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1.
Cancer Sci ; 115(4): 1250-1260, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38327103

RESUMEN

Glasdegib is a potent, selective, oral inhibitor of the hedgehog signaling pathway. In this phase I study, previously untreated Japanese patients with acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes were treated with glasdegib (100 mg once daily) combinations: low-dose cytarabine (20 mg twice daily; cohort 1, n = 6; expansion cohort, n = 15); daunorubicin and cytarabine (60 mg/m2 i.v.; cohort 2, n = 6); or azacitidine (100 mg/m2 i.v.; cohort 3, n = 6). Patients, except cohort 2, were ineligible for intensive chemotherapy. The primary end-point was dose-limiting toxicity in cohorts 1-3 and disease-modifying response in the expansion cohort. Disease-modifying response rate was tested with the null hypothesis of 6.8%, which was set based on the results from the phase II BRIGHT AML 1003 study (NCT01546038). No dose-limiting toxicities were observed in cohorts 1 or 3; one patient in cohort 2 experienced a dose-limiting toxicity of grade 3 erythroderma. The most common grade ≥3 treatment-related adverse events were neutropenia and thrombocytopenia (66.7% each) in cohort 1 and thrombocytopenia (60.0%) in the expansion cohort. In the expansion cohort, the disease-modifying response rate was 46.7% (90% confidence interval, 24.4-70.0; p < 0.0001), with all patients achieving either a complete response or complete response with incomplete blood count recovery. Median overall survival was 13.9 months. In this study, the primary disease-modifying response end-point with glasdegib plus low-dose cytarabine was met. The study confirms the safety and efficacy of glasdegib plus low-dose cytarabine in Japanese patients with AML ineligible for intensive chemotherapy.


Asunto(s)
Bencimidazoles , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Compuestos de Fenilurea , Trombocitopenia , Humanos , Japón , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Proteínas Hedgehog , Leucemia Mieloide Aguda/metabolismo , Citarabina/efectos adversos , Síndromes Mielodisplásicos/tratamiento farmacológico
2.
J Immunol ; 207(4): 1078-1086, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34341172

RESUMEN

Emergency granulopoiesis, also known as demand-adapted granulopoiesis, is defined as the response of an organism to systemic bacterial infections, and it results in neutrophil mobilization from reservoir pools and increased myelopoiesis in the bone marrow. Indirect and direct initiating mechanisms of emergency granulopoiesis have been hypothesized. However, the detailed mechanism of hyperactive myelopoiesis in the bone marrow, which leads to granulocyte left shift, remains unknown. In this study, we report that TLR4 is expressed on granulo-monocytic progenitors, as well as mobilized human peripheral blood CD34+ cells, which account for 0.2% of monocytes in peripheral blood, and ∼ 10% in bone marrow. LPS, a component of Gram-negative bacteria that results in a systemic bacterial infection, induces the differentiation of peripheral blood CD34+ cells into myelocytes and monocytes in vitro via the TLR4 signaling pathway. Moreover, CD34+ cells directly responded to LPS stimulation by activating the MAPK and NF-κB signaling pathways, and they produced IL-6 that promotes emergency granulopoiesis by phosphorylating C/EBPα and C/EBPß, and this effect was suppressed by the action of an IL-6 receptor inhibitor. This work supports the finding that TLR is expressed on human hematopoietic stem and progenitor cells, and it provides evidence that human hematopoietic stem and progenitor cells can directly sense pathogens and produce cytokines exerting autocrine and/or paracrine effects, thereby promoting differentiation.


Asunto(s)
Granulocitos/metabolismo , Células Madre Hematopoyéticas/metabolismo , Interleucina-6/metabolismo , Transducción de Señal/fisiología , Células Madre/metabolismo , Receptor Toll-Like 4/metabolismo , Adaptación Fisiológica/fisiología , Antígenos CD34/metabolismo , Médula Ósea/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Diferenciación Celular/fisiología , Citocinas/metabolismo , Regulación de la Expresión Génica/fisiología , Células Precursoras de Granulocitos/metabolismo , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Monocitos/metabolismo , Mielopoyesis/fisiología
3.
Ther Drug Monit ; 39(5): 514-521, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28834922

RESUMEN

BACKGROUND: Although voriconazole (VRCZ) is metabolized to VRCZ N-oxide principally by CYP2C19, VRCZ clearance is affected by multiple factors. In this study, we investigated the relationship between the CYP2C19 phenotype using the VRCZ-to-VRCZ N-oxide plasma concentration ratio (VRCZ/N-oxide) and demographic and clinical characteristics of Japanese patients taking VRCZ. METHODS: A total of 65 Japanese patients taking VRCZ for prophylaxis or treatment of fungal infection were enrolled in this study. Stepwise selection multiple linear regression analysis was performed to investigate the effect of factors on the VRCZ/N-oxide ratio. RESULTS: In patients not undergoing concurrent treatment with a drug influencing CYP2C19 activity (n = 54), the VRCZ/N-oxide ratio with definite thresholds for CYP2C19 genotypes, CYP2C19*1/*1, *1/*2 + *1/*3 + *2/*17, and *2/*2 + *2/*3, was specifically identified in patients taking VRCZ (<0.48, ≥0.48 < and <0.82 and ≥0.82). However, the VRCZ/N-oxide ratio could not be predicted based solely on the CYP2C19 genotype (R = 0.053). The route of VRCZ administration, C-reactive protein concentration determined on the same day as VRCZ plasma concentration measurement, CYP2C19 extensive metabolizer, and patient age were independent factors influencing the VRCZ/N-oxide ratio (R = 0.489, standardized regression coefficient = 0.385, 0.380, -0.231, and 0.231; P = 0.001, 0.001, 0.032, and 0.036, respectively). CONCLUSIONS: It is possible to comprehensively evaluate CYP2C19 activity using the actual measured value of the VRCZ/N-oxide ratio in patients taking VRCZ. The predictive performance of the VRCZ/N-oxide ratio was improved by including the route of administration, C-reactive protein level, and patient age in addition to the CYP2C19 genotype as predictive factors.


Asunto(s)
Antifúngicos/sangre , Citocromo P-450 CYP2C19/genética , Óxidos/sangre , Voriconazol/sangre , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Proteína C-Reactiva/metabolismo , Demografía , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Polimorfismo Genético/genética , Adulto Joven
4.
Rinsho Ketsueki ; 58(7): 743-748, 2017.
Artículo en Japonés | MEDLINE | ID: mdl-28781268

RESUMEN

A 64-year-old woman was admitted to our hospital to undergo allogeneic stem cell transplantation. She was diagnosed with polycythemia vera with a JAK2 V617F mutation 7 years ago. She was administered ruxolitinib for splenomegaly two years prior to admission but this was discontinued because of progressive pancytopenia. One months after cessation of ruxolitinib, she developed acute myeloid leukemia transformed from post-polycythemia vera myelofibrosis. Although she achieved complete remission after induction therapy, 8-finger-breadth splenomegaly remained below the left costal margin. Ruxolitinib was re-administered following two courses of consolidation therapy. She underwent unrelated peripheral blood stem cell transplantation. Ruxolitinib was administered until the day before transplantation, and the spleen was palpated in 4-finger breadth below costal arc. Neutrophil engraftment was achieved 13 days after transplantation. In allogeneic stem cell transplantation, splenomegaly is one of the risk factors for engraftment failure and/or therapy-related mortality. Hence, a smaller spleen size can theoretically improve the outcome after transplantation. The administration of ruxolitinib prior to transplantation may have contributed to engraftment with a non-invasive reduction in the size of the spleen.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda/terapia , Mielofibrosis Primaria/complicaciones , Pirazoles/uso terapéutico , Esplenomegalia/tratamiento farmacológico , Femenino , Humanos , Leucemia Mieloide Aguda/etiología , Persona de Mediana Edad , Nitrilos , Pirimidinas , Acondicionamiento Pretrasplante , Trasplante Homólogo
5.
Biol Blood Marrow Transplant ; 22(4): 627-636, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26740374

RESUMEN

Hemophagocytic syndrome (HPS) is frequently associated with hematopoietic stem cell transplantation and is treated with some benefit derived from TNF-α inhibitors. However, the mechanisms of how HPS occurs and how a TNF-α inhibitor exerts some benefit to HPS management have remained unclear. We evaluated the effect of toll-like receptor (TLR) ligands, especially focusing on cytosine-phosphorothionate-guanine oligodeoxynucleotide (CpG), a TLR9 ligand, on HPS in mice that underwent transplantation with syngeneic or allogeneic bone marrow (BM) cells (Syn-BMT, Allo-BMT), or with allogeneic BM cells plus splenocytes to promote graft-versus-host disease (GVHD mice). Hemophagocytosis was a common feature early after all BMT, but it subsided in Syn-BMT and Allo-BMT mice. In GVHD mice, however, hemophagocytosis persisted and was accompanied by upregulated production of IFN-γ but not TNF-α, and it was suppressed by blockade of IFN-γ but not TNF-α. A single injection of the TLR9 ligand CpG promoted HPS in all BMT mice and was lethal in GVHD mice, accompanied by greatly upregulated production of TNF-α, IL-6, and IFN-γ. Blocking of TNF-α, but not IL-6 or IFN-γ, suppressed CpG-induced HPS in all BMT mice and rescued GVHD mice from CpG-induced mortality. Thus, TLR9 signaling mediates TNF-α-driven HPS in BMT mice and is effectively treated through TNF-α inhibition.


Asunto(s)
Trasplante de Médula Ósea/métodos , Linfohistiocitosis Hemofagocítica/inmunología , Oligodesoxirribonucleótidos/farmacología , Receptor Toll-Like 9/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Células de la Médula Ósea/citología , Células de la Médula Ósea/inmunología , Trasplante de Médula Ósea/efectos adversos , Islas de CpG/inmunología , Etanercept/farmacología , Rayos gamma , Regulación de la Expresión Génica , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/patología , Interferón gamma/antagonistas & inhibidores , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Linfocitos/citología , Linfocitos/inmunología , Linfohistiocitosis Hemofagocítica/etiología , Linfohistiocitosis Hemofagocítica/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Oligodesoxirribonucleótidos/antagonistas & inhibidores , Transducción de Señal , Receptor Toll-Like 9/genética , Trasplante Homólogo , Trasplante Isogénico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Irradiación Corporal Total
6.
Blood ; 119(4): 1036-44, 2012 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-22049517

RESUMEN

Mammalian erythroblasts undergo enucleation, a process thought to be similar to cytokinesis. Although an assemblage of actin, non-muscle myosin II, and several other proteins is crucial for proper cytokinesis, the role of non-muscle myosin II in enucleation remains unclear. In this study, we investigated the effect of various cell-division inhibitors on cytokinesis and enucleation. For this purpose, we used human colony-forming unit-erythroid (CFU-E) and mature erythroblasts generated from purified CD34(+) cells as target cells for cytokinesis and enucleation assay, respectively. Here we show that the inhibition of myosin by blebbistatin, an inhibitor of non-muscle myosin II ATPase, blocks both cell division and enucleation, which suggests that non-muscle myosin II plays an essential role not only in cytokinesis but also in enucleation. When the function of non-muscle myosin heavy chain (NMHC) IIA or IIB was inhibited by an exogenous expression of myosin rod fragment, myosin IIA or IIB, each rod fragment blocked the proliferation of CFU-E but only the rod fragment for IIB inhibited the enucleation of mature erythroblasts. These data indicate that NMHC IIB among the isoforms is involved in the enucleation of human erythroblasts.


Asunto(s)
Eritroblastos/citología , Eritroblastos/metabolismo , Eritropoyesis , Miosina Tipo IIB no Muscular/metabolismo , Amidas/farmacología , Aminoquinolinas/farmacología , Células Cultivadas , Citocinesis/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Eritroblastos/efectos de los fármacos , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/efectos de los fármacos , Células Precursoras Eritroides/metabolismo , Eritropoyesis/efectos de los fármacos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos , Proteínas de Microfilamentos/antagonistas & inhibidores , Miosinas/antagonistas & inhibidores , Miosina Tipo IIA no Muscular/antagonistas & inhibidores , Miosina Tipo IIA no Muscular/genética , Miosina Tipo IIA no Muscular/metabolismo , Miosina Tipo IIB no Muscular/antagonistas & inhibidores , Miosina Tipo IIB no Muscular/genética , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Piridinas/farmacología , Pirimidinas/farmacología , Proteínas Recombinantes de Fusión/metabolismo , Proteína de Unión al GTP rac1/antagonistas & inhibidores , Quinasas Asociadas a rho/antagonistas & inhibidores
7.
Blood ; 115(22): 4569-79, 2010 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-20348392

RESUMEN

Recent studies have shown that anemia is commonly observed after exposure to pathogens or pathogen-derived products, which are recognized via Toll-like receptor 9 (TLR9). In the current study, we demonstrate that CpG oligodeoxynucleotide-2006, a TLR9 ligand with phosphodiester (PO; 2006-PO) but not with the phosphorothioate backbone, selectively inhibits the erythroid growth derived from human CD34(+) cells. The 2006-PO was internalized by the erythroid progenitors within 30 minutes; however, expression of TLR9 mRNA was not detected in these cells. The 2006-PO directly inhibited burst-forming unit-erythroid growth, resulted in the accumulation of cells in S and G(2)/M phases, and increased cell size and frequency of apoptotic cells. These features were similar to those observed in erythroid progenitors infected with human parvovirus B19 that causes pure red cell aplasia. The consensus sequence of 2006-PO was defined as 5'-GTTTTGT-3', which was located in the P6-promoter region of B19 and inhibited erythroid growth in a sequence-specific manner and down-regulated expression of erythropoietin receptor (EPOR) mRNA and EPOR. B19 genome extracted from serum also inhibited erythroid growth and down-regulated expression of EPOR on glycophorin A(+) cells. These results provide a possible insight into our understanding of the mechanisms of human parvovirus B19-mediated inhibition of erythropoiesis.


Asunto(s)
Células Precursoras Eritroides/citología , Células Precursoras Eritroides/efectos de los fármacos , Oligodesoxirribonucleótidos/genética , Oligodesoxirribonucleótidos/farmacología , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/patogenicidad , Anemia/sangre , Anemia/etiología , Anemia/genética , Secuencia de Bases , Secuencia de Consenso , Cartilla de ADN/genética , Regulación hacia Abajo , Células Precursoras Eritroides/metabolismo , Eritropoyesis/efectos de los fármacos , Eritropoyesis/genética , Genoma Viral , Humanos , Técnicas In Vitro , Factores de Transcripción de Tipo Kruppel/sangre , Ligandos , Oligodesoxirribonucleótidos/sangre , ARN Mensajero/sangre , ARN Mensajero/genética , Receptores de Eritropoyetina/sangre , Receptores de Eritropoyetina/genética , Receptor Toll-Like 9/sangre
9.
Int J Hematol ; 113(4): 600-605, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33387296

RESUMEN

Blinatumomab enhances survival in patients with B-cell precursor acute lymphoblastic leukemia (B-ALL) by inducing T cell activation. However, approximately 50% of patients with relapsed or refractory B-ALL do not respond to blinatumomab, and the correlation between T cell phenotype and blinatumomab response remains unclear. To assess this correlation, we longitudinally compared immune checkpoint molecules in T cells before and during blinatumomab treatment between a responder and non-responder. In the responder, the expression level of granzyme B increased following infusion of blinatumomab and complete remission was achieved. On the other hand, the non-responder consistently expressed higher levels of programmed death-1 (PD-1), T cell immunoglobulin and mucin domain 3 (Tim-3), and T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) in CD8 + T cells than the responder during blinatumomab treatment and showed no response despite the addition of two donor lymphocyte infusions. Furthermore, the residual tumors in bone marrow after blinatumomab treatment showed increased expression of immune checkpoint ligands: PD-L1 (PD-1 ligand), Galectin-9 (Tim-3 ligand), PD-L2 (PD-1 ligand) and CD155 (TIGIT ligand). In conclusion, immune checkpoint molecule levels could correlate with response to blinatumomab.


Asunto(s)
Anticuerpos Biespecíficos/farmacología , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Proteínas de Punto de Control Inmunitario/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Anticuerpos Biespecíficos/uso terapéutico , Médula Ósea/patología , Humanos , Proteínas de Punto de Control Inmunitario/metabolismo , Inmunofenotipificación , Activación de Linfocitos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T/inmunología
10.
Sci Rep ; 10(1): 11806, 2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32678227

RESUMEN

The molecular mechanisms involved in the terminal differentiation of erythroblasts have been elucidated by comparing enucleation and cell division. Although various similarities and differences between erythroblast enucleation and cytokinesis have been reported, the mechanisms that control enucleation remain unclear. We previously reported that dynein and microtubule-organizing centers mediated the polarization of nuclei in human erythroblasts. Moreover, the accumulation of F-actin was noted during the enucleation of erythroblasts. Therefore, during enucleation, upstream effectors in the signal transduction pathway regulating dynein or actin, such as cell division control protein 42 homolog (Cdc42), may be crucial. We herein investigated the effects of the Cdc42 inhibitor, CASIN, on cytokinesis and enucleation in colony-forming units-erythroid (CFU-Es) and mature erythroblasts (day 10). CASIN blocked the proliferation of CFU-Es and their enucleation in a dose-dependent manner. Dynein adopted an island-like distribution in the cytoplasm of non-treated CFU-Es, but was concentrated near the nucleus as a dot and co-localized with γ-tubulin in CASIN-treated cells. CASIN blocked the accumulation of F-actin in CFU-Es and day 10 cells. These results demonstrated that Cdc42 plays an important role in cytokinesis, nuclear polarization and nuclear extrusion through a relationship with dynein and actin filament organization during the terminal differentiation of erythroblasts.


Asunto(s)
Actomiosina/metabolismo , Diferenciación Celular , Eritroblastos/citología , Eritroblastos/metabolismo , Proteína de Unión al GTP cdc42/genética , Biomarcadores , Diferenciación Celular/genética , Núcleo Celular/metabolismo , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/metabolismo , Eritropoyesis/genética , Técnica del Anticuerpo Fluorescente , Expresión Génica , Humanos , Inmunohistoquímica , Proteína de Unión al GTP cdc42/metabolismo
11.
Intern Med ; 58(23): 3461-3468, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31391391

RESUMEN

A 72-year-old man presented with a 6-month history of systemic edema. Hyperpigmentation, hemangioma, pleural effusion, IgG-kappa-type monoclonal protein, high vascular endothelial growth factor values, renal failure, and nerve conduction study abnormalities were also present. Multiparameter flow cytometry (MFC) showed 0.2% neoplastic plasma cells (CD38-, CD56-, and kappa-positive; CD19-, CD27-, and lambda-negative) in the bone marrow leading to POEMS syndrome. Cases involving kappa-type POEMS syndrome are extremely rare. A kidney biopsy revealed membranous proliferative glomerulonephritis-like changes in our case. Lenalidomide-dexamethasone therapy improved the renal function. Detection of neoplastic plasma cells by MFC was useful for the accurate diagnosis and treatment evaluation.


Asunto(s)
Dexametasona/administración & dosificación , Factores Inmunológicos/administración & dosificación , Lenalidomida/administración & dosificación , Síndrome POEMS/tratamiento farmacológico , Paraproteinemias/tratamiento farmacológico , Anciano , Citometría de Flujo/métodos , Glomerulonefritis/etiología , Hemangioma/etiología , Humanos , Inmunoglobulina G/metabolismo , Cadenas kappa de Inmunoglobulina/metabolismo , Masculino , Síndrome POEMS/diagnóstico , Trastornos de la Pigmentación/etiología , Células Plasmáticas/patología , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factores de Crecimiento Endotelial Vascular
12.
Intern Med ; 58(21): 3153-3156, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31292386

RESUMEN

A 53-year-old woman presented at our hospital due to nasal bleeding and petechiae with profound thrombocytopenia (0.4×109/L). Her platelet count returned to the normal range immediately following a platelet transfusion. In this case, tea brewed from Taxus yunnanensis was the only suspected agent ingested prior to the onset of thrombocytopenia while all other etiologies for thrombocytopenia were excluded. A re-exposure test to Taxus yunnanensis resulted in the recurrence of acute thrombocytopenia. The association of thrombocytopenia with substances other than drugs has so far only been rarely described and to the best of our knowledge, this is the first reported case of thrombocytopenia caused by Taxus yunnanensis.


Asunto(s)
Bebidas/efectos adversos , Extractos Vegetales/efectos adversos , Taxus/efectos adversos , Trombocitopenia/etiología , Femenino , Humanos , Persona de Mediana Edad , Recuento de Plaquetas , Transfusión de Plaquetas , Trombocitopenia/terapia
13.
Exp Hematol ; 72: 14-26.e1, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30797950

RESUMEN

More than 2million human erythroblasts extrude their nuclei every second in bone marrow under hypoxic conditions (<7% O2). Enucleation requires specific signal transduction pathways and the local assembly of contractile actomyosin rings. However, the energy source driving these events has not yet been identified. We examined whether different O2 environments (hypoxic [5% O2] and normoxic [21% O2] conditions) affected human CD34+ cell erythroblast differentiation. We also investigated the regulatory mechanisms underlying energy production in erythroblasts during terminal differentiation under 5% or 21% O2 conditions. The results obtained revealed that the enucleation ratio and intracellular levels of adenosine triphosphate (ATP), lactate dehydrogenase (LDH) M3H, and hypoxia-inducible factor 1α in erythroblasts during terminal differentiation were higher under the 5% O2 condition than under the 21% O2 condition. We also found that the enzymatic inhibition of glyceraldehyde 3-phosphate dehydrogenase and LDH, key enzymes in anaerobic glycolysis, blocked the proliferation of colony-forming units-erythroid and enucleation of erythroblasts, and also reduced ATP levels in erythroblasts under both hypoxic and normoxic conditions. Under both conditions, phosphorylation of the Ser232, Ser293, and Ser300 residues in pyruvate dehydrogenase (inactive state of the enzyme) in erythroblasts was involved in regulating the pathway governing energy metabolism during erythroid terminal differentiation. This reaction may be mediated by pyruvate dehydrogenase kinase (PDK) 4, the major PDK isozyme expressed in erythroblasts undergoing enucleation. Collectively, these results suggest that ATP produced by anaerobic glycolysis is the main source of energy for human erythroblast enucleation in the hypoxic bone marrow environment.


Asunto(s)
Adenosina Trifosfato/biosíntesis , Eritroblastos/metabolismo , Glucólisis/fisiología , Anaerobiosis/fisiología , Antígenos CD34/metabolismo , Eritroblastos/citología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Lactato Deshidrogenasa 5/metabolismo , Fosforilación/fisiología , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo
15.
Int J Hematol ; 108(2): 130-138, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29691802

RESUMEN

Although the neuronal protein α-synuclein (α-syn) is thought to play a central role in the pathogenesis of Parkinson's disease (PD), its physiological function remains unknown. It is known that α-syn is also abundantly expressed in erythrocytes. However, its role in erythrocytes is also unknown. In the present study, we investigated the localization of α-syn in human erythroblasts and erythrocytes. Protein expression of α-syn increased during terminal differentiation of erythroblasts (from day 7 to day 13), whereas its mRNA level peaked at day 11. α-syn was detected in the nucleus, and was also seen in the cytoplasm and at the plasma membrane after day 11. In erythroblasts undergoing nucleus extrusion (day 13), α-syn was detected at the periphery of the nucleus. Interestingly, we found that recombinant α-syn binds to trypsinized inside-out vesicles of erythrocytes and phosphatidylserine (PS) liposomes. The dissociation constants for binding to PS/phosphatidylcholine (PC) liposomes of N-terminally acetylated (NAc) α-syn was lower than that of non NAc α-syn. This suggests that N-terminal acetylation plays a significant functional role. The results of the present study collectively suggest that α-syn is involved in the enucleation of erythroblasts and the stabilization of erythroid membranes.


Asunto(s)
Diferenciación Celular/genética , Eritroblastos/metabolismo , Eritrocitos/metabolismo , Eritrocitos/fisiología , alfa-Sinucleína/metabolismo , Acetilación , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Eritroblastos/citología , Eritrocitos/citología , Expresión Génica , Humanos , Liposomas/metabolismo , Fosfatidilcolinas/metabolismo , Fosfatidilserinas/metabolismo , Unión Proteica , ARN Mensajero/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/genética
17.
Cancer Chemother Pharmacol ; 78(1): 111-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27217047

RESUMEN

BACKGROUND: Tacrolimus is metabolized by cytochrome P450 (CYP) 3A4 and 3A5. We investigated the influence of CYP3A5 polymorphism and concurrent use of azole antifungal agents (AZ) on the pharmacokinetics of a once-daily modified-release tacrolimus formulation (Tac-QD) in patients after hematopoietic stem cell transplantation (HSCT). DESIGN AND METHODS: Twenty-four patients receiving allogeneic HSCT were enrolled. Genotyping for CYP3A5*3 was done by a PCR-restriction fragment length polymorphism method. Trough blood concentrations (C0) of tacrolimus were measured by chemiluminescence magnetic microparticle immunoassay. Continuous infusion of tacrolimus was administered from the day before transplantation and was switched to Tac-QD after adequate oral intake. RESULTS: Thirteen patients had a CYP3A5*3/*3 genotype, and 11 patients had a CYP3A5*1/*1 or *1/*3 genotype. No significant difference was observed in daily dosages and the C0 of tacrolimus between the two genotype groups without AZ. However, in patients who were co-administered AZ, the C0 values of tacrolimus were higher in patients with the CYP3A5*3/*3 allele than with the CYP3A5*1 allele (P = 0.034), although daily doses of Tac-QD in patients with CYP3A5*3/*3 were significantly lower than those with the CYP3A5*1 allele (P = 0.041). The cumulative incidence of acute kidney injury was higher in patients with the CYP3A5*3/*3 than with the CYP3A5*1 allele when AZ was co-administered. The decrement for daily dosage of Tac-QD was significantly greater in patients expressing the CYP3A5*3/*3 than the CYP3A5*1 allele. CONCLUSIONS: CYP3A5 genotyping may be useful for safe and effective immunosuppressive therapy with Tac-QD in HSCT patients in whom the use of AZ is anticipated.


Asunto(s)
Lesión Renal Aguda/epidemiología , Citocromo P-450 CYP3A/genética , Trasplante de Células Madre Hematopoyéticas/métodos , Inmunosupresores/administración & dosificación , Tacrolimus/administración & dosificación , Adulto , Anciano , Alelos , Antifúngicos/administración & dosificación , Antifúngicos/farmacología , Azoles/administración & dosificación , Azoles/farmacología , Estudios de Cohortes , Preparaciones de Acción Retardada , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Femenino , Genotipo , Humanos , Inmunosupresores/farmacocinética , Masculino , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Prospectivos , Tacrolimus/farmacocinética , Adulto Joven
18.
Exp Hematol ; 44(4): 247-56.e12, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26724640

RESUMEN

Mammalian erythroblasts undergo enucleation through a process thought to be similar to cytokinesis. Microtubule-organizing centers (MTOCs) mediate organization of the mitotic spindle apparatus that separates the chromosomes during mitosis and are known to be crucial for proper cytokinesis. However, the role of MTOCs in erythroblast enucleation remains unknown. We therefore investigated the effect of various MTOC inhibitors on cytokinesis and enucleation using human colony-forming units-erythroid (CFU-Es) and mature erythroblasts generated from purified CD34(+) cells. We found that erythro-9-[3-(2-hydroxynonyl)]adenine (EHNA), a dynein inhibitor, and monastrol, a kinesin Eg5 inhibitor, as well as various inhibitors of MTOC regulators, including ON-01910 (Plk-1), MLN8237 (aurora A), hesperadin (aurora B), and LY294002 (PI3K), all inhibited CFU-E cytokinesis. Among these inhibitors, however, only EHNA blocked enucleation. Moreover, terminally differentiated erythroblasts expressed only dynein; little or none of the other tested proteins was detected. Over the course of the terminal differentiation of human erythroblasts, the fraction of cells with nuclei at the cell center declined, whereas the fraction of polarized cells, with nuclei shifted to a position near the plasma membrane, increased. Dynein inhibition impaired nuclear polarization, thereby blocking enucleation. These data indicate that dynein plays an essential role not only in cytokinesis but also in enucleation. We therefore conclude that human erythroblast enucleation is a process largely independent of MTOCs, but dependent on dynein.


Asunto(s)
Diferenciación Celular , Dineínas/metabolismo , Eritroblastos/citología , Eritroblastos/metabolismo , División Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Dineínas/antagonistas & inhibidores , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/efectos de los fármacos , Células Precursoras Eritroides/metabolismo , Eritropoyesis , Expresión Génica , Glicina/análogos & derivados , Glicina/farmacología , Humanos , Centro Organizador de los Microtúbulos/metabolismo , Proteínas Motoras Moleculares/genética , Proteínas Motoras Moleculares/metabolismo , Sulfonas/farmacología , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
20.
Immunol Lett ; 150(1-2): 23-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23274961

RESUMEN

Although there exist case reports describing the association of clonal expansion of γδ T cells with chronic acquired pure red cell aplasia (PRCA), there is no consensus regarding whether clonal expansion of γδ T cells are generally found in chronic PRCA. We examined the γδ T cell receptor repertoire in 19 PRCA patients and found that there was a difference in γδ T-cell repertoires between PRCA patients and healthy donors. We observed an increase in Vδ1 γδ T cells and a decrease in Vδ2 T cells in PRCA patients. CDR3δ1 size distribution patterns were skewed in 9 out of 13 PRCA patients examined, although the skewing was also observed in 7 out of 10 healthy individuals. No significant changes were present in CDR3δ1 size distribution between PRCA patients and healthy donors. Moreover, no apparent consensus amino acid motifs were identified in PRCA patients. Expansion of Vδ1 T cells and depletion of Vδ2 T cells are unique features for chronic acquired PRCA but expansion of Vδ1 T cells does not seem to be the consequence of CDR3-dependent selection. We conclude that clonal expansion of Vδ1 T cells is not a general feature for chronic acquired PRCA.


Asunto(s)
Regiones Determinantes de Complementariedad/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Aplasia Pura de Células Rojas/inmunología , Aplasia Pura de Células Rojas/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Adulto , Anciano , Secuencia de Aminoácidos , Estudios de Casos y Controles , Regiones Determinantes de Complementariedad/química , Regiones Determinantes de Complementariedad/inmunología , Secuencia de Consenso , Femenino , Humanos , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Aplasia Pura de Células Rojas/tratamiento farmacológico , Subgrupos de Linfocitos T/citología
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