Sideroblasts Research Articles

P116 - Topic: AS07-Singular Entities/Subtypes/AS07d-MDS with ring sideroblasts: SF3B1 MUTATIONS AND THEIR IMPACT ON CELLULAR BIOENERGETICS IN MYELODYSPLASTIC SYNDROMES

P116 - Topic: AS07-Singular Entities/Subtypes/AS07d-MDS with ring sideroblasts: SF3B1 MUTATIONS AND THEIR IMPACT ON CELLULAR BIOENERGETICS IN MYELODYSPLASTIC SYNDROMES

Clinical characteristics of Japanese patients with myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis.

Myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T) is a rare disease, which presents with features of myelodysplastic syndromes with ring sideroblasts and essential thrombocythemia, as well as anemia and marked thrombocytosis. SF3B1 and JAK2 mutations are often found in patients, and are associated with their specific clinical features. This study was a retrospective analysis of 34 Japanese patients with MDS/MPN-RS-T. Median age at diagnosis was 77 (range, 51-88) years, and patients had anemia (median hemoglobin: 9.0g/dL) and thrombocytosis (median platelet count: 642 × 109/L). Median overall survival was 70 (95% confidence interval: 68-not applicable) months during the median follow-up period of 26 (range: 0-91) months. A JAK2V617F mutation was detected in 46.2% (n = 12) of analyzed patients (n = 26), while an SF3B1 mutation was detected in 87.5% (n = 7) of analyzed patients (n = 8). Like those with myelodysplastic syndromes or myeloproliferative neoplasms, patients often received erythropoiesis-stimulating agents and aspirin to improve anemia and prevent thrombosis. This study, which was the largest to describe the real-world characteristics of Japanese patients with MDS/MPN-RS-T, showed that the patients had similar characteristics to those in western countries.

5612976 FIRST ADMINISTRATION OF HYPOXIC BLOOD IN A TRANSFUSION-DEPENDENT PATIENT

Background: Many patients with inherited and acquired anemias such as sickle cell disease, thalassemia and myelodysplastic syndromes (MDS) are transfusion-dependent, requiring regularly scheduled red blood cell (RBC) transfusions.1 Chronic transfusions are associated with a range of complications, such as transfusion-related adverse events (AEs) and iron overload.1 Frequent transfusions may also have a negative impact on patient quality of life (QoL)1 and access is often difficult. To reduce transfusion burden in dependent patients, Hemanext Inc. (Lexington, MA, United States) has developed a CE mark certified device to process and store red blood cells hypoxically - CPD/PAGGSM leukocytes-reduced (LR), O2/CO2 reduced.2 By reducing oxidative stress, hypoxic blood storage has been shown to improve the quality and function of RBCs,3 demonstrating that lower volumes of hypoxic RBCs are required to resuscitate from hemorrhagic shock and maintain hemodynamics than conventional RBCs in animal models.4 This may have several benefits in transfusion-dependent patients, including increasing the interval between transfusions and hence potential to reduce iron overload. Aims/Methods: A pilot clinical study in Norway is investigating the safety of a single administration of hypoxic RBCs in patients with hematologic malignancies and patients with burns. The primary outcome of the study is the occurrence of AEs at Day 7±1 post-transfusion. Secondary outcomes include assessment of AEs from enrollment to subsequent RBC transfusion (or Day 28) and the evolution of hemoglobin (Hb) levels pre- and post-transfusion. For the subset of patients with hematologic malignancies, the transfusion trigger is set to Hb <9.0 g/dL, and two units of hypoxic RBCs are administered. Results: In August 2022, following his informed consent, the first patient was transfused with hypoxic RBCs; this patient was also the first to receive hypoxic blood within Hemanext’s overall clinical program. The patient was an 80-year-old man who initially presented with anemia and diagnostic workup revealed bone marrow smear with morphological features of erythroid dysplasia with ring sideroblasts in 30% of cells and mutation in the SF3B1 gene. After initial response to treatment, he became transfusion-dependent, and has received 2 RBC units every 2 weeks for a year. The patient had a pre-transfusion Hb level of 8.1 g/dL and received 2 units of O+ hypoxic RBCs over 2 hours without any complications. No adverse events were recorded on Day 1 and the patient experienced no adverse events by Day 7. Further outcomes will be reported. Conclusion: Hypoxic RBCs processed with the CPD/PAGGSM LR, O2/CO2 reduced system were well tolerated in this patient; Hb level was within the target range at follow-up, supporting that hypoxically stored RBCs function appropriately. The study is ongoing and will continue to assess hypoxic RBCs in patients with hematologic malignancies and patients with burns. Enrolment within the wider clinical program – including studies investigating hypoxic RBC administration in patients with thalassemia in Italy and sickle cell disease in the US – is planned.

Danazol Treatment for Thrombocytopenia in Myelodysplastic Syndromes: Can an "Old-fashioned" Drug be Effective?

Danazol Treatment for Thrombocytopenia in Myelodysplastic Syndromes: Can an "Old-fashioned" Drug be Effective?

Recurrent Mutations of the Active Adenylation Domain of UBA1 in Atypical Form of VEXAS Syndrome.

Recurrent Mutations of the Active Adenylation Domain of UBA1 in Atypical Form of VEXAS Syndrome.

Three siblings with variable degrees of neuromuscular involvement and congenital sideroblastic anemia: A peculiar phenotype and a surprise genotypic explanation.

Congenital sideroblastic anemias (CSAs) are a group of inherited bone-marrow disorders manifesting with erythroid hyperplasia and ineffective erythropoiesis. We describe a detailed clinical and genetic characterization of three siblings with CSA. Two of them had limb-girdle myopathy and global developmental delay. The two elder siblings performed allogenic hematopoietic stem-cell transplantation 5 and 3 years prior with stabilization of the hematological features. Exome sequencing in the non-transplanted sibling revealed a novel homozygous nonsense variant in SLC25A38 gene NM_017875.2:c.559C>T; p.(Arg187*) causing autosomal-recessive sideroblastic anemia type-2, and a second homozygous pathogenic previously reported variant in GMPPB gene NM_013334.3:c.458C>T; p.(Thr153Ile) causing autosomal-recessive muscular dystrophy-dystroglycanopathy type B14. With the established diagnosis, hematopoietic stem cell transplantation is now being scheduled for the youngest sibling, and a trial therapy with acetylcholine esterase inhibitors was started for the two neurologically affected patients with partial clinical improvement. This family emphasizes the importance of whole-exome sequencing for familial cases with complex phenotypes and vague neurological manifestations.

Severe Microcytic Anemia Caused by Complex Hereditary Spherocytosis and X-Linked Sideroblastic Anemia with Mutations in SPTB and ALAS2 Genes

We report a case of severe anemia caused by complex hereditary spherocytosis (HS) and X-linked sideroblastic anemia (XLSA) with two mutations in the spectrin beta (SPTB) and 5-aminolevulinic acid synthase (ALAS2) genes. The proband was a 16-year-old male with severe jaundice and microcytic hypochromic anemia since his childhood. He had more severe anemia requiring erythrocyte transfusion, and had no response to vitamin B6 treatment. Next-generation sequencing (NGS) revealed double heterozygous mutations, one in exon 19 (c.3936G > A:p.W1312X) of the SPTB gene and another in exon 2 (c.37A > G:p.K13E) of the ALAS2 gene, and confirmed again by Sanger sequencing. The mutation of ALAS2 (c.37A > G) is inherited from his asymptomatic heterozygous mother, causing amino acid p.K13E, and the mutation has not yet been reported. The mutation of SPTB (c.3936G > A) is a nonsense mutation, leading to a premature termination codon in exon 19, and the mutation in the SPTB gene is not found in any of his relatives, which indicates a de novo monoallelic mutation. Conclusions: The double heterozygous mutations in the SPTB and ALAS2 genes lead to the joint occurrence of HS and XLSA in this patient, and are implicated in the more severe clinical phenotypes.

Momelotinib (JAK1/JAK2/ACVR1 inhibitor): mechanism of action, clinical trial reports, and therapeutic prospects beyond myelofibrosis.

Janus kinase (JAK) 2 inhibitors are now part of the therapeutic armamentarium for primary and secondary myelofibrosis (MF). Patients with MF endure shortened survival and poor quality of life. Allogeneic stem cell transplantation (ASCT) is currently the only treatment modality in MF with the potential to cure the disease or prolong survival. By contrast, current drug therapy in MF targets quality of life and does not modify the natural history of the disease. The discovery of JAK2 and other JAK-STAT activating mutations (i.e., CALR and MPL) in myeloproliferative neoplasms, including MF, has facilitated the development of several JAK inhibitors that are not necessarily specific to the oncogenic mutations themselves but have proven effective in countering JAK-STAT signaling, resulting in suppression of inflammatory cytokines and myeloproliferation. This non-specific activity resulted in clinically favorable effects on constitutional symptoms and splenomegaly and, consequently, approval by the Food and Drug Administration (FDA) of three small molecule JAK inhibitors: ruxolitinib, fedratinib, and pacritinib. A fourth JAK inhibitor, momelotinib, is poised for FDA approval soon and has been shown to provide additional benefit in alleviating transfusion-dependent anemia in MF. The salutary effect of momelotinib on anemia has been attributed to inhibition of activin A receptor, type 1 (ACVR1) and recent information suggests a similar effect from pacritinib. ACRV1 mediates SMAD2/3 signaling which contributes to upregulation of hepcidin production and iron-restricted erythropoiesis. Targeting ACRV1 raises therapeutic prospects in other myeloid neoplasms associated with ineffective erythropoiesis, such as myelodysplastic syndromes with ring sideroblasts or SF3B1 mutation, especially those with co-expression of a JAK2 mutation and thrombocytosis.

Vitamin B5 and succinyl-CoA improve ineffective erythropoiesis in SF3B1-mutated myelodysplasia.

Patients with myelodysplastic syndrome and ring sideroblasts (MDS-RS) present with symptomatic anemia due to ineffective erythropoiesis that impedes their quality of life and increases morbidity. More than 80% of patients with MDS-RS harbor splicing factor 3B subunit 1 (SF3B1) mutations, the founder aberration driving MDS-RS disease. Here, we report how mis-splicing of coenzyme A synthase (COASY), induced by mutations in SF3B1, affects heme biosynthesis and erythropoiesis. Our data revealed that COASY was up-regulated during normal erythroid differentiation, and its silencing prevented the formation of erythroid colonies, impeded erythroid differentiation, and precluded heme accumulation. In patients with MDS-RS, loss of protein due to COASY mis-splicing led to depletion of both CoA and succinyl-CoA. Supplementation with COASY substrate (vitamin B5) rescued CoA and succinyl-CoA concentrations in SF3B1mut cells and mended erythropoiesis differentiation defects in MDS-RS primary patient cells. Our findings reveal a key role of the COASY pathway in erythroid maturation and identify upstream and downstream metabolites of COASY as a potential treatment for anemia in patients with MDS-RS.

SOHO State of the Art Updates and Next Questions: Treatment of Lower Risk Myelodysplastic Syndromes.

MDS is a clonal stem cell neoplasm with a spectrum from lower risk disease to short term life threatening higher risk disease. The disease risk is dictated by clinical and molecular features. Majority of MDS patients including lower risk disease unfortunately succumb from disease related complications namely cytopenia. While cytopenias may be mild early upon diagnosis and can be surveilled, ultimately treatment is required. Anemia is the hall mark of disease and most common indication to treat in lower risk MDS. Erythroid stimulating agents are used in the first line setting. Treatment can be a personalized approach as in select patient such as patients with del(5q) and those with ringed sideroblasts, lenalidomide, and luspatercept can be extremely effective respectively at improving cytopenias. Younger patients and hypoplastic MDS have also shown and improved response to immunosuppressive therapy. Hypomethylating agents can be option for patients with higher risk features or thrombocytopenia/neutropenia. Refractory cytopenias still poses frustration as options are limited and there is need to add more treatments to our armamentarium.

Mitochondrial Ferritin in Erythroid Cells from patients with Myelodysplastic Syndrome

Background: The Myelodysplastic syndrome (MDS) is extremely fatal illness whither anaemia is insensitive to any medical management. Aim: In present research, effect of levels of ferritin in serum lying on prospects and continued existence was scrutinize in MDS subjects with no previous record of blood transfuse. Study design: Retrospective. Methods: These cases (MDS) were alienated into two groups, according to their serum ferritin levels. Sample size of 58 cases of MDS calculated according to online service “Select Statistical Services Ltd” comparing two means. Results: The time of endurance mean was 5.09 years ± 4.8 months. Median ferritin levels of serum ferritin were 358 ng /ml. The plasma ferritin level is related with higher rate of mortality with levels as 500 ng/ml. The ROC part for Serum ferritin was 0.721 by means of a cut-off range of 401; susceptibility and explicitness. were 71.7% and 69.1%, correspondingly) P=0.002. In attendance were 33 subjects with value of ferritin is ≥ 500 ng/ml. Patients with serum ferritin values ≥ 500 ng/mL had lower survival expectancy. Ferritin ≥ 500 ng/mL be related with seven folds augmented death rates (P = 0.001). Practical Implication: In MDS iron chelation is not well-known, for that reason the overall survival is not good. The iron chelation might encompass a favorable outcome on survival of MDS. Conclusion: Even though 1000ng/ml ferritin value in the beginning of chelation therapy is adequate, reduced survival expectancy will be associated with high levels of serum ferritin. Keywords: Myelodysplastic syndrome, ferritin, chelation, ring sideroblast, isoniazid, penicillamine

Myelodysplastic syndromes with ring sideroblasts.

Myelodysplastic syndromes (MDS) are acquired bone marrow malignant disorders characterized by ineffective hematopoiesis, resulting from a complex interaction between genetic and epigenetic mutations, alterations of the marrow microenvironment, and the immune system. In 2001, the World Health Organization (WHO) proposed a classification that integrates morphologic and genetic information, considering the MDS with ring sideroblasts (MDS-RS) as a distinct entity. Considering the strong association between MDS-RS and SF3B1 mutation and its importance in the development of MDS, the last WHO classification replaced the prior entity of MDS-RS with MDS with SF3B1 mutation. Several studies were performed to explore this genotype-phenotype correlation. Mutant SF3B1 protein deregulates the expression of genes implicated in developing hematopoietic stem and progenitor cells. Of paramount importance are PPOX and ABCB7 involved in iron metabolism. Another essential role in hemopoiesis is played by the transforming growth factor-beta (TGF-β) receptor. This gene exerts its effects on SMAD pathways, regulating hematopoiesis through effects on balancing proliferation and apoptosis cell inactivity, differentiation, and migration. Luspatercept (ACE-536) is a soluble fusion protein that inhibits molecules in the TGF-β superfamily. Since its structure resembles the TGF-β family receptor, it catches TGF-β superfamily ligands before binding to the receptor, resulting in reduced activation of SMAD signaling, thus enabling erythroid maturation. Luspatercept was investigated in the phase III trial MEDALIST, showing promising efficacy in treating anemia compared to placebo. Nowadays, further studies are needed to explore the real potential of luspatercept, investigating the biological features likely associated with treatment response, the potential use in combination treatments, and its role in the treatment of naïve MDS.

Non-erythropoiesis stimulating agent, non-iron therapies for the management of anemia: A scoping review.

Non-erythropoiesis stimulating agent, non-iron therapies for the management of anemia: A scoping review.

Thalidomide as an Effective Treatment in Sideroblastic Anemia, Immunodeficiency, Periodic Fevers, and Developmental Delay (SIFD)

PurposeSideroblastic anemia, immunodeficiency, periodic fevers, and developmental delay (SIFD) is an autosomal recessive syndrome caused by biallelic loss-of-function variant of tRNA nucleotidyl transferase 1 (TRNT1). Efficacious methods to treat SIFD are lacking. We identified two novel mutations in TRNT1 and an efficacious and novel therapy for SIFD.MethodsWe retrospectively summarized the clinical records of two patients with SIFD from different families and reviewed all published cases of SIFD.ResultsBoth patients had periodic fever, developmental delay, rash, microcytic anemia, and B cell lymphopenia with infections. Whole-exome sequencing of patient 1 identified a previously unreported homozygous mutation of TRNT1 (c.706G > A/p.Glu236Lys). He received intravenous immunoglobulin (IVIG) replacement and antibiotics, but died at 1 year of age. Gene testing in patient 2 revealed compound heterozygous mutations (c.907C > G/p.Gln303Glu and c.88A > G/p.Met30Val) in TRNT1, the former of which is a novel mutation. Periodic fever was controlled in the first month after adalimumab therapy and IVIG replacement, but recurred in the second month. Adalimumab was discontinued and replaced with thalidomide, which controlled the periodic fever and normalized inflammatory markers effectively. A retrospective analysis of reported cases revealed 69 patients with SIFD carrying 46 mutations. The male: female ratio was 1: 1, and the mean age of onset was 3.0 months. The most common clinical manifestations in patients with SIFD were microcytic anemia (82.6%), hypogammaglobulinemia/B cell lymphopenia (75.4%), periodic fever (66.7%), and developmental delay (60.0%). In addition to the typical tetralogy, SIFD features several heterogeneous symptoms involving multiple systems. Corticosteroids, immunosuppressants, and anakinra have low efficacy, whereas etanercept suppressed fever and improved anemia in reports. Bone-marrow transplantation can be used to treat severe SIFD, but carries a high risk. In total, 28.2% (20/71) of reported patients died, mainly because of multi-organ failure. Biallelic mutations located in exon1-intron5 lead to more severe phenotypes and higher mortality. Furthermore, 15.5% (11/71) patients survived to adulthood. The symptoms could be resolved spontaneously in five patients.ConclusionsThalidomide can control the inflammation of SIFD and represents a new treatment for SIFD.

The burden of red blood cell transfusions in patients with lower-risk myelodysplastic syndromes and ring sideroblasts: an analysis of the prospective MDS-CAN registry

Many patients with lower-risk myelodysplastic syndromes (LR MDS) require long-term red blood cell (RBC) transfusions to manage anemia. The consequences of RBC transfusions in LR MDS with ring sideroblasts (LR MDS-RS) are not well known. We estimated the association between cumulative RBC dose density and clinical and patient-reported outcomes using data from the MDS-CAN registry for patients enrolled between January 2008 and December 2018. Outcomes included overall survival, hospitalization, and health-related quality of life (HRQoL). A total of 145 enrolled patients with LR MDS and RS ≥5% had a median follow-up time of 27.1 months; 45 had no transfusions during follow-up, 51 had <1 transfusion per month, and 49 had ≥1 transfusion per month. The cumulative density of RBC transfusions was associated with significantly greater mortality, hospitalization, and inferior HRQoL, suggesting that exposure to RBC transfusion may constitute a significant treatment burden in patients with LR MDS-RS.

JAK2 Mutations Are Rare and Diverse in Myelodysplastic Syndromes: Case Series and Review of the Literature

To investigate and characterize JAK2 mutations in myelodysplastic syndrome (MDS), we present three cases with diverse JAK2 mutations and review the literature. The institutional SoftPath software was used to find MDS cases between January 2020 and April 2022. The cases with a diagnosis of a myelodysplastic/myeloproliferative overlap syndrome including MDS/MPN with ring sideroblasts and thrombocytosis were excluded. The cases with molecular data by next generation sequencing looking for gene aberrations commonly seen in myeloid neoplasms were reviewed for the detection of JAK2 mutations including variants. A literature review on the identification, characterization, and significance of JAK2 mutations in MDS was performed. Among 107 cases of the MDS reviewed, a JAK2 mutation was present in three cases, representing 2.8% of the overall cases. A JAK2 V617F mutation was found in one case representing slightly less than 1% of all the MDS cases. In addition, we found JAK2 R564L and JAK2 I670V point mutation variants to be associated with a myelodysplastic phenotype. JAK2 mutations in MDS are rare and represent less than 3% of cases. It appears that JAK2 variant mutations in MDS are diverse and further studies are needed to understand their role in the phenotype and prognosis of the disease.

Improved benefit of continuing luspatercept therapy: sub-analysis of patients with lower-risk MDS in the MEDALIST study

Red blood cell transfusion independence (RBC-TI) is an important goal in treating lower-risk myelodysplastic syndromes with ring sideroblasts. In the phase 3 MEDALIST study, RBC-TI of ≥ 8 weeks was achieved by significantly more luspatercept- versus placebo-treated patients in the first 24 weeks of treatment. In this post hoc analysis, we evaluated RBC transfusion units and visits based on patients’ baseline transfusion burden level and the clinical benefit of luspatercept treatment beyond week 25 in initial luspatercept nonresponders (patients who did not achieve RBC-TI ≥ 8 weeks by week 25) but continued luspatercept up to 144 weeks. RBC transfusion burden, erythroid response, serum ferritin levels, and hemoglobin levels relative to baseline were evaluated. Through week 25, fewer RBC transfusion units and visits were observed in luspatercept-treated patients versus placebo, regardless of baseline transfusion burden. This continued through 144 weeks of luspatercept treatment, particularly in patients with low baseline transfusion burden. Sixty-eight patients were initial nonresponders at week 25 but continued treatment; most (81%) received the maximum dose of luspatercept (1.75 mg/kg). Sixteen percent achieved RBC-TI for ≥ 8 weeks during weeks 25–48, 26% had reduced RBC transfusion burden, 10% achieved an erythroid response, 44% had reduced serum ferritin, and hemoglobin levels increased an average of 1.3 g/dL from baseline. These data have implications for clinical practice, as transfusion units and visits are less in luspatercept-treated patients through week 25 regardless of baseline transfusion burden, and continuing luspatercept beyond week 25 can potentially provide additional clinical benefits for initial nonresponders. Trial registration: NCT02631070.

Role of Luspatercept in the Management of Lower-Risk Myelodysplastic Syndromes.

Treatment options are limited for patients with anemia associated with lower-risk myelodysplastic syndromes (LR-MDS). The recent approval of luspatercept for the treatment of anemia associated with very low-to intermediate-risk MDS with ring sideroblasts (RS) or with myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis has provided adult patients and practitioners with a much-needed new therapeutic option. Luspatercept is a first-in-class erythroid maturation agent that exerts its effects on later stages of erythropoiesis. In the phase III MEDALIST trial of patients with LR-MDS with RS, luspatercept (starting dose 1 mg/kg) demonstrated substantial clinical benefit (38% of patients treated with luspatercept vs. 13% of those treated with placebo [p < .001] achieved transfusion independence for ≥ 8 weeks during the first 24 weeks of treatment) and a favorable safety profile. The most common adverse events (AEs), including fatigue, asthenia, dizziness, and diarrhea, were more frequent during the first 4 treatment cycles and subsequently declined. This review provides a comprehensive overview of luspatercept treatment administration, including the mechanism of action, efficacy and safety data, management of dosing, and AEs associated with luspatercept treatment of patients with LR-MDS.

P609: Prenatal diagnosis of sideroblastic anemia with immunodeficiency, fevers, and developmental delay in a fetus with severe growth restriction and cardiomegaly*

P609: Prenatal diagnosis of sideroblastic anemia with immunodeficiency, fevers, and developmental delay in a fetus with severe growth restriction and cardiomegaly*

Clinico-genetic and prognostic analyses of 716 patients with primary myelodysplastic syndrome and myelodysplastic syndrome/acute myeloid leukemia based on the 2022 International Consensus Classification.

The 2022 International Consensus Classification (ICC) recategorized myeloid neoplasms based on recent advances in the understanding of the biology of hematologic malignancies, in which myelodysplastic syndrome (MDS) with blasts of 10%-19% is classified as MDS/acute myeloid leukemia (AML), MDS with mutated SF3B1, irrespective of the number of ring sideroblasts, as MDS-SF3B1, and those with multi-hit TP53 mutations as MDS with mutated TP53. In the analysis of 716 patients with MDS diagnosed according to the 2016 WHO classification, we found that 75.3% of patients remained in the MDS group based on the ICC, while 24.7% of patients were reclassified to the MDS/AML group after the exclusion of 15 patients who were classified to the AML group. Patients with MDS/AML showed a distinct mutational landscape and had poorer outcomes, compared to those with MDS. In the MDS group, patients with MDS-SF3B1 had higher frequencies of DNMT3A and TET2 mutations than those with MDS, not otherwise specified, with single lineage dysplasia or multilineage dysplasia. Patients with mutated TP53 were associated with dismal outcomes, irrespective of the blast percentage. In conclusion, this study showed that the ICC facilitates efficient segregation and risk-stratification of MDS which can help guide the treatment choice of patients with the disease.