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Multiple myeloma (MM) is a B-cell neoplasm that rounds 15% of all hematological malignancies. The typical clinical presentation of MM includes hypercalcemia, renal failure, anemia and bone lesion (CRAB). Effusions due to MM may occur due to secondary involvement of other organs and rarely are present at the initial diagnosis. Anaplastic myeloma (AMM) is rare morphological variant of multiple myeloma with predisposition of extramedullary affection. Herein, we describe a case of malignant plasmacytic ascites at disease onset of anaplastic multiple myeloma.
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Mieloma Múltiplo , Humanos , Mieloma Múltiplo/patologia , Mieloma Múltiplo/diagnóstico , Masculino , Ascite/patologia , Pessoa de Meia-Idade , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/diagnóstico , FemininoRESUMO
This study lays the groundwork for future lentivirus-mediated gene therapy in patients with Diamond Blackfan anemia (DBA) caused by mutations in ribosomal protein S19 (RPS19), showing evidence of a new safe and effective therapy. The data show that, unlike patients with Fanconi anemia (FA), the hematopoietic stem cell (HSC) reservoir of patients with DBA was not significantly reduced, suggesting that collection of these cells should not constitute a remarkable restriction for DBA gene therapy. Subsequently, 2 clinically applicable lentiviral vectors were developed. In the former lentiviral vector, PGK.CoRPS19 LV, a codon-optimized version of RPS19 was driven by the phosphoglycerate kinase promoter (PGK) already used in different gene therapy trials, including FA gene therapy. In the latter one, EF1α.CoRPS19 LV, RPS19 expression was driven by the elongation factor alpha short promoter, EF1α(s). Preclinical experiments showed that transduction of DBA patient CD34+ cells with the PGK.CoRPS19 LV restored erythroid differentiation, and demonstrated the long-term repopulating properties of corrected DBA CD34+ cells, providing evidence of improved erythroid maturation. Concomitantly, long-term restoration of ribosomal biogenesis was verified using a potentially novel method applicable to patients' blood cells, based on ribosomal RNA methylation analyses. Finally, in vivo safety studies and proviral insertion site analyses showed that lentivirus-mediated gene therapy was nontoxic.
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Anemia de Diamond-Blackfan , Terapia Genética , Vetores Genéticos , Células-Tronco Hematopoéticas , Lentivirus , Proteínas Ribossômicas , Anemia de Diamond-Blackfan/terapia , Anemia de Diamond-Blackfan/genética , Humanos , Terapia Genética/métodos , Lentivirus/genética , Proteínas Ribossômicas/genética , Vetores Genéticos/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Camundongos , Masculino , Feminino , Ribossomos/metabolismo , Ribossomos/genética , Regiões Promotoras Genéticas , Mutação , Transplante de Células-Tronco Hematopoéticas/métodosRESUMO
Clinical trials have shown that lentiviral-mediated gene therapy can ameliorate bone marrow failure (BMF) in nonconditioned Fanconi anemia (FA) patients resulting from the proliferative advantage of corrected FA hematopoietic stem and progenitor cells (HSPC). However, it is not yet known if gene therapy can revert affected molecular pathways in diseased HSPC. Single-cell RNA sequencing was performed in chimeric populations of corrected and uncorrected HSPC co-existing in the BM of gene therapy-treated FA patients. Our study demonstrates that gene therapy reverts the transcriptional signature of FA HSPC, which then resemble the transcriptional program of healthy donor HSPC. This includes a down-regulated expression of TGF-ß and p21, typically up-regulated in FA HSPC, and upregulation of DNA damage response and telomere maintenance pathways. Our results show for the first time the potential of gene therapy to rescue defects in the HSPC transcriptional program from patients with inherited diseases; in this case, in FA characterized by BMF and cancer predisposition.
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Anemia de Fanconi , Pancitopenia , Humanos , Anemia de Fanconi/genética , Anemia de Fanconi/terapia , Anemia de Fanconi/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Terapia Genética/métodos , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima , Pancitopenia/metabolismo , Transtornos da Insuficiência da Medula Óssea/metabolismoRESUMO
BACKGROUND: To assess visual quality and stabilization of refractive changes in corneal edema patients after cataract surgery, using visual acuity (VA) and contrast sensitivity measurements. METHODS: Sixty-one eyes were analysed, twenty-three with and thirty-eight without corneal edema. Uncorrected and corrected distance VA (UDVA and CDVA) were determined with an EDTRS chart, the contrast sensitivity function (CSF) under photopic and mesopic illumination conditions with a CVS-1000e chart, clinical refraction, and corneal topography. Measurements were taken preoperatively, 1-2 days, 1 and 3-months after surgery. Clinical refraction was converted to vector notation (M, J0, J45) and SPSS v26.0 was used for data analysis. RESULTS: An improvement of VA was observed through the postoperative period; changes between visits were significant for CDVA in both groups and for UDVA in the edema sample. Significant astigmatic changes (J0,J45) between visits were not observed, but M values showed a hyperopic tendency in the edema group and a myopic shift in the control group that did not change between visits, with statistically significant differences between groups. Controls had significantly better contrast sensitivity at high spatial frequencies. Under mesopic conditions, global contrast sensitivity losses were observed in the edema group, which improved between visits in the middle frequency range. CONCLUSION: Corneal edema patients had a significant reduction of CDVA, and frequency-selective sensitivity losses that evidence a visual quality loss. Clinical refraction may improve visual quality, but in edema patients these losses are related to corneal changes, which did not change at three months after surgery.
Assuntos
Catarata , Edema da Córnea , Córnea , Edema da Córnea/etiologia , Edema , Humanos , Refração OcularRESUMO
Fanconi anemia (FA) is the most prevalent inherited bone marrow failure (BMF) syndrome. Nevertheless, the pathophysiological mechanisms of BMF in FA have not been fully elucidated. Since FA cells are defective in DNA repair, we hypothesized that FA hematopoietic stem and progenitor cells (HSPCs) might express DNA damage-associated stress molecules such as natural killer group 2 member D ligands (NKG2D-Ls). These ligands could then interact with the activating NKG2D receptor expressed in cytotoxic NK or CD8+ T cells, which may result in progressive HSPC depletion. Our results indeed demonstrated upregulated levels of NKG2D-Ls in cultured FA fibroblasts and T cells, and these levels were further exacerbated by mitomycin C or formaldehyde. Notably, a high proportion of BM CD34+ HSPCs from patients with FA also expressed increased levels of NKG2D-Ls, which correlated inversely with the percentage of CD34+ cells in BM. Remarkably, the reduced clonogenic potential characteristic of FA HSPCs was improved by blocking NKG2D-NKG2D-L interactions. Moreover, the in vivo blockage of these interactions in a BMF FA mouse model ameliorated the anemia in these animals. Our study demonstrates the involvement of NKG2D-NKG2D-L interactions in FA HSPC functionality, suggesting an unexpected role of the immune system in the progressive BMF that is characteristic of FA.
Assuntos
Anemia de Fanconi , Animais , Antígenos CD34 , Anemia de Fanconi/genética , Células-Tronco Hematopoéticas , Ligantes , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Regulação para CimaRESUMO
Pyruvate kinase deficiency (PKD) is a rare autosomal recessive disorder caused by mutations in the PKLR gene. PKD is characterized by non-spherocytic hemolytic anemia of variable severity and may be fatal in some cases during early childhood. Although not considered the standard of care, allogeneic stem cell transplantation has been shown as a potentially curative treatment, limited by donor availability, toxicity, and incomplete engraftment. Preclinical studies were conducted to define conditions to enable consistent therapeutic reversal, which were based on our previous data on lentiviral gene therapy for PKD. Improvement of erythroid parameters was identified by the presence of 20%-30% healthy donor cells. A minimum vector copy number (VCN) of 0.2-0.3 was required to correct PKD when corrected cells were transplanted in a mouse model for PKD. Biodistribution and pharmacokinetics studies, with the aim of conducting a global gene therapy clinical trial for PKD patients (RP-L301-0119), demonstrated that genetically corrected cells do not confer additional side effects. Moreover, a clinically compatible transduction protocol with mobilized peripheral blood CD34+ cells was optimized, thus facilitating the efficient transduction on human cells capable of repopulating the hematopoiesis of immunodeficient mice. We established conditions for a curative lentiviral vector gene therapy protocol for PKD.
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Difficulties in the collection of hematopoietic stem and progenitor cells (HSPCs) from Fanconi anemia (FA) patients have limited the gene therapy in this disease. We have investigated (ClinicalTrials.gov, NCT02931071) the safety and efficacy of filgrastim and plerixafor for mobilization of HSPCs and collection by leukapheresis in FA patients. Nine of eleven enrolled patients mobilized beyond the threshold level of 5 CD34+ cells/µL required to initiate apheresis. A median of 21.8 CD34+ cells/µL was reached at the peak of mobilization. Significantly, the oldest patients (15 and 16 years old) were the only ones who did not reach that threshold. A median of 4.27 million CD34+ cells/kg was collected in 2 or 3 aphereses. These numbers were markedly decreased to 1.1 million CD34+ cells/kg after immunoselection, probably because of weak expression of the CD34 antigen. However, these numbers were sufficient to facilitate the engraftment of corrected HSPCs in non-conditioned patients. No procedure-associated serious adverse events were observed. Mobilization of CD34+ cells correlated with younger age, higher leukocyte counts and hemoglobin values, lower mean corpuscular volume, and higher proportion of CD34+ cells in bone marrow (BM). All these values offer crucial information for the enrollment of FA patients for gene therapy protocols.
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Fanconi anemia (FA) is characterized by chromosome fragility, bone marrow failure (BMF) and predisposition to cancer. As reverse genetic mosaicism has been described as "natural gene therapy" in patients with FA, we sought to evaluate the clinical course of a cohort of FA mosaic patients followed at referral centers in Spain over a 30-year period. This cohort includes patients with a majority of T cells without chromosomal aberrations in the DEB-chromosomal breakage test. Relative to non-mosaic FA patients, we observed a higher proportion of adult patients in the cohort of mosaics, with a later age of hematologic onset and a milder evolution of (BMF). Consequently, the requirement for hematopoietic stem cell transplant (HSCT) was also lower. Additional studies allowed us to identify a sub-cohort of mosaic FA patients in whom the reversion was present in bone marrow (BM) progenitor cells leading to multilineage mosaicism. These multilineage mosaic patients are older, have a lower percentage of aberrant cells, have more stable hematology and none of them developed leukemia or myelodysplastic syndrome when compared to non-mosaics. In conclusion, our data indicate that reverse mosaicism is a good prognostic factor in FA and is associated with more favorable long-term clinical outcomes.
Assuntos
Anemia de Fanconi/terapia , Terapia Genética/métodos , Adolescente , Adulto , Criança , Anemia de Fanconi/genética , Humanos , Masculino , Mosaicismo , Adulto JovemRESUMO
(1) Purpose: To assess the main corneal response differences between normal and subclinical keratoconus (SCKC) with a Corvis® ST device. (2) Material and Methods: We selected 183 eyes of normal patients, of a mean age of 33 ± 9 years and 16 eyes of patients with SCKC of a similar mean age. We measured best corrected visual acuity (BCVA) and corneal topography with a Pentacam HD device to select the SCKC group. Biomechanical measurements were performed using the Corvis® ST device. We carried out a non-parametric analysis of the data with SPSS software (Wilcoxon signed rank-test). (3) Results: We found statistically significant differences between the control and SCKC groups in some corneal biomechanical parameters: first and second applanation time (p = 0.05 and p = 0.02), maximum deformation amplitude (p = 0.016), highest concavity radius (p = 0.007), and second applanation length and corneal velocity ((p = 0.039 and p = 0.016). (4) Conclusions: Our results show that the use of normalised biomechanical parameters provided by noncontact tonometry, combined with a discriminant function theory, is a useful tool for detecting subclinical keratoconus.
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Inherited bone marrow failure syndromes (IBMFSs) are a group of congenital rare diseases characterized by bone marrow failure, congenital anomalies, high genetic heterogeneity, and predisposition to cancer. Appropriate treatment and cancer surveillance ideally depend on the identification of the mutated gene. A next-generation sequencing (NGS) panel of genes could be 1 initial genetic screening test to be carried out in a comprehensive study of IBMFSs, allowing molecular detection in affected patients. We designed 2 NGS panels of IBMFS genes: version 1 included 129 genes and version 2 involved 145 genes. The cohort included a total of 204 patients with suspected IBMFSs without molecular diagnosis. Capture-based targeted sequencing covered > 99% of the target regions of 145 genes, with more than 20 independent reads. No differences were seen between the 2 versions of the panel. The NGS tool allowed a total of 91 patients to be diagnosed, with an overall molecular diagnostic rate of 44%. Among the 167 patients with classified IBMFSs, 81 patients (48%) were diagnosed. Unclassified IBMFSs involved a total of 37 patients, of whom 9 patients (24%) were diagnosed. The preexisting diagnosis of 6 clinically classified patients (6%) was amended, implying a change of therapy for some of them. Our NGS IBMFS gene panel assay is a useful tool in the molecular diagnosis of IBMFSs and a reasonable option as the first tier genetic test in these disorders.
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Gene expression, the decoding of DNA information into accessible instructions for protein synthesis, is a complex process in which multiple steps, including transcription, mRNA processing and mRNA export, are regulated by different factors. One of the first steps in this process involves chemical and structural changes in chromatin to allow transcription. For such changes to occur, histone tail and DNA epigenetic modifications foster the binding of transcription factors to promoter regions. The SAGA coactivator complex plays a crucial role in this process by mediating histone acetylation through Gcn5, and histone deubiquitination through Ubp8 enzymes. However, most SAGA subunits interact physically with other proteins beyond the SAGA complex. These interactions could represent SAGA-independent functions or a mechanism to widen SAGA multifunctionality. Among the different mechanisms to perform more than one function, protein moonlighting defines unrelated molecular activities for the same polypeptide sequence. Unlike pleiotropy, where a single gene can affect different phenotypes, moonlighting necessarily involves separate functions of a protein at the molecular level. In this review we describe in detail some of the alternative physical interactions of several SAGA subunits. In some cases, the alternative role constitutes a clear moonlighting function, whereas in most of them the lack of molecular evidence means that we can only define these interactions as promiscuous that require further work to verify if these are moonlighting functions.
Assuntos
Eucariotos/enzimologia , Regulação da Expressão Gênica/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia , Subunidades Proteicas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transativadores/metabolismo , Acetilação , Eucariotos/genética , Histonas/metabolismo , Enzimas Multifuncionais/genética , Enzimas Multifuncionais/metabolismo , Subunidades Proteicas/química , Proteínas de Saccharomyces cerevisiae/química , Transativadores/química , Transcrição Gênica/fisiologia , Ubiquitinação/fisiologiaRESUMO
BACKGROUND: Histone H2B deubiquitination is performed by numerous deubiquitinases in eukaryotic cells including Ubp8, the catalytic subunit of the tetrameric deubiquitination module (DUBm: Ubp8; Sus1; Sgf11; Sgf73) of the Spt-Ada-Gcn5 acetyltransferase (SAGA). Ubp8 is linked to the rest of SAGA through Sgf73 and is activated by the adaptors Sus1 and Sgf11. It is unknown if DUBm/Ubp8 might also work in a SAGA-independent manner. RESULTS: Here we report that a tetrameric DUBm is assembled independently of the SAGA-CORE components SPT7, ADA1 and SPT20. In the absence of SPT7, i.e., independent of the SAGA complex, Ubp8 and Sus1 are poorly recruited to SAGA-dependent genes and to chromatin. Notably, cells lacking Spt7 or Ada1, but not Spt20, show lower levels of nuclear Ubp8 than wild-type cells, suggesting a possible role for SAGA-CORE subunits in Ubp8 localization. Last, deletion of SPT7 leads to defects in Ubp8 deubiquitinase activity in in vivo and in vitro assays. CONCLUSIONS: Collectively, our studies show that the DUBm tetrameric structure can form without a complete intact SAGA-CORE complex and that it includes full-length Sgf73. However, subunits of this SAGA-CORE influence DUBm association with chromatin, its localization and its activity.
Assuntos
Endopeptidases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Cromatina/metabolismo , Histonas/metabolismo , Ligação Proteica , Transporte Proteico , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , UbiquitinaçãoRESUMO
Meiosis is a specialized cell division that gives raise to four haploid gametes from a single diploid cell. During meiosis, homologous recombination is crucial to ensure genetic diversity and guarantee accurate chromosome segregation. Both the formation of programmed meiotic DNA double-strand breaks (DSBs) and their repair using homologous chromosomes are essential and highly regulated pathways. Similar to other processes that take place in the context of chromatin, histone posttranslational modifications (PTMs) constitute one of the major mechanisms to regulate meiotic recombination. In this review, we focus on specific PTMs occurring in histone tails as driving forces of different molecular events, including meiotic recombination and transcription. In particular, we concentrate on the influence of H3K4me3, H2BK123ub, and their corresponding molecular machineries that write, read, and erase these histone marks. The Spp1 subunit within the Complex of Proteins Associated with Set1 (COMPASS) is a critical regulator of H3K4me3-dependent meiotic DSB formation. On the other hand, the PAF1c (RNA polymerase II associated factor 1 complex) drives the ubiquitination of H2BK123 by Rad6-Bre1. We also discuss emerging evidence obtained by cryo-electron microscopy (EM) structure determination that has provided new insights into how the "cross-talk" between these two marks is accomplished.
Assuntos
Histonas/genética , Recombinação Homóloga/fisiologia , Meiose/fisiologia , Animais , Cromatina/metabolismo , Cromossomos/metabolismo , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , Endodesoxirribonucleases , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Recombinação Homóloga/genética , Humanos , Meiose/genética , Metilação , Processamento de Proteína Pós-Traducional/genética , Enzimas de Conjugação de Ubiquitina/genética , UbiquitinaçãoRESUMO
The alphaviruses Chikungunya (CHIKV), Mayaro (MAYV), Una (UNAV), and the flavivirus Zika (ZIKV) are emerging or re-emerging arboviruses which are responsible for frequent epidemic outbreaks. Despite the large impact of these arboviruses on health systems, there are no approved vaccines or treatments to fight these infections. As a consequence, there is an urgent need to discover new antiviral drugs. Natural products are a rich source of compounds with distinct biological activities, including antiviral properties. Thus, we aimed to explore the potential antiviral activity of Ginkgolic acid against the arboviruses CHIKV, MAYV, UNAV, and ZIKV. Viral progeny production in supernatants from cells treated or not treated with Ginkgolic acid was quantified by plaque-forming assay. Ginkgolic acid's direct virucidal activity against these arboviruses was also determined. Additionally, viral protein expression was assessed using Western blot and immunofluorescence. Our results reveal that Ginkgolic acid promotes a dose-dependent decrease in viral titers in all tested viruses. Moreover, the compound demonstrated strong virucidal activity. Finally, we found that viral protein expression was affected by treatment with this drug. Collectively, these findings suggest that Ginkgolic acid could have broader antiviral activity.
Assuntos
Alphavirus/efeitos dos fármacos , Antivirais/farmacologia , Vírus Chikungunya/efeitos dos fármacos , Salicilatos/farmacologia , Zika virus/efeitos dos fármacos , Animais , Células Cultivadas , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Células Vero , Ensaio de Placa Viral , Replicação Viral/efeitos dos fármacosRESUMO
The promising ability to genetically modify hematopoietic stem and progenitor cells by precise gene editing remains challenging due to their sensitivity to in vitro manipulations and poor efficiencies of homologous recombination. This study represents the first evidence of implementing a gene editing strategy in a murine safe harbor locus site that phenotypically corrects primary cells from a mouse model of Fanconi anemia A. By means of the co-delivery of transcription activator-like effector nucleases and a donor therapeutic FANCA template to the Mbs85 locus, we achieved efficient gene targeting (23%) in mFA-A fibroblasts. This resulted in the phenotypic correction of these cells, as revealed by the reduced sensitivity of these cells to mitomycin C. Moreover, robust evidence of targeted integration was observed in murine wild type and FA-A hematopoietic progenitor cells, reaching mean targeted integration values of 21% and 16% respectively, that were associated with the phenotypic correction of these cells. Overall, our results demonstrate the feasibility of implementing a therapeutic targeted integration strategy into the mMbs85 locus, ortholog to the well-validated hAAVS1, constituting the first study of gene editing in mHSC with TALEN, that sets the basis for the use of a new safe harbor locus in mice.
Assuntos
Anemia de Fanconi/genética , Edição de Genes/métodos , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/genética , Animais , Western Blotting , Instabilidade Cromossômica/genética , Feminino , Citometria de Fluxo , Células HEK293 , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Hibridização in Situ Fluorescente , Camundongos Endogâmicos C57BL , GravidezRESUMO
Gene expression is a biological process regulated at different molecular levels, including chromatin accessibility, transcription, and RNA maturation and transport. In addition, these regulatory mechanisms have strong links with cellular metabolism. Here we present a multi-omics dataset that captures different aspects of this multi-layered process in yeast. We obtained RNA-seq, metabolomics, and H4K12ac ChIP-seq data for wild-type and mip6Δ strains during a heat-shock time course. Mip6 is an RNA-binding protein that contributes to RNA export during environmental stress and is informative of the contribution of post-transcriptional regulation to control cellular adaptations to environmental changes. The experiment was performed in quadruplicate, and the different omics measurements were obtained from the same biological samples, which facilitates the integration and analysis of data using covariance-based methods. We validate our dataset by showing that ChIP-seq, RNA-seq and metabolomics signals recapitulate existing knowledge about the response of ribosomal genes and the contribution of trehalose metabolism to heat stress. Raw data, processed data and preprocessing scripts are made available.
Assuntos
Regulação Fúngica da Expressão Gênica , Resposta ao Choque Térmico , Proteínas de Ligação a RNA/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Imunoprecipitação da Cromatina , Metabolômica , RNA , RNA-Seq , Trealose/metabolismoRESUMO
Fanconi anemia (FA) is a DNA repair disorder resulting from mutations in genes encoding for FA DNA repair complex components and is characterized by variable congenital abnormalities, bone marrow failure (BMF), and high incidences of malignancies. FA mosaicism arises from reversion or other compensatory mutations in hematopoietic cells and may be associated with BMF reversal and decreased blood cell sensitivity to DNA-damaging agents (clastogens); this sensitivity is a phenotypic and diagnostic hallmark of FA. Uncertainty regarding the clinical significance of FA mosaicism persists; in some cases, patients have survived multiple decades without BMF or hematologic malignancy, and in others hematologic failure occurred despite the presence of clastogen-resistant cell populations. Assessment of mosaicism is further complicated because clinical evaluation is frequently based on clastogen resistance in lymphocytes, which may arise from reversion events both in lymphoid-specific lineages and in more pluripotent hematopoietic stem/progenitor cells (HSPCs). In this review, we describe diagnostic methods and outcomes in published mosaicism series, including the substantial intervals (1-6 years) over which blood counts normalized, and the relatively favorable clinical course in cases where clastogen resistance was demonstrated in bone marrow progenitors. We also analyzed published FA mosaic cases with emphasis on long-term clinical outcomes when blood count normalization was identified. Blood count normalization in FA mosaicism likely arises from reversion events in long-term primitive HSPCs and is associated with low incidences of BMF or hematologic malignancy. These observations have ramifications for current investigational therapeutic programs in FA intended to enable gene correction in long-term repopulating HSPCs.
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Células da Medula Óssea/metabolismo , Anemia de Fanconi , Neoplasias Hematológicas , Células-Tronco Hematopoéticas/metabolismo , Mosaicismo , Células da Medula Óssea/patologia , Anemia de Fanconi/sangue , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/genética , Anemia de Fanconi/terapia , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/terapia , HumanosRESUMO
Hematopoietic gene therapy has markedly progressed during the last 15 years both in terms of safety and efficacy. While a number of serious adverse events (SAE) were initially generated as a consequence of genotoxic insertions of gamma-retroviral vectors in the cell genome, no SAEs and excellent outcomes have been reported in patients infused with autologous hematopoietic stem cells (HSCs) transduced with self-inactivated lentiviral and gammaretroviral vectors. Advances in the field of HSC gene therapy have extended the number of monogenic diseases that can be treated with these approaches. Nowadays, evidence of clinical efficacy has been shown not only in primary immunodeficiencies, but also in other hematopoietic diseases, including beta-thalassemia and sickle cell anemia. In addition to the rapid progression of non-targeted gene therapies in the clinic, new approaches based on gene editing have been developed thanks to the discovery of designed nucleases and improved non-integrative vectors, which have markedly increased the efficacy and specificity of gene targeting to levels compatible with its clinical application. Based on advances achieved in the field of gene therapy, it can be envisaged that these therapies will soon be part of the therapeutic approaches used to treat life-threatening diseases of the hematopoietic system.
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Anemia Falciforme/terapia , Terapia Genética/tendências , Doenças Hematológicas/terapia , Talassemia beta/terapia , Anemia Falciforme/sangue , Células Sanguíneas/patologia , Células Sanguíneas/transplante , Vetores Genéticos/efeitos adversos , Doenças Hematológicas/sangue , Doenças Hematológicas/patologia , Transplante de Células-Tronco Hematopoéticas/tendências , Células-Tronco Hematopoéticas/citologia , Humanos , Talassemia beta/sangueRESUMO
RNA-binding proteins (RBPs) participate in all steps of gene expression, underscoring their potential as regulators of RNA homeostasis. We structurally and functionally characterize Mip6, a four-RNA recognition motif (RRM)-containing RBP, as a functional and physical interactor of the export factor Mex67. Mip6-RRM4 directly interacts with the ubiquitin-associated (UBA) domain of Mex67 through a loop containing tryptophan 442. Mip6 shuttles between the nucleus and the cytoplasm in a Mex67-dependent manner and concentrates in cytoplasmic foci under stress. Photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation experiments show preferential binding of Mip6 to mRNAs regulated by the stress-response Msn2/4 transcription factors. Consistent with this binding, MIP6 deletion affects their export and expression levels. Additionally, Mip6 interacts physically and/or functionally with proteins with a role in mRNA metabolism and transcription such as Rrp6, Xrn1, Sgf73, and Rpb1. These results reveal a novel role for Mip6 in the homeostasis of Msn2/4-dependent transcripts through its direct interaction with the Mex67 UBA domain.
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Núcleo Celular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transporte Ativo do Núcleo Celular , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas de Transporte Nucleocitoplasmático/química , Proteínas de Transporte Nucleocitoplasmático/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Fanconi anemia (FA) is a DNA repair syndrome generated by mutations in any of the 22 FA genes discovered to date1,2. Mutations in FANCA account for more than 60% of FA cases worldwide3,4. Clinically, FA is associated with congenital abnormalities and cancer predisposition. However, bone marrow failure is the primary pathological feature of FA that becomes evident in 70-80% of patients with FA during the first decade of life5,6. In this clinical study (ClinicalTrials.gov, NCT03157804 ; European Clinical Trials Database, 2011-006100-12), we demonstrate that lentiviral-mediated hematopoietic gene therapy reproducibly confers engraftment and proliferation advantages of gene-corrected hematopoietic stem cells (HSCs) in non-conditioned patients with FA subtype A. Insertion-site analyses revealed the multipotent nature of corrected HSCs and showed that the repopulation advantage of these cells was not due to genotoxic integrations of the therapeutic provirus. Phenotypic correction of blood and bone marrow cells was shown by the acquired resistance of hematopoietic progenitors and T lymphocytes to DNA cross-linking agents. Additionally, an arrest of bone marrow failure progression was observed in patients with the highest levels of gene marking. The progressive engraftment of corrected HSCs in non-conditioned patients with FA supports that gene therapy should constitute an innovative low-toxicity therapeutic option for this life-threatening disorder.