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1.
Ann Hematol ; 96(12): 1993-2003, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29090343

RESUMO

We describe genetic and clinical characteristics of acute myeloid leukemia (AML) patients according to age from an academic population-based registry. Adult patients with newly diagnosed AML at 63 centers in Germany and Austria were followed within the AMLSG BiO registry (NCT01252485). Between January 1, 2012, and December 31, 2014, data of 3525 patients with AML (45% women) were collected. The median age was 65 years (range 18-94). The comparison of age-specific AML incidence rates with epidemiological cancer registries revealed excellent coverage in patients < 70 years old and good coverage up to the age of 80. The distribution according to the European LeukemiaNet (ELN) risk categorization from 2010 was 20% favorable, 31% intermediate-1, 28% intermediate-2, and 21% adverse. With increasing age, the relative but not the absolute prevalence of patients with ELN favorable and intermediate-1 risk (p < 0.001), with activating FLT3 mutations (p < 0.001), with ECOG performance status < 2 (p < 0.001), and with HCT-CI comorbidity index < 3 (p < 0.001) decreased. Regarding treatment, obesity and favorable risk were associated with an intensive treatment, whereas adverse risk, higher age, and comorbidity index > 0 were associated with non-intensive treatment or best supportive care. The AMLSG BiO registry provides reliable population-based distributions of genetic, clinical, and treatment characteristics according to age.


Assuntos
Leucemia Mieloide Aguda , Mutação , Sistema de Registros , Tirosina Quinase 3 Semelhante a fms , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria , Feminino , Alemanha , Humanos , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
2.
Ann Hematol ; 92(2): 191-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23073603

RESUMO

The majority of patients with myelodysplastic syndrome (MDS) present with anemia and will become dependent on regular transfusions of packed red blood cells (PRBC) with the risk of iron overload (IOL). Liver iron content best reflects the total body iron content, and measurement of liver iron concentration (LIC) by MRI is a validated tool for detection, but data in MDS is rather limited. Here we present the results of a multi-center trial evaluating the efficacy and safety of deferasirox (DFX) in low and intermediate-1 risk MDS patients with transfusion-dependent IOL. Three patients with transfusion frequency of > 4 units PRBC per month were initially treated with 30 mg/kg/day while in 46 patients with a lower transfusion burden deferasirox was initiated at 20 mg/kg/day, due to patient related reasons one patient received DFX in a dose of 6 mg/kg/day only. LIC was measured by MRI at baseline and end of study using the method by St. Pierre et al. The intention to treat population consisted of 50 MDS patients (28 male; 22 female) with a median age of 69 years who were treated with DFX for a median duration of 354 days. Mean daily dose of DFX was 19 mg/kg/day. Median serum ferritin level (SF) at baseline was 2,447 ng/mL and decreased to 1,685 ng/mL (reduction by 31 %) at end of study (p = 0.01). In 7 (13 %) patients the initially chosen dose had to be increased due to unsatisfactory efficacy of chelation therapy. For 21 patients, LIC measurement by liver MRI was performed at baseline and for 19 of these patients at the end of study: mean LIC decreased significantly from 16,8 mg/g dry tissue weight (± 8.3 mg/g dry tissue weight) at study entry to 10,8 mg/g dry tissue weight (± 10.4 mg/g dry tissue weight) at end of study (p = 0.01). Of all patients exposed to the study drug (n = 54), 28 (52 %) did not complete the 12 month study period most commonly due to AEs in 28 % (n = 15) and abnormal laboratory values in 7 % (n = 4), respectively. The most common adverse events (≥ 10 % of all patients) with suspected drug relationship were diarrhea (n = 25, 46 %), nausea (n = 13, 24 %), upper abdominal pain (n = 8, 15 %), serum creatinine increase (n = 16, 30 %) and rash (n = 5, 9 %). Adverse events making dose adjustments or interruption of study drug necessary occurred in 33 patients (61 %). Hematologic improvement according to IWG criteria (2006) was observed in 6 patients (11 %). Initiation of treatment of IOL with DFX depending on the transfusion burden yields sufficient reduction of excess iron indicated by serum ferritin levels and most importantly by liver MRI. The safety profile of DFX was comparable to previous observations.


Assuntos
Benzoatos/uso terapêutico , Terapia por Quelação , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Síndromes Mielodisplásicas/terapia , Reação Transfusional , Triazóis/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Terapia por Quelação/efeitos adversos , Creatinina/sangue , Deferasirox , Toxidermias/etiologia , Feminino , Ferritinas/sangue , Gastroenteropatias/induzido quimicamente , Humanos , Ferro/análise , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Fígado/química , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/epidemiologia , Risco , Resultado do Tratamento , Triazóis/administração & dosagem , Triazóis/efeitos adversos
3.
BMC Med Genomics ; 14(1): 166, 2021 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174884

RESUMO

BACKGROUND: Repeat elements constitute a large proportion of the human genome and recent evidence indicates that repeat element expression has functional roles in both physiological and pathological states. Specifically for cancer, transcription of endogenous retrotransposons is often suppressed to attenuate an anti-tumor immune response, whereas aberrant expression of heterochromatin-derived satellite RNA has been identified as a tumor driver. These insights demonstrate separate functions for the dysregulation of distinct repeat subclasses in either the attenuation or progression of human solid tumors. For hematopoietic malignancies, such as Acute Myeloid Leukemia (AML), only very few studies on the expression/dysregulation of repeat elements were done. METHODS: To study the expression of repeat elements in AML, we performed total-RNA sequencing of healthy CD34 + cells and of leukemic blast cells from primary AML patient material. We also developed an integrative bioinformatic approach that can quantify the expression of repeat transcripts from all repeat subclasses (SINE/ALU, LINE, ERV and satellites) in relation to the expression of gene and other non-repeat transcripts (i.e. R/G ratio). This novel approach can be used as an instructive signature for repeat element expression and has been extended to the analysis of poly(A)-RNA sequencing datasets from Blueprint and TCGA consortia that together comprise 120 AML patient samples. RESULTS: We identified that repeat element expression is generally down-regulated during hematopoietic differentiation and that relative changes in repeat to gene expression can stratify risk prediction of AML patients and correlate with overall survival probabilities. A high R/G ratio identifies AML patient subgroups with a favorable prognosis, whereas a low R/G ratio is prevalent in AML patient subgroups with a poor prognosis. CONCLUSIONS: We developed an integrative bioinformatic approach that defines a general model for the analysis of repeat element dysregulation in physiological and pathological development. We find that changes in repeat to gene expression (i.e. R/G ratios) correlate with hematopoietic differentiation and can sub-stratify AML patients into low-risk and high-risk subgroups. Thus, the definition of a R/G ratio can serve as a valuable biomarker for AML and could also provide insights into differential patient response to epigenetic drug treatment.


Assuntos
Leucemia Mieloide Aguda
4.
Leukemia ; 35(3): 835-849, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32595214

RESUMO

In the current World Health Organization (WHO)-classification, therapy-related myelodysplastic syndromes (t-MDS) are categorized together with therapy-related acute myeloid leukemia (AML) and t-myelodysplastic/myeloproliferative neoplasms into one subgroup independent of morphologic or prognostic features. Analyzing data of 2087 t-MDS patients from different international MDS groups to evaluate classification and prognostication tools we found that applying the WHO classification for p-MDS successfully predicts time to transformation and survival (both p < 0.001). The results regarding carefully reviewed cytogenetic data, classifications, and prognostic scores confirmed that t-MDS are similarly heterogeneous as p-MDS and therefore deserve the same careful differentiation regarding risk. As reference, these results were compared with 4593 primary MDS (p-MDS) patients represented in the International Working Group for Prognosis in MDS database (IWG-PM). Although a less favorable clinical outcome occurred in each t-MDS subset compared with p-MDS subgroups, FAB and WHO-classification, IPSS-R, and WPSS-R separated t-MDS patients into differing risk groups effectively, indicating that all established risk factors for p-MDS maintained relevance in t-MDS, with cytogenetic features having enhanced predictive power. These data strongly argue to classify t-MDS as a separate entity distinct from other WHO-classified t-myeloid neoplasms, which would enhance treatment decisions and facilitate the inclusion of t-MDS patients into clinical studies.


Assuntos
Biomarcadores Tumorais/análise , Síndromes Mielodisplásicas/classificação , Síndromes Mielodisplásicas/diagnóstico , Segunda Neoplasia Primária/classificação , Segunda Neoplasia Primária/diagnóstico , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/terapia , Segunda Neoplasia Primária/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
J Exp Med ; 167(3): 873-86, 1988 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3280726

RESUMO

The p53 is a nuclear protein that is associated with normal cellular proliferation and can cooperate with Ha-ras in causing cellular transformation in vitro. Lineage association is known to exist between p53 expression and normal lymphopoiesis, but not myelopoiesis. We studied the expression of p53 using chronic myelogenous leukemia (CML) cell lines, somatic hybrids of these cells, and leukemic cells from CML patients. Lymphoid CML lines expressed both p53 mRNA and protein. We also analyzed p53 synthesis by two B-lymphoid lines from the same CML patient; cells of one line were derived from the neoplastic clone, cells of the other were derived from the normal clone. Both synthesized equal amounts of a phosphorylated p53 protein. None of the myeloid CML lines expressed detectable p53 protein and two of four expressed negligible p53 mRNA. Two other myeloid CML lines and myeloid cells from three of four patients expressed p53 mRNA. These findings suggest that expression of the gene is not regulated normally in CML. Several approaches were pursued to explore the differential expression of p53. Southern blot analyses showed no gross alterations in the p53 gene from cells of either the expressing or the nonexpressing lines. No difference in the pattern of demethylated CpG sites was noted in the region of the p53 gene in cells from K562 (myeloid p53 nonexpressor) and in BV173 (lymphoid p53 expressor). The sites of demethylation clustered in and around the p53 promoter in both cell lines. Somatic hybrids formed between a p53 mRNA nonexpressor myeloid line (K562) and the parental p53 expressor lymphoid lines (Daudi, PUT) produced p53 mRNA and protein, suggesting that p53 is a dominantly expressed protein and that lack of expression in myeloid cells is not mediated by a trans-acting negative regulatory protein. DNA transfection experiments performed using the indicator gene chloramphenicol acetyltransferase attached to promoter sequences of p53 showed that these constructs were equally activated in BV173 (p53 expressor) and K562 (p53 mRNA nonexpressor). The mechanism of p53 regulation in CML remains unclear.


Assuntos
Leucemia Mieloide/metabolismo , Proteínas de Neoplasias/biossíntese , Fosfoproteínas/biossíntese , Crise Blástica/metabolismo , DNA de Neoplasias/análise , Regulação da Expressão Gênica , Humanos , Células Híbridas/análise , Leucemia Mieloide/genética , Metilação , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/biossíntese , Células Tumorais Cultivadas/análise , Proteína Supressora de Tumor p53
6.
J Exp Med ; 171(5): 1785-90, 1990 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1692082

RESUMO

In this paper we demonstrate that maturing neoplastic cells from patients with chronic myelogenous leukemia (CML) constitutively produce G-CSF and are also receptive for this molecule. G-CSF functions as an autocrine growth factor in stable phase CML, and thus is responsible for divisions of maturing leukemic cells leading to an expansion of the compartment of mature cells. This observation is well in line with in vivo features of CML in stable phase, i.e., the hyperplasia of the mature granulocyte compartment. In acute blastic phase of CML expression of the G-CSF gene seems to be less common and not related to autonomous blast growth.


Assuntos
Divisão Celular , Fatores Estimuladores de Colônias/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Linfócitos/imunologia , Antígenos CD/análise , Medula Óssea/patologia , Fatores Estimuladores de Colônias/biossíntese , Fatores Estimuladores de Colônias/fisiologia , DNA de Neoplasias/genética , Fator Estimulador de Colônias de Granulócitos , Antígenos HLA-DR/análise , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Linfócitos/patologia , Sondas RNA , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Neoplásico/genética
7.
Ann Oncol ; 21(1): 120-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19605511

RESUMO

BACKGROUND: The International Prognostic Scoring System (IPSS) is the golden standard to assess prognosis in myelodysplastic syndromes (MDS). The aim of this analysis was to study age and gender as interacting variables for individualized prognostication. PATIENTS AND METHODS: In all, 897 patients with primary MDS treated with supportive care only were examined in a retrospective multicenter study. A Cox model was developed to determine the prognostic impact of age and gender on survival and to examine their modulating influence on IPSS results. Based on main effects and interactions of these variables, we established an individualized age- and gender-adapted scoring system to improve prognostication in MDS. RESULTS: While the risk of a patient in the IPSS is best represented by the values 0 (low), +1 (intermediate-1), +2 (intermediate-2), and +3 (high), these values were found to vary between -1.9 and +3.5 in the same patients when including age and gender. Whereas in low-risk MDS, male patients were found to have a less favorable survival, a particularly high risk (+3.5) was found in younger (< or = 66 years) high-risk female patients. CONCLUSION: The inclusion of age and gender and their respective interactions contribute to improved and individualized prognostication in MDS.


Assuntos
Síndromes Mielodisplásicas/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores Sexuais , Adulto Jovem
8.
Recent Results Cancer Res ; 184: 215-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20072841

RESUMO

Human Polo-like kinase 1 (Plk1) is an essential regulator of mitotic progression. Targeted inhibition of this kinase was effective in killing tumor cells in vitro and in vivo. The Plk1 inhibitor BI_2536 was well tolerated and showed antitumor activity in the first clinical trials enrolling patients with advanced solid tumors and refractory or relapsed acute myeloid leukemia.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Pteridinas/uso terapêutico , Animais , Ensaios Clínicos como Assunto , Humanos , Pteridinas/farmacologia , Quinase 1 Polo-Like
9.
Ann Hematol ; 88(4): 319-24, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18784923

RESUMO

The 21-kD protein Ras of the low-molecular-weight GTP-binding (LMWG) family plays an important role in transduction of extracellular signals. Ras functions as a 'molecular switch' in transduction of signals from the membrane receptors of many growth factors, cytokines, and other second messengers to the cell nucleus. Numerous studies have shown that in multiple malignant tumors and hematopoietic malignancies, faulty signal transduction via the Ras pathway plays a key role in tumorigenesis. In this work, a non-radioactive assay was used to quantify Ras activity in hematologic malignancies. Ras activation was measured in six different cell lines and 24 patient samples, and sequence analysis of N- and K-ras was performed. The 24 patient samples comprised of seven acute myelogenous leukemia (AML) samples, five acute lymphocytic leukemia (ALL) samples, four myeloproliferative disease (MPD) samples, four lymphoma samples, four juvenile myelomonocytic leukemia (JMML) samples, and WBC from a healthy donor. The purpose of this study was to compare Ras activity determined by percentage of Ras-GTP with the mutational status of the Ras gene in the hematopoietic cells of the patients. Mutation analysis revealed ras mutations in two of the seven AML samples, one in codon 12 and one in codon 61; ras mutations were also found in two of the four JMML samples, and in one of the four lymphoma samples (codon 12). We found a mean Ras activation of 23.1% in cell lines with known constitutively activating ras mutations, which was significantly different from cell lines with ras wildtype sequence (Ras activation of 4.8%). Two of the five activating ras mutations in the patient samples correlated with increased Ras activation. In the other three samples, Ras was probably activated through "upstream" or "downstream" mechanisms.


Assuntos
Neoplasias Hematológicas/química , Neoplasias Hematológicas/genética , Proteínas ras/análise , Proteínas ras/genética , Análise Mutacional de DNA , Guanosina Difosfato/análise , Guanosina Trifosfato/análise , Neoplasias Hematológicas/etiologia , Humanos , Leucemia Mieloide Aguda , Leucemia Mielomonocítica Juvenil , Linfoma , Mutação , Transtornos Mieloproliferativos , Oncogenes , Leucemia-Linfoma Linfoblástico de Células Precursoras , Transdução de Sinais/genética , Células Tumorais Cultivadas
11.
Leuk Res ; 32(4): 587-91, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17881052

RESUMO

Chronic myelomonocytic leukemia (CMML) characterized by cytopenias, bone marrow and peripheral blood cell dysplasia is notoriously hard to treat. Recent reclassification of CMML as a myelodysplastic/myeloproliferative (MDS/MPS) disease rather than a myelodysplastic syndrome (MDS) by the World Health Organisation (WHO) has led to a review of CMML patients treated with decitabine. Overall response rates (ORR) (complete response [CR]+partial response [PR]) in the subset of patients with CMML in one pivotal phase 3 trial (D-0007) and two phase 2 trials (PCH 95-11, PCH 97-19) decitabine were reviewed. For consistency across trials, all decitabine-treated patients were evaluated using the phase 2 response criteria (CR was defined by normocellular bone marrow with <5% blasts and normal Hgb, WBC, and platelet counts, and PR required 50% decrease in blast count, increases in Hgb by >1.5 mmol/L, WBC count by >1000, and platelet count by >50,000). A total of 31 patients diagnosed with CMML are included in this review. Similar demographics and disease characteristics were observed in all three studies, with an average age of 70.2 years and 71% of patients male. Baseline WBC of >20,000 were observed in 8/28 (29%) patients and baseline bone marrow blasts >5% in 11/28 (39%) patients. All clinical responses were centrally reviewed. The ORR was 25% (14% CR+11% PR). Hematologic improvement was observed in 11% of patients and stable disease in 39% of patients. The decitabine adverse event profile seen in CMML patients was similar to observations in other hematologic patient populations, with myelosuppression and related infectious complications. These data demonstrate encouraging activity for decitabine in CMML, and suggest that studies in other myeloproliferative diseases may be warranted.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/análogos & derivados , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Azacitidina/uso terapêutico , Medula Óssea/patologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Análise Citogenética , Decitabina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Resultado do Tratamento
12.
Leukemia ; 21(3): 411-20, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17252013

RESUMO

Ligands specifically binding to leukemia cells may be used for drug targeting, resulting in more effective treatment with less side effects. Little is known about receptors specifically expressed on acute myeloid leukemia (AML) cells or ligands thereof. We selected random phage display peptide libraries on Kasumi-1 AML cells. A peptide with the sequence CPLDIDFYC was enriched. Phage displaying this peptide strongly bound to Kasumi-1 and SKNO-1 cells and binding could be inhibited by the cognate peptide. Both, Kasumi-1 and SKNO-1 cells carry the chromosomal translocation t(8;21), leading to aberrant expression of the fusion protein AML1/ETO. CPLDIDFYC also strongly and specifically bound primary AML1/ETO-positive AML blasts as well as U-937 cells with forced AML1/ETO expression, suggesting that the CPLDIDFYC receptor may be upregulated upon AML1/ETO expression. Gene expression profiling comparing a panel of CPLDIDFYC-binding and CPLDIDFYC-nonbinding cell lines identified a set of potential receptors for the CPLDIDFYC peptide. Further analysis suggested that alpha4beta1 integrin (VLA-4) is the CPLDIDFYC receptor. Finally, we showed that the CPLDIDFYC-phage is internalized upon receptor binding, suggesting that the CPLDIDFYC-receptor-ligand interaction may be exploitable for targeting drugs or gene therapy vectors to leukemia cells carrying the suitable receptor.


Assuntos
Integrina alfa4beta1/metabolismo , Leucemia Mieloide/patologia , Oligopeptídeos/farmacologia , Biblioteca de Peptídeos , Doença Aguda , Idoso , Linhagem Celular Tumoral/metabolismo , Cromossomos Humanos Par 21/genética , Cromossomos Humanos Par 21/ultraestrutura , Cromossomos Humanos Par 8/genética , Cromossomos Humanos Par 8/ultraestrutura , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Endocitose , Feminino , Perfilação da Expressão Gênica , Terapia Genética , Humanos , Integrina alfa4beta1/antagonistas & inibidores , Leucemia Mieloide/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Ligantes , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/metabolismo , Oligopeptídeos/isolamento & purificação , Oligopeptídeos/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/fisiologia , Ligação Proteica , Proteína 1 Parceira de Translocação de RUNX1 , Receptores de Droga/antagonistas & inibidores , Receptores de Droga/metabolismo , Translocação Genética
13.
Oncogene ; 25(9): 1349-57, 2006 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-16247445

RESUMO

A 117 bp fragment of the human ELA2 promoter has been characterized that can act as a minimal promoter for the expression of neutrophil elastase. Chromatin immunoprecipitation and siRNAs revealed that expression of ELA2 is regulated by the acute myeloid human leukemia 1 protein (AML1), C/EBPalpha, PU.1 and c-Myb transcription factors. ELA2 has also been investigated as a possible target of the leukemic fusion protein AML1-ETO resulting from the t(8;21) chromosomal translocation. AML1-ETO, like AML1, binds the ELA2 promoter in the myeloid cell lines Kasumi-1 and U937, but unexpectedly fails to significantly alter expression of ELA2. Although AML1-ETO downregulates the expression of C/EBPalpha, changes in C/EBPalpha expression do not correlate with changes in the expression of ELA2. Our observations indicate that AML1-ETO may not be a constitutive repressor of gene expression in every case in which it can associate with DNA, either on its own or in conjunction with C/EBPalpha. Since neither ETO nor AML1-ETO are typically expressed in hematopoietic progenitors, we hypothesize that it is the interactions between AML1-ETO and regulatory cofactors in disease-state cells that alter gene expression programs during hematopoiesis. These protein-protein interactions may not require simultaneous DNA binding by AML1-ETO for the deleterious effects of the fusion protein to be realized.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Regulação Neoplásica da Expressão Gênica , Proteínas de Fusão Oncogênica/fisiologia , RNA Interferente Pequeno , Serina Endopeptidases/biossíntese , Fatores de Transcrição/fisiologia , Doença Aguda , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA , Hematopoese/genética , Humanos , Leucemia Mieloide/genética , Regiões Promotoras Genéticas , Proteína 1 Parceira de Translocação de RUNX1 , Serina Endopeptidases/genética
14.
Leukemia ; 20(1): 115-21, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16307025

RESUMO

The demethylating agents 5-azacytidine and 5-aza-2'-deoxycytidine (DAC) have been shown to induce differentiation and inhibit growth of leukemic myeloid cells at low concentrations. However, the effect of DAC in changing the differentiation and proliferation behavior of normal human myeloid progenitors has rarely been investigated. Therefore, we established an in vitro model of normal hematopoietic differentiation, using CD34+ cells from mobilized peripheral blood, to study proliferation and colony formation, expression of several myeloid maturation markers and of the inhibitor of cyclin-dependent kinases p15/INK4b. Upon DAC treatment, cell growth was significantly decreased in a dose-dependent manner, without an increase in cytotoxicity. DAC treatment also resulted in a substantial increase of lysozyme-positive cells, which could be enhanced by G-CSF, a modest increase of myeloperoxidase+ and CD15+ cells, as well as an increase of colony-forming cells (CFU-GM) compared to control cells. p15/INK4b protein expression was strongly upregulated upon myeloid maturation, and additional DAC treatment did not change p15 expression or the methylation status of the p15 promoter at the noncytotoxic concentrations used. Taken together, these data indicate a role of DAC in changing myeloid progenitor cell expansion and differentiation. This model appears suitable also for global analyses of multiple differentially methylated genes.


Assuntos
Azacitidina/análogos & derivados , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Antígenos CD34/biossíntese , Antígenos CD34/metabolismo , Azacitidina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p15/efeitos dos fármacos , Decitabina , Relação Dose-Resposta a Droga , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Muramidase/biossíntese , Muramidase/efeitos dos fármacos , Muramidase/metabolismo
15.
Leukemia ; 20(6): 987-93, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16598301

RESUMO

AML1-ETO, a leukemia-associated fusion protein generated by the frequently occurred chromosome translocation t(8;21) in acute myeloid leukemia, was shown to exert dichotomous functions in leukemic cells, that is, growth arrest versus differentiation block. By the analysis of oligonucleotide microarray, AML1-ETO was shown to modulate the expressions of an impressive array of pro- and anti-apoptotic genes. Here, we investigate potential effects of the ecdysone inducible AML1-ETO expression on apoptosis of leukemic U937 cell line. We show that AML1-ETO significantly stabilizes death receptor Fas protein and increases proapoptotic Bak in addition to reducing Bcl-2 expression. Accordingly, inducible AML1-ETO expression is followed by apoptosis to a lower degree. Especially, AML1-ETO endows leukemic cells with the susceptibility to anti-Fas agonist antibody, ultraviolet light and camptothecin analog NSC606985-induced apoptosis with increased activation of caspase-3/8. Considering that apoptosis-enhancing effect of AML1-ETO would not be favorable to the leukemogenesis harboring the t(8;21) translocation, it must be overcome to fulfill their leukemogenic potential. Complementary to this prediction is that two AML1-ETO-carrying leukemic cells, Kasumi-1 and SKNO-1, present similar sensitivity to apoptosis induction with AML1-ETO-negative leukemic cells. Therefore, genetic and/or epigenetic screenings of apoptosis-related genes modulated by AML1-ETO deserve to be explored for understanding the mechanisms of AML1-ETO-induced leukemogenesis.


Assuntos
Apoptose/efeitos dos fármacos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Proteínas de Fusão Oncogênica/genética , Anticorpos Monoclonais , Apoptose/genética , Apoptose/efeitos da radiação , Western Blotting , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/efeitos dos fármacos , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Cicloeximida/farmacologia , Ecdisterona/análogos & derivados , Ecdisterona/farmacologia , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Fusão Oncogênica/efeitos dos fármacos , Proteínas de Fusão Oncogênica/metabolismo , RNA Mensageiro/genética , Proteína 1 Parceira de Translocação de RUNX1 , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fatores de Tempo , Raios Ultravioleta , Receptor fas
16.
Eur J Cancer ; 86: 233-239, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29055209

RESUMO

BACKGROUND: Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD)-positive acute myeloid leukaemia (AML) relapsing after allogeneic stem cell transplantation (allo-SCT) has a dismal prognosis with limited therapeutic options. FLT3-ITD kinase inhibition is a reasonable but palliative experimental treatment alternative in this situation. Information on long-term outcome is not available. METHODS: We performed a long-term follow-up analysis of a previously reported cohort of 29 FLT3-ITD-positive AML patients, which were treated in relapse after allo-SCT with sorafenib monotherapy. FINDINGS: With a median follow-up of 7.5 years, 6 of 29 patients (21%) are still alive. Excluding one patient who received a second allo-SCT, five patients (17%) achieved sustained complete remissions with sorafenib. Four of these patients are in treatment-free remission for a median of 4.4 years. INTERPRETATION: Sorafenib may enable cure of a proportion of very poor risk FLT3-ITD-positive AML relapsing after allo-SCT.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Leucemia Mieloide Aguda/terapia , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Transplante de Células-Tronco/efeitos adversos , Sequências de Repetição em Tandem , Tirosina Quinase 3 Semelhante a fms/genética , Adolescente , Adulto , Idoso , Antineoplásicos/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Feminino , Alemanha , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Niacinamida/efeitos adversos , Niacinamida/uso terapêutico , Compostos de Fenilureia/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Recidiva , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Sorafenibe , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
17.
Leukemia ; 31(6): 1286-1295, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27881874

RESUMO

We studied acute myeloid leukemia (AML) patients with lympho-myeloid clonal hematopoiesis (LM-CH), defined by the presence of DNA methyltransferase 3A (DNMT3A) mutations in both the myeloid and lymphoid T-cell compartment. Diagnostic, complete remission (CR) and relapse samples were sequenced for 34 leukemia-related genes in 171 DNMT3A mutated adult AML patients. AML with LM-CH was found in 40 patients (23%) and was associated with clonal hematopoiesis of indeterminate potential years before AML, older age, secondary AML and more frequent MDS-type co-mutations (TET2, RUNX1 and EZH2). In 82% of AML patients with LM-CH, the preleukemic clone was refractory to chemotherapy and was the founding clone for relapse. Both LM-CH and non-LM-CH MRD-positive AML patients who achieved CR had a high risk of relapse after 10 years (75% and 75%, respectively) compared with patients without clonal hematopoiesis in CR with negative MRD (27% relapse rate). Long-term survival of patients with LM-CH was only seen after allogeneic hematopoietic stem cell transplantation (HSCT). We define AML patients with LM-CH as a distinct high-risk group of AML patients that can be identified at diagnosis through mutation analysis in T cells and should be considered for HSCT.


Assuntos
Células Clonais , Hematopoese , Leucemia Mieloide Aguda/patologia , Células Progenitoras Linfoides/patologia , Células Progenitoras Mieloides/patologia , Recidiva Local de Neoplasia/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Terapia Combinada , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Resistencia a Medicamentos Antineoplásicos , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Células Progenitoras Linfoides/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Células Progenitoras Mieloides/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Adulto Jovem
18.
Blood Cancer J ; 7(5): e564, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28548643

RESUMO

The aim of this cohort study was to compare a condensed schedule of consolidation therapy with high-dose cytarabine on days 1, 2 and 3 (HDAC-123) with the HDAC schedule given on days 1, 3 and 5 (HDAC-135) as well as to evaluate the prophylactic use of pegfilgrastim after chemotherapy in younger patients with acute myeloid leukemia in first complete remission. One hundred and seventy-six patients were treated with HDAC-135 and 392 patients with HDAC-123 with prophylactic pegfilgrastim at days 10 and 8, respectively, in the AMLSG 07-04 and the German AML Intergroup protocol. Time from start to chemotherapy until hematologic recovery with white blood cells >1.0 G/l and neutrophils >0.5 G/l was in median 4 days shorter in patients receiving HDAC-123 compared with HDAC-135 (P<0.0001, each), and further reduced by 2 days (P<0.0001) by pegfilgrastim. Rates of infections were reduced by HDAC-123 (P<0.0001) and pegfilgrastim (P=0.002). Days in hospital and platelet transfusions were significantly reduced by HDAC-123 compared with HDAC-135. Survival was neither affected by HDAC-123 versus HDAC-135 nor by pegfilgrastim. In conclusion, consolidation therapy with HDAC-123 leads to faster hematologic recovery and less infections, platelet transfusions as well as days in hospital without affecting survival.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimioterapia de Consolidação/métodos , Citarabina/administração & dosagem , Filgrastim/administração & dosagem , Leucemia Mieloide Aguda , Transfusão de Plaquetas , Polietilenoglicóis/administração & dosagem , Adolescente , Adulto , Daunorrubicina/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Tempo de Internação , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
19.
Leukemia ; 31(6): 1306-1313, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28138160

RESUMO

We evaluated the impact of salvage regimens and allogeneic hematopoietic cell transplantation (allo-HCT) in acute myeloid leukemia (AML) with induction failure. Between 1993 and 2009, 3324 patients with newly diagnosed AML were enrolled in 5 prospective treatment trials of the German-Austrian AML Study Group. After first induction therapy with idarubicin, cytarabine and etoposide (ICE), 845 patients had refractory disease. In addition, 180 patients, although responding to first induction, relapsed after second induction therapy. Of the 1025 patients with induction failure, 875 (median age 55 years) received intensive salvage therapy: 7+3-based (n=59), high-dose cytarabine combined with mitoxantrone (HAM; n=150), with all-trans retinoic acid (A; A-HAM) (n=247), with gemtuzumab ozogamicin and A (GO; GO-A-HAM) (n=140), other intensive regimens (n=165), experimental treatment (n=27) and direct allo-HCT (n=87). In patients receiving intensive salvage chemotherapy (n=761), response (complete remission/complete remission with incomplete hematological recovery (CR/CRi)) was associated with GO-A-HAM treatment (odds ratio (OR), 1.93; P=0.002), high-risk cytogenetics (OR, 0.62; P=0.006) and age (OR for a 10-year difference, 0.75; P<0.0001). Better survival probabilities were seen in an extended Cox regression model with time-dependent covariables in patients responding to salvage therapy (P<0.0001) and having the possibility to perform an allo-HCT (P<0.0001). FLT3 internal tandem duplication, mutated IDH1 and adverse cytogenetics were unfavorable factors for survival.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/mortalidade , Leucemia Mieloide Aguda/mortalidade , Recidiva Local de Neoplasia/mortalidade , Terapia de Salvação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida , Transplante Homólogo , Adulto Jovem
20.
Leuk Res ; 30(8): 1043-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16464494

RESUMO

Distinct morphologic and clinical features associated with specific chromosomal abnormalities have been described in subgroups of myelodysplastic syndromes (MDS), which often are losses or gains and only rarely translocations. Among 103 consecutive MDS patients diagnosed and karyotyped at the Albert-Ludwigs University of Freiburg (ALU) between 1993 and 1999, two chronic myelomonocytic leukemias (CMMoL) displayed trisomy 19 (+19) as the sole chromosomal abnormality. Three further CMMoL cases with +19 as the single abnormality, two of which previously reported, were collected from other centers. Four of the five patients presented with leukocytosis and splenomegaly, and an increased number of ringed sideroblasts was observed in two cases. Treatment was low-dose Decitabine (cases 1 and 2), oral steroids (case 3), hydroxyurea (case 4), and daunorubicin/Ara-C (case 5). Transformation to acute myeloid leukemias (AML) occurred in three/five patients (cases 1, 2, and 4) 26, 12, and 22 months after diagnosis of CMMoL, respectively. We conclude that +19 as the sole anomaly is a rare but recurrent change in CMMoL, in particular of the proliferative type. It is at present unclear which gene(s) located on chromosome 19 might have a functional role for the development of this phenotype.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 19/genética , Leucemia Mielomonocítica Crônica/genética , Síndromes Mielodisplásicas/genética , Idoso , Azacitidina/análogos & derivados , Azacitidina/uso terapêutico , Citarabina/uso terapêutico , Análise Citogenética/métodos , Daunorrubicina/uso terapêutico , Decitabina , Relação Dose-Resposta a Droga , Evolução Fatal , Feminino , Humanos , Hidroxiureia/uso terapêutico , Leucemia Mielomonocítica Crônica/diagnóstico , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/tratamento farmacológico , Fenótipo , Esteroides/uso terapêutico , Resultado do Tratamento
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