Klaus Aumayr
Medical University of Vienna
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Featured researches published by Klaus Aumayr.
Annals of Surgery | 2004
Sebastian F. Schoppmann; Guenther Bayer; Klaus Aumayr; Susanne Taucher; Silvana Geleff; Margaretha Rudas; E. Kubista; Hubert Hausmaninger; Hellmut Samonigg; Michael Gnant; Raimund Jakesz; Reinhard Horvat
Objective:The aim of this study was to investigate the prognostic relevance of lymphangiogenesis and lymphovascular invasion in a large cohort of breast cancer patients. Introduction:Invasion of tumor cells into blood and lymphatic vessels is one of the critical steps for metastasis. The presence or absence of lymph node metastasis is one of the main decision criteria for further therapy. One shortcoming of previous morphologic studies was the lack of specific markers that could exact discriminate between blood and lymphatic vessels. The aim of this study was to evaluate the prognostic relevance of lymphangiogenesis and lymphovascular invasion in breast cancer patients. Methods:We investigated 374 tissue specimens of patients suffering from invasive breast cancer by immunostaining for the lymphatic endothelial specific marker podoplanin. Lymphangiogenesis, quantified by evaluating the lymphatic microvessels density (LMVD), and lymphovascular invasion (LVI) were correlated with various clinical parameters and prognostic relevance. Results:LMVD correlated significantly with LVI (P = 0.001). LVI was associated significantly with a higher risk for developing lymph-node metastasis (P = 0.004). Calculating the prognostic relevance, LVI presented as an independent prognostic parameter for disease free as well as overall survival (P = 0.001, and P = 0.001, respectively). Conclusion:Our data provide evidence that the biologic system of lymphangiogenesis constitutes a potential new target for development of anti-breast cancer therapeutic concepts. Our results further suggest that young, premenopausal patients with low differentiated breast tumors and high LMVD and LVI would, in particular, benefit from lymphangiogenesis-associated therapeutic strategies.
International Journal of Cancer | 2003
Sebastian F. Schoppmann; Monika Schindl; Guenther Bayer; Klaus Aumayr; Julia Dienes; Reinhard Horvat; Margaretha Rudas; Michael Gnant; Raimund Jakesz; Peter Birner
Id‐1 is an important regulator of cellular growth and differentiation and controls malignant progression of breast cancer cells. The aim of our study was to assess the clinical impact of Id‐1 expression in breast cancer, i.e., its potential impact on prognosis and prediction of treatment response. Id‐1 protein expression was determined immunohistochemically in 191 patients with lymph‐node negative breast cancer, and univariate and multivariate survival analysis was carried out. Fifteen (7.9%) specimens showed strong expression, 75 (39.3%) moderate, 55 (28.8%) weak expression and 46 (24.1%) cases no expression of Id‐1. Patients with strong or moderate Id‐1 expression had a significant shorter overall (p = 0.003, Cox regression) and disease‐free survival (p = 0.01, Cox regression) compared to those with absent or low expression. Progesterone receptor density was significantly higher in breast cancers with absent/low Id‐1 expression compared to those with moderate/strong expression (p < 0.001, t‐test). Id‐1 expression was significantly stronger in cases positive for p16INK4a expression compared to those negative for p16 (p = 0.049, Mann‐Whitney test). The influence of Id‐1 on clinical outcome seems much stronger in patients with negative estrogen receptor status compared to those with positive status, who received receptor antagonists as adjuvant therapy in most cases. Overexpression of Id‐1 protein represents a strong independent prognostic marker in node negative breast cancer, and future therapies inhibiting Id‐1 expression might be beneficial for these patients. Our results also suggest that due to the apparent interaction of Id‐1 with the steroid‐receptor system in breast cancer, hormonal therapies might influence Id‐1 expression and its impact on clinical outcome.
Journal of Heart and Lung Transplantation | 2014
Nina Pilat; Andreas M. Farkas; Benedikt Mahr; Christoph Schwarz; Lukas Unger; Karin Hock; Rupert Oberhuber; Klaus Aumayr; Fritz Wrba; Thomas Wekerle
Background The mixed chimerism approach induces donor-specific tolerance in both pre-clinical models and clinical pilot trials. However, chronic rejection of heart allografts and acute rejection of skin allografts were observed in some chimeric animals despite persistent hematopoietic chimerism and tolerance toward donor antigens in vitro. We tested whether additional cell therapy with regulatory T cells (Tregs) is able to induce full immunologic tolerance and prevent chronic rejection. Methods We recently developed a murine “Treg bone marrow (BM) transplantation (BMT) protocol” that is devoid of cytoreductive recipient pre-treatment. The protocol consists of a moderate dose of fully mismatched allogeneic donor BM under costimulation blockade, together with polyclonal recipient Tregs and rapamycin. Control groups received BMT under non-myeloablative irradiation and costimulation blockade without Treg therapy. Multilineage chimerism was followed by flow cytometry, and tolerance was assessed by donor-specific skin and heart allografts. Results Durable multilineage chimerism and long-term donor skin and heart allograft survival were successfully achieved with both protocols. Notably, histologic examination of heart allografts at the end of follow-up revealed that chronic rejection is prevented only in chimeras induced with the Treg protocol. Conclusions In a mouse model of mixed chimerism, additional Treg treatment at the time of BMT prevents chronic rejection of heart allografts. As the Treg-chimerism protocol also obviates the need for cytoreductive recipient treatment it improves both efficacy and safety over previous non-myeloablative mixed chimerism regimens. These results may significantly impact the development of protocols for tolerance induction in cardiac transplantation.
Applied Immunohistochemistry & Molecular Morphology | 2014
Klaus Aumayr; Afschin Soleiman; Klaus Sahora; Martin Schindl; Gregor Werba; Sebastian F. Schoppmann; Peter Birner
Background:Despite advances in combination therapies, the prognosis of pancreatic ductal adenocarcinoma (PDAC) remains extremely poor. Blocking of overexpressed HER2 oncogene improves survival in breast and gastroesophageal cancer and might be also a therapeutic option in PDAC. The purpose of this study was to evaluate HER2 gene amplification and protein expression in PDAC. Methods:HER2 protein expression was investigated using a FDA-approved antibody in 87 formalin-fixed and paraffin-embedded cases of PDAC with complete follow-up. HER2 gene amplification was assessed on tissue microarrays using dual color silver in situ hybridization (DISH). Results:Generally, HER2 immunostaining showed considerable heterogeneity. In 19 cases, ≥10 of tumor cells showed some positive reaction. In no case, complete membranous staining was observed. Using the scoring system developed for assessment of HER2 status in gastroesophageal cancer, 9 cases showed positive immunohistologic staining (score 2+ to 3+). After performing DISH, 6 (7%) immunohistochemically 2+ or 3+ cases were found to have HER2 gene amplification, whereas none of these cases showed polyploidy. No association of HER2 status and clinicopathologic parameters or survival was observed (P>0.05). Conclusions:HER2 is overexpressed in a subset of PDACs, identifying them as possible candidates for a targeted therapy. For assessment of HER2 status in PDAC, the scoring system originally developed for gastric cancer is recommend.
Experimental Dermatology | 2013
Johanna Eder; Franco Laccone; Marianne Rohrbach; Cecilia Giunta; Klaus Aumayr; Christofer Reichel; Franz Trautinger
The vascular type of the Ehlers–Danlos syndrome (Ehlers–Danlos syndrome type IV, EDS IV; OMIM #130050) is a rare connective tissue disorder with autosomal dominant transmission caused by mutations in the COL3A1 gene resulting in increased fragility of connective tissue with arterial, intestinal, and uterine ruptures and premature death. We present a 28‐year‐old female who in addition to typical EDS IV symptoms had severe peripheral artery occlusive disease (PAOD) and subtotal stenosis of the abdominal aorta. COL3A1 sequencing resulted in detection of an as yet undescribed mutation in exon 36 at position 2465 leading to a nucleotide replacement (c.2465G>C; p.G822A). Ultrastructural analysis of a skin biopsy revealed abnormal morphology and distribution of dermal collagen fibres. We conclude that PAOD is a possible manifestation of EDS IV and that further research is required to define its true prevalence among patients with EDS IV and its molecular pathology including genotype–phenotype correlation.
American Journal of Transplantation | 2016
Christoph Schwarz; Lukas Unger; Benedikt Mahr; Klaus Aumayr; Heinz Regele; Andreas M. Farkas; Karin Hock; Nina Pilat; Thomas Wekerle
B7.1/2‐targeted costimulation blockade (CTLA4 immunoglobulin [CTLA4‐Ig]) is available for immunosuppression after kidney transplantation, but its potentially detrimental impact on regulatory T cells (Tregs) is of concern. We investigated the effects of CTLA4‐Ig monotherapy in a fully mismatched heart transplant model (BALB/c onto C57BL/6). CTLA4‐Ig was injected chronically (on days 0, 4, 14, and 28 and every 4 weeks thereafter) in dosing regimens paralleling clinical use, shown per mouse: low dose (LD), 0.25 mg (≈10 mg/kg body weight); high dose (HD), 1.25 mg (≈50 mg/kg body weight); and very high dose (VHD), 6.25 mg (≈250 mg/kg body weight). Chronic CTLA4‐Ig therapy showed dose‐dependent efficacy, with the LD regimen prolonging graft survival and with the HD and VHD regimens leading to >95% long‐term graft survival and preserved histology. CTLA4‐Igs effect was immunosuppressive rather than tolerogenic because treatment cessation after ≈3 mo led to rejection. FoxP3‐positive Tregs were reduced in naïve mice to a similar degree, independent of the CTLA4‐Ig dose, but recovered to normal values in heart recipients under chronic CTLA4‐Ig therapy. Treg depletion (anti‐CD25) resulted in an impaired outcome under LD therapy but had no detectable effect under HD therapy. Consequently, the immunosuppressive effect of partially effective LD CTLA4‐Ig therapy is impaired when Tregs are removed, whereas CTLA4‐Ig monotherapy at higher doses effectively maintains graft survival independent of Tregs.
Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2015
Claudia Lill; Sven Schneider; Rudolf Seemann; Lorenz Kadletz; Klaus Aumayr; Bahil Ghanim; Dietmar Thurnher
Malignant tumors of the salivary glands comprise about 3% to 5% of all head and neck carcinomas. The purpose of our study was to find possible predictive and/or prognostic markers for parotid cancer.
PLOS ONE | 2013
Barbara Messner; Johann Kern; Dominik Wiedemann; Stefan Schwaiger; Adrian Türkcan; Christian Ploner; Alexander Trockenbacher; Klaus Aumayr; Nikolaos Bonaros; Günther Laufer; Hermann Stuppner; Gerold Untergasser; David Bernhard
Background Insufficient angiogenesis and arteriogenesis in cardiac tissue after myocardial infarction (MI) is a significant factor hampering the functional recovery of the heart. To overcome this problem we screened for compounds capable of stimulating angiogenesis, and herein investigate the most active molecule, 5-Methoxyleoligin (5ML), in detail. Methods and Results 5ML potently stimulated endothelial tube formation, angiogenic sprouting, and angiogenesis in a chicken chorioallantoic membrane assay. Further, microarray- and knock down- based analyses revealed that 5ML induces angiogenesis by upregulation of CYP26B1. In an in vivo rat MI model 5ML potently increased the number of arterioles in the peri-infarction and infarction area, reduced myocardial muscle loss, and led to a significant increase in LV function (plus 21% 28 days after MI). Conclusion The present study shows that 5ML induces CYP26B1-dependent angiogenesis in vitro, and arteriogenesis in vivo. Whether or not CYP26B1 is relevant for in vivo arteriogenesis is not clear at the moment. Importantly, 5ML-induced arteriogenesis in vivo makes the compound even more interesting for a post MI therapy. 5ML may constitute the first low molecular weight compound leading to an improvement of myocardial function after MI.
Apmis | 2014
Oskar Koperek; Klaus Aumayr; Martin Schindl; Gregor Werba; Afschin Soleiman; Sebastian F. Schoppmann; Klaus Sahora; Peter Birner
Activation of signal‐transcriptional factor signal transducer and activator of transcription 3 (STAT3) is associated with more aggressive behaviour in a variety of human malignancies. As selective STAT3 inhibitors exist, this protein might represent a novel therapeutic target. Although STAT3 seems to play an important role in progression of pancreatic ductal carcinoma (PDAC), only few data on this subject exist. The aim of our study was the investigation of STAT3 activation and its correlation with its possible regulator HER2. Expression of tyrosine‐705 phosphorylated STAT3 (pSTAT3) was determined immunohistochemically in 79 PDACs. HER2 status assessed by immunohistochemistry and double colour silver in situ hybridization was available from a previous study. PSTAT3 expression was seen in 33 (41.8%) patients. Six patients were scored as HER2 positive having strong correlation with pSTAT3 expression (p = 0.004, Fisher′s exact test). No association of pSTAT3 expression with patients′ age, tumour staging and grading, perineural invasion of tumour cells or survival time was seen. pSTAT3 is frequently expressed in PDAC. Nevertheless, its immediate clinical relevance seems to be low. However, further research needs to determine whether STAT3 status in PDAC is predictive for the response to novel targeting therapies.
The Prostate | 2011
Klaus Aumayr; Michael Breitegger; Peter R. Mazal; Anke Koller; M. Marberger; Martin Susani; Andrea Haitel
The prognostic relevance of the amount of extraprostatic cancer spread in nerves in prostate cancer patients is not well established.