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Hartmut Döhner

Publications and source records attributed to Hartmut Döhner.

At least 19 recordsLinked to original sources
PubMed2007

Reduced-intensity conditioning followed by T-cell depleted allogeneic stem cell transplantation for patients with chronic myeloid leukaemia and minimal residual disease at the time of transplant: high risk of molecular relapse.

A pilot trial was initiated for chronic myeloid leukaemia patients, which employed imatinib for remission induction, followed by reduced-intensity conditioning and an in vivo T-cell depleted graft. Out of nine patients, six experienced a molecular relapse and one patient had a haematological relapse at a median interval of 5 months after transplantation. Five relapsing patients achieved a 2nd molecular remission after treatment with either donor lymphocyte infusions (n = 4) or imatinib (n = 1). Two of nine patients died due to infectious complications. The probability of survival 2 years after transplant was 74% (95% CI 42-100%).

Adult↗
PubMed2006

Acute myeloid leukaemia.

Acute myeloid leukaemia (AML) is a heterogeneous clonal disorder of haemopoietic progenitor cells and the most common malignant myeloid disorder in adults. The median age at presentation for patients with AML is 70 years. In the past few years, research in molecular biology has been instrumental in deciphering the pathogenesis of the disease. Genetic defects are thought to be the most important factors in determining the response to chemotherapy and outcome. Whereas significant progress has been made in the treatment of younger adults, the prospects for elderly patients have remained dismal, with median survival times of only a few months. This difference is related to comorbidities associated with ageing and to disease biology. Current efforts in clinical research focus on the assessment of targeted therapies. Such new approaches will probably lead to an increase in the cure rate.

Adult↗
PubMed2006

Molecular imaging of proliferation in malignant lymphoma.

We have determined the ability of positron emission tomography (PET) with the thymidine analogue 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) to detect manifestation sites of malignant lymphoma, to assess proliferative activity, and to differentiate aggressive from indolent tumors. In this prospective study, FLT-PET was done additionally to routine staging procedures in 34 patients with malignant lymphoma. Sixty minutes after i.v. injection of approximately 330 MBq FLT, emission and transmission scanning was done. Tracer uptake in lymphoma was evaluated semiquantitatively by calculation of standardized uptake values (SUV) and correlated to tumor grading and proliferation fraction as determined by Ki-67 immunohistochemistry. FLT-PET detected a total of 490 lesions compared with 420 lesions revealed by routine staging. In 11 patients with indolent lymphoma, mean FLT-SUV in biopsied lesions was 2.3 (range, 1.2-4.5). In 21 patients with aggressive lymphoma, a significantly higher FLT uptake was observed (mean FLT-SUV, 5.9; range, 3.2-9.2; P < 0.0001) and a cutoff value of SUV = 3 accurately discriminated between indolent and aggressive lymphoma. Linear regression analysis indicated significant correlation of FLT uptake in biopsied lesions and proliferation fraction (r = 0.84; P < 0.0001). In this clinical study, FLT-PET was suitable for imaging malignant lymphoma and noninvasive assessment of tumor grading. Due to specific imaging of proliferation, FLT may be a superior PET tracer for detection of malignant lymphoma in organs with high physiologic fluorodeoxyglucose uptake and early detection of progression to a more aggressive histology or potential transformation.

Adult↗
PubMed2006

Imatinib impairs CD8+ T lymphocytes specifically directed against the leukemia-associated antigen RHAMM/CD168 in vitro.

The Bcr-Abl tyrosine kinase inhibitor imatinib mesylate is highly effective in the front-line treatment of chronic myeloid leukemia (CML) and is increasingly used in patients with residual disease or relapse after allogeneic stem cell transplantation (allo-SCT). Since an impairment of anti-viral CD8+ T-lymphocyte function by imatinib has been described, we question whether imatinib also affects specific anti-leukemic CD8+ T lymphocytes generated from the peripheral blood of healthy donors, and of CML patients after allo-SCT. Here, we assessed CD8+ T-cell expansion and function from healthy donors and patients with CML. The release of IFN-gamma and granzyme B by CD8+ T-lymphocytes specific for R3, a recently described T-cell epitope peptide derived from a leukemia-associated antigen designated RHAMM/CD168 (receptor for hyaluronic acid mediated motility), was inhibited by imatinib in a dose-dependent fashion (range: 1-25 microM). These T cells were able to lyse cognate peptide labeled T2 cells and CD34+ CML progenitor cells. This lysis was inhibited by imatinib. The inhibitory effect was not associated with an increased rate of apoptosis of T cells and reversible after removal of imatinib. In the light of these findings, clinical administration of imatinib might result in the reduction of efficacy of the graft-versus-leukemia effect or other T-cell-based immunotherapies.

Adult↗
PubMed2006

Disclosure of candidate genes in acute myeloid leukemia with complex karyotypes using microarray-based molecular characterization.

PURPOSE: To identify novel genomic regions of interest in acute myeloid leukemia (AML) with complex karyotypes, we applied comparative genomic hybridization to microarrays (array-CGH), allowing high-resolution genome-wide screening of genomic imbalances. PATIENTS AND METHODS: Sixty AML cases with complex karyotypes were analyzed using array-CGH; parallel analysis of gene expression was performed in a subset of cases. RESULTS: Genomic losses were found more frequently than gains. The most frequent losses affected 5q (77%), 17p (55%), and 7q (45%), and the most frequent genomic gains 11q (40%) and 8q (38%). Critical segments could be delineated to genomic fragments of only 0.8 to a few megabase-pairs of DNA. In lost/gained regions, gene expression profiling detected a gene dosage effect with significant lower/higher average gene expression levels across the genes located in the respective regions. Furthermore, high-level DNA amplifications were identified in several regions: 11q23.3-q24.1 (n = 7), 21q22 (n = 6), 11q23.3 (n = 5), 13q12 (n = 3), 8q24 (n = 3), 9p24 (n = 2), 12p13 (n = 2), and 20q11 (n = 2). Parallel analysis of gene expression in critical amplicons displayed overexpressed candidate genes (eg, C8FW and MYC in 8q24). CONCLUSION: In conclusion, a large spectrum of genomic imbalances, including novel recurring changes in AML with complex karyotypes, was identified using array-CGH. In addition, the combined analysis of array-CGH data with gene expression profiles allowed the detection of candidate genes involved in the pathogenesis of AML.

Acute Disease↗
PubMed2006

Cytogenetics and age are major determinants of outcome in intensively treated acute myeloid leukemia patients older than 60 years: results from AMLSG trial AML HD98-B.

To assess the prognostic impact of cytogenetics in elderly patients with acute myeloid leukemia (AML) receiving intensive induction and consolidation treatment according to a single protocol specifically designed for patients above age 60, pretreatment samples from 361 patients registered for the AML HD98-B trial of the German-Austrian AML Study Group were analyzed by chromosome banding and fluorescence in situ hybridization, and cytogenetic findings were correlated with outcome. Using a proportional hazards model with backward selection, 3 prognostic subgroups were identified based on the influence of cytogenetic abnormalities on overall survival (OS): low-risk, t(15;17), and inv(16) in 25 of 361 patients (7%); standard-risk, normal karyotype, t(8;21), t(11q23), +8 within a noncomplex karyotype, and +11 within a noncomplex karyotype in 208 of 361 patients (58%); high-risk, all other aberrations in 128 of 361 patients (35%). On multivariate analysis, high-risk cytogenetics (hazard ratio [HR], 2.24) and age above 70 years (HR, 2.34) were independent prognostic factors affecting OS, and stratification according to these parameters demonstrated that a large subgroup of patients (55%), characterized by age 70 or older or high-risk cytogenetics, or both, had very unfavorable treatment results despite intensive chemotherapy. Thus, karyotype and age are major determinants of outcome in elderly patients with AML.

Acute Disease↗
PubMed2006

Cytogenetics and molecular cytogenetics in multiple myeloma.

Multiple myeloma (MM) is characterized by frequent and complex genomic abnormalities that not only essentially contribute to the pathogenesis of this disease but also reflect its prognostic heterogeneity. There is evidence for two more or less mutually exclusive oncogenic pathways in the early development of clonal plasma cell disorders. Approximately half the tumours are non-hyperdiploid and carry translocations of the immunoglobulin heavy-chain (IgH) locus and various oncogenes, for example Cyclin D1, Cyclin D3, and FGFR3. The remaining hyperdiploid tumours exhibit recurrent trisomies - typically of chromosomes 5, 7, 9, 11, 15, 19, and 21 - but infrequently exhibit IgH translocations. While some chromosomal aberrations, such as deletion of chromosome arm 13q, deliver independent prognostic information that is already utilized for risk stratification within clinical trials, the prognostic significance of most other genetic aberrations in MM is undetermined.

Chromosome Aberrations↗
PubMed2006

Autologous graft-versus-host disease-like syndrome after an alemtuzumab-containing conditioning regimen and autologous stem cell transplantation for chronic lymphocytic leukemia.

A high incidence of autologous graft-versus-host-disease (auto-GVHD) was observed after an alemtuzumab-containing conditioning regimen and autologous stem cell transplantation (auto-SCT) for chronic lymphocytic leukemia (CLL). Skin rash developed in almost all surviving patients (87%). In 7 patients (58%), a diagnosis of auto-GVHD was made (compared with 0% after TBI/Cy; P = .01). All patients with auto-GVHD required immunosuppression, and 3 of 7 were hospitalized because of GVHD. The median duration of GVHD was 517 days (range, 60-867 days). Auto-GVHD was associated with an abnormally high CD4/CD8 ratio because of severe depletion of CD8(+) T cells, pointing to a potential pathomechanism. High non-relapse-related mortality led to the discontinuation of the trial. Current results do not support the use of high-dose alemtuzumab combined with total body irradiation (TBI) and autologous stem cell transplantation (auto-SCT). However, the addition of alemtuzumab led to improved disease control at the molecular level. Longer follow-up will show whether the GVHD-like syndrome may contribute to prolonged minimal residual disease (MRD) negativity.

Adult↗
PubMed2006

[Clinical research within the German competence net "acute and chronic leukemias"].

BACKGROUND: Leukemias are a challenge and a cost factor to society because of their frequency in all age groups. They also serve as a model for a variety of diseases and possess exemplary relevance for basic research and patient care. Leukemia research and therapy have achieved high standards and even a leading position in Germany with regard to clinical trials, standardization of diagnostics and molecular studies of prognostic factors, signal transduction and gene expression. Progress is hampered, however, by fragmentation of leukemia trial groups, diagnostic approaches and treatment research activities. GOALS: A network was therefore created to integrate the leading leukemia trial groups on chronic myeloid leukemia (CML), acute myeloid leukemia (AML), acute lymphatic leukemia (ALL), myelodysplastic syndromes (MDS) and chronic myeloproliferative diseases (CMPD) and their interdisciplinary partners (diagnostics, treatment research, biometry) in cooperation with basic research and pharmaceutical industry to foster advancements in leukemiarelated research and health care through clinical trials, promotion of translational research, introduction of standards for diagnostics and therapy, and development of evidence-based guidelines. ACHIEVEMENTS: Achievements include establishment of central information, communication and management structures, creation of an AML intergroup comprising five study groups, formation of an MDS study group and establishment of platforms for diagnostics, genomics and proteomics, and medical informatics. Exchange of scientific progress is mediated by intra- and internet, biannual newsletters, regular project group meetings, and annual network symposia. PERSPECTIVES: On the basis of experience with the Competence Network "Acute and chronic leukemias" with its management, communication and information structures, the "European LeukemiaNet" (ELN) has been established within the 6th Framework Program of the European Union. The ELN integrates 78 leading leukemia trial groups (AML, ALL, CML, CLL, MDS, and CMPD), their 83 interdisciplinary partner groups (diagnostics, treatment research, registry, guidelines), industry and SMEs (small- and medium-sized enterprises) across Europe to form a cooperative network for advancements in leukemia-related research and health care.

Acute Disease↗
PubMed2006

Allelic silencing at the tumor-suppressor locus 13q14.3 suggests an epigenetic tumor-suppressor mechanism.

Genomic material from chromosome band 13q14.3 distal to the retinoblastoma locus is recurrently lost in a variety of human neoplasms, indicating an as-yet-unidentified tumor-suppressor mechanism. No pathogenic mutations have been found in the minimally deleted region until now. However, in B cell chronic lymphocytic leukemia tumors with loss of one copy of the critical region, respective candidate tumor-suppressor genes are down-regulated by a factor >2, which would be expected by a normal gene-dosage effect. This finding points to an epigenetic pathomechanism. We find that the two copies of the critical region replicate asynchronously, suggesting differential chromatin packaging of the two copies of 13q14.3. Although we also detect monoallelic silencing of genes localized in the critical region, monoallelic expression originates from either the maternal or paternal copy, excluding an imprinting mechanism. DNA methylation analyses revealed one CpG island of the region to be methylated. DNA demethylation of this CpG island and global histone hyperacetylation induced biallelic expression, whereas replication timing was not affected. We propose that differential replication timing represents an early epigenetic mark that distinguishes the two copies of 13q14.3, resulting in differential chromatin packaging and monoallelic expression. Accordingly, deletion of the single active copy of 13q14.3 results in significant down-regulation of the candidate genes and loss of function, providing a model for the interaction of genetic lesions and epigenetic silencing at 13q14.3 in B cell chronic lymphocytic leukemia.

Adult↗
PubMed2006

Antagonizing inactivated tumor suppressor genes and activated oncogenes by a versatile transgenesis system: application in mantle cell lymphoma.

A broad range of malignant diseases, such as mantle cell lymphoma (MCL), is associated with complex genomic alterations, demanding multimodal functional testing of candidate genes. To assess such candidate disease genes, we have developed a bidirectional targeted transgenesis tool, which allows well-controlled modulation of individual gene activities within a cellular MCL system. The engineered versatile transgenesis system permits functional analysis of virtually any candidate gene: for tumor suppressor genes by complementation via integration of respective genomic DNA or for oncogenes by inactivation via integrated shRNA coding plasmids. Complementation by genomic DNA ensures wild-type (WT) regulated gene expression, whereas genomic integration of shRNA coding inserts by an advanced RNAi-strategy mediates specific knock-down of gene expression. Site-specific genomic integration of an unmodified BAC, which contains the CDKN2A/B genes absent in the MCL model system, restored CDKN2A/B expression resulting in the inhibition of cell proliferation. CCND1, strongly overexpressed in the model system, was down-regulated via shRNA expression, again inhibiting proliferation. Notably, the presented site-specific shRNA-strategy circumvents interference by IFN-response induced when using other RNAi gene knock-down methods. In conclusion, we here demonstrate that adequate restoration of a range of different gene activities yields in a desired antiproliferative effect in MCL-derived cells. By antagonizing inactivated tumor suppressor genes or activated oncogenes, the presented approach can be readily used for the functional analysis of a broad range of disease-related genetic defects.

Cell Line, Tumor↗
PubMed2006

Ala228 variant of trail receptor 1 affecting the ligand binding site is associated with chronic lymphocytic leukemia, mantle cell lymphoma, prostate cancer, head and neck squamous cell carcinoma and bladder cancer.

Allelic loss of chromosome 8p21-22 is a frequent event in various human cancers including mantle cell lymphoma (MCL), prostate cancer, head and neck squamous cell carcinoma (HNSCC) and bladder cancer. The tumor necrosis factor-related apoptosis inducing ligand (TRAIL) receptors, including TNFRSF10A and TNFRSF10B, are located within this chromosomal region. Since recent studies demonstrate that chronic lymphocytic leukemia (CLL) and prostate cells are TRAIL induced apoptosis, TRAIL-receptors are strong tumor suppressor candidate genes in human cancers exhibiting loss of chromosomal material in 8p21.3. However, no mutation of the TRAIL receptor genes has been reported in CLL, MCL, prostate cancer, HNSCC so far. In this study we analyzed the complete coding region of TNFRSF10A and TNFRSF10B in a series of 32 MCL and 101 CLL samples and detected a single nucleotide polymorphism (SNP) in TNFRSF10A (A683C) with tumor specific allele distribution. We examined allele distribution in 395 samples of different tumor entities (prostate cancer, n = 43; HNSCC, n = 40; bladder cancer, n = 179) and compared them to 137 samples from healthy probands. We found the rare allele of TNFRSF10A is more frequent in CLL, MCL, prostate cancer, bladder cancer and HNSCC. The A683C polymorphism did not cosegregate with other TNFRSF10A polymorphisms previously described. Thus screening for 683A-->C nucleotide exchanges may become important in diagnosis and/or treatment of these malignancies.

Binding Sites↗
PubMed2006

Additional genetic high-risk features such as 11q deletion, 17p deletion, and V3-21 usage characterize discordance of ZAP-70 and VH mutation status in chronic lymphocytic leukemia.

PURPOSE: Immunoglobulin heavy chain variable-region (VH) gene mutation status and zeta-associated protein 70 (ZAP-70) expression are correlated in chronic lymphocytic leukemia (CLL), but their concordance is variable. The goal of this study was to elucidate additional factors potentially characterizing their discordance. PATIENTS AND METHODS: We evaluated ZAP-70 expression by flow cytometry, VH status by DNA sequencing, and genomic aberrations by fluorescence in situ hybridization in 148 CLL patients. The parameters were analyzed for their associations and their individual prognostic impact. RESULTS: ZAP-70 expression and VH mutation status were strongly associated in CLL without additional genetic high-risk-features as defined by the absence of 11q or 17p deletion and V3-21 usage (concordance 84%). In contrast, the proportion of discordant cases was significantly higher (39%), if such additional genetic high-risk features were present. Discordant cases with V3-21 usage were almost exclusively ZAP-70 positive and VH mutated (89%), whereas all but one of the discordant cases with high-risk aberrations were ZAP-70 negative and VH unmutated (92%). By multivariate regression analysis, two models were developed, which both include high-risk genomic aberrations and, alternatively, VH mutation status and V3-21 usage or ZAP-70 expression as independent outcome predictors. CONCLUSION: There were characteristic modes of discordance between ZAP-70 and VH mutation status depending on the presence or absence of additional genetic high-risk features such as 11q and 17p deletion or V3-21 usage. Although the biologic background for these findings is yet to be determined, these data have biologic and clinical implications regarding ZAP-70 as a pathogenic factor and outcome predictor, respectively.

Biomarkers, Tumor↗
PubMed2006

Chronic myeloid leukemia cells express tumor-associated antigens eliciting specific CD8+ T-cell responses and are lacking costimulatory molecules.

Specific immunotherapies for patients with chronic myeloid leukemia (CML) might eliminate residual CML cells after therapy with imatinib or chemotherapy and might enhance a specific graft-versus-leukemia effect after allogeneic stem cell transplantation. Here, we investigated the mRNA expression and T-cell recognition of tumor-associated antigens or leukemia-associated antigens (LAAs) in 34 patients with CML. Several LAAs are expressed in CML and therefore are candidate structures for specific immunotherapies: bcr-abl (100%), G250 (24%), hTERT (53%), MPP11 (91%), NEWREN60 (94%), PRAME (62%), Proteinase3 (71%), RHAMM/CD168 (83%), and WT1 (53%), but not BAGE, MAGE-A1, SSX2, or NY-ESO-1. The frequency of mRNA expression of RHAMM/CD168, Proteinase3, and PRAME was higher in acceleration phase and blast crisis. In flow cytometry, CD34+ progenitor cells typed positive for HLA molecules but were deficient for CD40, CD80, CD83, and CD86. However, RHAMM/CD168 R3-peptide (ILSLELMKL)-specific T-cell responses in CML patients were demonstrated by ELISPOT analysis and specific lysis of RHAMM/CD168 R3-pulsed T2 cells and CD34+ CML cells in chromium-51 release assays. RHAMM-R3-specific T cells could be phenotyped as CD8+R3*tetramer+CD45RA+CCR7-CD27- early effector T cells by tetramer staining. Therefore, vaccination strategies inducing such RHAMM-R3-directed effector T cells might be a promising approach to enhance specific immune responses against CML cells.

Adult↗
PubMed2006

Risk stratification in chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) follows an extremely variable clinical course with survival ranging from months to decades. Available treatments can often induce remissions, but eventually all patients relapse. Recently, there has been major progress in the identification of molecular and cellular markers that may predict the tendency for disease progression in patients with CLL. Genomic aberrations, the mutational profile of IgVH genes and its surrogate marker ZAP-70 expression, and serum markers like B2-microglobulin (beta2-MG) and thymidine kinase (TK) provide prognostic information for individual patients independently of clinical disease characteristics. These molecular markers are about to enter the stage of risk stratification for individual patients in clinical trials.

Biomarkers, Tumor↗
PubMed2006

Genetics, gene expression, and targeted therapies in chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) represents the most common leukemia among adults in the Western countries. CLL is a remarkably diverse disorder following an extremely variable clinical course. Some patients have an indolent disease that may never require treatment. In others a progressive clinical course is rapidly fatal. CLL affects mainly elderly individuals, but about a third of patients are less than 60 years of age at diagnosis. Traditionally, the therapeutic procedures were aimed at palliation, but over the recent years highly effective and potentially curative approaches such as combined antibody-chemotherapy and autologous or allogeneic stem cell transplantation have been developed. In parallel there has been progress in the understanding of pathogenesis and outcome prediction. The cornerstones to estimate prognosis are the clinical staging systems of Rai and Binet. To refine outcome prediction for individual patients there has been intensive work on biological factors of potential prognostic relevance. Among these, the genetic characteristics of the CLL cells that can be divided into genomic aberrations and the mutation status of the variable segments of immunoglobulin-heavy chain genes (VH) have attained considerable importance. In addition, data on gene expression of CLL cells are accumulating which further characterize the CLL subgroups. In this context, the expression of ZAP-70 has been recognized a useful surrogate marker to predict the VH mutation status and outcome of CLL patients. At present, targeted therapies are focused on humanized antibodies that bind proteins expressed on the surface of CLL cells. The most prominent agents of these are the anti-CD52 antibody alemtuzumab and the anti-CD20 antibody rituximab, which are currently being tested in clinical trials. To identify CLL-specific gene expression products as candidates for targeted therapies will be an important part of CLL research in the next years.

Animals↗