scholarly journals Insights into the involvement of spliceosomal mutations in myelodysplastic disorders from an analysis of SACY-1/DDX41 in Caenorhabditis elegans

2019 ◽  
Author(s):  
Tatsuya Tsukamoto ◽  
Micah D. Gearhart ◽  
Seongseop Kim ◽  
Gemechu Mekonnen ◽  
Caroline A. Spike ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
Hematological Malignancies ◽  
Molecular Genetic ◽  
Molecular Genetic Analysis ◽  
Missense Mutations ◽  
C Elegans ◽  
Dead Box ◽  
Acute Myeloid

ABSTRACTMutations affecting spliceosomal proteins are frequently found in hematological malignancies, including myelodysplastic syndromes and acute myeloid leukemia. DDX41/Abstrakt is a metazoan-specific spliceosomal DEAD-box RNA helicase found to be recurrently mutated in inherited myelodysplastic syndromes and in relapsing cases of acute myeloid leukemia. The genetic properties and genomic impacts of disease-causing missense mutations in DDX41 and other spliceosomal proteins have been uncertain. Here we conduct a comprehensive molecular genetic analysis of the C. elegans DDX41 ortholog, SACY-1. Our results reveal general essential functions for SACY-1 in both the germline and the soma, as well as specific functions affecting germline sex determination and cell cycle control. Certain sacy-1/DDX41 mutations, including the R525H human oncogenic variant, confer antimorphic activity, suggesting that they compromise the function of the spliceosome. Consistent with these findings, sacy-1 exhibits synthetic lethal interactions with several spliceosomal components, and biochemical analyses suggest that SACY-1 is a component of the C. elegans spliceosome. We used the auxin-inducible degradation system to analyze the impact of SACY-1 on the transcriptome using RNA sequencing. SACY-1 depletion impacts the transcriptome through splicing-independent and splicing-dependent mechanisms. The observed transcriptome changes suggest that disruption of spliceosomal function induces a stress response. Altered 3’ splice site usage represents the predominant splicing defect observed upon SACY-1 depletion, consistent with a role for SACY-1 as a second-step splicing factor. Missplicing events appear more prevalent in the soma than the germline, suggesting that surveillance mechanisms protect the germline from aberrant splicing.Author SummaryMutations affecting spliceosomal proteins are frequently found in hematological malignancies. DDX41/Abstrakt is a metazoan-specific spliceosomal DEAD-box RNA helicase recurrently mutated in inherited and relapsing myelodysplastic syndromes and acute myeloid leukemia. The genetic properties and genomic impacts of disease-causing mutations in spliceosomal proteins have been uncertain. Here we conduct a comprehensive molecular genetic analysis of the C. elegans DDX41 ortholog, SACY-1. Our results reveal that multiple sacy-1/DDX41 missense mutations, including the R525H human oncogenic variant, exhibit antimorphic activity that likely compromises the function of the spliceosome. The genomic consequences of SACY-1 depletion include splicing-splicing-independent and splicing-dependent alterations in the transcriptome.

scholarly journals Nuclear Inositides and Inositide-Dependent Signaling Pathways in Myelodysplastic Syndromes

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 697 ◽  
Author(s):  
Jie Xian ◽  
Eric Owusu Obeng ◽  
Stefano Ratti ◽  
Isabella Rusciano ◽  
Maria Vittoria Marvi ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Signaling Pathways ◽  
Myelodysplastic Syndromes ◽  
Peripheral Blood ◽  
Myeloid Leukemia ◽  
Hematological Malignancies ◽  
Critical Role ◽  
Cellular Events ◽  
Molecular Aspects ◽  
Acute Myeloid

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by peripheral blood cytopenia and abnormal myeloproliferation, as well as a variable risk of evolution into acute myeloid leukemia (AML). The nucleus is a highly organized organelle with several distinct domains where nuclear inositides localize to mediate essential cellular events. Nuclear inositides play a critical role in the modulation of erythropoiesis or myelopoiesis. Here, we briefly review the nuclear structure, the localization of inositides and their metabolic enzymes in subnuclear compartments, and the molecular aspects of nuclear inositides in MDS.

scholarly journals COVID-19 infection in adult patients with hematological malignancies: a European Hematology Association Survey (EPICOVIDEHA)

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Livio Pagano ◽  
Jon Salmanton-García ◽  
Francesco Marchesi ◽  
Alessandro Busca ◽  
Paolo Corradini ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
High Risk ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
Hematological Malignancies ◽  
Multivariable Analysis ◽  
Adverse Outcomes ◽  
Adult Patients ◽  
Smoking History ◽  
Acute Myeloid

Abstract Background Patients with hematological malignancies (HM) are at high risk of mortality from SARS-CoV-2 disease 2019 (COVID-19). A better understanding of risk factors for adverse outcomes may improve clinical management in these patients. We therefore studied baseline characteristics of HM patients developing COVID-19 and analyzed predictors of mortality. Methods The survey was supported by the Scientific Working Group Infection in Hematology of the European Hematology Association (EHA). Eligible for the analysis were adult patients with HM and laboratory-confirmed COVID-19 observed between March and December 2020. Results The study sample includes 3801 cases, represented by lymphoproliferative (mainly non-Hodgkin lymphoma n = 1084, myeloma n = 684 and chronic lymphoid leukemia n = 474) and myeloproliferative malignancies (mainly acute myeloid leukemia n = 497 and myelodysplastic syndromes n = 279). Severe/critical COVID-19 was observed in 63.8% of patients (n = 2425). Overall, 2778 (73.1%) of the patients were hospitalized, 689 (18.1%) of whom were admitted to intensive care units (ICUs). Overall, 1185 patients (31.2%) died. The primary cause of death was COVID-19 in 688 patients (58.1%), HM in 173 patients (14.6%), and a combination of both COVID-19 and progressing HM in 155 patients (13.1%). Highest mortality was observed in acute myeloid leukemia (199/497, 40%) and myelodysplastic syndromes (118/279, 42.3%). The mortality rate significantly decreased between the first COVID-19 wave (March–May 2020) and the second wave (October–December 2020) (581/1427, 40.7% vs. 439/1773, 24.8%, p value < 0.0001). In the multivariable analysis, age, active malignancy, chronic cardiac disease, liver disease, renal impairment, smoking history, and ICU stay correlated with mortality. Acute myeloid leukemia was a higher mortality risk than lymphoproliferative diseases. Conclusions This survey confirms that COVID-19 patients with HM are at high risk of lethal complications. However, improved COVID-19 prevention has reduced mortality despite an increase in the number of reported cases.

scholarly journals Altered Spatial Composition of the Immune Cell Repertoire in Association to CD34+ Blasts in Myelodysplastic Syndromes and Secondary Acute Myeloid Leukemia

Cancers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 186
Author(s):  
Marcus Bauer ◽  
Christoforos Vaxevanis ◽  
Haifa Kathrin Al-Ali ◽  
Nadja Jaekel ◽  
Christin Le Hoa Naumann ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
Multispectral Imaging ◽  
Immune Cell ◽  
Genetic Alterations ◽  
Spatial Proximity ◽  
Secondary Acute Myeloid Leukemia ◽  
Acute Myeloid

Background: Myelodysplastic syndromes (MDS) are caused by a stem cell failure and often include a dysfunction of the immune system. However, the relationship between spatial immune cell distribution within the bone marrow (BM), in relation to genetic features and the course of disease has not been analyzed in detail. Methods: Histotopography of immune cell subpopulations and their spatial distribution to CD34+ hematopoietic cells was determined by multispectral imaging (MSI) in 147 BM biopsies (BMB) from patients with MDS, secondary acute myeloid leukemia (sAML), and controls. Results: In MDS and sAML samples, a high inter-tumoral immune cell heterogeneity in spatial proximity to CD34+ blasts was found that was independent of genetic alterations, but correlated to blast counts. In controls, no CD8+ and FOXP3+ T cells and only single MUM1p+ B/plasma cells were detected in an area of ≤10 μm to CD34+ HSPC. Conclusions: CD8+ and FOXP3+ T cells are regularly seen in the 10 μm area around CD34+ blasts in MDS/sAML regardless of the course of the disease but lack in the surrounding of CD34+ HSPC in control samples. In addition, the frequencies of immune cell subsets in MDS and sAML BMB differ when compared to control BMB providing novel insights in immune deregulation.

scholarly journals Post-transplantation cyclophosphamide reduces the incidence of acute graft-versus-host disease in patients with acute myeloid leukemia/myelodysplastic syndromes who receive immune checkpoint inhibitors after allogeneic hematopoietic stem cell transplantation

2021 ◽  
Vol 9 (2) ◽  
pp. e001818 ◽  
Author(s):  
Chantal Saberian ◽  
Noha Abdel-Wahab ◽  
Ala Abudayyeh ◽  
Hind Rafei ◽  
Jacinth Joseph ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Stem Cell ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
Acute Gvhd ◽  
Checkpoint Inhibitors ◽  
Post Transplantation ◽  
Hematopoietic Stem ◽  
Gvhd Prophylaxis ◽  
Acute Myeloid

BackgroundImmune checkpoint inhibitors (ICIs) are being used after allogeneic hematopoietic stem cell transplantation (alloHCT) to reverse immune dysfunction. However, a major concern for the use of ICIs after alloHCT is the increased risk of graft-versus-host disease (GVHD). We analyzed the association between GVHD prophylaxis and frequency of GVHD in patients who had received ICI therapy after alloHCT.MethodsA retrospective study was performed in 21 patients with acute myeloid leukemia (n=16) or myelodysplastic syndromes (n=5) who were treated with antiprogrammed cell death protein 1 (16 patients) or anticytotoxic T lymphocyte-associated antigen 4 (5 patients) therapy for disease relapse after alloHCT. Associations between the type of GVHD prophylaxis and incidence of GVHD were analyzed.ResultsFour patients (19%) developed acute GVHD. The incidence of acute GVHD was associated only with the type of post-transplantation GVHD prophylaxis; none of the other variables included (stem cell source, donor type, age at alloHCT, conditioning regimen and prior history of GVHD) were associated with the frequency of acute GVHD. Twelve patients received post-transplantation cyclophosphamide (PTCy) for GVHD prophylaxis. Patients who received PTCy had a significantly shorter median time to initiation of ICI therapy after alloHCT compared with patients who did not receive PTCy (median 5.1 months compared with 26.6 months). Despite early ICI therapy initiation, patients who received PTCy had a lower observed cumulative incidence of grades 2–4 acute GVHD compared with patients who did not receive PTCy (16% compared with 22%; p=0.7). After controlling for comorbidities and time from alloHCT to ICI therapy initiation, the analysis showed that PTCy was associated with a 90% reduced risk of acute GVHD (HR 0.1, 95% CI 0.02 to 0.6, p=0.01).ConclusionsICI therapy for relapsed acute myeloid leukemia/myelodysplastic syndromes after alloHCT may be a safe and feasible option. PTCy appears to decrease the incidence of acute GVHD in this cohort of patients.

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