Arnold Ganser

Publications of Arnold Ganser

• ID1 expression associates with other molecular markers and is not an independent prognostic factor in cytogenetically normal acute myeloid leukaemia.

  Authors: Frederik Damm, Katharina Wagner, Kerstin Görlich, Michael Morgan, Felicitas Thol, Haiyang Yun, Ruud Delwel, Peter J M Valk, Bob Löwenberg, Michael Heuser, Arnold Ganser, Jürgen Krauter

  British journal of haematology. 05/2012;

  In acute myeloid leukaemia with normal karyotype (CN-AML), gene mutations (e.g. NPM1, FLT3, CEBPA ) as well as deregulated gene expression affect outcome. High expression of ID1 was described as aIn acute myeloid leukaemia with normal karyotype (CN-AML), gene mutations (e.g. NPM1, FLT3, CEBPA ) as well as deregulated gene expression affect outcome. High expression of ID1 was described as a negative prognostic factor. We have shown that CEBPA regulates ID1 expression. Therefore, we analysed the prognostic impact of ID1 expression in 269 patients (aged 16-60 years) with CN-AML in the context of other molecular markers, particularly CEBPA mutations. ID1 (high) status was an independent negative prognostic factor for overall survival (OS) in multivariate analysis when analysed together with age, extramedullary disease, platelets, expression of BAALC and WT1, FLT3-internal tandem duplication, NPM1, WT1 single nucleotide polymorphism rs16754 and IDH1. ID1 expression was higher in CEBPA wildtype patients than in patients with monoallelic CEBPA mutations and these patients showed higher ID1 expression compared to patients with biallelic CEBPA mutations. Thus, when CEBPA mutations were considered, ID1 expression lost its prognostic impact. Likewise, the negative impact of ID1 (high) status on relapse-free survival (RFS) was lost when CEBPA mutations were included in the analysis. In CEBPA wildtype patients, ID1 expression had no impact on complete remission-rate, OS or RFS. In conclusion, CEBPA mutations seem to deregulate ID1 expression. Therefore, ID1 expression is not an independent prognostic factor in CN-AML.

• Immunosuppressive Therapy for Myelodysplastic Syndromes.

  Authors: Christiane Dobbelstein, Arnold Ganser

  Current pharmaceutical design. 05/2012;

  Myelodysplastic syndromes (MDS) comprise a heterogeneous group of diseases characterized by bone marrow failure, marrow dysplasia, and a tendency to evolve to acute leukemia. Pathophysiologically,Myelodysplastic syndromes (MDS) comprise a heterogeneous group of diseases characterized by bone marrow failure, marrow dysplasia, and a tendency to evolve to acute leukemia. Pathophysiologically, low risk MDS are separated from the high risk category by an increased rate of apoptosis of the bone marrow cells which causes the morphological paradoxon of a peripheral cytopenia and hypercellular bone marrow known as ineffective hematopoesis. Laboratory findings and clinical evidence suggest that some patients with myelodysplastic syndrome have immunologically mediated disease. MDS shares some of the features of acquired aplastic anemia and up to 30% of patients with MDS respond to immunosuppressive treatment. In the last decades, significant advances have been made in the diagnostic and prognostic classifications of myelodysplastic syndromes. While allogeneic transplantation still offers the only available option with a probability of cure in a minority of patients, the mainstay of therapy in low-risk patients remains supportive care, stimulation of ineffective hematopoiesis with growth factors, and immunomodulatory therapy. However, the correct selection of patients for the respective therapeutic intervention continues to be an enormous challenge as this will decide about the probability of therapeutic efficacy. This is important not only because of the high costs involved but also because of the possible side effects that can be difficult to manage. Here we review the pathophysiologic basis for the use of immunosuppressive agents in MDS and summarize the trials leading to the establishment of these therapy strategies in a subgroup of low-risk MDS patients.

• Prognostic significance of combined MN1, ERG, BAALC, and EVI1 (MEBE) expression in patients with myelodysplastic syndromes.

  Authors: Felicitas Thol, Haiyang Yun, Ann-Kathrin Sonntag, Frederik Damm, Eva M Weissinger, Jürgen Krauter, Katharina Wagner, Michael Morgan, Martin Wichmann, Gudrun Göhring, Gesine Bug, Oliver Ottmann, Wolf-Karsten Hofmann, Axel Schambach, Brigitte Schlegelberger, Torsten Haferlach, David Bowen, Ken Mills, Arnold Ganser, Michael Heuser

  Annals of hematology. 04/2012;

  Overexpression of MN1, ERG, BAALC, and EVI1 (MEBE) genes in cytogenetically normal acute myeloid leukemia (AML) patients is associated with poor prognosis, but their prognostic effect in patientsOverexpression of MN1, ERG, BAALC, and EVI1 (MEBE) genes in cytogenetically normal acute myeloid leukemia (AML) patients is associated with poor prognosis, but their prognostic effect in patients with myelodysplastic syndromes (MDS) has not been studied systematically. Expression data of the four genes from 140 MDS patients were combined in an additive score, which was validated in an independent patient cohort of 110 MDS patients. A high MEBE score, defined as high expression of at least two of the four genes, predicted a significantly shorter overall survival (OS) (HR 2.29, 95 % CI 1.3-4.09, P = .005) and time to AML progression (HR 4.83, 95 % CI 2.01-11.57, P < .001) compared to a low MEBE score in multivariate analysis independent of karyotype, percentage of bone marrow blasts, transfusion dependence, ASXL1, and IDH1 mutation status. In a validation cohort of 110 MDS patients, a high MEBE score predicted shorter OS (HR 1.77; 95 % CI 1.04-3.0, P = .034) and time to AML progression (HR 3.0, 95 % CI 1.17-7.65, P = .022). A high MEBE expression score is an unfavorable prognostic marker in MDS and is associated with an increased risk for progression to AML. Expression of the MEBE genes is regulated by FLI1 and c-MYC, which are potential upstream targets of the MEBE signature.

• Next-generation sequencing for minimal residual disease monitoring in acute myeloid leukemia patients with FLT3-ITD or NPM1 mutations.

  Authors: Felicitas Thol, Britta Kölking, Frederik Damm, Katarina Reinhardt, Jan-Henning Klusmann, Dirk Reinhardt, Nils von Neuhoff, Martijn H Brugman, Brigitte Schlegelberger, Sebastian Suerbaum, Jürgen Krauter, Arnold Ganser, Michael Heuser

  Genes, chromosomes & cancer. 03/2012;

  Systematic assessment of minimal residual disease (MRD) in acute myeloid leukemia (AML) patients has been hampered by lack of a reliable, uniform MRD marker applicable to all patients. We evaluatedSystematic assessment of minimal residual disease (MRD) in acute myeloid leukemia (AML) patients has been hampered by lack of a reliable, uniform MRD marker applicable to all patients. We evaluated next-generation sequencing (NGS) for MRD assessment in AML patients (n = 80 samples). The ability of NGS technologies to generate thousands of clonal sequences makes it possible to determine the allelic ratio of sequence variants. Using NGS, we were able to determine the allelic ratio of different FLT3-internal tandem duplication (ITD) clones within one patient sample, in addition to resolution of FLT3-ITD insertion site, length, and sequence in a single analysis. Furthermore, NGS allowed us to study emergence of clonal dominance. Parallel assessment of MRD by NGS and quantitative real-time polymerase chain reaction in NPM1 mutated patients was concordant in 95% of analyzed samples (n = 38). The frequency of mutated alleles was linearly quantified by NGS. As NGS sensitivity is scalable depending on sequence coverage, it reflects a highly flexible and reliable tool to assess MRD in leukemia patients. © 2012 Wiley Periodicals, Inc.

• Adults with acute lymphoblastic leukemia and molecular failure display a poor prognosis and are candidates for stem cell transplantation and targeted therapies.

  Authors: Nicola Gökbuget, Michael Kneba, Thorsten Raff, Heiko Trautmann, Claus-Rainer Bartram, Renate Arnold, Rainer Fietkau, Mathias Freund, Arnold Ganser, Wolf-Dieter Ludwig, Georg Maschmeyer, Harald Rieder, Stefan Schwartz, Hubert Serve, Eckhard Thiel, Monika Brüggemann, Dieter Hoelzer

  Blood. 03/2012;

  Quantification of minimal residual disease (MRD) by real-time polymerase chain reaction directed to T-cell-receptor and immunoglobulin gene rearrangements allows a refined evaluation of response inQuantification of minimal residual disease (MRD) by real-time polymerase chain reaction directed to T-cell-receptor and immunoglobulin gene rearrangements allows a refined evaluation of response in acute lymphoblastic leukemia (ALL). The German Multicenter Study Group for Adult ALL prospectively evaluated molecular response after induction/consolidation chemotherapy according to standardized methods and terminology in patients with Philadelphia chromosome-negative ALL. The cytological complete response (CR) rate was 89% after induction phase I and II. At this time-point the molecular CR rate was 70% in 580 patients with cytological CR and evaluable MRD. Patients with molecular CR after consolidation had a significantly higher probability of continuous complete remission (CCR) (74% vs. 35%; p<0.0001) and of overall survival (80% vs. 42%; p=0.0001) compared to patients with molecular failure. Patients with molecular failure without stem cell transplantation (SCT) in first CR relapsed after a median time of 7.6 months; CCR and survival at 5 years only reached 12% and 33%, respectively. Quantitative MRD assessment identified patients with molecular failure as a new high-risk group. These patients display resistance to conventional drugs and are candidates for treatment with targeted, experimental drugs and allogeneic SCT. Molecular response was shown to be highly predictive for outcome and therefore constitutes a relevant study endpoint. The studies are registered at www.clinicaltrials.gov as NCT00199056 and NCT00198991.

• Progression free survival of first line vascular endothelial growth factor-targeted therapy is an important prognostic parameter in patients with metastatic renal cell carcinoma.

  Authors: Christoph Seidel, Jonas Busch, Steffen Weikert, Sandra Steffens, Martin Fenner, Arnold Ganser, Viktor Grünwald

  European journal of cancer (Oxford, England : 1990). 03/2012;

  PURPOSE: Intrinsic resistance in metastatic renal cell carcinoma (mRCC) was recently associated with poor overall survival (OS), suggesting that VEGF inhibitor sensitivity may represent a valuablePURPOSE: Intrinsic resistance in metastatic renal cell carcinoma (mRCC) was recently associated with poor overall survival (OS), suggesting that VEGF inhibitor sensitivity may represent a valuable prognostic marker. We explored the duration of progression free survival (PFS) in first-line treatment and other variables as prognostic markers in mRCC. METHODS: Medical records from 119 mRCC patients receiving first line treatment with tyrosine kinase inhibitors (TKI) were retrieved retrospectively. Kaplan-Meier and log-rank analyses were employed on PFS and OS and multivariate Cox proportional hazard model analysed clinical parameters for their prognostic relevance. RESULTS: The median PFS of first line treatment was 8.4months (95% confidence interval 5.8-11) associated with a median OS of 28.2months (95% CI 20.9-35.4). Second line therapy with another TKI or mTOR-inhibitor was applied to 81 patients (68%). PFS of any second line therapy was 5.1 and 3.7months in first line treatment responders and non-responders (p=0.3), respectively. Univariate analyses revealed bone metastases, prior cytokine treatment, Memorial Sloan Kettering cancer centre (MSKCC) score, objective response rate, Eastern Cooperative Oncology Group (ECOG) performance status, first line PFS with 6months taken as cut-off parameter and second line treatment as prognostic variables. Multivariate analyses proved first line PFS above 6months (95% CI 0.154-0.641; HR 0.314), second line treatment (95% CI 0.162-0.657; HR 0.326), MSKCC score (95% CI 1.07-3.392; HR 1.905) and objective response rate (95% CI 0.358-0.989; HR 0.595) to be independent prognostic markers. CONCLUSIONS: The duration of first line PFS is an independent prognostic variable but not predictive for subsequent therapy.

• High-resolution genomic profiling of adult and pediatric core-binding factor acute myeloid leukemia reveals new recurrent genomic alterations.

  Authors: Michael W M Kühn, Ina Radtke, Lars Bullinger, Salil Goorha, Jinjun Cheng, Jennifer Edelmann, Juliane Gohlke, Xiaoping Su, Peter Paschka, Stanley Pounds [......] Verena I Gaidzik, Sheila Shurtleff, Jan Krönke, Karlheinz Holzmann, Jing Ma, Richard F Schlenk, Jeffrey E Rubnitz, Konstanze Döhner, Hartmut Döhner, James R Downing

  Blood. 03/2012; 119(10):e67-75.

  To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemiaTo identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia.

• Frequency and prognostic impact of mutations in SRSF2, U2AF1, and ZRSR2 in patients with myelodysplastic syndromes.

  Authors: Felicitas Thol, Sofia Kade, Carola Schlarmann, Patrick Löffeld, Michael Morgan, Jürgen Krauter, Marcin W Wlodarski, Britta Kölking, Martin Wichmann, Kerstin Görlich, Gudrun Göhring, Gesine Bug, Oliver Ottmann, Charlotte M Niemeyer, Wolf-Karsten Hofmann, Brigitte Schlegelberger, Arnold Ganser, Michael Heuser

  Blood. 03/2012;

  Mutations in genes of the splicing machinery have recently been described in MDS. In this study, we examined a cohort of 193 MDS patients for mutations in SRSF2, U2AF1 (synonym U2AF35), ZRSR2, and,Mutations in genes of the splicing machinery have recently been described in MDS. In this study, we examined a cohort of 193 MDS patients for mutations in SRSF2, U2AF1 (synonym U2AF35), ZRSR2, and, as previously reported, SF3B1 in the context of other molecular markers including mutations in ASXL1, RUNX1, NRAS, TP53, IDH1, IDH2, NPM1 and DNMT3A. Mutations in SRSF2, U2AF1, ZRSR2, and SF3B1 were found in 24 (12.4%), 14 (7.3%), 6 (3.1%), and 28 (14.5%) patients, respectively, corresponding to a total of 67 of 193 MDS patients (34.7%). SRSF2 mutations were associated with RUNX1 (P<.001) and IDH1 mutations (P=.013), while U2AF1 mutations were associated with ASXL1 (P=.005) and DNMT3A (P=.004) mutations. In univariate analysis, mutated SRSF2 predicted shorter overall survival (OS) and more frequent AML progression compared to wildtype SRSF2, whereas mutated U2AF1, ZRSR2, and SF3B1 had no impact on patient outcome. In multivariate analysis, SRSF2 remained an independent poor risk marker for OS (HR 2.3; 95%CI 1.28-4.13; P=.017) and AML progression (HR 2.83; 95%CI 1.31-6.12; P=.008). These results show a negative prognostic impact of SRSF2 mutations in MDS. SRSF2 mutations may become useful for clinical risk stratification and treatment decisions in the future.

• Cutaneous side effects of new antitumor drugs: clinical features and management.

  Authors: Ralf Gutzmer, Andreas Wollenberg, Selma Ugurel, Bernhard Homey, Arnold Ganser, Alexander Kapp

  Deutsches Ärzteblatt international. 02/2012; 109(8):133-40.

  Many new antitumor drugs have been approved in recent years. Their side-effect profiles are distinct from those of older drugs, and their adverse effects are sometimes highly specific, particularlyMany new antitumor drugs have been approved in recent years. Their side-effect profiles are distinct from those of older drugs, and their adverse effects are sometimes highly specific, particularly with respect to the skin. This article is based on articles retrieved by a selective search in Medline and the database of the American Society of Clinical Oncology (ASCO), as well as on the authors' personal experience. Cutaneous adverse effects are among the more common adverse effects of new antitumor drugs: they occur in up to 34% of patients receiving multikinase inhibitors, up to 90% of those receiving selective tyrosine kinase inhibitors (such as EGFR or mutant BRAF inhibitors), and up to 68% of those receiving immunotherapeutic agents (such as CTLA4 inhibitors). These adverse effects can be correlated with therapeutic benefit, but they can also be treatment-limiting because of their severity or visibility. The recognition and proper management of cutaneous adverse effects is an important part of treatment with new antitumor drugs.

• Identity, potency, in vivo viability, and scaling up production of lentiviral vector-induced dendritic cells for melanoma immunotherapy.

  Authors: Mudita Pincha, Bala Sai Sundarasetty, Gustavo Salguero, Ralf Gutzmer, Henk Garritsen, Laura Macke, Andreas Schneider, Daniela Lenz, Constanca Figueiredo, Rainer Blasczyk, Eliana Ruggiero, Manfred Schmidt, Christof von Kalle, Christina Puff, Ute Modlich, Heiko von der Leyen, Daniel C Wicke, Arnold Ganser, Renata Stripecke

  Human gene therapy. Part B. Methods. 02/2012; 23(1):38-55.

  Abstract SmartDCs (Self-differentiated Myeloid-derived Antigen-presenting-cells Reactive against Tumors) consist of highly viable dendritic cells (DCs) induced to differentiate with lentiviralAbstract SmartDCs (Self-differentiated Myeloid-derived Antigen-presenting-cells Reactive against Tumors) consist of highly viable dendritic cells (DCs) induced to differentiate with lentiviral vectors (LVs) after an overnight ex vivo transduction. Tricistronic vectors co-expressing cytokines (granulocyte-macrophage-colony stimulating factor [GM-CSF], interleukin [IL]-4) and a melanoma antigen (tyrosine related protein 2 [TRP2]) were used to transduce mouse bone marrow cells or human monocytes. Sixteen hours after transduction, the cells were dispensed in aliquots and cryopreserved for identity, potency, and safety analyses. Thawed SmartDCs readily differentiated into highly viable cells with a DC immunophenotype. Prime/boost subcutaneous administration of 1×10(6) thawed murine SmartDCs into C57BL/6 mice resulted into TRP2-specific CD8(+) T-cell responses and protection against lethal melanoma challenge. Human SmartDC-TRP2 generated with monocytes obtained from melanoma patients secreted endogenous cytokines associated with DC activation and stimulated TRP2-specific autologous T-cell expansion in vitro. Thawed human SmartDCs injected subcutaneously in NOD.Rag1(-/-).IL2rγ(-/-) mice maintained DC characteristics and viability for 1 month in vivo and did not cause any signs of pathology. For development of good manufacturing practices, CD14(+) monocytes selected by magnetic-activated cell separation were transduced in a closed bag system (multiplicity of infection of 5), washed, and cryopreserved. Fifty percent of the monocytes used for transduction were recovered for cryopreservation. Thawed SmartDCs produced in two independent runs expressed the endogenous cytokines GM-CSF and IL-4, and the resulting homogeneous SmartDCs that self-differentiated in vitro contained approximately 1.5-3.0 copies of integrated LVs per cell. Thus, this method facilitates logistics, standardization, and high recovery for the generation of viable genetically reprogrammed DCs for clinical applications.

• TP53 alterations in acute myeloid leukemia with complex karyotype correlate with specific copy number alterations, monosomal karyotype, and dismal outcome.

  Authors: Frank G Rücker, Richard F Schlenk, Lars Bullinger, Sabine Kayser, Veronica Teleanu, Helena Kett, Marianne Habdank, Carla-Maria Kugler, Karlheinz Holzmann, Verena I Gaidzik [......] Marie von Lilienfeld-Toal, Michael Lübbert, Stefan Fröhling, Thorsten Zenz, Jürgen Krauter, Brigitte Schlegelberger, Arnold Ganser, Peter Lichter, Konstanze Döhner, Hartmut Döhner

  Blood. 12/2011; 119(9):2114-21.

  To assess the frequency of TP53 alterations and their correlation with other genetic changes and outcome in acute myeloid leukemia with complex karyotype (CK-AML), we performed integrative analysisTo assess the frequency of TP53 alterations and their correlation with other genetic changes and outcome in acute myeloid leukemia with complex karyotype (CK-AML), we performed integrative analysis using TP53 mutational screening and array-based genomic profiling in 234 CK-AMLs. TP53 mutations were found in 141 of 234 (60%) and TP53 losses were identified in 94 of 234 (40%) CK-AMLs; in total, 164 of 234 (70%) cases had TP53 alterations. TP53-altered CK-AML were characterized by a higher degree of genomic complexity (aberrations per case, 14.30 vs 6.16; P < .0001) and by a higher frequency of specific copy number alterations, such as -5/5q-, -7/7q-, -16/16q-, -18/18q-, +1/+1p, and +11/+11q/amp11q13∼25; among CK-AMLs, TP53-altered more frequently exhibited a monosomal karyotype (MK). Patients with TP53 alterations were older and had significantly lower complete remission rates, inferior event-free, relapse-free, and overall survival. In multivariable analysis for overall survival, TP53 alterations, white blood cell counts, and age were the only significant factors. In conclusion, TP53 is the most frequently known altered gene in CK-AML. TP53 alterations are associated with older age, genomic complexity, specific DNA copy number alterations, MK, and dismal outcome. In multivariable analysis, TP53 alteration is the most important prognostic factor in CK-AML, outweighing all other variables, including the MK category.

• Monosomal karyotype in adult acute myeloid leukemia: prognostic impact and outcome after different treatment strategies.

  Authors: Sabine Kayser, Manuela Zucknick, Konstanze Döhner, Jürgen Krauter, Claus-Henning Köhne, Heinz A Horst, Gerhard Held, Marie von Lilienfeld-Toal, Sibylla Wilhelm, Mathias Rummel [......] Katharina Götze, David Nachbaur, Brigitte Schlegelberger, Gudrun Göhring, Daniela Späth, Carina Morlok, Veronica Teleanu, Arnold Ganser, Hartmut Döhner, Richard F Schlenk

  Blood. 11/2011; 119(2):551-8.

  We aimed to determine the prognostic impact of monosomal karyotype (MK) in acute myeloid leukemia (AML) in the context of the current World Health Organization (WHO) classification and to evaluateWe aimed to determine the prognostic impact of monosomal karyotype (MK) in acute myeloid leukemia (AML) in the context of the current World Health Organization (WHO) classification and to evaluate the outcome of MK(+) patients after allogeneic HSCT. Of 1058 patients with abnormal cytogenetics, 319 (30%) were MK MK(+). MK(+) patients were significantly older (P = .0001), had lower white blood counts (P = .0006), and lower percentages of BM blasts (P = .0004); MK was associated with the presence of -5/5q-, -7, 7q-, abnl(12p), abnl(17p), -18/18q-, -20/20q-, inv(3)/t(3;3), complex karyotype (CK), and myelodysplasia (MDS)-related cytogenetic abnormalities (P < .0001, each); and NPM1 mutations (P < .0001), FLT3 internal tandem duplications (P < .0001), and tyrosine kinase domain mutations (P = .02) were less frequent in MK(+). Response to induction therapy and overall survival in MK(+) patients were dismal with a complete remission rate of 32.5% and a 4-year survival of 9%. MK retained its prognostic impact in AML with CK, AML with MDS-related cytogenetic abnormalities, and in a revised definition (MK-R) excluding cases with recurrent genetic abnormalities according to WHO classification and those with derivative chromosomes not leading to true monosomies. In younger patients, allogeneic HSCT from matched related and unrelated donors resulted in a limited improvement of overall survival.

• A multicenter phase II trial of decitabine as first-line treatment for older patients with acute myeloid leukemia judged unfit for induction chemotherapy.

  Authors: Michael Lübbert, Björn H Rüter, Rainer Claus, Claudia Schmoor, Mathias Schmid, Ulrich Germing, Andrea Kuendgen, Volker Rethwisch, Arnold Ganser, Uwe Platzbecker, Oliver Galm, Wolfram Brugger, Gerhard Heil, Björn Hackanson, Barbara Deschler, Konstanze Döhner, Anne Hagemeijer, Pierre W Wijermans, Hartmut Döhner

  Haematologica. 11/2011; 97(3):393-401.

  Background The treatment of acute myeloid leukemia of older, medically non-fit patients still poses a highly unmet clinical need, and only few large, prospective studies have been performed in thisBackground The treatment of acute myeloid leukemia of older, medically non-fit patients still poses a highly unmet clinical need, and only few large, prospective studies have been performed in this setting. Given the established activity of hypomethylating agents such as 5-aza-2'-deoxycytidine (decitabine) in myelodysplastic syndromes and acute myeloid leukemia with 20-30% bone marrow blasts, we investigated whether this drug is also active in patients with more than 30% blasts. DESIGN AND METHODS: To evaluate the efficacy and toxicity of decitabine in patients over 60 years old with untreated acute myeloid leukemia ineligible for induction chemotherapy, 227 patients (median age, 72 years), many with comorbidities, adverse cytogenetics and/or preceding myelodysplastic syndrome were treated with this hypomethylating agent. During the initial decitabine treatment (135 mg/m(2) total dose infused intravenously over 72 hours every 6 weeks), a median of two cycles was administered (range, 1-4). All-trans retinoic acid was administered to 100 patients during course 2. Fifty-two patients who completed four cycles of treatment subsequently received a median of five maintenance courses (range, 1-19) with a lower dose of decitabine (20 mg/m(2)) infused over 1 hour on 3 consecutive days every 4-6 weeks. RESULTS: The complete and partial remission rate was 26%, 95% CI (20%, 32%), and an antileukemic effect was noted in 26% of patients. Response rates did not differ between patients with or without adverse cytogenetics; patients with monosomal karyotypes also responded. The median overall survival from the start of decitabine treatment was 5.5 months (range, 0-57.5+) and the 1-year survival rate was 28%, 95%CI (22%,34%). Toxicities were predominantly hematologic. Conclusions Decitabine is well tolerated by older, medically non-fit patients with acute myeloid leukemia; myelosuppression is the major toxicity. The response rate and overall survival were not adversely influenced by poor-risk cytogenetics or myelodysplastic syndrome. Because of these encouraging results, randomized studies evaluating single-agent decitabine versus conventional treatment are warranted. The study is registered with the German Clinical Trials Registry, number DRKS00000069.

• Modulation of anthracycline-induced cytotoxicity by targeting the prenylated proteome in myeloid leukemia cells.

  Authors: Michael A Morgan, Fredrick O Onono, H Peter Spielmann, Thangaiah Subramanian, Michaela Scherr, Letizia Venturini, Iris Dallmann, Arnold Ganser, Christoph W M Reuter

  Journal of molecular medicine (Berlin, Germany). 09/2011; 90(2):149-61.

  Deregulation of Ras/ERK signaling in myeloid leukemias makes this pathway an interesting target for drug development. Myeloid leukemia cell lines were screened for idarubicin-induced apoptosis,Deregulation of Ras/ERK signaling in myeloid leukemias makes this pathway an interesting target for drug development. Myeloid leukemia cell lines were screened for idarubicin-induced apoptosis, cell-cycle progression, cell-cycle-dependent MAP kinase kinase (MEK-1/2) activation, and Top2 expression. Cell-cycle-dependent activation of MEK/ERK signaling was blocked using farnesyltransferase inhibitor (FTI) BMS-214,662 and dual prenyltransferase inhibitor (DPI) L-778,123 to disrupt Ras signaling. Idarubicin caused a G2/M cell-cycle arrest characterized by elevated diphosphorylated MEK-1/2 and Top2α expression levels. The FTI/DPIs elicited distinct effects on Ras signaling, protein prenylation, cell cycling and apoptosis. Combining these FTI/DPIs with idarubicin synergistically inhibited proliferation of leukemia cell lines, but the L-778,123+idarubicin combination exhibited synergistic growth inhibition over a greater range of drug concentrations. Interestingly, combined FTI/DPI treatment synergistically inhibited cell proliferation, induced apoptosis and nearly completely blocked protein prenylation. Inhibition of K-Ras expression by RNA interference or blockade of its post-translational prenylation led to increased BMS-214,662-induced apoptosis. Our results suggest that nearly complete inhibition of protein prenylation using an FTI + DPI combination is the most effective method to induce apoptosis and to block anthracycline-induced activation of ERK signaling.

• Rare occurrence of DNMT3A mutations in myelodysplastic syndromes.

  Authors: Felicitas Thol, Claudia Winschel, Andrea Lüdeking, Haiyang Yun, Inna Friesen, Frederik Damm, Katharina Wagner, Jürgen Krauter, Michael Heuser, Arnold Ganser

  Haematologica. 08/2011; 96(12):1870-3.

  Gene mutations and epigenetic changes have been shown to play significant roles in the pathogenesis of myelodysplastic syndromes. Recently, mutations in DNMT3A were identified in 22.1% of patientsGene mutations and epigenetic changes have been shown to play significant roles in the pathogenesis of myelodysplastic syndromes. Recently, mutations in DNMT3A were identified in 22.1% of patients with acute myeloid leukemia. In this study, we analyzed the frequency and clinical impact of DNMT3A mutations in a cohort of 193 patients with myelodysplastic syndromes. Mutations in DNMT3A were found in 2.6% of patients. The majority of mutations were heterozygous missense mutations affecting codon R882. Patients with DNMT3A mutations were found to have a higher rate of transformation to acute myeloid leukemia. When assessing the global methylation levels in patients with mutated versus unmutated DNMT3A and healthy controls no difference in global DNA methylation levels between the two groups was seen. Our data show that in patients with myelodysplastic syndromes, DNMT3A mutations occur at a low frequency and may be a risk factor for leukemia progression.

• Isolation strategies of regulatory T cells for clinical trials: phenotype, function, stability, and expansion capacity.

  Authors: Sya N Ukena, Matthias Höpting, Sarvari Velaga, Philipp Ivanyi, Jens Grosse, Udo Baron, Arnold Ganser, Anke Franzke

  Experimental hematology. 08/2011; 39(12):1152-60.

  Recent clinical results demonstrate the highly effective potency of regulatory T cells (Tregs) to control graft-versus-host disease (GvHD). In this presented study, we directly compared differentRecent clinical results demonstrate the highly effective potency of regulatory T cells (Tregs) to control graft-versus-host disease (GvHD). In this presented study, we directly compared different Treg subpopulations in order to define the most promising Treg target cell population for cellular intervention studies with respect to their phenotype, functional properties, stability, and expansion capacity. Different Treg cell populations have been isolated from healthy donors and characterized by fluorescence activated cell sorting (FACS) analysis for their phenotypic marker and purity, functional properties by suppression assay, stability by Treg-specific demethylated region (TSDR) of the Foxp3 promoter and their in vitro expansion capacity. The direct comparison of the respective Treg target cell populations identified CD4(+)CD25(hi)CD127(-) and CD4(+)CD25(hi)ICOS(+) Tregs as the most promising Treg population for fresh cell infusions in clinical trials with respect to cell yield, phenotype, function, and stability. The CD4(+)CD25(hi) Tregs qualified as the best candidate for in vitro expansion combining a highly stable phenotype with strong suppressive potential and attractive cell yield after repetitive stimulation. The suppressive capacity of freshly isolated CD4(+)CD25(hi)CD45RA(+) and CD49d(-)CD127(-) Tregs is comparable to freshly isolated CD4(+)CD25(hi), but inferior to CD4(+)CD25(hi)CD127(-) and CD4(+)CD25(hi)ICOS(+) Tregs. In vitro expansion of CD4(+)CD25(hi)CD45RA(+) and CD49d(-)CD127(-) Tregs resulted in cell populations with less suppressive potency compared with CD4(+)CD25(hi) expanded Tregs correlating well with a higher TSDR demethylation level. In conclusion, future clinical trials should favor CD4(+)CD25(hi)CD127(-) and CD4(+)CD25(hi)ICOS(+) Tregs for direct Treg cell transfer, whereas CD4(+)CD25(hi) Tregs qualify as best candidate for in vitro expansion.

• P-selectin glycoprotein ligand-1 positive microparticles in allogeneic stem cell transplantation of hematologic malignancies.

  Authors: Arne Trummer, Christiane De Rop, Michael Stadler, Arnold Ganser, Stefanie Buchholz

  Experimental hematology. 08/2011; 39(11):1047-55.

  P-selectin and its receptor P-selectin glycoprotein ligand-1 (PSGL-1) mediate adhesion between leukocytes, tumor cells (including leukemias and lymphomas), and platelets, and play an important roleP-selectin and its receptor P-selectin glycoprotein ligand-1 (PSGL-1) mediate adhesion between leukocytes, tumor cells (including leukemias and lymphomas), and platelets, and play an important role in hematopoiesis, T cell activation, and cancer growth and metastasis. As microparticles (MPs) are released from activated or apoptotic cells, there should be significant numbers of circulating PSGL-1-bearing MPs in the blood of patients undergoing allogeneic stem cell transplantation (alloSCT). We enumerated PSGL-1-expressing MPs in plasma samples from 30 consecutive patients with hematologic disorders at different time points during the course of alloSCT by flow cytometry and analyzed their relation to cell counts, patient characteristics, and clinical outcome. Median follow-up time of surviving patients was 1,772 days (range 1272-1981 days). Nineteen patients (63.3%) died, 10 due to progression of disease (33.3%). The PSGL-1 MPs significantly declined during conditioning therapy but increased again after transfusion of donor cells and even more at the time of engraftment. Numbers >250/μL after graft transfusion were associated with a shorter time to engraftment for patients receiving fresh peripheral stem cell grafts (median, 15 vs. 21 days; p = 0.049). Furthermore, low PSGL-1 MP values at those two time points were associated with a higher risk of progress/relapse in univariate analysis (p = 0.008-0.014; hazard ratio [HR] = 15.0-42.0) with cumulative incidences at 5 years of 81.8% versus 28.6% and 85.7% versus 20.0%, respectively. In conclusion, PSGL-1 microparticles show a characteristic course during alloSCT and their possible association with relapse/progress requires further evaluation of the PSGL-1/P-selectin interaction in leukemias and lymphomas.

• Human regulatory T cells in allogeneic stem cell transplantation.

  Authors: Sya N Ukena, Sarvari Velaga, Robert Geffers, Jens Grosse, Udo Baron, Stefanie Buchholz, Michael Stadler, Dunja Bruder, Arnold Ganser, Anke Franzke

  Blood. 07/2011; 118(13):e82-92.

  GVHD is still one of the major complications after allogeneic stem cell transplantation. Whereas murine data have clearly shown the beneficial effects of regulatory T cells (Tregs) on the preventionGVHD is still one of the major complications after allogeneic stem cell transplantation. Whereas murine data have clearly shown the beneficial effects of regulatory T cells (Tregs) on the prevention of GVHD, data from the human system are rare. Here, we present a comparative dynamic analysis of CD4(+)CD25(hi)CD127(lo/-) Tregs from patients with and without GVHD analyzing the whole genome profile over the first 6 months after stem cell transplantation, representing the most sensitive time window for tolerance induction. The Treg transcriptome showed a high stability. However, the comparison of Treg transcriptomes from patients with and without GVHD uncovered regulated gene transcripts highly relevant for Treg cell function. The confirmative protein analyses demonstrated a significantly higher expression of granzyme A, CXCR3, and CCR5 in Tregs of immune tolerant patients. These results point to a reduced suppressive function of Tregs from GVHD patients with diminished migration capacity to the target organs.

• A randomized phase 3 study of lenalidomide versus placebo in RBC transfusion-dependent patients with Low-/Intermediate-1-risk myelodysplastic syndromes with del5q.

  Authors: Pierre Fenaux, Aristoteles Giagounidis, Dominik Selleslag, Odile Beyne-Rauzy, Ghulam Mufti, Moshe Mittelman, Petra Muus, Peter Te Boekhorst, Guillermo Sanz, Consuelo Del Cañizo [......] Bruno Quesnel, Mario Cazzola, Arnold Ganser, David Bowen, Brigitte Schlegelberger, Carlo Aul, Robert Knight, John Francis, Tommy Fu, Eva Hellström-Lindberg

  Blood. 07/2011; 118(14):3765-76.

  This phase 3, randomized, double-blind study assessed the efficacy and safety of lenalidomide in 205 red blood cell (RBC) transfusion-dependent patients with International Prognostic Scoring SystemThis phase 3, randomized, double-blind study assessed the efficacy and safety of lenalidomide in 205 red blood cell (RBC) transfusion-dependent patients with International Prognostic Scoring System Low-/Intermediate-1-risk del5q31 myelodysplastic syndromes. Patients received lenalidomide 10 mg/day on days 1-21 (n = 69) or 5 mg/day on days 1-28 (n = 69) of 28-day cycles; or placebo (n = 67). Crossover to lenalidomide or higher dose was allowed after 16 weeks. More patients in the lenalidomide 10- and 5-mg groups achieved RBC-transfusion independence (TI) for ≥ 26 weeks (primary endpoint) versus placebo (56.1% and 42.6% vs 5.9%; both P < .001). Median duration of RBC-TI was not reached (median follow-up, 1.55 years), with 60% to 67% of responses ongoing in patients without progression to acute myeloid leukemia (AML). Cytogenetic response rates were 50.0% (10 mg) versus 25.0% (5 mg; P = .066). For the lenalidomide groups combined, 3-year overall survival and AML risk were 56.5% and 25.1%, respectively. RBC-TI for ≥ 8 weeks was associated with 47% and 42% reductions in the relative risks of death and AML progression or death, respectively (P = .021 and .048). The safety profile was consistent with previous reports. Lenalidomide is beneficial and has an acceptable safety profile in transfusion-dependent patients with Low-/Intermediate-1-risk del5q myelodysplastic syndrome. This trial was registered at www.clinicaltrials.gov as #NCT00179621.

• Cell of origin in AML: susceptibility to MN1-induced transformation is regulated by the MEIS1/AbdB-like HOX protein complex.

  Authors: Michael Heuser, Haiyang Yun, Tobias Berg, Eric Yung, Bob Argiropoulos, Florian Kuchenbauer, Gyeongsin Park, Iyas Hamwi, Lars Palmqvist, Courteney K Lai [......] Gordon Robertson, Martin Hirst, David Kent, Nicola K Wilson, Bertie Göttgens, Connie Eaves, Michael L Cleary, Marco Marra, Arnold Ganser, R Keith Humphries

  Cancer cell. 07/2011; 20(1):39-52.

  Pathways defining susceptibility of normal cells to oncogenic transformation may be valuable therapeutic targets. We characterized the cell of origin and its critical pathways in MN1-inducedPathways defining susceptibility of normal cells to oncogenic transformation may be valuable therapeutic targets. We characterized the cell of origin and its critical pathways in MN1-induced leukemias. Common myeloid (CMP) but not granulocyte-macrophage progenitors (GMP) could be transformed by MN1. Complementation studies of CMP-signature genes in GMPs demonstrated that MN1-leukemogenicity required the MEIS1/AbdB-like HOX-protein complex. ChIP-sequencing identified common target genes of MN1 and MEIS1 and demonstrated identical binding sites for a large proportion of their chromatin targets. Transcriptional repression of MEIS1 targets in established MN1 leukemias demonstrated antileukemic activity. As MN1 relies on but cannot activate expression of MEIS1/AbdB-like HOX proteins, transcriptional activity of these genes determines cellular susceptibility to MN1-induced transformation and may represent a promising therapeutic target.