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1.
Blood ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484648

RESUMO

Germline DDX41 mutations are involved in familial myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML). We analyzed the prevalence and characteristics of DDX41-related myeloid malignancies in an unselected cohort of 1385 patients with MDS or AML. Using targeted next-generation sequencing, we identified 28 different germline DDX41 variants in 43 unrelated patients which we classified as causal (n=21) or unknown significance (n=7) variants. We focused on the 33 patients having causal variants, representing 2.4% of our cohort. Median age was 69 years, most patients were males (79%). Only 9 patients (27%) had a family history of hematological malignancy, while 15 (46%) had personal history of cytopenias years prior to MDS/AML diagnosis. Most patients had normal karyotype (85%) and the most frequent somatic alteration was a second DDX41 mutation (79%). High-risk DDX41 MDS/AML patients treated with intensive chemotherapy (n=9) or azacitidine (n=11) had an overall response rate of 100% and 73%, respectively, with a median overall survival of 5.2 years. Our study highlights that germline DDX41 mutations are relatively common in adult MDS/AML, often without known family history, arguing for systematic screening. Salient features of DDX41-related myeloid malignancies include male preponderance, frequent pre-existing cytopenias, additional somatic DDX41 mutation and relatively good outcome.

2.
Haematologica ; 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31278207

RESUMO

Iron overload due to red blood cell transfusions is associated with morbidity and mortality in lower-risk myelodysplastic syndrome patients. Many studies suggested improved survival after iron chelation therapy, but valid data are limited. The aim of this study was to assess the effect of iron chelation on overall survival and hematological improvement in lower-risk myelodysplastic syndrome patients in the European MDS registry. We compared chelated patients with a contemporary, non-chelated control group within the European MDS registry, that met the eligibility criteria for starting iron chelation. A Cox proportional hazards model was used to assess overall survival, treating receipt of chelation as a time-varying variable. Additionally, chelated and non-chelated patients were compared using a propensity-score matched model. Of 2200 patients, 224 received iron chelation. The hazard ratio and 95% confidence interval for overall survival for chelated patients, adjusted for age, sex, comorbidity, performance status, cumulative red blood cell transfusions, IPSS-R, and presence of ringed sideroblasts was 0.50 (0.34-0.74). The propensity-score analysis, matched for age, sex, country, red blood cell transfusion intensity, ferritin level, comorbidity, performance status, and IPSS-R and additionally corrected for cumulative red blood cell transfusions and presence of ringed sideroblasts, demonstrated a significantly improved overall survival for chelated patients with a hazard ratio of 0.42 (0.27-0.63) compared to non-chelated patients. Up to 39% of chelated patients reached an erythroid response. In conclusion, our results suggest that iron chelation may improve overall survival and hematopoiesis in transfused lower-risk myelodysplastic syndrome patients. This trial was registered at www.clinicaltrials.gov as #NCT00600860.

4.
Haematologica ; 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171638

RESUMO

Progression-free survival of lower-risk myelodysplastic syndromes patients treated with red blood cell transfusions is usually reduced, but it is unclear whether transfusion dose density is an independent prognostic factor. The European MDS Registry collects prospective data at 6-monthly intervals of newly diagnosed lower-risk myelodysplastic syndromes patients from 16 European countries and Israel. Data on the transfusion dose density - the cumulative dose received at the end of each interval divided by the time since the beginning of the interval in which the first transfusion was received - were analyzed using proportional hazards regression with time-varying co-variates, with death and progression to higher-risk myelodysplastic syndromes /acute myeloid leukemia as events. Of the 1267 patients included in the analyses, 317 patients died without progression, in 162 patients the disease had progressed. Progression-free survival was significantly associated with age, EQ-5D index, baseline WHO classification, bone marrow blast count, cytogenetic risk category, number of cytopenias, and country. Transfusion dose density was inversely associated with progression-free survival (p<1x10-4): dose density had an increasing effect on hazard until a dose density of 3 units/16 weeks. The transfusion dose density effect continued to increase beyond 8 units/16 weeks after correction for the impact of treatment with erythropoietin agents, lenalidomide and/or iron chelators. Conclusion: the negative effect of transfusion treatment on progression-free survival already occurs at transfusion densities below 3 units/16 weeks. This indicates that transfusion dependency, even at relatively low dose densities, may be considered as an indicator of inferior progression-free survival. This trial was registered at www.clinicaltrials.gov as #NCT00600860.

5.
Cytometry B Clin Cytom ; 96(3): 215-222, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30963682

RESUMO

BACKGROUND: Compelling evidence has emerged for the relevance of flow cytometry (FC) in the diagnostic work-up of myelodysplastic syndromes (MDS) but due to technical issues, the erythroid lineage has been under investigated, specifically in the therapeutic context. METHODS: Using the "no red cell lysis" method developed to set up the RED-score, we specifically quantified the fraction of CD117/c-KIT-expressing erythroid precursors in a cohort of 144 MDS patients and studied the correlation with response to erythropoiesis-stimulating agents (ESA) in a sub cohort of 63 low-risk MDS patients. RESULTS: We confirmed the previously reported increase in CD117/c-KIT-expressing erythroid precursors in a subset of MDS patients and demonstrated a strong association between a cut off of CD117/c-KIT-expressing erythroid precursors ≥3% and ESA response (P = 0.001), independent of red blood cell requirement. From our observations, we hypothesized that a decrease in CD117/c-KIT-expressing erythroid precursors could be a mechanism of ESA failure. Moreover, the fraction of CD117/c-KIT-expressing erythroid precursors was correlated with progression-free survival in low-risk MDS patients (P = 0.018). In vitro, we demonstrated in an EPO dependent cell line that CD117/c-KIT expression is necessary for cell survival under EPO stimulation. CONCLUSIONS: The quantification of the CD117/c-KIT-expressing erythroid precursors could be proposed as a new theranostic and prognostic marker in MDS treated by ESA. Future studies will be required to determine whether modulating CD117/c-KIT expression and signaling could be used to improve anemia in MDS. © 2019 International Clinical Cytometry Society.

6.
Int J Hematol ; 110(2): 161-169, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31020568

RESUMO

Hypomethylating agents (HMAs), azacitidine and decitabine, are standards of care in higher-risk myelodysplastic syndromes and in acute myeloid leukemia patients ineligible for intensive therapy. Over the last 10 years, research efforts have sought to better understand their mechanism of action, both at the molecular and cellular level. These efforts have yet to robustly identify biomarkers for these agents. The clinical activity of HMAs in myeloid neoplasms has been firmly established now but still remains of limited magnitude. Besides optimized use at different stages of the disease, most of the expected clinical progress with HMAs will come from the development of second-generation compounds orally available and/or with improved pharmacokinetics, and from the search, so far mostly empirical, of HMA-based synergistic drug combinations.

7.
Leukemia ; 33(10): 2466-2480, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30894665

RESUMO

Islands of CD123high cells have been commonly described in the bone marrow of patients with chronic myelomonocytic leukemia (CMML). Using a multiparameter flow cytometry assay, we detected an excess of CD123+ mononucleated cells that are lineage-negative, CD45+, CD11c-, CD33-, HLA-DR+, BDCA-2+, BDCA-4+ in the bone marrow of 32/159 (20%) patients. Conventional and electron microscopy, flow cytometry detection of cell surface markers, gene expression analyses, and the ability to synthesize interferon alpha in response to Toll-like receptor agonists identified these cells as bona fide plasmacytoid dendritic cells (pDCs). Whole-exome sequencing of sorted monocytes and pDCs identified somatic mutations in genes of the oncogenic RAS pathway in the two cell types of every patient. CD34+ cells could generate high amount of pDCs in the absence of FMS-like tyrosine kinase 3-ligand (FLT3L). Finally, an excess of pDCs correlates with regulatory T cell accumulation and an increased risk of acute leukemia transformation. These results demonstrate the FLT3L-independent accumulation of clonal pDCs in the bone marrow of CMML patients with mutations affecting the RAS pathway, which is associated with a higher risk of disease progression.

8.
Curr Oncol Rep ; 21(2): 16, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30715623

RESUMO

PURPOSE OF REVIEW: The extensive genomic characterization of acute myeloid leukemia (AML) led to the identification of a vast number of potential therapeutic targets. We review relevant data that have led to recent approval of new targeted therapies in AML and discuss the most promising drugs currently in development in this disease. RECENT FINDINGS: New formulations of cytotoxic agents, namely CPX-351 and gemtuzumab ozogamicin, improve the outcome of defined subgroup of patients. Midostaurin added to intensive chemotherapy is approved in FLT3-mutated AML. More selective FLT3 inhibitors and the IDH inhibitors enasidenib and ivosidenib have shown significant single agent activity in the relapsed setting, and preliminary results of combination strategies are encouraging. The addition of the BCL2 inhibitor venetoclax appears to markedly improve the results of hypomethylating agents. The therapeutic armamentarium of AML now includes novel cytotoxic drugs, drugs targeting recurrent oncogenes, or functional vulnerabilities of leukemic cells. Further work is required to optimize their integration to the current framework of AML management, including allogeneic stem cell transplantation.

9.
Nat Commun ; 9(1): 5455, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30575719

RESUMO

Non-classical monocyte subsets may derive from classical monocyte differentiation and the proportion of each subset is tightly controlled. Deregulation of this repartition is observed in diverse human diseases, including chronic myelomonocytic leukemia (CMML) in which non-classical monocyte numbers are significantly decreased relative to healthy controls. Here, we identify a down-regulation of hsa-miR-150 through methylation of a lineage-specific promoter in CMML monocytes. Mir150 knock-out mice demonstrate a cell-autonomous defect in non-classical monocytes. Our pulldown experiments point to Ten-Eleven-Translocation-3 (TET3) mRNA as a hsa-miR-150 target in classical human monocytes. We show that Tet3 knockout mice generate an increased number of non-classical monocytes. Our results identify the miR-150/TET3 axis as being involved in the generation of non-classical monocytes.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Dioxigenases/metabolismo , Leucemia Mielomonocítica Crônica/imunologia , MicroRNAs/metabolismo , Monócitos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Metilação de DNA , Regulação para Baixo , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Células K562 , Leucemia Mielomonocítica Crônica/metabolismo , Masculino , Camundongos , Camundongos Knockout , Cultura Primária de Células , Regiões Promotoras Genéticas
12.
Br J Haematol ; 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30198568

RESUMO

The diagnosis of Waldenström Macroglobulinaemia (WM)/lymphoplasmacytic lymphoma (LPL) remains one of exclusion because other B-cell lymphoproliferative disorders (B-LPD), such as marginal zone lymphoma (MZL), can fulfil similar criteria, including MYD88 L265P mutation. It has been suggested that expression of the myeloid marker CD13 (also termed ANPEP) is more frequent in LPL than in other B-LPD and has also been described on normal and malignant plasma cells. Here, CD13 expression was tested in a cohort of 1037 B-LPD patients from 3 centres by flow cytometry. The percentage of CD13-expressing cells was found to be variable among B-LPD but significantly higher in WM/LPL (median 31% vs. 0% in non-WM/LPL, P < 0·001). In multivariate linear regression, CD13 expression remained significantly associated with a diagnosis of WM/LPL (P < 0·001). A cut-off value of 2% of CD19+ cells co-expressing CD13 yielded the best diagnostic performance for WM/LPL assertion. This was further improved by association with the presence or absence of IgM paraprotein. Finally, given that previously published transcriptomic data revealed no difference in CD13 (also termed ANPEP) mRNA between normal and pathological B-cells, the hypothesis of some post-transcriptional regulation must be favoured. These results suggest that testing for CD13 expression in routine flow cytometry panels could help to discriminate WM/LPL from other B-LPD.

13.
Blood Adv ; 2(16): 2079-2089, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30126931

RESUMO

Prognosis of lower-risk (International Prognostic Scoring System [IPSS] low/intermediate-1) myelodysplastic syndrome (MDS) is heterogeneous and relies on steady-state assessment of cytopenias. We analyzed relative drops in neutrophil and platelet counts during the first 6 months of follow-up of lower-risk MDS patients. We performed a landmark analysis of overall survival (OS) of lower-risk MDS patients prospectively included in the European LeukaemiaNet MDS registry having a visit at 6 ± 1 month from inclusion to assess the prognostic relevance of relative drops in neutrophils and platelets, defined as (count at landmark - count at inclusion)/count at inclusion. Of 2102 patients, 807 were eligible for the stringent 6-month landmark analysis. Median age was 73 years. Revised IPSS was very low, low, and intermediate/higher in 26%, 43%, and 31% of patients, respectively. A relative drop in platelets >25% at landmark predicted shorter OS (5-year OS, 21.9% vs 48.6% with platelet drop ≤25%, P < 10-4), regardless of baseline IPSS-revised or absolute platelet counts. Relative neutrophil drop >25% had no significant impact on OS. We built a classifier based on red blood cell transfusion dependence (RBC-TD) and relative platelet drop >25% at landmark. Patients with none (62%), either (27%), or both criteria (11%) had 5-year OS of 53.3%, 32.7%, and 9.0%, respectively (P < 10-4). This classifier was validated in an independent cohort of 335 patients. Combining relative platelet drop >25% and RBC-TD at 6 months from diagnosis provides an inexpensive and noninvasive way to predict outcome in lower-risk MDS. This study was registered at www.clinicaltrials.gov as #NCT00600860.

14.
Blood Adv ; 2(14): 1765-1772, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30037803

RESUMO

Most studies of immunosuppressive therapy (IST) in myelodysplastic syndromes (MDS) are limited by small numbers and their single-center nature, and report conflicting data regarding predictors for response to IST. We examined outcomes associated with IST and predictors of benefit in a large international cohort of patients with MDS. Data were collected from 15 centers in the United States and Europe. Responses, including red blood cell (RBC) transfusion independence (TI), were assessed based on the 2006 MDS International Working Group criteria, and overall survival (OS) was estimated by Kaplan-Meier methods. Logistic regression models estimated odds for response and TI, and Cox Proportional Hazard models estimated hazards ratios for OS. We identified 207 patients with MDS receiving IST, excluding steroid monotherapy. The most common IST regimen was anti-thymocyte globulin (ATG) plus prednisone (43%). Overall response rate (ORR) was 48.8%, including 11.2% (95% confidence interval [CI], 6.5%-18.4%) who achieved a complete remission and 30% (95% CI, 22.3%-39.5%) who achieved RBC TI. Median OS was 47.4 months (95% CI, 37-72.3 months) and was longer for patients who achieved a response or TI. Achievement of RBC TI was associated with a hypocellular bone marrow (cellularity < 20%); horse ATG plus cyclosporine was more effective than rabbit ATG or ATG without cyclosporine. Age, transfusion dependence, presence of paroxysmal nocturnal hemoglobinuria or large granular lymphocyte clones, and HLA DR15 positivity did not predict response to IST. IST leads to objective responses in nearly half the selected patients with the highest rate of RBC TI achieved in patients with hypocellular bone marrows.

16.
EBioMedicine ; 31: 174-181, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29728305

RESUMO

Somatic mutations contribute to the heterogeneous prognosis of chronic myelomonocytic leukemia (CMML). Hypomethylating agents (HMAs) are active in CMML, but analyses of small series failed to identify mutations predicting response or survival. We analyzed a retrospective multi-center cohort of 174 CMML patients treated with a median of 7 cycles of azacitidine (n = 68) or decitabine (n = 106). Sequencing data before treatment initiation were available for all patients, from Sanger (n = 68) or next generation (n = 106) sequencing. Overall response rate (ORR) was 52%, including complete response (CR) in 28 patients (17%). In multivariate analysis, ASXL1 mutations predicted a lower ORR (Odds Ratio [OR] = 0.85, p = 0.037), whereas TET2mut/ASXL1wt genotype predicted a higher CR rate (OR = 1.18, p = 0.011) independently of clinical parameters. With a median follow-up of 36.7 months, overall survival (OS) was 23.0 months. In multivariate analysis, RUNX1mut (Hazard Ratio [HR] = 2.00, p = .011), CBLmut (HR = 1.90, p = 0.03) genotypes and higher WBC (log10(WBC) HR = 2.30, p = .005) independently predicted worse OS while the TET2mut/ASXL1wt predicted better OS (HR = 0.60, p = 0.05). CMML-specific scores CPSS and GFM had limited predictive power. Our results stress the need for robust biomarkers of HMA activity in CMML and for novel treatment strategies in patients with myeloproliferative features and RUNX1 mutations.


Assuntos
Azacitidina/análogos & derivados , Azacitidina/administração & dosagem , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA , Leucemia Mielogênica Crônica BCR-ABL Positiva , Mutação , Proteínas Proto-Oncogênicas , Proteínas Repressoras , Idoso , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Decitabina , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
18.
Biol Blood Marrow Transplant ; 24(8): 1754-1758, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29649620

RESUMO

Patients with primary refractory or relapsed acute myeloid leukemia (RR-AML) have very poor prognosis. Due to limited treatment options, some patients are treated with hypomethylating agents (HMAs) due to their tolerability. Little is known about the role of allogeneic hematopoietic stem cell transplantation (HSCT) following HMA therapy in this setting. We retrospectively analyzed an international cohort of 655 RR-AML patients who received HMA therapy to study patterns and outcomes with HSCT. Only 37 patients (5.6%) patients underwent HSCT after HMA therapy. The conditioning regimen was myeloablative in 57% and nonmyeloablative in 43%. Patients received matched unrelated donor, matched sibling, haploidentical and mismatched unrelated HSCT in 56%, 24%, 16% and 4% of cases, respectively. Acute GvHD and chronic GvHD were observed in 40% and 17% of patients. While the median OS for the entire cohort of patients was 15.3 months (95% CI 9.5 - 21.7 months), OS reached 29.7 months (95% CI 7.01 - not-reached) for patients who achieved a complete remission (CR) to HMA and no intervening therapies between HMA therapy and HSCT. Our study suggests that HMA therapy can effectively bridge some patients with RR-AML to HSCT.

19.
Blood Adv ; 2(8): 923-932, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29685952

RESUMO

Although hypomethylating agents (HMAs) are frequently used in the frontline treatment of older acute myeloid leukemia (AML) patients, little is known about their effectiveness in relapsed or primary treatment-refractory (RR)-AML. Using an international multicenter retrospective database, we studied the effectiveness of HMAs in RR-AML and evaluated for predictors of response and overall survival (OS). A total of 655 patients from 12 centers received azacitidine (57%) or decitabine (43%), including 290 refractory (44%) and 365 relapsed (56%) patients. Median age at diagnosis was 65 years. Best response to HMAs was complete remission (CR; 11%) or CR with incomplete count recovery (CRi; 5.3%). Additionally, 8.5% experienced hematologic improvement. Median OS was 6.7 months (95% confidence interval, 6.1-7.3). As expected, OS differed significantly by best response, with patients achieving CR and CRi having a median OS of 25.3 and 14.6 months, respectively. In multivariate analysis, the presence of ≤5% circulating blasts and a 10-day schedule of decitabine were associated with improved response rates, whereas the presence of >5% circulating blasts and >20% bone marrow blasts were associated with decreased OS. A significant subset of RR-AML patients (16%) achieved CR/CRi with HMAs and experienced a median OS of 21 months. Outside of a clinical trial, HMAs represent a reasonable therapeutic option for some patients with RR-AML.

20.
Blood ; 132(2): 187-196, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-29692343

RESUMO

Mutations in receptor tyrosine kinase/RAS signaling pathway genes are frequent in core-binding factor (CBF) acute myeloid leukemias (AMLs), but their prognostic relevance is debated. A subset of CBF AML patients harbors several signaling gene mutations. Genotyping of colonies and of relapse samples indicates that these arise in independent clones, thus defining a process of clonal interference (or parallel evolution). Clonal interference is pervasive in cancers, but the mechanisms underlying this process remain unclear, and its prognostic impact remains unknown. We analyzed a cohort of 445 adult and pediatric patients with CBF AML treated with intensive chemotherapy and with deep sequencing of 6 signaling genes (KIT, NRAS, KRAS, FLT3, JAK2, CBL). A total of 152 (34%), 167 (38%), and 126 (28%) patients harbored no, a single, and multiple signaling clones (clonal interference), respectively. Clonal interference of signaling mutations was associated with older age (P = .004) and inv(16) subtype (P = .025) but not with white blood cell count or mutations in chromatin or cohesin genes. The median allele frequency of signaling mutations was 31% in patients with a single clone or clonal interference (P = .14). The repertoire of KIT, FLT3, and NRAS/KRAS variants differed between groups. Clonal interference did not affect complete remission rate or minimal residual disease after 1-2 courses, but it did convey inferior event-free survival (P < 10-4), whereas the presence of a single signaling clone did not (P = .44). This inferior outcome was independent of clinical parameters and of the presence of specific signaling clones. Our results suggest that specific clonal architectures can herald distinct prognoses in AML.

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