Publications by authors named "Alexander Hauswirth"

43 Publications

Functional Precision Medicine Provides Clinical Benefit in Advanced Aggressive Hematological Cancers and Identifies Exceptional Responders.

Cancer Discov 2021 Oct 11. Epub 2021 Oct 11.

Platform Austria for Chemical Biology, CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences.

Personalized medicine aims to match the right drug with the right patient by utilizing specific features of the individual patients' tumor. However, current strategies of personalized therapy matching only provide treatment opportunities for less than 10% of cancer patients. A promising method may be drug profiling of patient biopsies with single-cell resolution to directly quantify drug effects. We prospectively tested an image-based single-cell functional precision medicine (scFPM) approach to guide treatments in 143 patients with advanced aggressive hematologic cancers. Fifty-six patients (39%) were treated according to scFPM results. At a median follow-up of 23.9 months, 30 patients (54%) demonstrated a clinical benefit of more than 1.3-fold enhanced progression-free survival (PFS) compared to their previous therapy. Twelve patients (40% of responders) experienced exceptional responses lasting three times longer than expected for their respective disease. We conclude, that therapy matching by scFPM is clinically feasible, and effective in advanced aggressive hematologic cancers.
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http://dx.doi.org/10.1158/2159-8290.CD-21-0538DOI Listing
October 2021

Successful treatment of vaccine-induced prothrombotic immune thrombocytopenia (VIPIT).

J Thromb Haemost 2021 07 11;19(7):1819-1822. Epub 2021 Jun 11.

Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.

Cases of unusual thrombosis and thrombocytopenia after administration of the ChAdOx1 nCoV-19 vaccine (AstraZeneca) have been reported. The term vaccine-induced prothrombotic immune thrombocytopenia (VIPIT) was coined to reflect this new phenomenon. In vitro experiments with VIPIT patient sera indicated that high-dose intravenous immunoglobulins (IVIG) competitively inhibit the platelet-activating properties of ChAdOx1 nCoV-19 vaccine induced antibodies. Here, we report a case of a 62-year-old woman who had received this vaccine and developed VIPIT. She visited the emergency ward because of petechiae and hematomas. In the laboratory work-up, thrombocytopenia, low fibrinogen, elevated D-dimer, and positivity in the platelet factor 4/heparin-enzyme-immunoassay were present. Signs and symptoms of thrombosis were absent. Upon immediate therapy with non-heparin anticoagulation, high-dose IVIG, and prednisolone, laboratory parameters steadily improved and the patient was discharged from hospital without thrombotic complications. We conclude that early initiation of VIPIT treatment results in a swift response without thrombotic complications.
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http://dx.doi.org/10.1111/jth.15346DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8362082PMC
July 2021

Phenotyping and Target Expression Profiling of CD34/CD38 and CD34/CD38 Stem- and Progenitor cells in Acute Lymphoblastic Leukemia.

Neoplasia 2018 06 15;20(6):632-642. Epub 2018 May 15.

Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria. Electronic address:

Leukemic stem cells (LSCs) are an emerging target of curative anti-leukemia therapy. In acute lymphoblastic leukemia (ALL), LSCs frequently express CD34 and often lack CD38. However, little is known about markers and targets expressed in ALL LSCs. We have examined marker- and target expression profiles in CD34/CD38 LSCs in patients with Ph ALL (n = 22) and Ph ALL (n = 27) by multi-color flow cytometry and qPCR. ALL LSCs expressed CD19 (B4), CD44 (Pgp-1), CD123 (IL-3RA), and CD184 (CXCR4) in all patients tested. Moreover, in various subgroups of patients, LSCs also displayed CD20 (MS4A1) (10/41 = 24%), CD22 (12/20 = 60%), CD33 (Siglec-3) (20/48 = 42%), CD52 (CAMPATH-1) (17/40 = 43%), IL-1RAP (13/29 = 45%), and/or CD135 (FLT3) (4/20 = 20%). CD25 (IL-2RA) and CD26 (DPPIV) were expressed on LSCs in Ph ALL exhibiting BCR/ABL1, whereas in Ph ALL with BCR/ABL1, LSCs variably expressed CD25 but did not express CD26. In Ph ALL, CD34/CD38 LSCs expressed IL-1RAP in 6/18 patients (33%), but did not express CD25 or CD26. Normal stem cells stained negative for CD25, CD26 and IL-1RAP, and expressed only low amounts of CD52. In xenotransplantation experiments, CD34/CD38 and CD34/CD38 cells engrafted NSG mice after 12-20 weeks, and targeting with antibodies against CD33 and CD52 resulted in reduced engraftment. Together, LSCs in Ph and Ph ALL display unique marker- and target expression profiles. In Ph ALL with BCR/ABL1, the LSC-phenotype closely resembles the marker-profile of CD34/CD38 LSCs in chronic myeloid leukemia, confirming the close biologic relationship of these neoplasms. Targeting of LSCs with specific antibodies or related immunotherapies may facilitate LSC eradication in ALL.
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http://dx.doi.org/10.1016/j.neo.2018.04.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5994777PMC
June 2018

The pan-BCL-2-blocker obatoclax (GX15-070) and the PI3-kinase/mTOR-inhibitor BEZ235 produce cooperative growth-inhibitory effects in ALL cells.

Oncotarget 2017 Sep 28;8(40):67709-67722. Epub 2017 Jun 28.

Department of Internal Medicine I, Division of Hematology & Hemostaseology, Medical University of Vienna, Vienna, Austria.

Acute lymphoblastic leukemia (ALL) is characterized by leukemic expansion of lymphoid blasts in hematopoietic tissues. Despite improved therapy only a subset of patients can be cured. Therefore, current research is focusing on new drug-targets. Members of the BCL-2 family and components of the PI3-kinase/mTOR pathway are critically involved in the regulation of growth and survival of ALL cells. We examined the effects of the pan-BCL-2 blocker obatoclax and the PI3-kinase/mTOR-inhibitor BEZ235 on growth and survival of ALL cells. In H-thymidine uptake experiments, both drugs suppressed the proliferation of leukemic cells in all patients with Philadelphia chromosome-positive (Ph) ALL and Ph ALL (obatoclax IC: 0.01-5 μM; BEZ235, IC: 0.01-1 μM). Both drugs were also found to produce growth-inhibitory effects in all Ph and all Ph cell lines tested. Moreover, obatoclax and BEZ235 induced apoptosis in ALL cells. In drug-combination experiments, obatoclax and BEZ235 exerted synergistic growth-inhibitory effects on ALL cells. Finally, we confirmed that ALL cells, including CD34/CD38 stem cells and all cell lines express transcripts for PI3-kinase, mTOR, BCL-2, MCL-1, and BCL-xL. Taken together, this data shows that combined targeting of the PI3-kinase/mTOR-pathway and BCL-2 family-members is a potent approach to counteract growth and survival of ALL cells.
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http://dx.doi.org/10.18632/oncotarget.18810DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5620205PMC
September 2017

First-in-human response of BCL-2 inhibitor venetoclax in T-cell prolymphocytic leukemia.

Blood 2017 12 27;130(23):2499-2503. Epub 2017 Sep 27.

Division of Hematology and Hemostaseology, Department of Internal Medicine I.

T-cell prolymphocytic leukemia (T-PLL) is a rare and aggressive T-lymphoid malignancy usually refractory to current treatment strategies and associated with short overall survival. By applying next-generation functional testing of primary patient-derived lymphoma cells using a library of 106 US Food and Drug Administration (FDA)-approved anticancer drugs or compounds currently in clinical development, we set out to identify novel effective treatments for T-PLL patients. We found that the B-cell lymphoma 2 (BCL-2) inhibitor venetoclax (ABT-199) demonstrated the strongest T-PLL-specific response when comparing individual ex vivo drug response in 86 patients with refractory hematologic malignancies. Mechanistically, responses to venetoclax correlated with protein expression of BCL-2 but not with expression of the BCL-2 family members myeloid cell leukemia 1 (MCL-1) and BCL-XL in lymphoma cells. BCL-2 expression was inversely correlated with the expression of MCL-1. Based on the ex vivo responses, venetoclax treatment was commenced in 2 late-stage refractory T-PLL patients resulting in clinical responses. Our findings demonstrate first evidence of single-agent activity of venetoclax both ex vivo and in humans, offering a novel agent in T-PLL.
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http://dx.doi.org/10.1182/blood-2017-05-785683DOI Listing
December 2017

Incidence of intensive care unit admission, outcome and post intensive care survival in patients with diffuse large B-cell lymphoma.

Leuk Lymphoma 2016 08 13;57(8):1831-8. Epub 2016 Jan 13.

a Department of Medicine I, Intensive Care Unit 13i2 , Medical University of Vienna , Vienna , Austria ;

Some patients with diffuse large B-cell lymphoma (DLBCL) require intensive care unit (ICU) admission prior to or during chemotherapy. We analyzed all unscheduled ICU admissions in 331 consecutive patients (18-93 years) with newly diagnosed DLBCL. Thirty-seven patients (11.2%) required ICU treatment primarily due to hemodynamic (37.8%) or respiratory failure (24.3%). Bulky disease and high IPI score were predictive of ICU admission in the early course. ICU and hospital survival was 75.7% and 70.3%, respectively. Overall survival in ICU patients with newly diagnosed DLBCL was worse compared to non-ICU-patients (40.7% vs. 72.7% at two years). However, survival of high-risk patients (IPI 3-5), continuous complete remission, and disease-free survival did not differ. Post-ICU survival was poor in patients with relapsed/refractory DLBCL (0.1-10 months). Our observations favor unrestricted ICU support in DLBCL patients undergoing first-line therapy. ICU referral of patients with refractory/relapsed disease must be evaluated in the context of the hematologic prognosis.
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http://dx.doi.org/10.3109/10428194.2015.1106537DOI Listing
August 2016

Clofarabine/cyclophosphamide for debulking before stem cell transplantation.

Eur J Clin Invest 2014 Aug;44(8):775-83

Bone Marrow Transplantation Unit, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria; Intensive Care Unit, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria.

Background: Allogeneic haematopoietic stem cell transplantation (HSCT) is the only curative rescue therapy for patients (pts) with chemotherapy-refractory acute leukaemia. Disease control prior to HSCT is essential for long-term disease-free survival after HSCT.

Patients And Methods: We have retrospectively analysed the outcome of 20 pts aged 21-64 years with refractory leukaemia (acute myeloid leukaemia, n = 16; acute lymphatic leukaemia, n = 4) who received debulking therapy with clofarabine (10 mg/m², days 1-4) and cyclophosphamide (200 mg/m², days 1-4; ClofCy) prior to HSCT.

Results: Clofarabine/cyclophosphamide (1-4 cycles) was well tolerated and resulted in a substantial reduction of leukaemic cells in all pts. HSCT was performed in 15 of 20 pts. After HSCT (myeloablative, n = 9; dose-reduced, n = 6), all pts showed engraftment and full donor chimerism (related donors, n = 4 or unrelated donors, n = 11) and all pts achieved complete haematologic remission (CR). The median survival after HSCT is 531 days (range: 48-1462 days), and six pts are still alive after a median of 1245 days. Seven pts died after they had relapsed between days +152 and +1496. One patient died from acute graft-versus-host disease (day +48) and one from systemic fungal infection (day +87).

Conclusion: Clofarabine/cyclophosphamide is a novel effective treatment approach for pts with chemotherapy-refractory acute leukaemia prior to HSCT. Whether this novel debulking protocol leads to improved long-term outcome in pts with refractory leukaemias remains to be determined in forthcoming clinical studies.
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http://dx.doi.org/10.1111/eci.12294DOI Listing
August 2014

Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.

Am J Hematol 2012 Jul 8;87(7):721-4. Epub 2012 Jun 8.

Instituto de Biologia Molecular y Celular del Cancer, Centro de Investigacion del Cancer/IBMCC, University of Salamanca, Salamanca, Spain.

Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.Little is known about the distribution of normal lymphoid cells and their subsets in the peripheral blood (PB) of subjects with monoclonal B-cell lymphocytosis (MBL). In our study, we compared the absolute number of PB lymphoid cells and their subpopulations in 95 MBL cases with normal lymphocyte counts vs. 617 age-/sex-matched non-MBL healthy subjects (controls), using highly sensitive flow cytometry. MBL cases showed significantly reduced numbers of normal circulating B-cells, at the expense of immature and naive B-cells; in addition, CD4+CD8+ double-positive T-cells and CD8+ T-cells were significantly lower and higher vs. controls, respectively. Moreover, most normal B-cell subsets were significantly decreased in PB at >1% MBL-counts, vs. "low-count" MBL cases, and lower amounts of immature/naive B-cells were detected in biclonal (particularly in cases with coexisting CLL-like- and non-CLL-like B-cell clones) vs. monoclonal MBL subjects. In summary, our results show imbalanced (reduced) absolute numbers of recently produced normal circulating B-cells (e.g., immature and naıve B-cells) in MBL, which becomes more pronounced as the MBL cell count increases.
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http://dx.doi.org/10.1002/ajh.23214DOI Listing
July 2012

Prolonged progression-free survival in patients with chronic lymphocytic leukemia receiving granulocyte colony-stimulating factor during treatment with fludarabine, cyclophosphamide, and rituximab.

Ann Hematol 2011 Oct 27;90(10):1131-6. Epub 2011 May 27.

Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Währinger Gürtel 18-20, Vienna, Austria.

The clinical benefit of the addition of granulocyte colony-stimulating factor (G-CSF) to standard immunochemotherapy of chronic lymphocytic leukemia (CLL) with fludarabine, cyclophosphamide, and rituximab (FCR) is still unclear. In this retrospective study we analyzed the outcome of 32 consecutive patients with CLL during treatment with FCR. Sixteen patients received G-CSF for treatment of CTC grade 3 or 4 neutropenia or febrile neutropenia at some point during therapy and 16 did not. Both groups were well balanced for clinical and biological risk factors. Overall response rates were not significantly different (94% vs. 75%; p=0.144). Interestingly, a significantly better progression-free survival (100% vs. 35.4% at 24 months; p<0.001) and even overall survival (100% vs. 77.8% at 24 months; p=0.022) was observed in patients receiving G-CSF. While the underlying cause remains to be elucidated, these data strongly suggest an association of the addition of G-CSF to FCR therapy with final patient outcome.
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http://dx.doi.org/10.1007/s00277-011-1260-xDOI Listing
October 2011

Stable non-transforming minimal residual disease in Philadelphia chromosome positive acute lymphoblastic leukemia after autologous transplantation: origin from neoplastic yet 'pre-leukemic' stem cells?

Leuk Lymphoma 2011 May 4;52(5):842-8. Epub 2011 Apr 4.

Bone Marrow Transplantation Unit, Department of Internal Medicine I, Medical University of Vienna, Austria.

In acute lymphoblastic leukemia (ALL), the Philadelphia chromosome (Ph) is associated with a poor prognosis. For these patients, hematopoietic stem cell transplantation (HSCT) and BCR/ABL tyrosine kinase inhibitors (TKIs) are considered standard of therapy. However, it remains unclear whether BCR/ABL TKIs should be administered lifelong as maintenance post-HSCT, and whether the presence of minimal residual disease (MRD) is invariably associated with relapse. We report on two patients with Ph+ ALL who were successfully treated with polychemotherapy and consecutive autologous HSCT. Both patients are in continuous hematologic remission after an observation period of 12 years and 18 years, respectively, despite measurable MRD and although no maintenance therapy was initiated. BCR/ABL transcript-levels ranged between 0.1 and 3% in patient 1, and 0.01 and 0.1% in patient 2 during the observation time. Collectively, these data suggest that not all Ph+ subclones even those that persist after HSCT in Ph+ ALL, may have the potential to cause a hematologic relapse. We hypothesize that these small-sized clones are derived from neoplastic stem cells that have not (yet) accumulated a sufficient number of pro-oncogenic hits required for full transformation to ALL-initiating (stem) cells and thus overt leukemia.
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http://dx.doi.org/10.3109/10428194.2011.557168DOI Listing
May 2011

Prevalence and clinical impact of autoimmune diseases and chronic infections in malignant lymphomas at diagnosis.

Ann Hematol 2011 Aug 17;90(8):947-54. Epub 2011 Feb 17.

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Comprehensive Cancer Center (CCC), Medical University of Vienna, Vienna, Austria.

There is increasing evidence for the role of chronic antigenic stimulation (CS) in the development of cancer. Clinical data, however, are rare as is the information on outcome. In this study, the occurrence of chronic infections (CI) and autoimmune diseases (AI) in patients with malignant lymphoma at diagnosis was assessed. Of 367 patients [non-Hodgkin's lymphoma (NHL) N = 297, Hodgkin's lymphoma N = 70], 9.8% (N = 36) had a history of chronic antigenic stimulation (4.4% AI, 5.4% CI) at diagnosis. After a median observation time of 74.7 months, 118 patients have died. There were more male patients in this cohort. However, sex ratio among patients with chronic antigenic stimulation was skewed in favor of women (p = 0.018), in particular among lymphoma patients with AI (p = 0.001). NHL patients with autoimmune diseases showed a tendency to develop diffuse large B cell lymphoma [8 of 12 AI + NHL patients (66.7%) vs. 100 of 266 non-CS NHL (37.6%); p = 0.066]. No significant difference in overall survival (OS) between CS and non-CS patients could be observed (median OS after 48 months was: CS 77.7% vs. non-CS 71.8%). In conclusion, chronic antigenic stimulation at diagnosis appears to be associated with a higher prevalence in women, in particular among patients with autoimmune disease. However, no difference in overall survival was observed. This suggests that the presence of chronic inflammatory conditions does not decisively influence the outcome of lymphoma patients.
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http://dx.doi.org/10.1007/s00277-011-1178-3DOI Listing
August 2011

Nonpegylated liposomal doxorubicin is highly active in patients with B and T/NK cell lymphomas with cardiac comorbidity or higher age.

Ann Hematol 2010 Feb 28;89(2):163-9. Epub 2009 Jul 28.

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.

We used nonpegylated liposomal doxorubicin (NPLD) in cytostatic drug combinations to treat 37 patients with non-Hodgkin's lymphoma and pre-existing cardiac disorder or elderly patients with reduced physical state who were ineligible for conventional anthracycline-containing therapy. High remission rates were observed in this poor-risk population: Complete remission rates were 75% for diffuse large B cell lymphoma (DLBCL) and 55% for T/NK cell neoplasm (overall response rate of 80% and 89%, respectively). Twenty-seven patients (73%) are still alive after a median observation time of 14 months. No major cardiac or gastrointestinal toxicity was observed. Extravasation of NPLD in two patients resulted in mild inflammation without tissue damage. Hematologic toxicity was comparable to that of conventional anthracycline-containing regimens. We conclude that NPLD is highly active in combination chemotherapy for lymphoma with low cardiac toxicity in patients with pre-existing cardiac disorders or higher age. Moreover, we also observed remarkable efficacy in T/NK cell lymphomas.
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http://dx.doi.org/10.1007/s00277-009-0796-5DOI Listing
February 2010

Autoimmune conditions and chronic infections in chronic lymphocytic leukemia patients at diagnosis are associated with unmutated IgVH genes.

Haematologica 2008 Dec 6;93(12):1912-6. Epub 2008 Oct 6.

Division of Haematology & Haemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria.

Few data are available concerning the prevalence of autoimmune disease or chronic infections in chronic lymphocytic leukemia patients at diagnosis as well as their clinical outcome. We studied the frequency of such chronic conditions in relation to prognostic markers. A history of autoimmune disease or chronic infection was found in 21% of 186 chronic lymphocytic leukemia patients (12% in autoimmune diseases, 9% in chronic infections). Patients with a history of chronic stimulation were more likely to have unmutated IgV(H) genes (p<0.002), unfavorable or intermediate risk cytogenetics (11q, 17p deletions, trisomy 12) (p<0.001), and higher CD38 expression (p=0.004). Autoimmune conditions (n=22) were characterized by female predominance (55.0%) with a high frequency of unmutated IgV(H) (53,8%). Median time to first treatment was 83 months for the chronic stimulation group compared to 128 months for the non-chronic stimulation group (n.s.). Patients suffering from chronic conditions at chronic lymphocytic leukemia diagnosis are likely to have poor prognostic markers, particularly unmutated IgV(H) genes.
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http://dx.doi.org/10.3324/haematol.12955DOI Listing
December 2008

Disruption of allergenic activity of the major grass pollen allergen Phl p 2 by reassembly as a mosaic protein.

J Immunol 2008 Oct;181(7):4864-73

Division of Immunopathology, Department of Pathophysiology, Center of Physiology, Pathophysiology and Immunology, Vienna General Hospital, Medical University of Vienna, Vienna, Austria.

The recognition of conformational epitopes on respiratory allergens by IgE Abs is a key event in allergic inflammation. We report a molecular strategy for the conversion of allergens into vaccines with reduced allergenic activity, which is based on the reassembly of non-IgE-reactive fragments in the form of mosaic proteins. This evolution process is exemplified for timothy grass pollen-derived Phl p 2, a major allergen for more than 200 million allergic patients. In a first step, the allergen was disrupted into peptide fragments lacking IgE reactivity. cDNAs coding for these peptides were reassembled in altered order and expressed as a recombinant mosaic molecule. The mosaic molecule had lost the three-dimensional structure, the IgE reactivity, and allergenic activity of the wild-type allergen, but it induced high levels of allergen-specific IgG Abs upon immunization. These IgG Abs crossreacted with group 2 allergens from other grass species and inhibited allergic patients' IgE binding to the wild-type allergen. The mosaic strategy is a general strategy for the reduction of allergenic activity of protein allergens and can be used to convert harmful allergens into safe vaccines.
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http://dx.doi.org/10.4049/jimmunol.181.7.4864DOI Listing
October 2008

Indolent systemic mastocytosis associated with atypical small lymphocytic lymphoma: a rare form of concomitant lymphoproliferative disease.

Hum Pathol 2008 Jun 2;39(6):917-24. Epub 2008 May 2.

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, 1090 Vienna, Austria.

Patients with systemic mastocytosis (SM) may acquire an associated hematologic non-mast cell (MC)-lineage disease (AHNMD). In most cases, a myeloid neoplasm is diagnosed, whereas the occurrence of a lymphoproliferative disease is an extremely rare event. We report on a patient with indolent SM associated with small lymphocytic lymphoma (SLL). The patient presented with lymphadenopathy, maculopapular exanthema, and elevated serum tryptase. The bone marrow biopsy showed focal MC aggregates together with SLL. As assessed by immunostaining, neoplastic MC were found to exhibit CD117 and CD25 but did not display CD5 or CD20, whereas SLL cells were found to coexpress CD5 and CD20 but did not express MC antigens. The KIT mutation D816V was detected in sorted CD34(+) cells and unfractionated marrow cells but not in CD5(+) SLL cells, confirming the coexistence of 2 distinct neoplasms.
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http://dx.doi.org/10.1016/j.humpath.2007.10.022DOI Listing
June 2008

Autoimmune thrombocytopenia in non-Hodgkin's lymphomas.

Haematologica 2008 Mar 20;93(3):447-50. Epub 2008 Feb 20.

Department of Medicine I, Division of Haematology and Haemostaseology, Medical University of Vienna, Vienna, Austria.

Autoimmune thrombocytopenia is a common immunehematologic complication in non-Hodgkin's lymphomas and may complicate the treatment. We analyzed an original series from our institute as well as published cases of non-Hodgkin's lymphomas (excluding chronic lymphocytic leukemia) associated with autoimmune thrombocytopenia with regard to demographic factors, prevalence in non-Hodgkin's lymphoma subtypes and treatment outcome. The male/female ratio is 1.75. Half of the cases occurred prior to diagnosis of lymphoma. Chemotherapy is the best treatment in many non-Hodgkin's lymphomas patients with autoimmune thrombocytopenia compared with standard treatment of autoimmune thrombocytopenia. Splenectomy is effective in splenic marginal zone lymphoma. Autoimmune thrombocytopenia in patients with non-Hodgkin's lymphomas is potentially life-threatening and difficult to treat.
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http://dx.doi.org/10.3324/haematol.11934DOI Listing
March 2008

Prognostic value of T-cell receptor gamma rearrangement in peripheral blood or bone marrow of patients with peripheral T-cell lymphomas.

Leuk Lymphoma 2008 Feb;49(2):237-46

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, A-1090 Vienna, Austria.

Peripheral T-cell lymphomas (PTCL) have a variable outcome. We have investigated the prognostic value of molecular staging in non-anaplastic PTCL. T-cell receptor gamma rearrangements were routinely determined in peripheral blood (n = 40) and bone marrow (n = 38) of patients with PTCL (75% unspecified) by conventional PCR at diagnosis. Tissue controls for PCR included 24 tumour biopsies. Twenty-four patients (60%) had a PCR-detectable clonal TCR gamma rearrangement in PB or BM. These TCR gamma PCR positive patients had significantly more stage IV disease (14 patients of 15 patients; P = 0.001), elevated LDH (14 of 18 patients; P = 0.04), higher IPI (16 of 21 patients; P = 0.03), more anemia (15 of 19 patients; P = 0.02) and lower platelet counts (seven of seven patients; P = 0.02). Clinical outcome of this clonal group was characterised by lower complete remission rates (37.5% vs. 62.5%), and overall response rates (58.3% vs. 87.5%; P < 0.05) as well as a significantly shorter median overall survival (12.8 vs. 30.0 months; P = 0.006). Patients with clinical stages I - III but molecular stage IV had an equally poor overall survival when compared with patients with clinical stage IV (15.8 vs. 13.9 months). In contrast, patients with CS I - III in the absence of a TCR gamma rearrangement in PB or BM had a favourable outcome with an estimated overall survival of 70% at 3 and 5 years. Molecular staging in PB and BM by TCR gamma PCR at diagnosis may serve as a useful prognostic tool in PTCL.
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http://dx.doi.org/10.1080/10428190701784409DOI Listing
February 2008

Autoimmune hemolytic anemias, Evans' syndromes, and pure red cell aplasia in non-Hodgkin lymphomas.

Leuk Lymphoma 2007 Jun;48(6):1139-49

Division of Haematology and Haemostaseology, Department of Medicine I, Medical University of Vienna, Austria.

We analyzed 108 cases of non-CLL non-Hodgkin lymphoma (NHL) associated with autoimmune hemolytic anemia (AIHA) (+/- pure red cell aplasia (PRCA)) or Evans' syndrome. The analysis was based on cases reported in the literature, which were retrieved by means of Pubmed and Medline searches and of an original series of 121 patients with NHL as well as reference lists of papers in the field. The number of cases in various NHL subtypes was small (n = 6-25). Nevertheless, interesting and sometimes unexpected differences in sex prevalence, temporal relationship between onset of lymphoma and AIHA, stage of lymphoma, relative frequency of warm antibody-AIHA (WA-AIHA) and cold antibody (CA-AIHA), association with PRCA and response of AIHA to treatments were noted for various lymphoma entities. WA-AIHA was more frequent in B-cell lymphomas, while CA-AIHA and PRCA predominantly occurred in T-cell lymphomas. Anti-lymphoma treatment seemed to be more effective against AIHA than conventional therapy with steroids or immunoglobulin. Although generated by a literature survey, this compilation of data indicates a complex relation of lymphoma and AIHA and warrants more attention and specific studies.
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http://dx.doi.org/10.1080/10428190701385173DOI Listing
June 2007

Hemorrhagic herpes zoster.

Wien Klin Wochenschr 2007 ;119(7-8):217

Department of Medicine I, Medical University Vienna, Vienna, Austria.

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http://dx.doi.org/10.1007/s00508-006-0751-6DOI Listing
October 2007

Evaluation of biologic activity of tryptase secreted from blast cells in acute myeloid leukemia.

Leuk Lymphoma 2006 May;47(5):897-906

Department of Internal Medicine I, Division of Hematology & Hemostaseology - the Center of Excellence for Clinical and Experimental Oncology (CLEXO), Medical University of Vienna, Austria.

A number of autocrine and paracrine growth regulators are considered to be involved in the survival and proliferation of blast cells in acute myeloid leukemia (AML). We have recently shown that blast cells in a group of patients with AML produce and secrete the mitogenic enzyme tryptase. In the present study, we examined functional effects of tryptase in the context of AML. As assessed by 3H-thymidine uptake experiments, tryptase-containing serum from patients with AML as well as heparin-complexed recombinant tryptase were found to promote the proliferation of cultured bone marrow- and lung fibroblasts in a dose-dependent manner. A neutralizing antibody against human beta-tryptase was found to diminish these growth-stimulatory effects of serum-tryptase in all patients examined. Tryptase also induced the expression of mRNA for GM-CSF and SCF, two cytokines known to promote growth of AML cells, in cultured bone marrow fibroblasts. Neither recombinant tryptase nor tryptase-rich serum of AML patients, showed an effect on the growth of leukemic blast cells irrespective of the FAB category or expression of protease-activated receptor (PAR)-2, a putative molecular target of tryptase. Together, tryptase is secreted from AML blasts as a biologically active molecule that may exhibit paracrine rather than autocrine effects in AML.
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http://dx.doi.org/10.1080/10428190500513652DOI Listing
May 2006

Immunological characterization and antibacterial function of persisting granulocytes in leukemic patients receiving pulse cytosine arabinoside-consolidation chemotherapy on days 1, 3, and 5.

J Immunol 2006 Feb;176(3):1759-68

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Center of Excellence in Clinical and Experimental Oncology, Vienna, Austria.

High-dose cytosine arabinoside (HiDAC) and intermediate-dose cytosine arabinoside (IDAC) have been introduced as effective and safe consolidation chemotherapy in acute myeloid leukemia, with relatively low rates of life-threatening infections despite the high total dose of the cytostatic drug. To explore the biological background of low toxicity, we examined the numbers, immunophenotype, and functional properties of granulocytes in patients with acute myeloid leukemia receiving HiDAC or IDAC. Interestingly, the absolute numbers of neutrophils remained >500/microl until day 10 in 92 of 125 (74%) HiDAC cycles and in 106 of 113 (94%) IDAC cycles. As assessed by electron microscopy, these day-10 granulocytes surviving chemotherapy were found to be mature cells containing secondary granules and phagolysosomes. They also expressed opsonization- and phagocytosis-linked surface Ags (C3biR, CR1, C1qR, C5aR, FcgammaRI, FcgammaRII, FcgammaRIII, and G-CSF and GM-CSF receptors) like neutrophils in healthy controls. Moreover, these day-10 neutrophils exhibited oxidative burst activity and took up and digested bacteria in the same way as neutrophils in healthy controls. There was a negative correlation between absolute neutrophil counts and severe infections in HiDAC- and IDAC-treated patients with a later onset of infections in IDAC patients (median: IDAC, day 18; HiDAC, day 16). Together, functionally mature neutrophils are detectable at least until day 10 in patients treated with HiDAC or IDAC, and may explain the relatively low hematologic toxicity of these consolidation protocols. IDAC is a superior protocol in this regard and may therefore be most suitable for elderly patients and those at high risk for severe infections.
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http://dx.doi.org/10.4049/jimmunol.176.3.1759DOI Listing
February 2006

Detection of molecular targets on the surface of CD34+/CD38-- stem cells in various myeloid malignancies.

Leuk Lymphoma 2006 Feb;47(2):207-22

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.

Recent data suggest that myeloid neoplasms are organized hierarchically in terms of self-renewal and maturation of early progenitor cells, similar to normal myelopoiesis. In acute myeloid leukemia (AML), the NOD/SCID mouse-repopulating leukemic stem cells usually co-express CD123 with CD34, but lack CD38. So far, however, little is known about expression of other markers and targets on these progenitors. In the present study, expression of target antigens on CD34+/CD38- cells was analysed by multi-color flow cytometry in patients with AML (n = 18), myelodysplastic syndromes (MDS, n = 6), chronic myeloid leukemia (CML, n = 8) and systemic mastocytosis (SM, n = 9). The IL-3Ralpha chain (CD123) was found to be expressed on CD34+/CD38- cells in a majority of the patients in all disease categories. Independent of the type of disease, the vast majority of these stem cells co-expressed aminopeptidase-N (CD13) and CD44 in all patients. By contrast, the CD34+/CD38- progenitor cells expressed variable amounts of the target receptor CD33, c-kit (CD117) and AC133 (CD133). In conclusion, neoplastic stem cells in various myeloid neoplasms appear to express a similar phenotype including target antigens such as CD13, CD33 and CD44. Since many of these targets are not expressed on all stem cells in all patients, the elimination of the entire clone may require combinations of targeted antibodies or use of additional drugs.
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http://dx.doi.org/10.1080/10428190500272507DOI Listing
February 2006

Myelomastocytic leukemia: evidence for the origin of mast cells from the leukemic clone and eradication by allogeneic stem cell transplantation.

Clin Cancer Res 2005 Oct;11(19 Pt 1):6787-92

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.

Purpose: Myelomastocytic leukemia is a term used for patients with advanced myeloid neoplasms, in whom elevated numbers of immature atypical mast cells are found, but criteria for a primary mast cell disease are not met. The origin of mast cells in these patients is presently unknown.

Patient And Methods: We have analyzed clonality of mast cells in an 18-year-old patient suffering from acute myeloid leukemia with a complex karyotype including a t(8;21) and mastocytic transformation with a huge increase in immature mast cells and elevated serum tryptase level, but no evidence for a primary mast cell disease/mastocytosis.

Results: As assessed by in situ fluorescence hybridization combined with tryptase staining, both the tryptase-negative blast cells and the tryptase-positive mast cells were found to contain the t(8;21)-specific AML1/ETO fusion gene. Myeloablative stem cell transplantation resulted in complete remission with consecutive disappearance of AML1/ETO transcripts, decrease of serum tryptase to normal range, and disappearance of neoplastic mast cells.

Conclusion: These data suggest that mast cells directly derive from the leukemic clone in patients with myelomastocytic leukemia.
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http://dx.doi.org/10.1158/1078-0432.CCR-05-1064DOI Listing
October 2005

Cell surface membrane antigen phenotype of human gastrointestinal mast cells.

Int Arch Allergy Immunol 2005 Oct 20;138(2):111-20. Epub 2005 Sep 20.

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.

Background: Mast cells (MC) are important effector cells of allergic and inflammatory reactions in diverse organs. These cells interact with a number of other immune cells and structural cells in the tissues as well as with proinflammatory mediators and cytokines. The various interactions are considered to be mediated through distinct cell surface membrane receptors on MC.

Methods: In the present study, we have established the cell surface membrane phenotype of human gastrointestinal MC (HGMC) using a panel of monoclonal antibodies and indirect immunofluorescence staining techniques.

Results: HGMC were found to react with antibodies against CD29, CD33, CD44, CD45, CD47, CD54, CD55, CD58, CD63, CD117, CD147, CD151, CD172a, and CD203c. By contrast, HGMC did not express detectable amounts of CD1, CD2, CD4, CD5, CD14, CD15, CD16, CD22, CD24, CD25, CD26, CD27, CD28, CD31, CD32, CD34, CD35, CD88, or CD116. The alpha-chain of the IL-3 receptor (CD123) was detectable neither in resting HGMC nor in HGMC exposed to stem cell factor and interleukin-4.

Conclusions: HGMC express a unique profile of surface antigens including the receptor for mast cell growth factor, adhesion-related molecules, and activation-linked membrane antigens.
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http://dx.doi.org/10.1159/000088432DOI Listing
October 2005

Expression of cell surface antigens on mast cells: mast cell phenotyping.

Methods Mol Biol 2006 ;315:77-90

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.

During the past few decades, a number of functionally important cell surface antigens have been detected on human mast cells (MCs). These antigens include the stem cell factor receptor (SCFR/CD117), the high-affinity immunoglobulin E receptor, adhesion molecules, and activation-linked membrane determinants. Several of these antigens (CD2, CD25, CD35, CD88, CD203c) appear to be upregulated on MCs in patients with systemic mastocytosis and therefore are used as diagnostic markers. Quantitative measurement of these markers on MCs is thus of diagnostic value and is usually performed by multicolor-based flow cytometry techniques utilizing a PE- or APC-labeled antibody against CD117 for MCs detection. This chapter gives an overview about the methods of staining of MC in various tissues with special reference to novel diagnostic markers applied in patients with suspected systemic mastocytosis.
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http://dx.doi.org/10.1385/1-59259-967-2:077DOI Listing
December 2005

CD 33 as a target of therapy in acute myeloid leukemia: current status and future perspectives.

Leuk Lymphoma 2005 Aug;46(8):1115-20

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.

CD 33 is a myeloid cell surface antigen that is expressed on blast cells in acute myeloid leukemia (AML) in a majority of all patients regardless of age or subtype of disease. The antigen is also expressed on leukemic stem cells in many cases, but is not expressed on normal hematopoietic stem cells. In an attempt to improve therapy in AML, a CD 33-targeted drug has been developed. The drug, gemtucumab ozogamicin (GO; Mylotarg), consists of a humanized CD 33 antibody (hP 67.6), a pH-dependent linker, and a highly potent chemotherapy agent, calicheamicin 1,2,-dimethyl hydrazine dichloride. Based on its clinical activity, GO has been approved for application in chemotherapy-refractory AML in various countries and is effective as a mono-substance as well as in combination with conventional chemotherapy. However, despite high efficacy and a certain specificity for leukemic (as opposed to normal) stem cells, the drug does not work in all patients, and can produce significant side-effects, including veno-occlusive disease (VOD), especially in patients who undergo stem cell transplantation. These side-effects have to be balanced against the benefit of GO therapy in patients with relapsed or refractory AML.
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http://dx.doi.org/10.1080/10428190500126075DOI Listing
August 2005

Identification of mTOR as a novel bifunctional target in chronic myeloid leukemia: dissection of growth-inhibitory and VEGF-suppressive effects of rapamycin in leukemic cells.

FASEB J 2005 Jun 22;19(8):960-2. Epub 2005 Mar 22.

Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.

The mammalian target of rapamycin (mTOR) has recently been described to be constitutively activated in Bcr-Abl-transformed cells and to mediate rapamycin-induced inhibition of growth in respective cell lines. We have recently shown that rapamycin down-regulates expression of vascular endothelial growth factor (VEGF), a mediator of leukemia-associated angiogenesis, in primary CML cells. In the present study, we analyzed growth-inhibitory in vitro and in vivo effects of rapamycin on primary CML cells and asked whether rapamycin-induced suppression of VEGF in leukemic cells is related to growth inhibition. Rapamycin dose dependently inhibited growth of primary CML cells obtained from patients with imatinib-responsive or imatinib-resistant disease as well as growth of Bcr-Abl-transformed imatinib-resistant cell lines. Moreover, we observed potent cytoreductive effects of rapamycin in a patient with imatinib-resistant Bcr-Abl+ leukemia. The growth-inhibitory effects of rapamycin on CML cells were found to be associated with G1 cell cycle arrest and with induction of apoptosis. In all cell types tested, rapamycin was found to down-regulate expression of VEGF. However, exogenously added VEGF did not counteract the rapamycin-induced decrease in proliferation. In conclusion, rapamycin inhibits growth of CML cells in vitro and in vivo and, in addition, down-regulates expression of VEGF. Both effects may contribute to the antileukemic activity of the drug in CML.
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http://dx.doi.org/10.1096/fj.04-1973fjeDOI Listing
June 2005

Evaluation of normal and neoplastic human mast cells for expression of CD172a (SIRPalpha), CD47, and SHP-1.

J Leukoc Biol 2005 Jun 22;77(6):984-92. Epub 2005 Mar 22.

Department of Internal Medicine, Division of Hematology & Hemostaseology, Medical University of Vienna, Austria.

Signal regulatory proteins (SIRPs) and tyrosine phosphatases have recently been implicated in the control of receptor tyrosine kinase (RTK)-dependent cell growth. In systemic mastocytosis (SM), neoplastic cells are driven by the RTK KIT, which is mutated at codon 816 in most patients. We examined expression of SIRPalpha, SIRPalpha ligand CD47, and Src homology 2 domain-containing protein tyrosine phosphatase-1 (SHP-1), a tyrosine phosphatase-type, negative regulator of KIT-dependent signaling, in normal human lung mast cells (HLMC) and neoplastic MC obtained from nine patients with SM. As assessed by multicolor flow cytometry, normal LMC expressed SIRPalpha, CD47, and SHP-1. In patients with SM, MC also reacted with antibodies against SIRPalpha and CD47. By contrast, the levels of SHP-1 were low or undetectable in MC in most cases. Corresponding data were obtained from mRNA analysis. In fact, whereas SIRPalpha mRNA and CD47 mRNA were detected in all samples, the levels of SHP-1 mRNA varied among donors. To demonstrate adhesive functions for SIRPalpha and CD47 on neoplastic MC, an adhesion assay was applied using the MC leukemia cell line HMC-1, which was found to bind to immobilized extracellular domains of SIRPalpha1 (SIRPalpha1ex) and CD47 (CD47ex), and binding of these cells to CD47ex was inhibited by the CD172 antibody SE5A5. In summary, our data show that MC express functional SIRPalpha and CD47 in SM, whereas expression of SHP-1 varies among donors and is low compared with LMC. It is hypothesized that CD172 and CD47 contribute to MC clustering and that the "lack" of SHP-1 in MC may facilitate KIT-dependent signaling in a subgroup of patients.
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http://dx.doi.org/10.1189/jlb.0604349DOI Listing
June 2005

Gain of structure and IgE epitopes by eukaryotic expression of the major Timothy grass pollen allergen, Phl p 1.

FEBS J 2005 Jan;272(1):217-27

Department of Pathophysiology, Center for Physiology and Pathophysiology, Medical University of Vienna, Austria.

Approximately 400 million allergic patients are sensitized against group 1 grass pollen allergens, a family of highly cross-reactive allergens present in all grass species. We report the eukaryotic expression of the group 1 allergen from Timothy grass, Phl p 1, in baculovirus-infected insect cells. Domain elucidation by limited proteolysis and mass spectrometry of the purified recombinant glycoprotein indicates that the C-terminal 40% of Phl p 1, a major IgE-reactive segment, represents a stable domain. This domain also exhibits a significant sequence identity of 43% with the family of immunoglobulin domain-like group 2/3 grass pollen allergens. Circular dichroism analysis demonstrates that insect cell-expressed rPhl p 1 is a folded species with significant secondary structure. This material is well behaved and is adequate for the growth of crystals that diffract to 2.9 A resolution. The importance of conformational epitopes for IgE recognition of Phl p 1 is demonstrated by the superior IgE recognition of insect-cell expressed Phl p 1 compared to Escherichia coli-expressed Phl p 1. Moreover, insect cell-expressed Phl p 1 induces potent histamine release and leads to strong up-regulation of CD203c in basophils from grass pollen allergic patients. Deglycosylated Phl p 1 frequently exhibits higher IgE binding capacity than the recombinant glycoprotein suggesting that rather the intact protein structure than carbohydrate moieties themselves are important for IgE recognition of Phl p 1. This study emphasizes the important contribution of conformational epitopes for the IgE recognition of respiratory allergens and provides a paradigmatic tool for the structural analysis of the IgE allergen interaction.
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http://dx.doi.org/10.1111/j.1432-1033.2004.04403.xDOI Listing
January 2005
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