuberoinfundibular peptide, mimicking the lectin-like domain of tumor necrosis factor, mutant TIP peptide, N,N′-diacetylchitobiose/TIP peptide, and amiloride/TIP peptide were instilled intratracheally in the left lung immediately before the isotransplantation was performed. An additional group received an intravenous TIP peptide treatment, 1.5 mins before transplantation. Studies using isolated rat type II alveolar epithelial cell monolayers and ovine pulmonary endothelial cells were also performed. Measurements and Main Results Intratracheal pretreatment of the transplantable left lung with the TIP peptide, but not with an inactive mutant TIP peptide, resulted in significantly improved oxygenation 24 hrs after transplantation. This treatment led to a significantly reduced neutrophil content in the lavage fluid. Both the effects on oxygenation and neutrophil infiltration were inhibited by the epithelial sodium channel blocker amiloride. The TIP peptide blunted reactive oxygen species production in pulmonary artery endothelial cells under hypoxia and reoxygenation and reduced reactive oxygen species content in the transplanted rat lungs in vivo. Ussing chamber experiments using monolayers of primary type II rat pneumocytes indicated that the primary site of action of the peptide was on the apical side of these cells. Conclusions These data demonstrate that the TIP peptide significantly improves lung function after lung transplantation in the rat, in part, by reducing neutrophil content and reactive oxygen species generation. These studies suggest that the TIP peptide is a potential therapeutic agent against the ischemia reperfusion injury associated with lung transplantation.
Tumor necrosis factor-alpha (TNF-alpha) activates sodium channels in Type II alveolar epithelial cells, an important mechanism for the reported fluid resorption capacity of the cytokine. Both TNF-alpha receptor-dependent and -independent effects were proposed for this activity in vitro, the latter mechanism mediated by the lectin-like domain of the molecule. In this study, the relative contribution of the receptor-dependent versus receptor-independent activities was investigated in an in situ mouse lung model and an ex vivo rat lung model. Fluid resorption due to murine TNF-alpha (mTNF-alpha) was functional in mice that were genetically deficient in both types of mTNF-alpha receptor, establishing the importance of mTNF-alpha receptor-independent effects in this species. In addition, we assessed the capacity of an mTNF-alpha-derived peptide (mLtip), which activates sodium transport by a receptor-independent mechanism, to reduce lung water content in an isolated, ventilated, autologous blood-perfused rat lung model. The results show that in this model, mLtip, in contrast to mTNF-alpha, produced a progressive recovery of dynamic lung compliance and airway resistance after alveolar flooding. There was also a significant reduction in lung water. These results indicate that the receptor-independent lectin-like domain of mTNF-alpha has a potential physiological role in the resolution of alveolar edema in rats and mice.
Interstitial lung disease (ILD) is a complication of polymyositis (PM) and dermatomyositis (DM). It often manifests itself in association with myositis-specific antisynthetase autoantibodies, among which anti-Jo-1 antibodies are the most commonly encountered. In contrast, ILD associated with anti-Jo-1 antibodies without muscle involvement is rare and not well characterized. We report four patients presenting with ILD associated with anti-Jo-1 antibodies. Histological findings of transbronchial biopsies disclosed a pattern consistent with nonspecific interstitial pneumonitis, a CD8+ lymphocytosis was found in bronchoalveolar lavage. Only one of these patients developed an "antisynthetase syndrome" with PM, after nearly 2 yrs of severe ILD. The clinical conditions of all four cases showed stabilization or improvement when cyclosporine was added to their immunosuppressive treatment. These cases confirm that a CD8+ lymphocytic interstitial lung disease may be the first, and sole manifestation of autoimmune disease associated with anti-Jo-1 antibodies. Furthermore, they suggest that this form of interstitial lung disease apparently has a poor response to steroids and cytotoxic drugs, but may respond to moderate doses of cyclosporine and azathioprine in addition to low doses of steroids.
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