Genome-wide profiling of methylation identifies novel targets with aberrant hyper-methylation and reduced expression in low-risk myelodysplastic syndromes

Gene expression profiling signatures may be used to classify the subtypes of Myelodysplastic syndrome (MDS) patients. However, there are few reports on the global methylation status in MDS. The integration of genome-wide epigenetic regulatory marks with gene expression levels would provide additional information regarding the biological differences between MDS and healthy controls. Gene expression and methylation status were measured using high-density microarrays. A total of 552 differentially methylated CpG loci were identified as being present in low-risk MDS; hypermethylated genes were more frequent than hypomethylated genes. In addition, mRNA expression profiling identified 1005 genes that significantly differed between low-risk MDS and the control group. Integrative analysis of the epigenetic and expression profiles revealed that 66.7% of the hypermethylated genes were underexpressed in low-risk MDS cases. Gene network analysis revealed molecular mechanisms associated with the low-risk MDS group, including altered apoptosis pathways. The two key apoptotic genes BCL2 and ETS1 were identified as silenced genes. In addition, the immune response and micro RNA biogenesis were affected by the hypermethylation and underexpression of IL27RA and DICER1. Our integrative analysis revealed that aberrant epigenetic regulation is a hallmark of low-risk MDS patients and could have a central role in these diseases. © 2013 Macmillan Publishers Limited All rights reserved

Eltrombopag increases the hematopoietic supporting ability of mesenchymal stem/stromal cells

[Background]: Eltrombopag (EP) is a small molecule that acts directly on hematopoietic stem cells (HSCs) and megakaryocytes to stimulate the hematopoietic process. Mesenchymal stem/stromal cells (MSCs) are key hematopoietic niche regulators. [Objectives]: We aimed to determine whether EP has any effect on MSC function and properties (especially on their hematopoietic-supporting ability) and if so, what changes (e.g. genome-wide transcriptomic alterations) are induced in MSC after EP treatment. [Design/Methods]: MSCs were isolated from 12 healthy donors and treated with 15 µM and 50 µM of EP for 24 h. The toxicity of the drug on MSCs and their differentiation ability were analyzed, as well as the transcriptomic profile, reactive oxygen species (ROS) and DNA damage and the changes induced in the clonogenic capacity of HSCs.[Results]: The results show that EP also modifies MSC functions, decreasing their adipogenic differentiation, increasing the expression of genes involved in hypoxia and other pathways related to oxygen homeostasis, and enhancing their ability to support hematopoiesis in vitro.[Conclusion]: Our findings support the use of EP in cases where hematopoiesis is defective, despite its well-known direct effects on hematopoietic cells. Our findings suggest that further studies on the effects of EP on MSCs from patients with aplastic anemia are warranted.This study was supported by research funding from Novartis Pharmaceuticals to FS-G. SP is supported by Fundación Española de Hematología y Hemoterapia (FEHH). SM is supported by RETIC and RICORS programs of ISCIII European Regional Development Fund (RD16/0011/0015, RD21/0017/0006), ‘A way to make Europe’ and NextGenerationEU. GJMC and ESL are supported by the Spanish Ministerio de Ciencia e Innovación (FPU18/03533 and PFIS/19/00272 respectively).Peer reviewe

Two novel variants of the ABCG5 gene cause xanthelasmas and macrothrombocytopenia: a brief review of hematologic abnormalities of sitosterolemia

[EN] Background: Sitosterolemia (STSL) is a recessive inherited disorder caused by pathogenic variants in the ABCG5 and ABCG8 genes. Increased levels of plasma plant sterols (PSs) usually result in xanthomas and premature coronary atherosclerosis, although hematologic abnormalities may occasionally be present. This clinical picture is unfamiliar to many physicians, and patients may be at high risk of misdiagnosis. Objectives: To report two novel ABCG5 variants causing STSL in a Spanish patient, and review the clinical and mutational landscape of STSL. Patient/Methods: A 46-year-old female was referred to us with lifelong macrothrombocytopenia. She showed familial hypercholesterolemia-related xanthomas. Molecular analysis was performed with high-throughput sequencing. Plasma PS levels were evaluated with gas–liquid chromatography. The STSL landscape was reviewed with respect to specific online databases and all reports published since 1974. Results: A blood smear revealed giant platelets and stomatocytes. Novel compound heterozygous variants were detected in exons 7 (c.914C>G) and 13 (c.1890delT) of ABCG5. The patient showed an increased plasma level of sitosterol. These findings support the diagnosis of STSL. In our review, we identified only 25 unrelated STLS patients who presented with hematologic abnormalities including macrothrombocytopenia

Risk factors for thrombotic microangiopathy in allogeneic hematopoietic stem cell recipients receiving GVHD prophylaxis with tacrolimus plus MTX or sirolimus

Post-transplant complications.-- et al.Transplantation-associated thrombotic microangiopathy (TA-TMA) is a feared complication of allogeneic hematopoietic SCT (HSCT) owing to its high mortality rate. The use of calcineurin inhibitors or sirolimus (SIR) for GVHD prophylaxis has been suggested as a potential risk factor. However, the impact of tacrolimus (TAC) and SIR combinations on the increased risk of TA-TMA is currently not well defined. We retrospectively analyzed the incidence of TA-TMA in 102 allogeneic HSCT recipients who consecutively received TAC plus SIR (TAC/SIR) (n=68) or plus MTX (TAC/MTX)±ATG (n=34) for GVHD prophylaxis. No significant differences were observed in the incidence of TA-TMA between patients receiving TAC/SIR vs TAC/MTX±ATG (7.4% vs 8.8%, P=0.8). Only grade III-IV acute GVHD, previous HSCT and serum levels of TAC >25 ng/mL were associated with a greater risk of TA-TMA. Patients developing TA-TMA have significantly poorer survival (P<0.001); however, TA-TMA ceased to be an independent prognostic factor when it was included in a multivariate model. In conclusion, the combination of TAC/SIR does not appear to pose a higher risk of TA-TMA. By contrast, we identified three different risk groups for developing TA-TMA.Peer Reviewe

Co-occurrence of cohesin complex and Ras signaling mutations during progression from myelodysplastic syndromes to secondary acute myeloid leukemia

Myelodysplastic syndromes (MDS) are hematological disorders at high risk of progression to secondary acute myeloid leukemia (sAML). However, the mutational dynamics and clonal evolution underlying disease progression are poorly understood at present. To elucidate the mutational dynamics of pathways and genes occurring during the evolution to sAML, next generation sequencing was performed on 84 serially paired samples of MDS patients who developed sAML (discovery cohort) and 14 paired samples from MDS patients who did not progress to sAML during follow-up (control cohort). Results were validated in an independent series of 388 MDS patients (validation cohort). We used an integrative analysis to identify how mutations, alone or in combination, contribute to leukemic transformation. The study showed that MDS progression to sAML is characterized by greater genomic instability and the presence of several types of mutational dynamics, highlighting increasing (STAG2) and newly-acquired (NRAS and FLT3) mutations. Moreover, we observed cooperation between genes involved in the cohesin and Ras pathways in 15-20% of MDS patients who evolved to sAML, as well as a high proportion of newly acquired or increasing mutations in the chromatin-modifier genes in MDS patients receiving a disease-modifying therapy before their progression to sAML.This work was supported by grants from the Spanish Fondo de Investigaciones Sanitarias FIS PI18/01500, PI17/01741, Instituto de Salud Carlos III (ISCIII), Fondo de Investigación Sanitaria (Instituto de Salud Carlos III – Contratos Río Hortega (CM17/0017), European Regional Development Fund (ERDF), Una manera de hacer Europa, European Union Seventh Framework Programme [FP7/2007-2013] under Grant Agreement nº306242-NGS-PTL, SYNtherapy: Synthetic Lethality for Personalized Therapy-based Stratification in Acute Leukemia (ERAPERMED2018-275); ISCIII (AC18/00093), Proyectos de Investigación del SACYL, Gerencia Regional de Salud de Castilla y León: GRS1850/A18, GRS1653/A17, and Centro de Investigación Biomédica en Red de Cáncer (CIBERONC CB16/12/00233). MMI is supported by a predoctoral grant from the Junta de Castilla y León, and by the Fondo Social Europeo (JCYL-EDU/556/2019 PhD scholarship) and JMHS is supported by a research grant from Fundación Española de Hematología y Hemoterapia

Clinical, biological, and prognostic implications of SF3B1 co-occurrence mutations in very low/low- and intermediate-risk MDS patients

SF3B1 is a highly mutated gene in myelodysplastic syndrome (MDS) patients, related to a specific subtype and parameters of good prognosis in MDS without excess blasts. More than 40% of MDS patients carry at least two myeloid-related gene mutations but little is known about the impact of concurrent mutations on the outcome of MDS patients. In applying next-generation sequencing (NGS) with a 117 myeloid gene custom panel, we analyzed the co-occurrence of SF3B1 with other mutations to reveal their clinical, biological, and prognostic implications in very low/low- and intermediate-risk MDS patients. Mutations in addition to those of SF3B1 were present in 80.4% of patients (median of 2 additional mutations/patient, range 0–5). The most frequently mutated genes were as follows: TET2 (39.2%), DNMT3A (25.5%), SRSF2 (10.8%), CDH23 (5.9%), and ASXL1, CUX1, and KMT2D (4.9% each). The presence of at least two mutations concomitant with that of SF3B1 had an adverse impact on survival compared with those with the SF3B1 mutation and fewer than two additional mutations (median of 54 vs. 87 months, respectively: p = 0.007). The co-occurrence of SF3B1 mutations with specific genes is also linked to a dismal prognosis: SRSF2 mutations were associated with shorter overall survival (OS) than SRSF2wt (median, 27 vs. 75 months, respectively; p = 0.001), concomitant IDH2 mutations (median OS, 11 [mut] vs. 75 [wt] months; p = 0.001), BCOR mutations (median OS, 11 [mut] vs. 71 [wt] months; p = 0.036), and NUP98 and STAG2 mutations (median OS, 27 and 11 vs. 71 months, respectively; p = 0.008 and p = 0.002). Mutations in CHIP genes (TET2, DNMT3A) did not significantly affect the clinical features or outcome. Our results suggest that a more comprehensive NGS study in low-risk MDS SF3B1mut patients is essential for a better prognostic evaluation.This work was supported by grants from the following: Contrato Rio Hortega, CM17/00171; Gerencia Regional de Salud (Castilla y León) para proyectos de investigación año 2018, 1850/A/18; Spanish Fondo de Investigaciones Sanitarias, PI15/01471, PI18/01500; Instituto de Salud Carlos III (ISCIII); European Regional Development Fund (ERDF) “Una manera de hacer Europa”; Consejería de Educación, Junta de Castilla y León (SA271P18); Proyectos de Investigación del SACYL, Spain, GRS1847/A/18, GRS1653/A17; SYNtherapy, Synthetic Lethality for Personalized Therapy-based Stratification In Acute Leukemia (ERAPERMED2018–275); ISCIII (AC18/00093), co-funded by ERDF/ESF, “Investing in your future”, by grants from Red Temática de Investigación Cooperativa en Cáncer (RTICC) (RD12/0036/0069) and Centro de Investigación Biomédica en Red de Cáncer (CIBERONC CB16/12/00233). JMHS is supported by a research grant from Fundación Española de Hematología y Hemoterapia. MM is currently supported by an Ayuda predoctoral de la Junta de Castilla y León from the Fondo Social Europeo (JCYL- EDU/556/2019 PhD scholarship)

Next generation flow for minimally-invasive blood characterization of MGUS and multiple myeloma at diagnosis based on circulating tumor plasma cells (CTPC)

Here, we investigated for the first time the frequency and number of circulating tumor plasma cells (CTPC) in peripheral blood (PB) of newly diagnosed patients with localized and systemic plasma cell neoplasms (PCN) using next-generation flow cytometry (NGF) and correlated our findings with the distinct diagnostic and prognostic categories of the disease. Overall, 508 samples from 264 newly diagnosed PCN patients, were studied. CTPC were detected in PB of all active multiple myeloma (MM; 100%), and smoldering MM (SMM) patients (100%), and in more than half (59%) monoclonal gammopathy of undetermined significance (MGUS) cases (p < 0.0001); in contrast, CTPC were present in a small fraction of solitary plasmacytoma patients (18%). Higher numbers of CTPC in PB were associated with higher levels of BM infiltration and more adverse prognostic features, together with shorter time to progression from MGUS to MM (p < 0.0001) and a shorter survival in MM patients with active disease requiring treatment (p <= 0.03). In summary, the presence of CTPC in PB as assessed by NGF at diagnosis, emerges as a hallmark of disseminated PCN, higher numbers of PB CTPC being strongly associated with a malignant disease behavior and a poorer outcome of both MGUS and MM

Ex vivo identification and characterization of a population of CD13high CD105+ CD45- mesenchymal stem cells in human bone marrow

Introduction: Mesenchymal stem cells (MSCs) are multipotent cells capable of self-renewal and multilineage differentiation. Their multipotential capacity and immunomodulatory properties have led to an increasing interest in their biological properties and therapeutic applications. Currently, the definition of MSCs relies on a combination of phenotypic, morphological and functional characteristics which are typically evaluated upon in vitro expansion, a process that may ultimately lead to modulation of the immunophenotypic, functional and/or genetic features of these cells. Therefore, at present there is great interest in providing markers and phenotypes for direct in vivo and ex vivo identification and isolation of MSCs. Methods: Multiparameter flow cytometry immunophenotypic studies were performed on 65 bone marrow (BM) samples for characterization of CD13high CD105+ CD45- cells. Isolation and expansion of these cells was performed in a subset of samples in parallel to the expansion of MSCs from mononuclear cells following currently established procedures. The protein expre

Next generation flow for minimally-invasive blood characterization of MGUS and multiple myeloma at diagnosis based on circulating tumor plasma cells (CTPC)

© The Author(s) 2018.Here, we investigated for the first time the frequency and number of circulating tumor plasma cells (CTPC) in peripheral blood (PB) of newly diagnosed patients with localized and systemic plasma cell neoplasms (PCN) using next-generation flow cytometry (NGF) and correlated our findings with the distinct diagnostic and prognostic categories of the disease. Overall, 508 samples from 264 newly diagnosed PCN patients, were studied. CTPC were detected in PB of all active multiple myeloma (MM; 100%), and smoldering MM (SMM) patients (100%), and in more than half (59%) monoclonal gammopathy of undetermined significance (MGUS) cases (p <0.0001); in contrast, CTPC were present in a small fraction of solitary plasmacytoma patients (18%). Higher numbers of CTPC in PB were associated with higher levels of BM infiltration and more adverse prognostic features, together with shorter time to progression from MGUS to MM (p <0.0001) and a shorter survival in MM patients with active disease requiring treatment (p ≤ 0.03). In summary, the presence of CTPC in PB as assessed by NGF at diagnosis, emerges as a hallmark of disseminated PCN, higher numbers of PB CTPC being strongly associated with a malignant disease behavior and a poorer outcome of both MGUS and MM.This work has been supported by the International Myeloma Foundation-Black Swan Research Initiative and the EuroFlow Consortium; Centro de Investigación Biomédica en Red de Cáncer (CIBER-ONC; Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and FONDOS FEDER), numbers: CB16/12/00400, CB16/12/00369, CB16/12/00489 and CB16/12/00233; grant SA079U14 from the Consejería de Educación, Junta de Castilla y León, Valladolid, Spain and; grant DTS15/00119 from Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain. Acuerdo de colaboración con Fundación de Hemoterapia y Hemodonación de Castilla y León, Valladolid, Spain. This study was also supported by the Qatar National Research Fund (QNRF) Award No. 7-916-3-237, the AACR-Millennium Fellowship in Multiple Myeloma Research (15-40-38-PAIV), ERA-NET TRANSCAN-2 (iMMunocell), by a 2017 Leonardo Grant (BZG10931) for Researchers and Cultural Creators, BBVA Foundation, and the European Research Council (ERC) 2015 Starting Grant (MYELOMANEXT)

Distinct mutational pattern of myelodysplastic syndromes with and without 5q– treated with lenalidomide

Financial support: This work was supported in part by a grant from the Instituto de Salud Carlos III, Ministerio de Economia y Competividad, Spain (PI/14/00013; PI/17/0575); 2017 SGR288 (GRC) Generalitat de Catalunya, economical support from CERCA Program/Generalitat de Catalunya, Fundació Internacional Josep Carreras and from Celgene Spain. The research leading to this invention has received funding from ‘la Caixa’ Foundation. Laura Palomo and Jesus Maria Hernandez‐Sanchez are supported with a research grant by FEHH (Fundación Española de Hematología y Hemoterapia).Peer reviewe