Wolfgang E Berdel

Universitätsklinikum Münster, Muenster, North Rhine-Westphalia, Germany

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Publications (520)2842.42 Total impact

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    ABSTRACT: The DNA methyltransferase (DNMT) inhibitory drugs such as 5-azacytidine induce DNA hypomethylation by inhibiting DNA methyltransferases. While clinically effective, DNMT inhibitors are not curative. A combination with cytotoxic drugs might be beneficial, but this is largely unexplored. In the present study, we analyzed potential synergisms between cytotoxic drugs and 5-azacytidine in acute myeloid leukemia (AML) and non-small cell lung cancer (NSCLC) cells. Lung cancer and leukemia cell lines were exposed to low doses of 5-azacytidine with varying doses of cytarabine or etoposide for AML cells (U937 and HL60) as well as cisplatin or gemcitabine for NSCLC cells (A549 and HTB56) for 48 h. Drug interaction and potential synergism was analyzed according to the Chou-Talalay algorithm. Further analyses were based on soft agar colony formation assays, active caspase-3 staining and BrdU incorporation flow cytometry. To identify effects on DNA methylation patterns, we performed genome wide DNA methylation analysis using 450K bead arrays. Azacytidine at low doses was synergistic with cytotoxic drugs in NSCLC and in AML cell lines. Simultaneous exposure to 5-azacytidine with cytotoxic drugs showed strong synergistic activity. In colony formation assays these synergisms were repeatedly verified for 5-azacytidine (25 nM) with low doses of anticancer agents. 5-azacytidine neither affected the cell cycle nor increased apoptosis. 450K methylation bead arrays revealed 1,046 CpG sites in AML and 1,778 CpG sites in NSCLC cells with significant DNA hypomethylation (24-h exposure) to 5-azacytidine combined with the cytotoxic drugs. These CpG-sites were observed in the candidate tumor-suppressor genes MGMT and THRB. Additional incubation time after 24-h treatment led to a 4.1-fold increase of significant hypomethylated CpG-sites in NSCLC cells. These results suggest that the addition of DNA demethylating agents to cytotoxic anticancer drugs exhibits synergistic activity in AML and NSCLC. Dysregulation of an equilibrium of DNA methylation in cancer cells might increase the susceptibility for cytotoxic drugs.
    International journal of oncology. 12/2014;
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    ABSTRACT: The optimal timing of allogeneic hematopoietic transplantation (HCT) in AML is controversial. We report on 1179 patients with a median age of 48 years who were randomized upfront. In the control arm, sibling HCT was scheduled in the first complete remission for intermediate-risk or high-risk AML and matched unrelated HCT in complex karyotype AML. In the experimental arm, matched unrelated HCT in the first remission was offered also to patients with an FLT3-ITD allelic ratio >0.8, poor day +15 marrow blast clearance, and adverse karyotypes. Further, allogeneic HCT was recommended in high-risk AML to be performed in aplasia after induction chemotherapy.Leukemia accepted article preview online, 01 December 2014. doi:10.1038/leu.2014.335.
    Leukemia. 12/2014;
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    ABSTRACT: Recurrent respiratory papillomatosis (RRP) is a primary benign disease, which is characterized by papillomatous growth in the respiratory tract. Malignant transformation occurs in only 3-5% of cases, however, local growth of the benign papillomas is interpreted as clinically malignant in a markedly higher proportion of patients. Local surgical or endoscopic interventional debulking or excision is currently the commonly selected treatment method and antiviral therapy is a potential adjuvant approach. However, the long-term management of RRP patients, who commonly require multiple procedures over numerous years, is challenging and the overall therapeutic armamentarium remains unsatisfactory. The administration of systemic bevacizumab treatment in a series of five patients with long histories of RRP, who required repeated local interventions to control papilloma growth is evaluated. Treatment with the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab was administered at a dose of 5 mg/kg (n=1), 10 mg/kg (n=3) or 15 mg/kg (n=1) intravenously to the five RRP patients, who were clinically classified as exhibiting progressive disease. Endoscopic evaluations were performed prior to the first infusion of bevacizumab and intermittently at variable time points during the course of therapy. Histopathological analyses were performed using pre- and post-treatment papilloma biopsies, including immunohistochemical analyses of VEGF and phosphorylated VEGF receptor (VEGFR)-2 expression. The patients received between three and 16 courses of bevacizumab (median, six courses). The first course was initiated when progression following the previous intervention was observed. An immediate response to bevacizumab treatment was demonstrated in all five RRP patients. While the cumulative number of interventions in the five patients was 18 throughout the 12 months prior to the initiation of bevacizumab treatment, only one patient required interventional treatment due to a malignant transformation during the 12 months following treatment with bevacizumab (18 vs. 1 interventions, P=0.042). Histopathological analyses revealed regressive perivascular edema and normalization of the vascular structure, however, immunohistochemical analyses of the VEGF and phosphorylated VEGFR-2 expression did not demonstrate any changes following therapy. Due to the limited number of alternative treatments, VEGF-targeted therapies may represent a promising novel strategy in the treatment of RRP, which may have the potential to modify the current treatment standards, particularly in patients with poorly accessible papilloma lesions, however, this requires further investigation in clinical trials.
    Oncology letters 11/2014; 8(5):1912-1918. · 0.24 Impact Factor
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    ABSTRACT: Background The aim of this study was to analyze the long-term survival of AML patients with CEBPA mutations.Patients and methodsWe investigated 88 AML patients with a median age of 61 years and (1) cytogenetically normal AML (CN-AML), (2) monoallelic (moCEBPA) or biallelic (biCEBPA) CEBPA mutation, and (3) intensive induction treatment. 60/88 patients have been described previously with a shorter follow-up.ResultsMedian follow-up time was 9.8 years (95% CI: 9.4-10.1 years) compared to 3.2 and 5.2 years in our former analyses. Patients with biCEBPA survived significantly longer compared to those with moCEBPA (median overall survival (OS) 9.6 years vs. 1.7 years, p¿=¿0.008). Patients¿¿¿60 years and biCEBPA mutations showed a favorable prognosis with a 10-year OS rate of 81%.Both, bi- and moCEBPA-mutated groups had a low early death (d60) rate of 7% and 9%, respectively. Complete remission (CR) rates for biCEBPA- and moCEBPA-mutated patients were 82% vs. 70% (p¿=¿0.17). biCEBPA-mutated patients showed a longer relapse free survival (RFS) (median RFS 9.4 years vs. 1.5 years, p¿=¿0.021) and a lower cumulative incidence of relapse (CIR) compared to moCEBPA-mutated patients. These differences in OS and RFS were confirmed after adjustment for known clinical and molecular prognostic factors.Conclusions In this long-term observation we confirmed the favorable prognostic outcome of patients with biCEBPA mutations compared to moCEBPA-mutated CN-AML. The high probability of OS (81%) in younger patients is helpful to guide intensity of postremission therapy.
    Journal of Hematology & Oncology 09/2014; 7(1):55. · 4.46 Impact Factor
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    ABSTRACT: Apoptosis is a crucial pathway in tumor growth and metastatic development. Apoptotic proteins regulate the underlying molecular cascades and are thought to modulate the tumor response to chemotherapy and radiation. However, the prognostic value of the expression of apoptosis regulators in localized non-small-cell lung cancer (NSCLC) is still unclear.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 07/2014; · 4.55 Impact Factor
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    ABSTRACT: Isolated trisomy 13 (AML+13) is a rare chromosomal abnormality in acute myeloid leukemia (AML), and its prognostic relevance is poorly characterized. We analyzed the clinical course of 34 AML+13 patients enrolled in the German AMLCG-1999 and SAL trials and studied their biological characteristics by exome sequencing, targeted sequencing of candidate genes and gene expression profiling. Relapse-free (RFS) and overall survival (OS) of AML+13 patients were inferior compared to other ELN Intermediate-II patients (n=855) (median RFS, 7.8 vs 14.1 months, p=0.006; median OS 9.3 vs. 14.8 months, p=0.004). Besides the known high frequency of RUNX1 mutations (75%), we identified mutations in spliceosome components in 88%, including SRSF2 codon 95 mutations in 81%, of AML+13 patients. Moreover, recurring mutations were detected in ASXL1 (44%) and BCOR (25%). Two patients carried mutations in CEBPZ, suggesting that CEBPZ is a novel recurrently mutated gene in AML. Gene expression analysis revealed a homogenous expression profile including upregulation of FOXO1 and FLT3 and downregulation of SPRY2. This is the most comprehensive clinical and biological characterization of AML+13 to date, and reveals a striking clustering of lesions in a few genes, defining AML+13 as a genetically homogenous leukemia subgroup with alterations in a few critical cellular pathways. These studies were registered at clinicaltrials.gov, identifiers: AMLCG-1999: NCT00266136; AML96: NCT00180115; AML2003: NCT00180102; and AML60+: NCT00893373.
    Blood 06/2014; · 9.78 Impact Factor
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    ABSTRACT: In acute myeloid leukemia (AML), assessment of minimal residual disease (MRD) by flow cytometry (flow MRD) after induction and consolidation therapy has been shown to provide independent prognostic information. However, data on the value of earlier flow MRD assessment is lacking. Therefore, the value of flow MRD detection was determined during aplasia in 178 patients achieving complete remission after treatment according to AMLCG induction protocols. Flow MRD-positivity during aplasia predicted poor outcome (5-year relapse-free survival (RFS) 16% vs 43%, P<0.001) independently from age and cytogenetic risk group (hazard ratio for MRD-positivity 1.71; P=0.009). Importantly, the prognosis of patients without detectable MRD was not impacted by morphological blast count during aplasia nor by MRD status post-induction. Early flow MRD was also evaluated in the context of existing risk factors. Flow MRD was prognostic within the intermediate cytogenetic risk group (5-year RFS 15% vs. 37%, p=0.016) as well as for patients with normal karyotype and NPM1 mutations (5-year RFS 13% vs. 49%, P=0.02) or FLT3-ITD (3-year RFS rates 9% vs. 44%, P=0.016). Early flow MRD assessment can improve current risk stratification approaches by prediction of RFS in AML and might facilitate adaptation of post-remission therapy for patients at high risk of relapse.Leukemia accepted article preview online, 10 June 2014; doi:10.1038/leu.2014.186.
    Leukemia. 06/2014;
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    ABSTRACT: Monitoring of minimal residual disease represents an important diagnostic tool to identify patients with acute myeloid leukemia at high risk for relapse. In this study the prognostic potential of minimal residual disease monitoring by quantitative real-time PCR of NPM1 mutations of patients treated in the AMLCG trials 1999, 2004 and 2008 was investigated. Minimal residual disease monitoring was performed in 588 samples of 158 NPM1 mutation A, B and D positive patients at diagnosis, in aplasia, after induction therapy, after consolidation therapy, and during follow-up with a sensitivity of 10-6. 127 patients (80.4%) achieved complete remission after induction therapy and of these 56 patients (44.1%) relapsed. At each checkpoints, minimal residual disease cut-offs were calculated. After induction therapy a cut-off NPM1 mutation ratio of 0.01 revealed a high hazard ratio of 4.26 and the highest sensitivity of 76% for the prediction of relapse. This was reflected in a cumulative incidence of relapse after 2 years of 77.8% for cut-off positive patients versus 26.4% for cut-off negative patients, respectively. In the favorable subgroup according to European LeukemiaNet, the cut-off after induction therapy also separates the cohort into two prognostic groups with a cumulative incidence of relapse of 76% versus 6% after 2 years. Our data demonstrate that in addition to pre-therapeutic factors, the individual minimal residual disease course is an important prognostic factor and could be included into clinical trials for the guidance of postremission therapy. Trials were registered at www.clinicaltrials.gov (#NCT01382147, #NCT00266136) and at the European Leukemia Trial Registry (#LN_AMLINT2004_230).
    Haematologica 05/2014; · 5.94 Impact Factor
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    ABSTRACT: Cytogenetically normal (CN) acute myeloid leukemia (AML) is the largest and most heterogeneous cytogenetic AML subgroup. For the practicing clinician, it is difficult to summarize the prognostic information of the growing number of clinical and molecular markers. Our purpose was to develop a widely applicable prognostic model by combining well-established pretreatment patient and disease characteristics. Two prognostic indices for CN-AML (PINA), one regarding overall survival (OS; PINAOS) and the other regarding relapse-free survival (RFS; PINARFS), were derived from data of 572 patients with CN-AML treated within the AML Cooperative Group 99 study (www.aml-score.org. On the basis of age (median, 60 years; range, 17 to 85 years), performance status, WBC count, and mutation status of NPM1, CEBPA, and FLT3-internal tandem duplication, patients were classified into the following three risk groups according to PINAOS and PINARFS: 29% of all patients and 32% of 381 responding patients had low-risk disease (5-year OS, 74%; 5-year RFS, 55%); 56% of all patients and 39% of responding patients had intermediate-risk disease (5-year OS, 28%; 5-year RFS, 27%), and 15% of all patients and 29% of responding patients had high-risk disease (5-year OS, 3%; 5-year RFS, 5%), respectively. PINAOS and PINARFS stratified outcome within European LeukemiaNet genetic groups. Both indices were confirmed on independent data from Cancer and Leukemia Group B/Alliance trials. We have developed and validated, to our knowledge, the first prognostic indices specifically designed for adult patients of all ages with CN-AML that combine well-established molecular and clinical variables and that are easily applicable in routine clinical care. The integration of both clinical and molecular markers could provide a basis for individualized patient care through risk-adapted therapy of CN-AML.
    Journal of Clinical Oncology 04/2014; · 18.04 Impact Factor
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    ABSTRACT: ScopeIn previous studies, we could show that the B vitamin nicotinamide (NAM) enhanced antimicrobial activity of neutrophils. Here, we assessed the effects of NAM in two models of experimental colitis.Methods and ResultsColitis was induced in C57BL/6 mice either by oral infection with Citrobacter rodentium or by DSS (dextran sodium sulphate) administration, and animals were systemically treated with NAM. Ex vivo bacterial clearance was assessed in murine and human whole blood, as well as isolated human neutrophils. In C. rodentium-induced colitis, NAM treatment resulted in markedly decreased systemic bacterial invasion, histological damage and increased fecal clearance of C. rodentium by up to 600-fold. In contrast, NAM had no effect when administered to neutrophil-depleted mice. Ex vivo stimulation of isolated human neutrophils, as well as murine and human whole blood with NAM led to increased clearance of C. rodentium and enhanced expression of antimicrobial peptides in neutrophils. Moreover, NAM treatment significantly ameliorated the course of DSS colitis, as assessed by body weight, histological damage and myeloperoxidase activity.Conclusion Pharmacological application of NAM mediates beneficial effects in bacterial and chemically induced colitis. Future studies are needed to explore the clinical potential of NAM in the context of intestinal bacterial infections and human inflammatory bowel disease (IBD).
    Molecular Nutrition & Food Research 04/2014; · 4.31 Impact Factor
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    ABSTRACT: Acute myeloid leukaemia (AML) is a heterogenous disease. Prognosis of AML is influenced both by patient-specific as well as disease-specific factors. Age is the most prominent patient-specific risk factor, while chromosomal aberrations are the strongest disease-specific risk factors. For patients with cytogenetically normal AML, prognosis can be specified by mutational status of the genes NPM1, FLT3 and CEBPA. A growing number of recurrent mutations in additional genes have recently been identified, for which the prognostic effect yet has to be determined. Performance status, geriatric assessment, secondary leukaemia following myelodysplastic syndrome or cytotoxic treatment, common laboratory parameters, leukaemic stem cell frequency, bone marrow microenvironment, gene expression levels, epigenetic changes, micro-RNA's as well as kinetics and depth of response to treatment influence prognosis of AML patients. Despite the high number of established risk factors, only few predictive markers exist which can truly aid therapy decisions in patients with AML.
    British Journal of Haematology 02/2014; · 4.94 Impact Factor
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    ABSTRACT: External signals that are mediated by specific receptors determine stem cell fate. The thrombin receptor PAR1 plays an important role in haemostasis, thrombosis and vascular biology, but also in tumor biology and angiogenesis. Its expression and function in hematopoietic stem cells is largely unknown. Here, we analyzed expression and function of PAR1 in primary hematopoietic cells and their leukemic counterparts. AML patients' blast cells expressed much lower levels of PAR1 mRNA and protein than CD34+ progenitor cells. Constitutive Par1-deficiency in adult mice did not affect engraftment or stem cell potential of hematopoietic cells. To model an AML with Par1-deficiency, we retrovirally introduced the oncogene MLL-AF9 in wild type and Par1-/- hematopoietic progenitor cells. Par1-deficiency did not alter initial leukemia development. However, the loss of Par1 enhanced leukemic stem cell function in vitro and in vivo. Re-expression of PAR1 in Par1-/- leukemic stem cells delayed leukemogenesis in vivo. These data indicate that Par1 contributes to leukemic stem cell maintenance.
    PLoS ONE 01/2014; 9(4):e94993. · 3.53 Impact Factor
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    ABSTRACT: NPM1 mutations represent frequent genetic alterations in patients with acute myeloid leukemia (AML) associated with a favorable prognosis. Different types of NPM1 mutations have been described. The purpose of our study was to evaluate the relevance of different NPM1 mutation types with regard to clinical outcome. Our analyses were based on 349 NPM1-mutated AML patients treated in the AMLCG99 trial. Complete remission rates, overall survival and relapse-free survival were not significantly different between patients with NPM1 type A or rare type mutations. The NPM1 mutation type does not seem to play a role in risk stratification of cytogenetically normal AML.
    PLoS ONE 01/2014; 9(10):e109759. · 3.53 Impact Factor
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    ABSTRACT: Functional differences between healthy progenitor and cancer initiating cells may provide unique opportunities for targeted therapy approaches. Hematopoietic stem cells are tightly controlled by a network of CDK inhibitors that govern proliferation and prevent stem cell exhaustion. Loss of Inca1 led to an increased number of short-term hematopoietic stem cells in older mice, but Inca1 seems largely dispensable for normal hematopoiesis. On the other hand, Inca1-deficiency enhanced cell cycling upon cytotoxic stress and accelerated bone marrow exhaustion. Moreover, AML1-ETO9a-induced proliferation was not sustained in Inca1-deficient cells in vivo. As a consequence, leukemia induction and leukemia maintenance were severely impaired in Inca1-/- bone marrow cells. The re-initiation of leukemia was also significantly inhibited in absence of Inca1-/- in MLL-AF9- and c-myc/BCL2-positive leukemia mouse models. These findings indicate distinct functional properties of Inca1 in normal hematopoietic cells compared to leukemia initiating cells. Such functional differences might be used to design specific therapy approaches in leukemia.
    PLoS ONE 01/2014; 9(12):e115578. · 3.53 Impact Factor
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    ABSTRACT: About 30% of patients with acute myeloid leukemia (AML) harbour mutations of the receptor tyrosine kinase FLT3, mostly internal tandem duplications (ITD) and point mutations of the second tyrosine kinase domain (TKD). It was the aim of this study to comprehensively analyze clinical and functional properties of various FLT3 mutants. In 672 normal karyotype AML patients FLT3-ITD, but not FLT3-TKD mutations were associated with a worse relapse free and overall survival in multivariate analysis. In paired diagnosis-relapse samples FLT3-ITD showed higher stability (70%) compared to FLT3-TKD (30%). In vitro, FLT3-ITD induced a strong activating phenotype in Ba/F3 cells. In contrast, FLT3-TKD mutations and other point mutations - including two novel mutations - showed a weaker but clear gain-of-function phenotype with gradual increase in proliferation and protection from apoptosis. The pro-proliferative capacity of the investigated FLT3 mutants was associated with cell surface expression and tyrosine 591 phosphorylation of the FLT3 receptor. Western blot experiments revealed STAT5 activation only in FLT3-ITD positive cell lines, in contrast to FLT3-non-ITD mutants, which displayed an enhanced signal of AKT and MAPK activation. Gene expression analysis revealed distinct difference between FLT3-ITD and FLT3-TKD for STAT5 target gene expression as well as deregulation of SOCS2, ENPP2, PRUNE2 and ART3. FLT3-ITD and FLT3 point mutations show a gain-of-function phenotype with distinct signalling properties in vitro. Although poor prognosis in AML is only associated with FLT3-ITD, all activating FLT3 mutations can contribute to leukemogenesis and are thus potential targets for therapeutic interventions.
    PLoS ONE 01/2014; 9(3):e89560. · 3.53 Impact Factor
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    ABSTRACT: The majority of patients with acute myeloid leukemia (AML) who achieve complete remission (CR) relapse with conventional postremission chemotherapy. Allogeneic stem-cell transplantation (alloSCT) might improve survival at the expense of increased toxicity. It remains unknown for which patients alloSCT is preferable. We compared the outcome of 185 matched pairs of a large multicenter clinical trial (AMLCG99). Patients younger than 60 years who underwent alloSCT in first remission (CR1) were matched to patients who received conventional postremission therapy. The main matching criteria were AML type, cytogenetic risk group, patient age, and time in first CR. In the overall pairwise compared AML population, the projected 7-year overall survival (OS) rate was 58% for the alloSCT and 46% for the conventional postremission treatment group (P = .037; log-rank test). Relapse-free survival (RFS) was 52% in the alloSCT group compared with 33% in the control group (P < .001). OS was significantly better for alloSCT in patient subgroups with nonfavorable chromosomal aberrations, patients older than 45 years, and patients with secondary AML or high-risk myelodysplastic syndrome. For the entire patient cohort, postremission therapy was an independent factor for OS (hazard ratio, 0.66; 95% CI, 0.49 to 0.89 for alloSCT v conventional chemotherapy), among age, cytogenetics, and bone marrow blasts after the first induction cycle. AlloSCT is the most potent postremission therapy for AML and is particularly active for patients 45 to 59 years of age and/or those with high-risk cytogenetics.
    Journal of Clinical Oncology 12/2013; · 18.04 Impact Factor
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    ABSTRACT: Cancer cell phenotypes are partially determined by epigenetic specifications such as DNA methylation. Metastasis development is a late event in cancerogenesis and might be associated with epigenetic alterations. An in vivo selection approach was used to generate highly aggressive non-small cell lung cancer (NSCLC) cell lines (A549 and HTB56) followed by genome wide DNA methylation analysis. Furthermore, the therapeutic effects of the epigenetic agent Azacytidine on DNA methylation patterns and the in vivo phenotypes were explored. Widespread changes of DNA methylation were observed during development of highly aggressive cell lines. Up to 2.5% of the CpG rich region was differentially methylated as identified by Reduced Representation Bisulfite Sequencing (RRBS) compared to the less aggressive parental cell lines. DNA methyltransferase inhibition by Azacytidine reversed the pro-metastatic phenotype; this was highly associated with the preferential loss of DNA methylation at sites that were hypermethylated during the in vivo selection. Of note, polycomb (PRC2) binding sites were particularly affected by DNA methylation changes after Azacytidine exposure which persisted over time. We could show that metastatic capability of NSCLC is closely associated with DNA methylome alterations. Since inhibition of DNA methyltransferase reversed metastasis-prone phenotype, epigenetic modulation appears as a potential therapeutic approach to prevent metastasis formation.
    Clinical Cancer Research 12/2013; · 7.84 Impact Factor
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    ABSTRACT: PURPOSE The purpose of this study was to investigate multi-modal USPIO-enhanced MR imaging (MRI), contrast-enhanced Ultrasound (CE-US), 123I-tTF-NGR-SPECT, and Fluorescence Reflectance Imaging (FRI) for early monitoring of anti-vascular treatment effects of the thrombogenic tTF-NGR protein with a specific binding to CD13 on tumor endothelial cells. METHOD AND MATERIALS Fibrosarcoma (HT1080) bearing nude mice (n=12/12/14) were injected with the thrombogenic tTF-NGR with and without earlier blocking of CD13 by pure NGR peptide (GNGRAHA), or saline as control respectively. USPIO-enhanced MRI for determination of the relative blood volume (rBV), 123I-tTF-NGR-SPECT, and FRI for fluorescence imaging of Alexa-Fluor647-labelled fibrinogen were acquired about 4-8 hours after treatment initiation. CE-US was performed during and within 30 minutes after tTF-NGR application. Treatment response and blocking effectiveness were analyzed by histological grading of vascular thrombosis and/or necrosis (score: 0-5). RESULTS MRI revealed a significant reduction of the rBV after tTF-NGR therapy compared to controls (tTF-NGR: 0.710.22% vs. control: 1.670.9%; p<0.05). At blocking experiments, MRI showed various degrees of tumor thrombosis due to differing competitive blocking capacities of the pure NGR peptide. Specimen with an effective blocking of CD13 (as defined by histology; effective = grade 0-2) showed higher rBV values compared to ineffective blocking (NGR block effective: 1.62 ± 0.98% vs. NGR block ineffective: 0.61 ± 0.57). CE-US demonstrated a decrease of the tumor perfusion of approx. 86% within minutes after tTF-NGR application. 123I-tTF-NGR-SPECT demonstrated a selective tracer uptake at the tumor rim. FRI showed clearly thrombosed tumor blood vessels after tTF-NGR therapy. CONCLUSION Multi-modal USPIO-MR, CE-US, SPECT, and FR imaging allow an early complementary assessment of treatment efficacy of the thrombogenic vascular targeting agent tTF-NGR. CLINICAL RELEVANCE/APPLICATION This study demonstrates the feasibility of a complementary early multi-model monitoring of anti-vascular therapies for better understanding of the molecular mechanism of action.
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: Chemo-modulation of cytarabine by fludarabine has been attributed with a higher anti-leukemic efficacy, but randomized trials to address this question are rare. We therefore conducted a multicenter, randomized phase III study to evaluate the antileukemic efficacy of adding fludarabine to sequential high-dose cytarabine+idarubicin (SHAI) re-induction chemotherapy in relapsed or refractory acute myeloid leukemia (AML). Patients (n=326, 281 evaluable) were randomly assigned to SHAI (cytarabine 1 g/m(2) bid days 1-2 and 8-9 [3 g/m(2) for patients60 years with refractory AML or2nd relapse], idarubicin 10 mg/m(2) daily days 3-4 and 10-11) or F-SHAI (SHAI with fludarabine 15 mg/m(2) 4 hours prior to cytarabine). While complete remission (CR) rates (35% SHAI and 44% F-SHAI) and overall survival did not differ between both regimens, fludarabine prolonged time-to-treatment failure from 2.04 months to 3.38 months (median, P<0.05). Twenty-seven percent of patients proceeded to allogeneic SCT, with a significantly higher number of patients in CR or CRi in the F-SHAI group (22% versus 10%, P<0.01). In conclusion, fludarabine has a beneficial though moderate impact on the antileukemic efficacy of high-dose cytarabine based salvage therapy for relapsed and refractory AML.Leukemia accepted article preview online, 22 October 2013; doi:10.1038/leu.2013.297.
    Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 10/2013; · 10.16 Impact Factor
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    ABSTRACT: The fusion protein tTF-NGR consists of the extracellular domain of the thrombogenic human tissue factor (truncated tissue factor, tTF) and the peptide GNGRAHA (NGR), a ligand of the surface protein CD13 (aminopeptidase N), upregulated on endothelial cells of tumor vessels. tTF-NGR preferentially activates blood coagulation within tumor vasculature, resulting in tumor vessel infarction and subsequent tumor growth retardation/regression. The anti-vascular mechanism of the tTF-NGR therapy approach was verified by quantifying the reduced tumor blood-perfusion with contrast-enhanced ultrasound, the reduced relative tumor blood volume by ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance imaging, and by in vivo-evaluation of hemorrhagic bleeding with fluorescent biomarkers (AngioSense(680)) in fluorescence reflectance imaging. The accumulation of tTF-NGR within the tumor was proven by visualizing the distribution of the iodine-123-labelled protein by single-photon emission computed tomography. Use of these multi-modal vascular and molecular imaging tools helped to assess the therapeutic effect even at real time and to detect non-responding tumors directly after the first tTF-NGR treatment. This emphasizes the importance of imaging within clinical studies with tTF-NGR. The imaging techniques as used here have applicability within a wider scope of therapeutic regimes interfering with tumor vasculature. Some even are useful to obtain predictive biosignals in personalized cancer treatment.
    Angiogenesis 10/2013; · 4.41 Impact Factor

Publication Stats

10k Citations
2,842.42 Total Impact Points

Institutions

  • 2001–2014
    • Universitätsklinikum Münster
      • • Medizinische Klinik B
      • • Institut für Humangenetik
      • • Medizinische Klinik und Poliklinik A
      Muenster, North Rhine-Westphalia, Germany
  • 1999–2014
    • University of Münster
      • • Faculty of Medicine
      • • Department of Medicine, Hematology and Oncology
      Muenster, North Rhine-Westphalia, Germany
  • 2012
    • Universität Mannheim
      Mannheim, Baden-Württemberg, Germany
  • 2003–2012
    • Ludwig-Maximilian-University of Munich
      • Department of Internal Medicine II
      München, Bavaria, Germany
  • 2011
    • University Hospital Frankfurt
      Frankfurt, Hesse, Germany
  • 2003–2009
    • University of Hamburg
      • • Department of Stem Cell Transplantation
      • • Center for Oncology
      Hamburg, Hamburg, Germany
  • 2008
    • Universität des Saarlandes
      Saarbrücken, Saarland, Germany
  • 2007
    • Universität Heidelberg
      Heidelburg, Baden-Württemberg, Germany
  • 2006
    • Charité Universitätsmedizin Berlin
      • Department of Pediatrics, Division of Oncology and Hematology
      Berlín, Berlin, Germany
  • 2005
    • Jiangsu University
      • Institute of Life Sciences
      Zhenjiang, Jiangsu Sheng, China
    • Bundeswehrzentralkrankenhaus Koblenz
      Coblenz, Rheinland-Pfalz, Germany
  • 2004
    • University Medical Center Hamburg - Eppendorf
      Hamburg, Hamburg, Germany
  • 2000–2001
    • Cedars-Sinai Medical Center
      • Division of Hematology and Oncology
      Los Angeles, CA, United States
    • California Institute of Technology
      • Division of Biology
      Pasadena, California, United States
  • 1997–1998
    • Max-Delbrück-Centrum für Molekulare Medizin
      Berlín, Berlin, Germany
  • 1991–1998
    • Freie Universität Berlin
      • Department of Hematology
      Berlín, Berlin, Germany
  • 1988–1994
    • Emory University
      • • Department of Hematology and Medical Oncology
      • • Department of Internal Medicine
      • • School of Medicine
      Atlanta, GA, United States
  • 1993
    • University Hospital München
      München, Bavaria, Germany
  • 1981–1993
    • Technische Universität München
      • Medizinische Klinik und Poliklinik I
      München, Bavaria, Germany
  • 1992
    • Roswell Park Cancer Institute
      • Department of Neurosurgery
      Buffalo, New York, United States
  • 1981–1990
    • Deutsches Herzzentrum München
      München, Bavaria, Germany
  • 1986
    • University of Texas Health Science Center at San Antonio
      • Division of Hospital Medicine
      San Antonio, Texas, United States