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Background Aims: Myelodysplastic syndromes (MDS) are a group of clonal stem cell disorders affecting the normal hematopoietic differentiation process and leading to abnormal maturation and differentiation of all blood cell lineages. Treatment options are limited, and there is an unmet medical need for effective therapies for patients with severe cytopenias., Methods: We demonstrate that multipotent adult progenitor cells (MAPC) improve the function of hematopoietic progenitors derived from human MDS bone marrow (BM) by significantly increasing the frequency of primitive progenitors as well as the number of myeloid colonies., Results: This effect was more pronounced in a non-contact culture, indicating the importance of soluble factors produced by the MAPC cells. Moreover, the cells did not stimulate the growth of the abnormal MDS clone, as shown by fluorescent in situ hybridization analysis on BM cells from patients with a known genetic abnormality. We also demonstrate that MAPC cells can provide stromal support for patient-derived hematopoietic cells. When MAPC cells were intravenously injected into a mouse model of MDS, they migrated to the site of injury and increased the hematopoietic function in diseased mice., Discussion: The preclinical studies undertaken here indicate an initial proof of concept for the use of MAPC cell therapy in patients with MDS-related severe and symptomatic cytopenias and should pave the way for further investigation in clinical trials., (Copyright © 2017. Published by Elsevier Inc.)

High-risk myelodysplastic syndrome (MDS) patients have usually a less favorable outcome after intensive treatment compared with de novo acute myeloid leukemia (AML) patients. This may reflect different disease-related and patient-related factors. The purpose of this analysis is to identify disease-specific prognostic factors and to develop prognostic scores for both patient groups. A total of 692 patients in the EORTC/GIMEMA AML-10 study and 289 patients in the CRIANT study received identical remission-induction and consolidation treatment. Estimated 5-year survival rate was 34 % in the AML-10 versus 27 % in the CRIANT study, and estimated disease-free survival was 40 % versus 28 %, respectively. In multivariate analysis, cytogenetic characteristics, white blood count, and age appeared prognostic for survival in both studies. French-American-British (FAB) subtype and performance status were prognostic in the AML-10 study only, whereas number of cytopenias and duration of antecedent hematologic disorder >6 months were prognostic in the CRIANT study only. The prognostic scores distinguish three groups with a 5-year survival rate of 54, 38, and 19 % in the AML-10 study versus 69, 37, and 5 % in the CRIANT study. The prognostic value of these scores has been validated on two external series. The new scoring systems form a practical tool to predict the outcome of individual MDS and AML patients treated with intensive antileukemic therapy.

Background: Most patients with myelodysplastic syndromes (MDS) require transfusions at the risk of iron overload and associated organ damage, and death. Emerging evidence indicates that iron chelation therapy (ICT) could reduce mortality and improve survival in transfusion-dependent MDS patients, especially those classified as International Prognostic Scoring System (IPSS) Low or Intermediate-1 (Low/Int-1)., Methods: Follow-up of a retrospective study. Sample included 127 Low/Int-1 MDS patients from 28 centers in Belgium. Statistical analysis stratified by duration (≥6 versus <6 months) and quality of chelation (adequate versus weak)., Results: Crude chelation rate was 63% but 88% among patients with serum ferritin ≥1000 μg/L. Of the 80 chelated patients, 70% were chelated adequately mainly with deferasirox (26%) or deferasirox following deferoxamine (39%). Mortality was 70% among non-chelated, 40% among chelated, 32% among patients chelated ≥6 m, and 30% among patients chelated adequately; with a trend toward reduced cardiac mortality in chelated patients. Overall, median overall survival (OS) was 10.2 years for chelated and 3.1 years for non-chelated patients (p<0.001). For patients chelated ≥6 m or patients classified as adequately chelated, median OS was 10.5 years. Mortality increased as a function of average monthly transfusion intensity (HR=1.08, p=0.04) but was lower in patients receiving adequate chelation or chelation ≥6 m (HR=0.24, p<0.001)., Conclusion: Six or more months of adequate ICT is associated with markedly better overall survival. This suggests a possible survival benefit of ICT in transfusion-dependent patients with lower-risk MDS., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Tumor-necrosis factor alpha activity has been correlated to ineffective erythropoiesis in lower risk myelodysplastic syndromes. Infliximab (Remicade(®)) is an anti-tumor necrosis factor alpha chimeric antibody that is used in the treatment of patients with rheumatoid arthritis or Crohn's disease. Forty-six patients with myelodysplastic syndromes and a relatively low risk of developing acute leukemia were included in a randomized phase II study assessing the therapeutic activity of two dosages of infliximab administration (3 mg/kg vs. 5 mg/kg). The primary end point was the response rate. Responses were observed in 3 of 22 patients (13.1%) randomized to the 3 mg/kg arm, versus 0 of 21 patients randomized in the 5 mg/kg arm. According to the statistical design of the current study, neither of the two infliximab dose schedules tested showed sufficient activity as a single agent in this cohort of unselected patients with early myelodysplastic syndrome.

Transfusion dependency and iron overload are common among patients with myelodysplastic syndromes (MDS) treated with red blood cell (RBC) transfusions. Transfusion dependency is associated with leukemic progression and shorter survival. Guidelines recommend iron chelation therapy to manage iron overload, however little is known about the chelation patterns in daily clinical practice. The objective of this multicenter, retrospective, cross-sectional, observational study was to evaluate iron status and its management in transfusion-dependent MDS patients. A total of 193 patient records from 29 centers were eligible for inclusion. Median patient age was 76, and median age at diagnosis of MDS was 74. Patients had received an average of 13.4 ± 7.6 RBC units in the past 4 months; 44% had received more than 50 units since their MDS diagnosis. Medium serum ferritin was 1,550 μg/L. Ninety patients (46.6%) received iron chelation therapy with either deferoxamine (41%), deferasirox (36%), and deferoxamine followed by deferasirox (23%). There were no statistically significant differences between chelated and nonchelated patients in terms of International Prognostic Scoring System (IPSS), French-American-British (FAB), and/or World Health Organization (WHO) status, though chelated patients had received more RBC transfusions (p = 0.014). Iron chelation therapy may be underutilized in transfusion-dependent patients. Undertreatment can be reduced by complementing sound clinical judgment with the generally accepted guidelines of a serum ferritin level >1,000 μg/L and/or two or more RBC transfusions per month for the past year; considering patients on the basis of their IPSS, FAB, and/or WHO status; and individually tailored treatment regimens. Prospective randomized trials are necessary to establish causally the efficacy of iron chelation therapy in MDS.

Background: Allogeneic stem cell transplantation is usually considered the only curative treatment option for patients with advanced or transformed myelodysplastic syndromes in complete remission, but post-remission chemotherapy and autologous stem cell transplantation are potential alternatives, especially in patients over 45 years old., Design and Methods: We evaluated, after intensive anti-leukemic remission-induction chemotherapy, the impact of the availability of an HLA-identical sibling donor on an intention-to treat basis. Additionally, all patients without a sibling donor in complete remission after the first consolidation course were randomized to either autologous peripheral blood stem cell transplantation or a second consolidation course consisting of high-dose cytarabine., Results: The 4-year survival of the 341 evaluable patients was 28%. After achieving complete remission, the 4-year survival rates of patients under 55 years old with or without a donor were 54% and 41%, respectively, with an adjusted hazard ratio of 0.81 (95% confidence interval [95% CI], 0.49-1.35) for survival and of 0.67 (95% CI, 0.42-1.06) for disease-free survival. In patients with intermediate/high risk cytogenetic abnormalities the hazard ratio in multivariate analysis was 0.58 (99% CI, 0.22-1.50) (P=0.14) for survival and 0.46 (99% CI, 0.22-1.50) for disease-free survival (P=0.03). In contrast, in patients with low risk cytogenetic characteristics the hazard ratio for survival was 1.17 (99% CI, 0.40-3.42) and that for disease-free survival was 1.02 (99% CI, 0.40-2.56). The 4-year survival of the 65 patients randomized to autologous peripheral blood stem cell transplantation or a second consolidation course of high-dose cytarabine was 37% and 27%, respectively. The hazard ratio in multivariate analysis was 1.22 (95% CI, 0.65-2.27) for survival and 1.02 (95% CI, 0.56-1.85) for disease-free survival., Conclusions: Patients with a donor and candidates for allogeneic stem cell transplantation in first complete remission may have a better disease-free survival than those without a donor in case of myelodysplastic syndromes with intermediate/high-risk cytogenetics. Autologous peripheral blood stem cell transplantation does not provide longer survival than intensive chemotherapy.

We studied the immune compartment in patients with myelodysplastic syndromes. We show increased surface expression of activation markers (HLA-DR(+), CD57(+), CD28(-), CD62L(-)) on T lymphocytes in blood and bone marrow (n=131). T cell activation was not restricted to any relevant clinical subgroup (FAB, IPSS, cytogenetics) and did not correlate with blood counts or need for treatment. In vitro clonogenic growth of marrow mononuclear cells (n=18) was not influenced by T cells expressing these markers. In addition, using X-chromosome inactivation analysis (n=12) we demonstrate clonal involvement of NK and B cells in half of these patients. We conclude that although activated T lymphocytes can be found in MDS, their role in disease pathogenesis remains unclear in the majority of patients.

Background and Objectives: Intensive chemotherapy followed by autologous hematopoietic stem cell transplantation (HSCT) is a curative treatment option for patients with myelodysplastic syndromes (MDS). Peripheral blood (PB) HSCT was introduced in 1992 and PB has become the source of choice of autologous stem cells worldwide. Autologous PB stem cells result in faster hematopoietic recovery, but may be associated with a higher risk of relapse., Design and Methods: We analyzed the data of 336 patients transplanted after 1992 with either bone marrow (BM) (n=104) or PB (n=232)., Results: Various factors had an impact on event-free survival in univariate analysis: age hazard ratio [HR]=1.1 per 10 years; p=0.12), source of stem cells (HR=1.2, p=0.22), interval between diagnosis and transplantation (HR=1.0 per month; p=0.87), and therapy-related vs primary disease (HR=0.5; p=0.002). In the multivariate Cox model, the event-free survival was not different after PB or BM HSCT with a HR of 0.93 (95% confidence interval of 0.67 - 1.30; p=0.67). The relapse risk after transplantation with stem cells from either source was similar with a HR of 1.1. A significant interaction (p=0.02) between age and the source of stem cells indicated a more favorable potential of autologous PB HSCT in young age groups., Interpretation and Conclusions: Autologous PB and BM HSCT result in equivalent outcomes. Therefore, given the more rapid hematopoietic recovery PB is the preferred source of stem cells.

Fludarabine in addition to cytosine-arabinoside (ARA-C) increases the accumulation of ARA-C-5'-triphosphate (ARA-CTP), which is responsible for the cytotoxic effect in leukemic blasts. In a randomized phase 3 trial, patients with high-risk myelodysplastic syndrome (MDS) (n = 91) or elderly patients with acute myeloid leukemia (AML) (n = 43) were randomized to receive 2 induction courses consisting of ARA-C (2 g/m2 days 1 through 5) and granulocyte colony-stimulating factor (G-CSF) (filgrastim, 5 microg/kg) during and after chemotherapy with or without fludarabine (25 mg/m2, days 1 through 5) (FLAG versus AG). Consolidation consisted of daunorubicin (45 mg/m2, days 1 through 3) and ARA-C (200 mg/m2, days 1 through 7). Complete remission (CR) rate following AG was 65% versus 71% with FLAG (P =.49). Overall survival (OS) at 24 months was 24% for AG treatment and 39% for FLAG (P =.32). Event-free survival (EFS) at 2 years was 10% and 19% (P =.31) for the AG and FLAG treatments, respectively. Platelet and granulocyte recovery times after the second cycle were prolonged in the FLAG treatment group. Grades 3 to 4 neurotoxicities were more often reported in the FLAG arm (14% versus 3%, P =.03), whereas no significant differences in other toxicities were observed. In a cohort of patients, the in vivo accumulation of ARA-CTP in leukemic cells was determined. Although ARA-CTP accumulation in leukemic cells after FLAG was enhanced, clinical outcome in terms of CR rate, OS, EFS, and disease-free survival (DFS) was not significantly improved by combining fludarabine with ARA-C.

Amifostine is a phosphorylated aminothiol that has besides anti-oxidative and cytoprotective properties, also survival- and growth-promoting effects on hematopoietic progenitor cells. Clinical studies have demonstrated that infusions with amifostine are able to increase erythro-, myelo-, and thrombopoiesis in some patients with myelodysplastic syndromes (MDS). Since clonal and non-clonal progenitors can coexist in early phase MDS, we have studied if amifostine exerts a selective growth-promoting effect on clonal or non-clonal cells. For this purpose, purified CD34(+) marrow progenitors from nine female MDS patients were grown in short- and long-term cultures. Clonality was studied on individual colonies using polymorphisms in the human androgen receptor assay (HUMARA) locus. Three patients had growth of residual non-clonal progenitors at baseline. Continuous exposure to 100nM amifostine exerted a growth-promoting effect on progenitors in 50% of the patients. HUMARA patterns of individual colony-forming unit granulocyte macrophage (CFU-GM; 5/9) and 5 week long-term culture-initiating cells (LTC-IC; 2/9) were compared without and with amifostine exposure. We did not observe preferential stimulation of clonal or non-clonal progenitors. Based on these results, the stimulation of committed and immature progenitor growth in MDS by amifostine, is non-selective and does not favor nor suppress the growth of residual non-clonal cells.

Myelodysplastic syndromes (MDS) are clonal disorders of an immature hematopoietic progenitor cell. MDS hematopoiesis is characterized by abnormal progenitor proliferation and impaired cellular differentiation and maturation. As a consequence, the majority of MDS patients have a gradual evolution towards progressive bone marrow failure and/or leukemic transformation. The efforts made by several research groups during the last few years have helped to unravel the complex underlying pathogenesis of MDS. In this review, we will focus on the principal cytogenetic and molecular abnormalities involved in MDS initiation and disease progression. Additionally, we will discuss the influence of the marrow microenvironment on survival and proliferation of hematopoietic progenitors in MDS.

The clonality of mature peripheral blood-derived myeloid and lymphoid cells and bone marrow haemopoietic progenitors from 18 females with myelodysplasia (MDS) (five refractory anaemia, RA; one RA with ringed sideroblasts, RARS; three chronic myelomonocytic leukaemia, CMML; four RA with excess of blasts, RAEB; five RAEB in transformation, RAEB-t) was studied by X-chromosome inactivation analysis. Using the human androgen-receptor (HUMARA) assay, we analysed the clonal patterns of highly purified immature CD34+38- and committed CD34+38+ marrow-derived progenitors, and CD16+14- granulocytes, CD14+ monocytes, CD3+ T and CD19+ B lymphocytes from peripheral blood. In high-risk patients (RAEB, RAEB-t), clonality analysis was performed before and after intensive remission-induction treatment. All patients, except one with RA, had predominance of a single clone in their granulocytes and monocytes. The same clonal pattern was found in CD34+ progenitor cells. In contrast, CD3+ T lymphocytes were polyclonal or oligoclonal in 14/18 patients. X-chromosome inactivation patterns of CD19+ B cells were highly concordant with CD3+ T cells except for two patients (one RA, one CMML) with monoclonal B and polyclonal T lymphocytes, therefore suggesting a clonal mutation in a progenitor common to the myeloid and B-lymphoid lineages or the coexistence of MDS and a B-cell disorder in these particular patients. After high-dose non-myeloablative chemotherapy, polyclonal haemopoiesis was reinstalled in the mature myeloid cells and immature and committed marrow progenitors in three of four patients achieving complete haematological remission. Therefore we conclude that most haematological remissions in MDS are associated with restoration of polyclonal haemopoiesis. [ABSTRACT FROM AUTHOR]

Abstract: Dendritic cells (DC) are pivotal for T cell-mediated immunity. We investigated the early and terminal maturation of monocyte-derived DC (MoDC) in myelodysplastic syndromes (FAB subtypes refractory anemia (MDS-RA) or refractory anemia with ringed sideroblasts (MDS-RARS)). Immature MoDC were obtained by culture of monocytes with GM-CSF and IL-4 for 8 days. To obtain mature MoDC, TNF-α was added during the final three culture days. T cell proliferation and T cell cytokine secretion in mixed lymphocyte reactions (MLR) unveiled a strong reduction of allostimulatory capacity of mature but also of immature MoDC from MDS patients. Immature MoDC from MDS patients exhibited an almost normal immunophenotype, but secreted substantially less IL-12 and more IL-10 in response to LPS/IFN-γ than normal controls. Terminal addition of TNF-α to GM-CSF/IL-4 treated monocytes failed to extinguish cytokine production by MDS MoDC and failed to induce the expected membrane upregulation of costimulatory and other ligands as in normal controls. While our data provide further support for previous studies that have indicated an impaired differentiation of immature towards mature MoDC, they also clearly demonstrate a qualitatively and quantitatively altered cytokine secretion at the level of immature MoDC, which may in part explain the reduced allostimulatory capacity of these cells. These alterations may contribute to immune modulation of the clinical phenotype of marrow failure in MDS, and may have to be considered when designing DC-based immunotherapeutic strategies for MDS. [Copyright &y& Elsevier]