Epstein-Barr virus (EBV)-associated posttransplant smooth muscle tumors (PTSMT)are very rare complications. We aimed to provide a clinicopathological characterization which is based on our own case series (n = 5) as well as previously reported PTSMT cases (n = 63). Meta-analysis of PTSMT and molecular analysis of tumor cells from our cohort was performed. Most PTSMT developed in kidney-transplanted patients (n = 41/68, 60%). Liver/transplant liver was the main site of manifestation (n = 38/68, 56%). Tumors occurred after a median interval of 48 months (range 5-348) and developed earlier in children than in adults. Most tumors showed no marked cellular atypia, low mitosis rate and no tumor necrosis. Gene expression analysis of 20 EBV-related genes, including two microRNAs, revealed overexpression of MYC (p = 0.0357). Therapy was mainly based on surgical resection or reduced immunosuppression but no significant differences in overall survival were evident. Lower overall survival was associated with multiorgan involvement (n = 33/68, 48.5%) and particularly with intracranial PTSMT manifestation (n = 7/68, 10%; p < 0.02), but not transplant involvement (n = 11/68, 16%). In summary, PTSMT differ from conventional leiomyosarcomas by their lack of marked atypia, unusual sites of involvement and defining EBV association. Surgery and reduced immunosuppression show comparable clinical results and prognosis is associated with intracranial manifestation.
The rationale of α1-antitrypsin (AAT) augmentation therapy to treat progressive emphysema in AAT-deficient patients is based on inhibition of neutrophil elastase; however, the benefit of this treatment remains unclear. Here we show that clinical grade AAT (with elastase inhibitory activity) and a recombinant form of AAT (rAAT) without anti-elastase activity reduces lung inflammatory responses to LPS in elastase-deficient mice. WT and elastasedeficient mice treated with either native AAT or rAAT exhibited significant reductions in infiltrating neutrophils (23% and 68%), lavage fluid levels of TNF-α (70% and 80%), and the neutrophil chemokine KC (CXCL1) (64% and 90%), respectively. Lung parenchyma TNF-α, DNA damage-inducible transcript 3 and X-box binding protein-1 mRNA levels were reduced in both mouse strains treated with AAT; significantly lower levels of these genes, as well as IL-1β gene expression, were observed in lungs of AAT-deficient patients treated with AAT therapy compared with untreated patients. In vitro, LPS-induced cytokines from WT and elastasedeficient mouse neutrophils, as well as neutrophils of healthy humans, were similarly reduced by AAT or rAAT; human neutrophils adhering to endothelial cells were decreased by 60-80% (P < 0.001) with either AAT or rAAT. In mouse pancreatic islet macrophages, LPS-induced surface expression of MHC II, Toll-like receptor-2 and -4 were markedly lower (80%, P < 0.001) when exposed to either AAT or rAAT. Consistently, in vivo and in vitro, rAAT reduced inflammatory responses at concentrations 40-to 100-fold lower than native plasma-derived AAT. These data provide evidence that the anti-inflammatory and immunomodulatory properties of AAT can be independent of elastase inhibition.is the prototypic member of the serpin superfamily and one of the most abundant serine protease inhibitors in the circulation (1). As an acute-phase protein, AAT is thought to play an important role in limiting host-tissue injury triggered by proteases, particularly neutrophil elastase (NE). The clinical relevance of AAT is highlighted in individuals with inherited deficiency in circulating AAT, who have increased susceptibility to early-onset pulmonary emphysema, liver and pancreatic diseases, and in rare cases to panniculitis and vasculitis (2). It has been assumed that in AAT-deficiency the protease/antiprotease balance is shifted toward NE, which leads to extensive tissue damage, particularly in causing emphysema. Therefore, augmentation of circulating AAT was introduced 25 y ago to treat emphysema patients with severe PiZZ (Glu342Lys) AAT deficiency (3). Because clinical trials of AAT augmentation therapy use historical data as controls, the benefit of AAT therapy for PiZZ patients remains under debate (4-6), although in most cases therapy offers disease stabilization. The uncertainty surrounding the efficacy of augmentation therapy also reflects the incomplete understanding of the properties of the AAT protein, which can be affected by the isolation methods from plasma.Although the a...
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