RESUMEN
BACKGROUND: Developing a prognostic model for lung adenocarcinoma (LUAD) that utilizes m6A/m5C/m1A genes holds immense importance in providing precise prognosis predictions for individuals. METHODS: This study mined m6A/m5C/m1A-related differential genes in LUAD based on public databases, identified LUAD tumor subtypes based on these genes, and further built a risk prognostic model grounded in differential genes between subtypes. The immune status between high- and low-risk groups was investigated, and the distribution of feature genes in tumor immune cells was analyzed using single-cell analysis. Based on the expression levels of feature genes, a projection of chemotherapeutic and targeted drugs was made for individuals identified as high-risk. Ultimately, cell experiments were further verified. RESULTS: The 6-gene risk prognosis model based on differential genes between tumor subtypes had good predictive performance. Individuals classified as low-risk exhibited a higher (P < 0.05) abundance of infiltrating immune cells. Feature genes were mainly distributed in tumor immune cells like CD4+T cells, CD8+T cells, and regulatory T cells. Four drugs with relatively low IC50 values were found in the high-risk group: Elesclomol, Pyrimethamine, Saracatinib, and Temsirolimus. In addition, four drugs with significant positive correlation (P < 0.001) between IC50 values and feature gene expression were found, including Alectinib, Estramustine, Brigatinib, and Elesclomol. The low expression of key gene NTSR1 reduced the IC50 value of irinotecan. CONCLUSION: Based on the m6A/m5C/m1A-related genes in LUAD, LUAD patients were divided into 2 subtypes, and a m6A/m5C/m1A-related LUAD prognostic model was constructed to provide a reference for the prognosis prediction of LUAD.
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Adenina/análogos & derivados , Adenocarcinoma del Pulmón , Hidrazinas , Neoplasias Pulmonares , Humanos , Pronóstico , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Microambiente TumoralRESUMEN
Transmembrane channels and pores have key roles in fundamental biological processes1 and in biotechnological applications such as DNA nanopore sequencing2-4, resulting in considerable interest in the design of pore-containing proteins. Synthetic amphiphilic peptides have been found to form ion channels5,6, and there have been recent advances in de novo membrane protein design7,8 and in redesigning naturally occurring channel-containing proteins9,10. However, the de novo design of stable, well-defined transmembrane protein pores that are capable of conducting ions selectively or are large enough to enable the passage of small-molecule fluorophores remains an outstanding challenge11,12. Here we report the computational design of protein pores formed by two concentric rings of α-helices that are stable and monodisperse in both their water-soluble and their transmembrane forms. Crystal structures of the water-soluble forms of a 12-helical pore and a 16-helical pore closely match the computational design models. Patch-clamp electrophysiology experiments show that, when expressed in insect cells, the transmembrane form of the 12-helix pore enables the passage of ions across the membrane with high selectivity for potassium over sodium; ion passage is blocked by specific chemical modification at the pore entrance. When incorporated into liposomes using in vitro protein synthesis, the transmembrane form of the 16-helix pore-but not the 12-helix pore-enables the passage of biotinylated Alexa Fluor 488. A cryo-electron microscopy structure of the 16-helix transmembrane pore closely matches the design model. The ability to produce structurally and functionally well-defined transmembrane pores opens the door to the creation of designer channels and pores for a wide variety of applications.
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Simulación por Computador , Genes Sintéticos/genética , Canales Iónicos/química , Canales Iónicos/genética , Modelos Moleculares , Biología Sintética , Línea Celular , Microscopía por Crioelectrón , Cristalografía por Rayos X , Conductividad Eléctrica , Escherichia coli/genética , Escherichia coli/metabolismo , Hidrazinas , Canales Iónicos/metabolismo , Transporte Iónico , Liposomas/metabolismo , Técnicas de Placa-Clamp , Porinas/química , Porinas/genética , Porinas/metabolismo , Ingeniería de Proteínas , Estructura Secundaria de Proteína , Solubilidad , Agua/químicaRESUMEN
Recent studies have uncovered the therapeutic potential of elesclomol (ES), a copper-ionophore, for copper deficiency disorders. However, we currently do not understand the mechanism by which copper brought into cells as ES-Cu(II) is released and delivered to cuproenzymes present in different subcellular compartments. Here, we have utilized a combination of genetic, biochemical, and cell-biological approaches to demonstrate that intracellular release of copper from ES occurs inside and outside of mitochondria. The mitochondrial matrix reductase, FDX1, catalyzes the reduction of ES-Cu(II) to Cu(I), releasing it into mitochondria where it is bioavailable for the metalation of mitochondrial cuproenzyme- cytochrome c oxidase. Consistently, ES fails to rescue cytochrome c oxidase abundance and activity in copper-deficient cells lacking FDX1. In the absence of FDX1, the ES-dependent increase in cellular copper is attenuated but not abolished. Thus, ES-mediated copper delivery to nonmitochondrial cuproproteins continues even in the absence of FDX1, suggesting alternate mechanism(s) of copper release. Importantly, we demonstrate that this mechanism of copper transport by ES is distinct from other clinically used copper-transporting drugs. Our study uncovers a unique mode of intracellular copper delivery by ES and may further aid in repurposing this anticancer drug for copper deficiency disorders.
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Cobre , Complejo IV de Transporte de Electrones , Hidrazinas , Ionóforos , Ferredoxinas/metabolismoRESUMEN
Magnetic fields are being used for detailed anatomical and functional examination of the human brain. In addition, evidence for their efficacy in treatment of brain dysfunctions is accumulating. Transcranial static magnetic field stimulation (tSMS) is a recently developed technique for noninvasively modifying brain functions. In tSMS, a strong and small magnet when placed over the skull can temporarily suppress brain functions. Its modulatory effects persist beyond the time of stimulation. However, the neurophysiological mechanisms underlying tSMS-induced plasticity remain unclear. Here, using acute motor cortical slice preparation obtained from male C57BL/6N mice, we show that tSMS alters the intrinsic electrical properties of neurons by altering the activity of chloride (Cl-) channels in neurons. Exposure of mouse pyramidal neurons to a static magnetic field (SMF) at a strength similar to human tSMS temporarily decreased their excitability and induced transient neuronal swelling. The effects of SMF were blocked by DIDS and GlyH-101, but not by NPPB, consistent with the pharmacological profile of SLC26A11, a transporter protein with Cl- channel activity. Whole-cell voltage-clamp recordings of the GlyH-101-sensitive Cl- current component showed significant enhancement of the component at both subthreshold and depolarized membrane potentials after SMF application, resulting in shunting inhibition and reduced repetitive action potential (AP) firing at the respective potentials. Thus, this study provides the first neurophysiological evidence for the inhibitory effect of tSMS on neuronal activity and advances our mechanistic understanding of noninvasive human neuromodulation.
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Cloruros , Glicina/análogos & derivados , Hidrazinas , Campos Magnéticos , Masculino , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Estimulación Magnética Transcraneal/métodosRESUMEN
BACKGROUND: A single-group, phase 1-2 study indicated that eltrombopag improved the efficacy of standard immunosuppressive therapy that entailed horse antithymocyte globulin (ATG) plus cyclosporine in patients with severe aplastic anemia. METHODS: In this prospective, investigator-led, open-label, multicenter, randomized, phase 3 trial, we compared the efficacy and safety of horse ATG plus cyclosporine with or without eltrombopag as front-line therapy in previously untreated patients with severe aplastic anemia. The primary end point was a hematologic complete response at 3 months. RESULTS: Patients were assigned to receive immunosuppressive therapy (Group A, 101 patients) or immunosuppressive therapy plus eltrombopag (Group B, 96 patients). The percentage of patients who had a complete response at 3 months was 10% in Group A and 22% in Group B (odds ratio, 3.2; 95% confidence interval [CI], 1.3 to 7.8; P = 0.01). At 6 months, the overall response rate (the percentage of patients who had a complete or partial response) was 41% in Group A and 68% in Group B. The median times to the first response were 8.8 months (Group A) and 3.0 months (Group B). The incidence of severe adverse events was similar in the two groups. With a median follow-up of 24 months, a karyotypic abnormality that was classified as myelodysplastic syndrome developed in 1 patient (Group A) and 2 patients (Group B); event-free survival was 34% and 46%, respectively. Somatic mutations were detected in 29% (Group A) and 31% (Group Β) of the patients at baseline; these percentages increased to 66% and 55%, respectively, at 6 months, without affecting the hematologic response and 2-year outcome. CONCLUSIONS: The addition of eltrombopag to standard immunosuppressive therapy improved the rate, rapidity, and strength of hematologic response among previously untreated patients with severe aplastic anemia, without additional toxic effects. (Funded by Novartis and others; RACE ClinicalTrials.gov number, NCT02099747; EudraCT number, 2014-000363-40.).
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Anemia Aplásica/terapia , Suero Antilinfocítico/uso terapéutico , Benzoatos/uso terapéutico , Ciclosporina/uso terapéutico , Hidrazinas/uso terapéutico , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Pirazoles/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anemia Aplásica/tratamiento farmacológico , Anemia Aplásica/genética , Suero Antilinfocítico/efectos adversos , Benzoatos/efectos adversos , Ciclosporina/efectos adversos , Quimioterapia Combinada , Femenino , Humanos , Hidrazinas/efectos adversos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Estudios Prospectivos , Pirazoles/efectos adversos , Receptores de Trombopoyetina/agonistas , Inducción de Remisión , Adulto JovenRESUMEN
BACKGROUND & AIMS: Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer. METHODS: A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells. RESULTS: The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells. CONCLUSIONS: Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.
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Proteínas Adaptadoras Transductoras de Señales , Senescencia Celular , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Proteína Exportina 1 , Carioferinas , Neoplasias Hepáticas , Inhibidores de Proteínas Quinasas , Receptores Citoplasmáticos y Nucleares , Ubiquitina-Proteína Ligasas , Humanos , Senescencia Celular/efectos de los fármacos , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/metabolismo , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Carioferinas/antagonistas & inhibidores , Carioferinas/metabolismo , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Receptores Citoplasmáticos y Nucleares/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Animales , Proteínas de Unión a Retinoblastoma/metabolismo , Proteínas de Unión a Retinoblastoma/genética , Sinergismo Farmacológico , Senoterapéuticos/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Transducción de Señal/efectos de los fármacos , Proteolisis/efectos de los fármacos , Hidrazinas/farmacología , Hidrazinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Células Hep G2 , Ratones , Piperazinas , Piridinas , TriazolesRESUMEN
Sustained response off treatment (SROT) after thrombopoietin receptor agonist (TPO-RA) discontinuation has been reported in immune thrombocytopenia (ITP). This prospective multicenter interventional study enrolled adults with persistent or chronic primary ITP and complete response (CR) on TPO-RAs. The primary end point was the proportion of patients achieving SROT (platelet count >30 × 109/L and no bleeding) at week 24 (W24) with no other ITP-specific medications. Secondary end points included the proportion of sustained CR off-treatment (SCROT, platelet count >100 × 109/L and no bleeding) and SROT at W52, bleeding events, and pattern of response to a new course of TPO-RAs. We included 48 patients with a median age of 58.5 years; 30 of 48 had chronic ITP at TPO-RA initiation. In the intention-to-treat analysis, 27 of 48 achieved SROT, 15 of 48 achieved SCROT at W24; 25 of 48 achieved SROT, and 14 of 48 achieved SCROT at W52. No severe bleeding episode occurred in patients who relapsed. Among patients rechallenged with TPO-RA, 11 of 12 achieved CR. We found no significant clinical predictors of SROT at W24. Single-cell RNA sequencing revealed enrichment of a tumor necrosis factor α signaling via NF-κB signature in CD8+ T cells of patients with no sustained response after TPO-RA discontinuation, which was further confirmed by a significant overexpression of CD69 on CD8+ T cells at baseline in these patients as compared with those achieving SCROT/SROT. Our results strongly support a strategy based on progressive tapering and discontinuation of TPO-RAs for patients with chronic ITP who achieved a stable CR on treatment. This trial was registered at www.clinicaltrials.gov as #NCT03119974.
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Púrpura Trombocitopénica Idiopática , Trombocitopenia , Adulto , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Recuento de Plaquetas , Trombocitopenia/tratamiento farmacológico , Autoinmunidad , Trombopoyetina/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Receptores Fc/uso terapéutico , Hidrazinas/uso terapéuticoRESUMEN
Carbon-hydrogen (C-H) and carbon-carbon (C-C) bonds are the main constituents of organic matter. Recent advances in C-H functionalization technology have vastly expanded our toolbox for organic synthesis1. By contrast, C-C activation methods that enable editing of the molecular skeleton remain limited2-7. Several methods have been proposed for catalytic C-C activation, particularly with ketone substrates, that are typically promoted by using either ring-strain release as a thermodynamic driving force4,6 or directing groups5,7 to control the reaction outcome. Although effective, these strategies require substrates that contain highly strained ketones or a preinstalled directing group, or are limited to more specialist substrate classes5. Here we report a general C-C activation mode driven by aromatization of a pre-aromatic intermediate formed in situ. This reaction is suitable for various ketone substrates, is catalysed by an iridium/phosphine combination and is promoted by a hydrazine reagent and 1,3-dienes. Specifically, the acyl group is removed from the ketone and transformed to a pyrazole, and the resulting alkyl fragment undergoes various transformations. These include the deacetylation of methyl ketones, carbenoid-free formal homologation of aliphatic linear ketones and deconstructive pyrazole synthesis from cyclic ketones. Given that ketones are prevalent in feedstock chemicals, natural products and pharmaceuticals, these transformations could offer strategic bond disconnections in the synthesis of complex bioactive molecules.
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Carbono/química , Cetonas/química , Acilación , Hidrazinas/química , Iridio/química , Fosfinas/química , Pirazoles/síntesis química , Pirazoles/químicaRESUMEN
Soluble guanylate cyclase (sGC) is the primary sensor of nitric oxide. It has a central role in nitric oxide signalling and has been implicated in many essential physiological processes and disease conditions. The binding of nitric oxide boosts the enzymatic activity of sGC. However, the mechanism by which nitric oxide activates the enzyme is unclear. Here we report the cryo-electron microscopy structures of the human sGCα1ß1 heterodimer in different functional states. These structures revealed that the transducer module bridges the nitric oxide sensor module and the catalytic module. Binding of nitric oxide to the ß1 haem-nitric oxide and oxygen binding (H-NOX) domain triggers the structural rearrangement of the sensor module and a conformational switch of the transducer module from bending to straightening. The resulting movement of the N termini of the catalytic domains drives structural changes within the catalytic module, which in turn boost the enzymatic activity of sGC.
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Microscopía por Crioelectrón , Guanilil Ciclasa Soluble/metabolismo , Guanilil Ciclasa Soluble/ultraestructura , Animales , Disulfuros/química , Disulfuros/metabolismo , Drosophila melanogaster , Activación Enzimática , Células HEK293 , Hemo/metabolismo , Humanos , Hidrazinas/farmacología , Ratones , Modelos Moleculares , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/metabolismo , Oxígeno/metabolismo , Dominios Proteicos , Multimerización de Proteína , Guanilil Ciclasa Soluble/química , Guanilil Ciclasa Soluble/genéticaRESUMEN
Chromosomal region maintenance 1 (CRM1 also known as Xpo1 and exportin-1) is the receptor for the nuclear export controlling the intracellular localization and function of many cellular and viral proteins that play a crucial role in viral infections and cancer. The inhibition of CRM1 has emerged as a promising therapeutic approach to interfere with the lifecycle of many viruses, for the treatment of cancer, and to overcome therapy resistance. Recently, selinexor has been approved as the first CRM1 inhibitor for the treatment of multiple myeloma, providing proof of concept for this therapeutic option with a new mode of action. However, selinexor is associated with dose-limiting toxicity and hence, the discovery of alternative small molecule leads that could be developed as less toxic anticancer and antiviral therapeutics will have a significant impact in the clinic. Here, we report a CRM1 inhibitor discovery platform. The development of this platform includes reporter cell lines that monitor CRM1 activity by using red fluorescent protein or green fluorescent protein-labeled HIV-1 Rev protein with a strong heterologous nuclear export signal. Simultaneously, the intracellular localization of other proteins, to be interrogated for their capacity to undergo CRM1-mediated export, can be followed by co-culturing stable cell lines expressing fluorescent fusion proteins. We used this platform to interrogate the mode of nuclear export of several proteins, including PDK1, p110α, STAT5A, FOXO1, 3, 4 and TRIB2, and to screen a compound collection. We show that while p110α partially relies on CRM1-dependent nuclear export, TRIB2 is exported from the nucleus in a CRM1-independent manner. Compound screening revealed the striking activity of an organoselenium compound on the CRM1 nuclear export receptor.
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VIH-1 , Transporte Activo de Núcleo Celular , VIH-1/metabolismo , Carioferinas/metabolismo , Triazoles/metabolismo , Hidrazinas/farmacología , Hidrazinas/metabolismo , Núcleo Celular/metabolismoRESUMEN
In rodents and humans, the major cellular events at spermatogenesis include self-renewal of spermatogonial stem cells and undifferentiated spermatogonia via mitosis, commitment of spermatogonia to differentiation and transformation to spermatocytes, meiosis, spermiogenesis, and the release of spermatozoa at spermiation. While details of the morphological changes during these cellular events have been delineated, knowledge gap exists between the morphological changes in the seminiferous epithelium and the underlying molecular mechanism(s) that regulate these cellular events. Even though many of the regulatory proteins and biomolecules that modulate spermatogenesis are known based on studies using genetic models, the underlying regulatory mechanism(s), in particular signaling pathways/proteins, remain unexplored since much of the information regarding the signaling regulation is unknown. Studies in the past decade, however, have unequivocally demonstrated that the testis is using several signaling proteins and/or pathways to regulate multiple cellular events to modulate spermatogenesis. These include mTORC1/rpS6/Akt1/2 and p-FAK-Y407. While selective inhibitors and/or agonists and antagonists are available to examine some of these signaling proteins, their use have limitations due to their specificities and also potential systemic cytotoxicity. On the other hand, the use of genetic models has had profound implications for our understanding of the molecular regulation of spermatogenesis, and these knockout (null) models have also revealed the factors that are critical for spermatogenesis. Nonetheless, additional studies using in vitro and in vivo models are necessary to unravel the signaling pathways involved in regulating seminiferous epithelial cycle. Emerging data from studies, such as the use of the adjudin pharmaceutical/toxicant model, have illustrated that this non-hormonal male contraceptive drug is utilizing specific signaling pathways/proteins to induce specific defects in spermatogenesis, yielding mechanistic insights on the regulation of spermatogenesis. We sought to review these recent data in this article, highlighting an interesting approach that can be considered for future studies.
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Hidrazinas/uso terapéutico , Indazoles/uso terapéutico , Diana Mecanicista del Complejo 1 de la Rapamicina/inmunología , Espermatogénesis/inmunología , Animales , Humanos , Hidrazinas/farmacología , Indazoles/farmacología , Masculino , Transducción de SeñalRESUMEN
Structural motifs containing nitrogen-nitrogen (N-N) bonds are prevalent in a large number of clinical drugs and bioactive natural products. Hydrazine (N2H4) serves as a widely utilized building block for the preparation of these N-N-containing molecules in organic synthesis. Despite its common use in chemical processes, no enzyme has been identified to catalyze the incorporation of free hydrazine in natural product biosynthesis. Here, we report that a hydrazine transferase catalyzes the condensation of N2H4 and an aromatic polyketide pathway intermediate, leading to the formation of a rare N-aminolactam pharmacophore in the biosynthesis of broad-spectrum antibiotic albofungin. These results expand the current knowledge on the biosynthetic mechanism for natural products with N-N units and should facilitate future development of biocatalysts for the production of N-N-containing chemicals.
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Hidrazinas , Hidrazinas/química , Hidrazinas/metabolismo , Antibacterianos/química , Antibacterianos/biosíntesis , Antibacterianos/farmacología , Streptomyces/enzimología , Streptomyces/metabolismo , Lactamas/química , Lactamas/metabolismo , FarmacóforoRESUMEN
The rich history surrounding Diamond-Blackfan anaemia (DBA), originally described in 1938 as congenital hypoplastic anaemia2 reflects the evolution of paediatric haematology. In their paper, the authors1 present the results of a clinical trial using the thrombopoietin-mimetic agent eltrombopag to treat red cell failure in DBA. A low response rate belies the importance of this work. Commentary on: Duncan et al. Treatment of refractory/relapsed Diamond-Blackfan anaemia with eltrombopag. Br J Haematol 2024;204:2077-2085.
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Anemia de Diamond-Blackfan , Benzoatos , Hidrazinas , Pirazoles , Anemia de Diamond-Blackfan/tratamiento farmacológico , Humanos , Pirazoles/uso terapéutico , Benzoatos/uso terapéutico , Hidrazinas/uso terapéuticoRESUMEN
Diamond-Blackfan anaemia (DBA) is a rare, inherited bone marrow failure syndrome with a ribosomal defect causing slowed globin chain production with normal haem synthesis, causing an overabundance of reactive iron/haem and erythroid-specific cellular toxicity. Eltrombopag, a non-peptide thrombopoietin receptor agonist, is a potent intracellular iron chelator and induced a robust durable response in an RPS19-mutated DBA patient on another trial. We hypothesized eltrombopag would improve RBC production in DBA patients. We conducted a single-centre, single-arm pilot study (NCT04269889) assessing safety and erythroid response of 6 months of daily, fixed-dose eltrombopag for DBA patients. Fifteen transfusion-dependent (every 3-5 weeks) patients (median age 18 [range 2-56]) were treated. One responder had sustained haemoglobin improvement and >50% reduction in RBC transfusion frequency. Of note, 7/15 (41%) patients required dose reductions or sustained discontinuation of eltrombopag due to asymptomatic thrombocytosis. Despite the low response rate, eltrombopag has now improved erythropoiesis in several patients with DBA with a favourable safety profile. Dosing restrictions due to thrombocytosis may cause insufficient iron chelation to decrease haem production and improve anaemia in most patients. Future work will focus on erythropoiesis dynamics in patients and use of haem synthesis inhibitors without an impact on other haematopoietic lineages.
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Anemia de Diamond-Blackfan , Benzoatos , Hidrazinas , Pirazoles , Humanos , Anemia de Diamond-Blackfan/tratamiento farmacológico , Pirazoles/uso terapéutico , Hidrazinas/uso terapéutico , Hidrazinas/administración & dosificación , Hidrazinas/efectos adversos , Benzoatos/uso terapéutico , Benzoatos/administración & dosificación , Benzoatos/efectos adversos , Adulto , Masculino , Femenino , Niño , Adolescente , Persona de Mediana Edad , Adulto Joven , Preescolar , Proyectos Piloto , Resultado del Tratamiento , Receptores de Trombopoyetina/agonistas , Recurrencia , Eritropoyesis/efectos de los fármacosRESUMEN
Few studies have reported the real-world use of both romiplostim and eltrombopag in immune thrombocytopenia (ITP). TRAIT was a retrospective observational study aimed to evaluate the platelet responses and adverse effects associated with the use of these thrombopoietin receptor agonists (TPO-RAs) in adult patients with ITP in the United Kingdom. Of 267 patients (median age at diagnosis, 48 years) with ITP (primary ITP [n = 218], secondary ITP [n = 49]) included in the study, 112 (42%) received eltrombopag and 155 (58%) received romiplostim as the first prescribed TPO-RA. A platelet count ≥30 × 109/L was achieved in 89% of patients with the first TPO-RA treatments, while 68% achieved a platelet count ≥100 × 109/L. Treatment-free response (TFR; platelet count ≥30 × 109/L, 3 months after discontinuing treatment) was achieved by 18% of the total patients. Overall, 61 patients (23%) switched TPO-RAs, most of whom achieved platelet counts ≥30 × 109/L with the second TPO-RA (23/25 who switched from eltrombopag to romiplostim [92%]; 28/36 who switched from romiplostim to eltrombopag [78%]). TFR was associated with secondary ITP, early TPO-RA initiation after diagnosis, the presence of comorbidity and no prior splenectomy or treatment with steroids or mycophenolate mofetil. Both TPO-RAs had similar efficacy and safety profiles to those reported in clinical studies.
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Benzoatos , Hidrazinas , Púrpura Trombocitopénica Idiopática , Pirazoles , Receptores Fc , Receptores de Trombopoyetina , Proteínas Recombinantes de Fusión , Trombopoyetina , Humanos , Receptores de Trombopoyetina/agonistas , Proteínas Recombinantes de Fusión/uso terapéutico , Proteínas Recombinantes de Fusión/efectos adversos , Proteínas Recombinantes de Fusión/administración & dosificación , Persona de Mediana Edad , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Benzoatos/uso terapéutico , Benzoatos/efectos adversos , Masculino , Femenino , Pirazoles/uso terapéutico , Pirazoles/efectos adversos , Trombopoyetina/uso terapéutico , Trombopoyetina/efectos adversos , Hidrazinas/uso terapéutico , Hidrazinas/efectos adversos , Receptores Fc/uso terapéutico , Adulto , Reino Unido , Estudios Retrospectivos , Anciano , Recuento de Plaquetas , Resultado del Tratamiento , Anciano de 80 o más Años , Adulto Joven , AdolescenteRESUMEN
We have previously confirmed the efficacy and safety of eltrombopag (ELT) in children with chronic immune thrombocytopenia (cITP). However, data on both long-term exposure and early use of TPO-RAs are lacking, so further 'field-practice' evidence on treatment is required. Here, we report the long-term follow-up results (between September 2018 and June 2023) of our previous study. The main objective of this study was to retrospectively review our large institutional experience with ITP patients previously enrolled in our paediatric cITP study. We had more than 3 years of follow-up by June 2023 for treatment patterns and outcomes. A total of 65 patients (28 males) were enrolled, with a median age at ELT initiation of 6.34 (range 1.65, 14.13) years and a follow-up of 47.07 (36.00, 57.00) months, with 40.36 (10.53, 56.83) months of ELT therapy at the time of analysis. In total, 29.23% (19/65) of patients discontinued ELT due to stable response, and 18.46% (12/65) of patients switched to other ITP therapies due to loss of response (LOR) after 19.13 (14.53, 26.37) months. Of the 19 patients who discontinued ELT due to a stable response, 24.62% (16/65) achieved a 12 m sustained response off-treatment (SRoT); the last recorded platelet count ranged from 56 to 166 × 109 /L (median 107 × 109/L); and 4.62% (3/65) patients relapsed at 5, 6 and 9 months after discontinuation. Of the 12 patients who LOR to ELT after 19.13 (14.53, 26.37) months of therapy, four switched to avatrombopag, three switched to hetrombopag, two switched to traditional Chinese medicine (TCM), one underwent splenectomy and two received additional prednisolone under ELT treatment. Thirty-four patients who tapered and maintained a durable response. The patients with LOR and the patients with tapering were compared; the platelet count at the start of ELT is lower, and the time to response is longer in the patients with LOR. The platelet count at the start of ELT and the time to response may be the predictive factors for LOR during ELT treatment. We report more than 3 years of long-term clinical data on children with cITP using ELT. These data do not raise any new safety concerns regarding the long-term use of ELT in children with cITP.
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Púrpura Trombocitopénica Idiopática , Pirazoles , Masculino , Humanos , Niño , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento , Receptores de Trombopoyetina , Hidrazinas/uso terapéutico , Benzoatos/uso terapéutico , ChinaRESUMEN
The coronavirus disease 2019 (COVID-19) pandemic has a significant impact on the immune system. This is the first and largest study on pre-existing immune thrombocytopenia (ITP) patients infected with COVID-19 in China. We prospectively collected ITP patients infected with COVID-19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty-eight pre-existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty-seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25-2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO-RAs) (OR, 2.27; 95% CI, 1.60-3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09-3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12-5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63-7.64; p = 0.001), maintenance therapy including TPO-RAs (OR, 2.14; 95% CI, 1.17-3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17-7.91; p = 0.02). In this cohort study, we described the characteristics of pre-existing ITP patients infected with COVID-19 and identified several factors associated with poor outcomes.
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COVID-19 , Púrpura Trombocitopénica Idiopática , Trombocitopenia , Humanos , Adulto , Púrpura Trombocitopénica Idiopática/epidemiología , Púrpura Trombocitopénica Idiopática/terapia , Estudios de Cohortes , Estudios Prospectivos , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Trombopoyetina , Proteínas Recombinantes de Fusión , Receptores Fc , HidrazinasRESUMEN
The aim of this study was to assess the prevalence and the burden of difficult-to-treat primary ITP (pITP), defined by the need for another ITP treatment after romiplostim and eltrombopag. Adult patients were selected in the prospective, real-world CARMEN-France registry up to December 2021. Out of 821 adult patients with pITP, 29 had difficult-to-treat ITP (3.5%; 95% confidence interval [CI]: 2.3%-4.8% in total; 7.6%; 95% CI: 4.9%-10.2% of patients needing ≥2nd line treatment). The 3-year cumulative incidence of bleeding, infection and thrombosis was 100%, 24.1% and 13.8% respectively. The median cumulative duration of hospital stays was 31 days (median follow-up: 30.3 months).
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Púrpura Trombocitopénica Idiopática , Adulto , Humanos , Púrpura Trombocitopénica Idiopática/epidemiología , Púrpura Trombocitopénica Idiopática/terapia , Púrpura Trombocitopénica Idiopática/inducido químicamente , Prevalencia , Estudios Prospectivos , Trombopoyetina/efectos adversos , Receptores Fc , Benzoatos/efectos adversos , Hidrazinas/efectos adversos , Francia/epidemiología , Sistema de Registros , Proteínas Recombinantes de FusiónRESUMEN
Immune thrombocytopenia refractory to multiple thrombopoietin receptor agonists remains a challenging clinical problem. This commentary discusses and contextualizes the recent report on this entity from Moulis and colleagues, and how to move forward with these patients. Commentary on: Moulis et al. Difficult-to-treat primary immune thrombocytopenia in adults: Prevalence and burden. Results from the CARMEN-France Registry. Br J Haematol 2024;204:1476-1482.
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Púrpura Trombocitopénica Idiopática , Pirazoles , Trombocitopenia , Adulto , Humanos , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Receptores de Trombopoyetina/agonistas , Trombocitopenia/tratamiento farmacológico , Trombopoyetina/uso terapéutico , Benzoatos/uso terapéutico , Hidrazinas/uso terapéutico , Receptores Fc/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéuticoRESUMEN
Protein modifications importantly contribute to memory formation. Protein acetylation is a post-translational modification of proteins that regulates memory formation. Acetylation level is determined by the relative activities of acetylases and deacetylases. Crebinostat is a histone deacetylase inhibitor. Here we show that in an object recognition task, crebinostat facilitates memory formation by a weak training. Further, this compound enhances acetylation of α-tubulin, and reduces the level of histone deacetylase 6, an α-tubulin deacetylase. The results suggest that enhanced acetylation of α-tubulin by crebinostat contributes to its facilitatory effect on memory formation.