scholarly journals Nonsense Suppression Therapy: New Hypothesis for the Treatment of Inherited Bone Marrow Failure Syndromes

2020 ◽  
Vol 21 (13) ◽  
pp. 4672 ◽  
Author(s):  
Valentino Bezzerri ◽  
Martina Api ◽  
Marisole Allegri ◽  
Benedetta Fabrizzi ◽  
Seth J. Corey ◽  
...  

Inherited bone marrow failure syndromes (IBMFS) are a group of cancer-prone genetic diseases characterized by hypocellular bone marrow with impairment in one or more hematopoietic lineages. The pathogenesis of IBMFS involves mutations in several genes which encode for proteins involved in DNA repair, telomere biology and ribosome biogenesis. The classical IBMFS include Shwachman–Diamond syndrome (SDS), Diamond–Blackfan anemia (DBA), Fanconi anemia (FA), dyskeratosis congenita (DC), and severe congenital neutropenia (SCN). IBMFS are associated with high risk of myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), and solid tumors. Unfortunately, no specific pharmacological therapies have been highly effective for IBMFS. Hematopoietic stem cell transplantation provides a cure for aplastic or myeloid neoplastic complications. However, it does not affect the risk of solid tumors. Since approximately 28% of FA, 24% of SCN, 21% of DBA, 20% of SDS, and 17% of DC patients harbor nonsense mutations in the respective IBMFS-related genes, we discuss the use of the nonsense suppression therapy in these diseases. We recently described the beneficial effect of ataluren, a nonsense suppressor drug, in SDS bone marrow hematopoietic cells ex vivo. A similar approach could be therefore designed for treating other IBMFS. In this review we explain in detail the new generation of nonsense suppressor molecules and their mechanistic roles. Furthermore, we will discuss strengths and limitations of these molecules which are emerging from preclinical and clinical studies. Finally we discuss the state-of-the-art of preclinical and clinical therapeutic studies carried out for IBMFS.

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 298-298
Author(s):  
Hengjun Chao ◽  
Johnson M. Liu

Abstract Introduction: Aged hematopoietic stem cells (HSCs) are known to functionally decline and are prone to development of myeloid malignancies. Recent work has highlighted the twin roles of replication stress and decreased ribosome biogenesis as drivers for the accumulation of DNA damage and senescence. Certain bone marrow failure syndromes, including Shwachman-Diamond syndrome (SDS), Diamond-Blackfan anemia (DBA), and the acquired 5q- syndrome, are characterized by defects in ribosome biogenesis. Furthermore, recent work has suggested a role for p53 activation, through the 5S ribonucleoprotein particle (RNP), in driving cells to senescence following perturbation of ribosome biogenesis. Methods and Results: Here, we have used multiplexing flow cytometry protocols to define, enumerate, and characterize hematopoietic cells of distinct differentiation stages and lineages in 2 DBA cord bloods and 4 adult bone marrows (2 SDS, 1 DBA, and 1 patient with a diminutive somatic deletion of 5q: ages 27, 32, 40, and 30, respectively), as compared with 4 normal cord bloods and 6 normal adult bone marrows. We included a patient with bona fide MDS (diminutive somatic deletion of 5q including RPS14 in a young adult) to compare with the SDS and DBA patients, who do not meet criteria for MDS. Our preliminary results revealed significant defects in the primitive HSC and multipotent progenitor (MPP) compartments in both DBA and SDS. Specifically, we found in DBA and SDS bone marrow and cord blood samples (compared to normal controls): significantly decreased numbers of primitive HSCs (Lin-CD34+CD133+CD38-CD45RA-CD49f+CD90+) and MPPs (Lin-CD34+CD133+CD38-CD45RA-CD49f-CD90-); increased levels of apoptosis and dysregulated proliferation; and G0-1/S cell cycle arrest. We also found significant increases in senescence-associated β-galactosidase staining and G0-1/S cell cycle arrest in Lin-CD34+ and Lin-CD34+CD38-CD133+ subpopulations in all 4 adult patient bone marrows, as compared with normal adult bone marrows processed in identical fashion [see Fig. 1 for representative data from Lin-CD34+CD133+ hematopoietic progenitor cells (HPCs) from one SDS patient]. Foci of the phosphorylated form of the variant histone H2AX (γH2AX) mark DNA damage, and γH2AX staining was similarly increased in comparison to controls (Fig. 1). The mechanism whereby disturbed ribosome biogenesis induces senescence has been suggested as involving 5S RNP-mediated p53 activation. However, our experiments did not demonstrate increased levels of p53 in the SDS patient marrows, as assessed by intracellular staining. Levels of p16, a well known marker of senescence, were markedly increased in the SDS patient samples, when compared to controls. Finally, in the 2 DBA cord bloods analyzed, there was increased senescence-associated β-galactosidase staining but to a lesser degree than in the adult bone marrow samples (as might be expected with temporal progression). Discussion: Taken together, our data suggest that ribosomopathies (which often present in childhood) are disorders of premature senescence. Consequent DNA damage accumulation and decreased repair and compensation may account for the development of MDS and acute myeloid leukemia, disorders seen in young ribosomopathy patients that ordinarily are rare in the general pediatric and young adult population. Disclosures No relevant conflicts of interest to declare.


Hematology ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. 390-398
Author(s):  
Haruna Batzorig Choijilsuren ◽  
Yeji Park ◽  
Moonjung Jung

Abstract Inherited bone marrow failure syndromes (IBMFS) cause hematopoietic stem progenitor cell (HSPC) failure due to germline mutations. Germline mutations influence the number and fitness of HSPC by various mechanisms, for example, abnormal ribosome biogenesis in Shwachman-Diamond syndrome and Diamond-Blackfan anemia, unresolved DNA cross-links in Fanconi anemia, neutrophil maturation arrest in severe congenital neutropenia, and telomere shortening in short telomere syndrome. To compensate for HSPC attrition, HSPCs are under increased replication stress to meet the need for mature blood cells. Somatic alterations that provide full or partial recovery of functional deficit implicated in IBMFS can confer a growth advantage. This review discusses results of recent genomic studies and illustrates our new understanding of mechanisms of clonal evolution in IBMFS.


Gene Therapy ◽  
2021 ◽  
Author(s):  
Jeremy Epah ◽  
Richard Schäfer

AbstractHematopoietic stem cell transplantation (HSCT) is the therapeutic concept to cure the blood/immune system of patients suffering from malignancies, immunodeficiencies, red blood cell disorders, and inherited bone marrow failure syndromes. Yet, allogeneic HSCT bear considerable risks for the patient such as non-engraftment, or graft-versus host disease. Transplanting gene modified autologous HSCs is a promising approach not only for inherited blood/immune cell diseases, but also for the acquired immunodeficiency syndrome. However, there is emerging evidence for substantial heterogeneity of HSCs in situ as well as ex vivo that is also observed after HSCT. Thus, HSC gene modification concepts are suggested to consider that different blood disorders affect specific hematopoietic cell types. We will discuss the relevance of HSC heterogeneity for the development and manufacture of gene therapies and in exemplary diseases with a specific emphasis on the key target HSC types myeloid-biased, lymphoid-biased, and balanced HSCs.


2020 ◽  
Vol 4 (21) ◽  
pp. 5540-5546
Author(s):  
Laurent Schmied ◽  
Patricia A. Olofsen ◽  
Pontus Lundberg ◽  
Alexandar Tzankov ◽  
Martina Kleber ◽  
...  

Abstract Acquired aplastic anemia and severe congenital neutropenia (SCN) are bone marrow (BM) failure syndromes of different origin, however, they share a common risk for secondary leukemic transformation. Here, we present a patient with severe aplastic anemia (SAA) evolving to secondary chronic neutrophilic leukemia (CNL; SAA-CNL). We show that SAA-CNL shares multiple somatic driver mutations in CSF3R, RUNX1, and EZH2/SUZ12 with cases of SCN that transformed to myelodysplastic syndrome or acute myeloid leukemia (AML). This molecular connection between SAA-CNL and SCN progressing to AML (SCN-AML) prompted us to perform a comparative transcriptome analysis on nonleukemic CD34high hematopoietic stem and progenitor cells, which showed transcriptional profiles that resemble indicative of interferon-driven proinflammatory responses. These findings provide further insights in the mechanisms underlying leukemic transformation in BM failure syndromes.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2827-2827
Author(s):  
Akiko Nakamura ◽  
Tsutomu Shichishima ◽  
Hideyoshi Noji ◽  
Kazuhiko Ikeda ◽  
Yukio Maruyama

Abstract PNH is one disorder of bone marrow failure syndromes, including aplastic anemia and myelodysplastic syndrome. It is considered that immunologic mechanisms by cytotoxic T lymphocytes (CTLs) and interferon-γ (IFN-γ) contribute to hypoplastic bone marrow of these disorders. In addition, PNH is an acquired clonal disorder of the hematopoietic stem cell. Recently, it has been reported that analysis of T cell-antigen receptor (TCR)-Vβ repertoires, especially TCR-Vβ CDR3 (complementarity- determining region 3) spectrotypes, is an effective tool to study immunologic mechanisms by CTLs in pathophysiology of PNH (Karadimitris et al, Blood, 2000; Kook et al, Blood, 2002; Risitano et al, Blood, 2002). In the present study, we investigated 21 kinds of TCR-Vβ repertoires by flow cytometry in CD4 and CD8 lymphocytes from 5 PNH patients and a healthy volunteer and the TCR-Vβ CDR3 spectrotypes using polymerase chain reaction assay in CD4 and CD8 lymphocytes from 3 of 5 PNH patients and the control. We also quantitated intracellular IFN-γ in CD4 and CD8 lymphocytes from 5 PNH patients and the control according to the method by Sloand et al (Blood, 2002). We found no specific TCR-Vβ repertoires in CD4 and CD8 lymphocytes from PNH patients compared with the control. The TCR-Vβ repertoires with relative increase of CD4 or CD8 lymphocytes (over 10 of ratio of the proportion of each TCR-Vβ repertoire in a PNH patient/the proportion of the same TCR-Vβ repertoire in a healthy volunteer) were 13.6 or 4 and 22 in Case 1, 3 and 11 or 1 in Case 2, 3 and 13.6 or 3 in Case 3, 5.3 and 7.2 or 2, 3, 7, and 18 in Case 4, and 4, 5.2, 13.6, 16, and 23 or 1 and 14 in Case 5, respectively. TCR-Vβ CDR3 spectrotyping showed that in CD4 lymphocytes most CDR3 patterns were chiefly polyclonal, except for one oligoclonal (Case 1) and one monoclonal (Case 3) patterns of TCR-Vβ25; in CD8 lymphocytes most CDR3 consisted of polyclonal, oligoclonal, and/or monoclonal patterns, suggesting the possibility that CD8 lymphocytes recognize much more antigens of abnormal cells, probably including PNH clones, than CD4 lymphocytes. Unfortunately, we found the same patterns as described above in CD8 lymphocytes from the control, although CD4 lymphocytes from the control presented only polyclonal pattern of CDR3. Quantitative analyses of IFN-γ showed that index values of IFN-γ in CD4 and CD8 lymphocytes from PNH patients were higher than those from the control. However, we did not find any significant correlations between the spectrotypes of TCR-Vβ CDR3 and the index values of IFN-γ in PNH patients, suggesting that TCR-Vβ repertoires with monoclonal and oligoclonal CDR3 patterns do not necessarily produce much IFN-γ. In conclusion, our findings suggest that TCR-Vβ CDR3 spectrotyping is more effective tool to resolve some immune mechanisms of pathophysiology in PNH, especially by auto-reactive CTLs.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4793-4793
Author(s):  
Hasan Ahmed Abdel-ghaffar ◽  
Hosam Zaghloul ◽  
Ahmed El-Waseef ◽  
Mohamed El-Naggar ◽  
Mohamed Mabed ◽  
...  

Abstract Background and aim of the work: Bone marrow failure syndromes (BMFS) includes inherited and acquired conditions. Inherited bone marrow failure includes a number of syndromes; with Fanconi anemia (FA) being the most common one of them. Telomeres are eroded with cell division, but in hematopoietic stem cell, maintenance of their length is mediated by telomerase. Short telomeres can result in instability of cell function where diseases occur. Bone Marrow Failure might be developed due to low telomerase activity or short telomeres. Our study is aiming to evaluate the utility of Real Time Quantitative-Polymerase Chain Reaction (RT-qPCR) in measuring the relative telomere length and its significance in diagnosis and prognosis of patients with BMFS. Materials and methods: The study includes 3 groups: A group of congenital BMF (29 patients), a group of acquired BMF (10 patients) and a third control group (15 cases). The relative telomere length is evaluated for them using RT-qPCR. Results: We have found that there is a significant difference in relative telomere length between congenital group and controls (p=0.001), also a significant difference between acquired group and controls (p= 0.029). However, there is no significant difference between congenital and acquired groups (p= 0.479). There is no significant correlation between the telomere length and the overall survival or prognosis of the patients of BMFS. Conclusion: We conclude that the telomere length is significantly altered in patients with BMFS whether being congenital or acquired compared to the control group. Disclosures No relevant conflicts of interest to declare.


2021 ◽  
Vol 5 (16) ◽  
pp. 3216-3226
Author(s):  
Yash B. Shah ◽  
Salvatore F. Priore ◽  
Yimei Li ◽  
Chi N. Tang ◽  
Peter Nicholas ◽  
...  

Abstract Acquired aplastic anemia (AA) is a life-threatening bone marrow aplasia caused by the autoimmune destruction of hematopoietic stem and progenitor cells. There are no existing diagnostic tests that definitively establish AA, and diagnosis is currently made via systematic exclusion of various alternative etiologies, including inherited bone marrow failure syndromes (IBMFSs). The exclusion of IBMFSs, which requires syndrome-specific functional and genetic testing, can substantially delay treatment. AA and IBMFSs can have mimicking clinical presentations, and their distinction has significant implications for treatment and family planning, making accurate and prompt diagnosis imperative to optimal patient outcomes. We hypothesized that AA could be distinguished from IBMFSs using 3 laboratory findings specific to the autoimmune pathogenesis of AA: paroxysmal nocturnal hemoglobinuria (PNH) clones, copy-number–neutral loss of heterozygosity in chromosome arm 6p (6p CN-LOH), and clonal T-cell receptor (TCR) γ gene (TRG) rearrangement. To test our hypothesis, we determined the prevalence of PNH, acquired 6p CN-LOH, and clonal TRG rearrangement in 454 consecutive pediatric and adult patients diagnosed with AA, IBMFSs, and other hematologic diseases. Our results indicated that PNH and acquired 6p CN-LOH clones encompassing HLA genes have ∽100% positive predictive value for AA, and they can facilitate diagnosis in approximately one-half of AA patients. In contrast, clonal TRG rearrangement is not specific for AA. Our analysis demonstrates that PNH and 6p CN-LOH clones effectively distinguish AA from IBMFSs, and both measures should be incorporated early in the diagnostic evaluation of suspected AA using the included Bayesian nomogram to inform clinical application.


Hematology ◽  
2017 ◽  
Vol 2017 (1) ◽  
pp. 96-101 ◽  
Author(s):  
Rodrigo T. Calado ◽  
Diego V. Clé

Abstract Despite significant progress in transplantation by the addition of alternative hematopoietic stem cell sources, many patients with inherited bone marrow failure syndromes are still not eligible for a transplant. In addition, the availability of sequencing panels has significantly improved diagnosis by identifying cryptic inherited cases. Androgens are the main nontransplant therapy for bone marrow failure in dyskeratosis congenita and Fanconi anemia, reaching responses in up to 80% of cases. Danazol and oxymetholone are more commonly used, but virilization and liver toxicity are major adverse events. Diamond-Blackfan anemia is commonly treated with corticosteroids, but most patients eventually become refractory to this treatment and toxicity is limiting. Growth factors still have a role in inherited cases, especially granulocyte colony-stimulating factor in congenital neutropenias. Novel therapies are warranted and thrombopoietin receptor agonists, leucine, quercetin, and novel gene therapy approaches may benefit inherited cases in the future.


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