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1.
Dig Dis Sci ; 67(8): 3938-3947, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34365536

RESUMEN

BACKGROUND: Multimorbidity increases healthcare resource utilization. Little is known on specific comorbidity combinations. AIMS: To identify comorbidities associated with increased resource utilization among inpatients admitted for gastrointestinal bleeding (GIB). METHODS: This retrospective cross-sectional study, 1/2010-5/2018 at the University Hospital Zurich, Switzerland, analyzed electronic health records of patients with upper (UGIB) and lower (LGIB) GIB, focusing on length of stay (LOS) and 30-day readmissions for resource use and clinical outcomes, investigated by multivariable regression adjusted for antithrombotics. RESULTS: Of 1101 patients, 791 had UGIB and 310 LGIB, most often melena and bleeding diverticula, respectively. In UGIB, thromboembolic events showed a trend toward 27% increased LOS (1.27; 95% confidence interval [CI] 1.00-1.61), antithrombotics independently associated with 46% increased LOS (1.46; 95% CI 1.32-1.62). Cancer (odds ratio [OR] 2.86; 95% CI 1.68-4.88) independently associated with 30-day readmissions, anemia showed a trend (OR 1.68; 95% CI 1.00-2.84). In LGIB, none of the investigated comorbidities associated with increased LOS, but antithrombotics independently associated with 25% increased LOS (1.25; 95% CI 1.07-1.46). Atrial fibrillation/flutter (OR 2.69; 95% CI 1.06-6.82) and cancer (OR 4.76; 95% CI 1.40-16.20) associated strongly with 30-day readmissions. CONCLUSIONS: In both groups, cancer associated with 30-day readmissions, antithrombotics with increased LOS. Thromboembolic events and anemia showed clinically important trends in UGIB. Atrial fibrillation/flutter associated with 30-day readmissions in LGIB. Prospective studies are needed to investigate these complex multimorbid populations and establish appropriate guidelines.


Asunto(s)
Fibrilación Atrial , Pacientes Internos , Enfermedad Aguda , Comorbilidad , Estudios Transversales , Fibrinolíticos , Hemorragia Gastrointestinal/epidemiología , Humanos , Tiempo de Internación , Estudios Retrospectivos , Factores de Riesgo
2.
Bone Marrow Transplant ; 53(2): 175-179, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29058701

RESUMEN

Chemotherapy with G-CSF is used to mobilize peripheral stem cells in multiple myeloma (MM) patients, with plerixafor as a rescue strategy for poorly mobilizing patients. Preclinical studies suggested that the nonsteroidal anti-inflammatory drug meloxicam enhances the mobilization of CD34+ cells. In this single-center study, we evaluated whether adding meloxicam to chemotherapy/G-CSF mobilization increases peripheral hematopoietic CD34+ cell levels and reduces the need of using plerixafor. We prospectively compared two consecutive cohorts of MM patients in first remission mobilized with G-CSF and non-myelosuppressive chemotherapy with vinorelbine or gemcitabine. The second cohort additionally received oral meloxicam. The cohorts comprised 84 patients without meloxicam (-M) and 66 patients with meloxicam (+M). Meloxicam was well tolerated and associated with similar hematologic engraftment after transplantation and equal survival rates. However, the meloxicam group had higher CD34+ cell levels on day 8 of the mobilization procedure (53 200 versus 35 600 CD34+ cells/mL; P=0.007), and fewer patients needed >1 collection day (+M: 6 (9%) patients versus -M: 16 (19%) patients; P=0.04). This resulted in reduced plerixafor administrations (+M: 7 (11%) patients versus -M: 18 (21%) patients; P=0.03) and less costs. Our data suggest that meloxicam enhances the mobilization of hematopoietic CD34+ blood cells in MM patients.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Movilización de Célula Madre Hematopoyética/métodos , Meloxicam/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/cirugía , Trasplante de Células Madre de Sangre Periférica/métodos , Adulto , Anciano , Antiinflamatorios no Esteroideos/farmacología , Femenino , Humanos , Masculino , Meloxicam/farmacología , Persona de Mediana Edad , Mieloma Múltiple/patología
3.
Bone Marrow Transplant ; 50(4): 573-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25599166

RESUMEN

The occurrence of varicella zoster virus (VZV) reactivation is increased after allogeneic transplantation, whereas limited data are available for herpes zoster (HZ) after autologous SCT (ASCT). We determined the incidence and the prognostic significance of HZ and its correlation with VZV serology in 191 consecutive myeloma patients undergoing high-dose melphalan chemotherapy with ASCT. We found that VZV reactivation occurred in 57 (30%) patients, in 8.5% during induction and in 21.5% after ASCT peaking at 8 months after ASCT. Disease burden due to HZ was assessed as high or rather high in 70% of the patients. By immune fluorescence and Serion Elisa VZV IgG assessment, 90.8% of all patients had specific anti-VZV antibodies at ASCT. Lower specific antibody titers at transplantation were observed in patients with HZ after ASCT than in those without reactivation (P=0.009). Finally, OS was better in myeloma patients with HZ after ASCT compared with patients without HZ (P=0.007). Our data indicate that VZV reactivation after ASCT is a frequent event carrying a significant disease burden and it is associated with improved survival. Low levels of specific VZV antibodies at ASCT suggest increased vulnerability for VZV reactivation.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpes Zóster , Herpesvirus Humano 3/fisiología , Mieloma Múltiple , Trasplante de Células Madre , Activación Viral , Adulto , Anciano , Autoinjertos , Supervivencia sin Enfermedad , Femenino , Herpes Zóster/sangre , Herpes Zóster/etiología , Herpes Zóster/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Mieloma Múltiple/mortalidad , Mieloma Múltiple/terapia , Mieloma Múltiple/virología , Tasa de Supervivencia
4.
Br J Cancer ; 105(7): 970-4, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21878938

RESUMEN

BACKGROUND: High-dose chemotherapy with autologous stem cell transplantation is a cornerstone in the first-line treatment of multiple myeloma patients. However, only few factors have been identified affecting the outcome in such patients. We hypothesised that varying levels of mobilised CD34+ cells confer prognostic information in myeloma patients undergoing high-dose chemotherapy. METHODS: We determined circulating CD34+ cells at the day of peripheral stem cell collection in 158 consecutive myeloma patients between January 2001 and August 2010. Patients were stratified into two groups (super vs normal mobilisers) with a cutoff of 100,000 peripheral CD34+ cells per ml. RESULTS: We found that patients with more than 100,000 peripheral CD34+ cells per ml had a better overall survival (P=0.005) and a prolonged time to progression (P=0.0398) than patients with CD34+ cell counts below 100,000 CD34+ cells per ml. High levels of CD34+ cells were an independent marker for better overall survival and time to progression in a multivariate analysis that included disease stage, response at transplant, light-chain subtype, age, sex, and height. CONCLUSION: Our results suggest that high levels of mobilised peripheral CD34+ cells are associated with favourable outcome in myeloma patients undergoing autologous transplantation.


Asunto(s)
Antígenos CD34/sangre , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/fisiología , Mieloma Múltiple/sangre , Mieloma Múltiple/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Trasplante Autólogo
5.
Br J Cancer ; 103(2): 275-84, 2010 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-20628397

RESUMEN

BACKGROUND: CCAAT/enhancer-binding protein-alpha (CEBPA) is crucial for normal granulopoiesis and is frequently disrupted in acute myeloid leukaemia (AML). Increasing evidence suggests that CEBPA exerts its effects, in parts, by regulating specific microRNAs (miRNAs), as previously shown for miR-223. The aim of this study was to investigate the genome-wide pattern of miRNAs regulated by CEBPA in myeloid cells. METHODS: In Kasumi-1 cells, conditionally expressing CEBPA, we assessed the expression of 470 human miRNAs by microarray analysis. We further investigated the microarray results by qRT-PCR, luciferase reporter assays, and chromatin immunoprecipitation assays. RESULTS: In all, 18 miRNAs were more than two-fold suppressed or induced after CEBPA restoration. Among these 18 miRNAs, we focused on CEBPA-mediated regulation of the tumour-suppressive miR-29b. We observed that miR-29b is suppressed in AML patients with impaired CEBPA function or loss of chromosome 7q. We found that CEBPA selectively regulates miR-29b expression on its miR-29a/b1 locus on chromosome 7q32.3, whereas miR-29b2/c on chromosome 1q32.2 is not affected. CONCLUSION: This study reports the activation of the tumour-suppressive miR-29b by the haematopoietic key transcription factor CEBPA. Our data provide a rationale for miR-29b suppression in AML patients with loss of chromosome 7q or CEBPA deficiency.


Asunto(s)
Proteína alfa Potenciadora de Unión a CCAAT/farmacología , Leucemia Mieloide Aguda/genética , MicroARNs/genética , Proteínas Supresoras de Tumor/farmacología , Línea Celular Tumoral , Deleción Cromosómica , Regulación Leucémica de la Expresión Génica , Humanos
6.
Oncogene ; 29(7): 1062-72, 2010 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19966852

RESUMEN

The majority of patients with acute myeloid leukemia (AML) still die of their disease, and novel therapeutic concepts are needed. Timely expression of the hematopoietic master regulator PU.1 is crucial for normal development of myeloid and lymphoid cells. Targeted disruption of an upstream regulatory element (URE) located several kb upstream in the PU.1 promoter decreases PU.1 expression thereby inducing AML in mice. In addition, suppression of PU.1 has been observed in specific subtypes of human AML. Here, we identified nuclear factor-kappaB (NF-kappaB) to activate PU.1 expression through a novel site within the URE. We found sequence variations of this particular NF-kappaB site in 4 of 120 AML patients. These variant NF-kappaB sequences failed to mediate activation of PU.1. Moreover, the synergistic activation of PU.1 together with CEBPB through these variant sequences was also lost. Finally, AML patients with such variant sequences had suppressed PU.1 mRNA expression. This study suggests that changes of a single base pair in a distal element critically affect the regulation of the tumor suppressor gene PU.1 thereby contributing to the development of AML.


Asunto(s)
Elementos de Facilitación Genéticos/genética , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas/genética , Transactivadores/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Secuencia de Bases , Sitios de Unión , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Células COS , Estudios de Casos y Controles , Diferenciación Celular/genética , Línea Celular Tumoral , Chlorocebus aethiops , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , FN-kappa B/química , Neutrófilos/citología , Neutrófilos/metabolismo , Polimorfismo de Nucleótido Simple , Multimerización de Proteína , Estructura Cuaternaria de Proteína , Proteínas Proto-Oncogénicas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Homología de Secuencia de Ácido Nucleico , Transactivadores/metabolismo , Adulto Joven
7.
Br J Cancer ; 100(8): 1343-6, 2009 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-19277035

RESUMEN

CCAAT/enhancer binding protein alpha (CEBPA) mutations in AML are associated with favourable prognosis and are divided into N- and C-terminal mutations. The majority of AML patients have both types of mutations. We assessed the prognostic significance of single (n=7) and double (n=12) CEBPA mutations among 224 AML patients. Double CEBPA mutations conferred a decisively favourable overall (P=0.006) and disease-free survival (P=0.013). However, clinical outcome of patients with single CEBPA mutations was not different from CEBPA wild-type patients. In a multivariable analysis, only double -- but not single -- CEBPA mutations were identified as independent prognostic factors. These findings indicate heterogeneity within AML patients with CEBPA mutations.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/genética , Leucemia Mieloide Aguda/genética , Mutación , Médula Ósea/patología , Proteínas Potenciadoras de Unión a CCAAT/sangre , Intervalos de Confianza , Análisis Mutacional de ADN , Supervivencia sin Enfermedad , Genes Reporteros , Humanos , Cariotipificación , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Recuento de Leucocitos , Luciferasas/genética , Pronóstico , Análisis de Supervivencia , Sobrevivientes
8.
Oncogene ; 26(47): 6829-37, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17934489

RESUMEN

The current paradigm on leukemogenesis indicates that leukemias are propagated by leukemic stem cells. The genomic events and pathways involved in the transformation of hematopoietic precursors into leukemic stem cells are increasingly understood. This concept is based on genomic mutations or functional dysregulation of transcription factors in malignant cells of patients with acute myeloid leukemia (AML). Loss of the CCAAT/enhancer binding protein-alpha (CEBPA) function in myeloid cells in vitro and in vivo leads to a differentiation block, similar to that observed in blasts from AML patients. CEBPA alterations in specific subgroups of AML comprise genomic mutations leading to dominant-negative mutant proteins, transcriptional suppression by leukemic fusion proteins, translational inhibition by activated RNA-binding proteins, and functional inhibition by phosphorylation or increased proteasomal-dependent degradation. The PU.1 gene can be mutated or its expression or function can be blocked by leukemogenic fusion proteins in AML. Point mutations in the RUNX1/AML1 gene are also observed in specific subtypes of AML, in addition to RUNX1 being the most frequent target for chromosomal translocation in AML. These data are persuasive evidence that impaired function of particular transcription factors contributes directly to the development of human AML, and restoring their function represents a promising target for novel therapeutic strategies in AML.


Asunto(s)
Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Leucemia Mieloide/genética , Leucemia Mieloide/patología , Células Mieloides/patología , Transcripción Genética/fisiología , Enfermedad Aguda , Animales , Transformación Celular Neoplásica/metabolismo , Humanos , Leucemia Mieloide/metabolismo , Células Mieloides/metabolismo
9.
Br J Cancer ; 94(12): 1918-20, 2006 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-16735999

RESUMEN

The transcription factor PU.1 plays a crucial role during normal haematopoiesis in both myeloid cells and B-lymphocytes. Mice with a disruption in both alleles of the PU.1 locus were found to lack macrophages and B cells and had delayed appearance of neutrophils. In addition, critical decrease of PU.1 expression is sufficient to cause acute myeloid leukaemia (AML) and lymphomas in mice. Recently, we reported that heterozygous mutations in the PU.1 gene are present in some patients with AML. Thus, we hypothesised that PU.1 mutations might also contribute to the development of acute leukaemias of the B-cell lineage. Here, we screened 62 patients with B-cell acute lymphoblastic leukaemia (B-ALL) at diagnosis for genomic mutations by direct sequencing of all five exons of the PU.1 gene. We found no genomic alteration of the PU.1 gene suggesting that PU.1 mutations are not likely to be common in B-ALL.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Proto-Oncogénicas/genética , Transactivadores/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación , Reacción en Cadena de la Polimerasa
11.
Lancet ; 358(9295): 1760-5, 2001 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-11734232

RESUMEN

BACKGROUND: Early assessment of antiretroviral drug efficacy is important for prevention of the emergence of drug-resistant virus and unnecessary exposure to ineffective drug regimens. Current US guidelines for changing therapy are based on measurements of plasma HIV-1 RNA concentrations 4 or 8 weeks after the start of treatment with cut-off points of 0.75 or 1.00 log, respectively. We investigated the possibility of assessing drug efficacy from measurements of plasma HIV-1 concentrations made during the first week on therapy. METHODS: The kinetics of virus decay in plasma during the first 12 weeks of treatment was analysed for 124 HIV-1-infected patients being treated for the first time with a protease inhibitor. Patients with a continuous decline of HIV-1 concentrations and in whom HIV-1 was either undetectable or declined by more than 1.5 log at 12 weeks were defined as good responders; the rest were poor responders. FINDINGS: The individual virus decay rate constants (k) at day 6 correlated significantly (r>0.66, p<0.0001) with changes in HIV-1 concentrations at 4, 8, and 12 weeks, and correctly predicted 84% of the responses with a cut-off value of k=0.21 per day (in log scale). Reduction in plasma HIV-1 of less than 0.72 log by day 6 after initiation of therapy predicted poor long-term responses in more than 99% of patients. INTERPRETATION: These results suggest that changes in HIV-1 concentration at day 6 after treatment initiation are major correlates of longer-term virological responses. They offer a very early measure of individual long-term responses, suggesting that treatment could be optimised after only a few days of therapy.


Asunto(s)
Infecciones por VIH/sangre , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1 , ARN Viral/sangre , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Niño , Ensayos Clínicos como Asunto , Estudios de Cohortes , Humanos , Indinavir/uso terapéutico , Modelos Logísticos , Valor Predictivo de las Pruebas , ARN Viral/efectos de los fármacos , Ritonavir/uso terapéutico
12.
Mod Pathol ; 14(10): 929-36, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11598160

RESUMEN

Lymphoid interstitial pneumonitis (LIP), a frequent pulmonary complication in HIV-infected pediatric patients, is characterized histologically by marked infiltration of lymphoid cells. We sought to evaluate the nature and pathogenesis of the lymphoid infiltrates and to examine the relationship of LIP to pulmonary MALT lymphoma that has been described in pediatric HIV positive patients. To examine the potential contribution of chemokines and cytokines to the inflammatory cell recruitment in tissues involved by lymphoid interstitial pneumonitis from HIV-infected pediatric patients, RNA was extracted from paraffin-embedded tissues from five lung biopsies in four pediatric HIV-positive patients and from five control, normal lung biopsies in five HIV-negative patients and was analyzed by semiquantitative RT-PCR for the expression of cytokines (TNF-alpha, GM-CSF, IFN-gamma, IL-4, IL-6, IL-10, and IL-18) and chemokines (IP-10, Mig, regulated upon activation, normal T expressed and secreted [RANTES], and MIP1-alpha and beta) after normalization for G3PDH. Expression of IL-18 was increased, as well as expression of IFN-gamma-inducible chemokines IP-10 and Mig in LIP tissues compared with controls. RANTES and MIP1-alpha and -beta were also increased in pediatric LIP lesions compared with controls. In contrast, expression of TNF-alpha, GM-CSF, IL-10, and IL-6 was variable in LIP tissues and controls. In addition, clonality of the B-cell population was evaluated by VDJ-PCR. A polyclonal B-cell population was shown in all five biopsies from five patients with LIP; and in one patient with concurrent LIP and MALT lymphoma, a band of increased intensity was observed in the LIP biopsy that was identical in size to the monoclonal band in the concurrent MALT lymphoma biopsy. These results provide evidence of high-level expression of certain chemokines in lymphoid interstitial pneumonitis tissues and suggest that chemokines and cytokines may play an important role in the recruitment of inflammatory cell infiltrates into these tissues. In addition, LIP may represent an early stage of MALT lymphoma or an immunologic response to a chronic antigenic stimulus that may provide a milieu or microenvironment for the evolution of a monoclonal B-cell population.


Asunto(s)
Linfocitos B/patología , Quimiocinas/genética , Infecciones por VIH/complicaciones , Enfermedades Pulmonares Intersticiales/patología , Adolescente , Antígenos CD20/análisis , Linfocitos B/metabolismo , Complejo CD3/análisis , Niño , Preescolar , Células Clonales , Citocinas/genética , Femenino , Expresión Génica , Humanos , Cadenas kappa de Inmunoglobulina/análisis , Cadenas lambda de Inmunoglobulina/análisis , Inmunohistoquímica , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades Pulmonares Intersticiales/genética , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Linfoma de Células B de la Zona Marginal/complicaciones , Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B de la Zona Marginal/patología , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
J Infect Dis ; 184(2): 201-5, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11424019

RESUMEN

This study investigated whether immune restoration occurred in 26 human immunodeficiency virus (HIV) type 1-infected children treated first with indinavir for 16 weeks and then with combination antiretroviral therapy for >2 years. Compared with baseline, a significant, although modest, decrease in virus loads (maximum median, -0.86 log(10)) and increase in the number of CD4(+) lymphocytes, especially naive cells, were observed at several time points after 2 years. A maximum of 7% of treated children achieved undetectable viremia. There was a marked increase in the proliferative response and skin reactivity to recall antigens. However, responses to an HIV antigen remained depressed, and the production of interleukin-12 remained unchanged and abnormally low. The magnitude of virus suppression did not correlate with these measures of functional immune reconstitution. These findings suggest that long-term nonsuppressive antiretroviral therapy can induce limited improvement in immune function in pediatric AIDS patients and that the effect of suppressive treatments should be investigated.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Inhibidores de la Proteasa del VIH/uso terapéutico , Interleucina-12/biosíntesis , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Adolescente , Recuento de Linfocito CD4 , Niño , Preescolar , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Antígenos VIH/sangre , Humanos , Indinavir/uso terapéutico , Lamivudine/uso terapéutico , Masculino , Fitohemaglutininas/sangre , Factores de Tiempo , Resultado del Tratamiento , Carga Viral , Zidovudina/uso terapéutico
14.
Nat Med ; 7(4): 444-51, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11283671

RESUMEN

The transcription factor CCAAT/enhancer binding protein alpha, or C/EBPalpha, encoded by the CEBPA gene, is crucial for the differentiation of granulocytes. Conditional expression of C/EBPalpha triggers neutrophilic differentiation, and Cebpa knockout mice exhibit an early block in maturation. Dominant-negative mutations of CEBPA have been found in some patients with acute myeloid leukemia (AML), but not in AML with the t(8;21) translocation which gives rise to the fusion gene RUNX1-CBF2T1 (also known as AML1-ETO) encoding the AML1-ETO fusion protein. RUNX1-CBF2T1 positive-AML blasts had eight-fold lower CEBPA RNA levels and undetectable C/EBPalpha protein levels compared with other subgroups of AML patients. Conditional expression of RUNX1-CBF2T1 in U937 cells downregulated CEBPA mRNA, protein and DNA binding activity. AML1-ETO appears to suppress C/EBPalpha expression indirectly by inhibiting positive autoregulation of the CEBPA promoter. Conditional expression of C/EBPalpha in AML1-ETO-positive Kasumi-1 cells results in neutrophilic differentiation. We suggest that restoring C/EBPalpha expression will have therapeutic implications in RUNX1-CBF2T1-positive leukemias.


Asunto(s)
Proteína alfa Potenciadora de Unión a CCAAT/genética , Leucemia Mieloide Aguda/genética , Proteínas de Fusión Oncogénica/fisiología , Proteínas Proto-Oncogénicas , Factores de Transcripción/fisiología , Animales , Secuencia de Bases , Diferenciación Celular/genética , Cromosomas Humanos Par 21/genética , Cromosomas Humanos Par 8/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Cartilla de ADN/genética , Proteínas de Unión al ADN/genética , Regulación hacia Abajo , Humanos , Leucemia Mieloide Aguda/patología , Ratones , Proteínas de Fusión Oncogénica/genética , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Proteína 1 Compañera de Translocación de RUNX1 , Factores de Transcripción/genética , Translocación Genética
15.
J Infect Dis ; 183(7): 1116-20, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11237839

RESUMEN

Virologic and immunologic responses were examined for 33 human immunodeficiency virus (HIV)-infected children who participated for > or = 96 weeks in a phase 1/2 protocol of 16 weeks of indinavir monotherapy, followed by the addition of zidovudine and lamivudine. At week 96, a median increase of 199 CD4+ T cells/microL and a median decrease of 0.74 log(10) HIV RNA copies/mL were observed. The relationship between control of viral replication and CD4) T cell count was examined. Patients were categorized into 3 response groups on the basis of duration and extent of control of viral replication. Of 21 children with a transient decrease in virus load of > or = 0.7 log(10) HIV RNA copies/mL from baseline, 7 experienced sustained increases in CD4+, CD4+ CD45RA+, and CD4+ CD45RO+ T cell counts. CD4+ CD45RA+ (naive) T cells were the major contributor to CD4+ T cell expansion. Continued long-term immunologic benefit may be experienced by a subset of children, despite only transient virologic suppression.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH , Indinavir/uso terapéutico , Lamivudine/uso terapéutico , Zidovudina/uso terapéutico , Adolescente , Antígenos CD4/análisis , Recuento de Linfocito CD4 , Niño , Preescolar , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , VIH/aislamiento & purificación , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Antígenos Comunes de Leucocito/análisis , Masculino , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , ARN Viral/análisis , Carga Viral
16.
Nat Genet ; 27(3): 263-70, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11242107

RESUMEN

The transcription factor C/EBPalpha (for CCAAT/enhancer binding protein-alpha; encoded by the gene CEBPA) is crucial for the differentiation of granulocytes. Conditional expression of C/EBPalpha triggers neutrophilic differentiation, and no mature granulocytes are observed in Cebpa-mutant mice. Here we identify heterozygous mutations in CEBPA in ten patients with acute myeloid leukemia (AML). We found that five mutations in the amino terminus truncate the full-length protein, but did not affect a 30-kD protein initiated further downstream. The mutant proteins block wild-type C/EBPalpha DNA binding and transactivation of granulocyte target genes in a dominant-negative manner, and fails to induce granulocytic differentiation. Ours is the first report of CEBPA mutations in human neoplasia, and such mutations are likely to induce the differentiation block found in AML.


Asunto(s)
Proteína alfa Potenciadora de Unión a CCAAT/genética , Leucemia Mieloide Aguda/genética , Mutación , Secuencia de Bases , Proteína alfa Potenciadora de Unión a CCAAT/biosíntesis , Proteína alfa Potenciadora de Unión a CCAAT/química , Diferenciación Celular/genética , Núcleo Celular/metabolismo , Cartilla de ADN/genética , ADN de Neoplasias/metabolismo , Genes Dominantes , Granulocitos/patología , Heterocigoto , Humanos , Técnicas In Vitro , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Neutrófilos/patología , Eliminación de Secuencia , Activación Transcripcional
18.
J Immunol ; 165(9): 5262-8, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11046060

RESUMEN

During episodes of inflammation, multiple cell types release adenine nucleotides in the form of ATP, ADP, 5'-AMP, and adenosine. In particular, following activation, polymorphonuclear leukocytes release larger quantities of 5'-AMP. Extracellular 5'-AMP is metabolized to adenosine by surface-expressed 5'-ectonucleotidase (CD73). Adenosine liberated by this process activates surface adenosine A(2B) receptors, results in endothelial junctional reorganization, and promotes barrier function. We hypothesized that adenosine signaling to endothelia provides a paracrine loop for regulated expression of CD73 and enhanced endothelial barrier function. Using an in vitro microvascular endothelial model, we investigated the influence of 5'-AMP; adenosine; and adenosine analogues on CD73 transcription, surface expression, and function. Initial experiments revealed that adenosine and adenosine analogues induce CD73 mRNA (RT-PCR), surface expression (immunoprecipitation of surface biotinylated CD73), and function (HPLC analysis of etheno-AMP conversion to ethenoadenosine) in a time- and concentration-dependent fashion. Subsequent studies revealed that similar exposure conditions increase surface protein through transcriptional induction of CD73. Analysis of DNA-binding activity by EMSA identified a functional role for CD73 cAMP response element and, moreover, indicated that multiple cAMP agonists induce transcriptional activation of functional CD73. Induced CD73 functioned to enhance 5'-AMP-mediated promotion of endothelial barrier (measured as a paracellular flux of 70-kDa FITC-labeled tracer). These results provide an example of transcriptional induction of enzyme (CD73) by enzymatic product (adenosine) and define a paracrine pathway for the regulated expression of vascular endothelial CD73 and barrier function.


Asunto(s)
5'-Nucleotidasa/metabolismo , Adenosina/fisiología , Permeabilidad Capilar/fisiología , Endotelio Vascular/enzimología , Comunicación Paracrina/fisiología , 5'-Nucleotidasa/biosíntesis , 5'-Nucleotidasa/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Adulto , Células Cultivadas , AMP Cíclico/agonistas , AMP Cíclico/metabolismo , AMP Cíclico/fisiología , Dermis/irrigación sanguínea , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiología , Activación Enzimática , Humanos , ARN Mensajero/metabolismo , Receptores Purinérgicos P1/metabolismo , Activación Transcripcional
19.
Blood ; 96(8): 2641-8, 2000 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11023493

RESUMEN

The lineage-specific transcription factors GATA-1 and PU.1 can physically interact to inhibit each other's function, but the mechanism of repression of GATA-1 function by PU.1 has not been elucidated. Both the N terminus and the C terminus of PU.1 can physically interact with the C-terminal zinc finger of GATA-1. It is demonstrated that the PU.1 N terminus, but not the C terminus, is required for inhibiting GATA-1 function. Induced overexpression of PU.1 in K562 erythroleukemia cells blocks hemin-induced erythroid differentiation. In this system, PU.1 does not affect the expression of GATA-1 messenger RNA, protein, or nuclear localization. However, GATA-1 DNA binding decreases dramatically. By means of electrophoretic mobility shift assays with purified proteins, it is demonstrated that the N-terminal 70 amino acids of PU.1 can specifically block GATA-1 DNA binding. In addition, PU.1 had a similar effect in the G1ER cell line, in which the GATA-1 null erythroid cell line G1E has been transduced with a GATA-1-estrogen receptor fusion gene, which is directly dependent on induction of the GATA-1 fusion protein to effect erythroid maturation. Consistent with in vitro binding assays, overexpression of PU.1 blocked DNA binding of the GATA-1 fusion protein as well as GATA-1-mediated erythroid differentiation of these G1ER cells. These results demonstrate a novel mechanism by which function of a lineage-specific transcription factor is inhibited by another lineage-restricted factor through direct protein-protein interactions. These findings contribute to understanding how protein-protein interactions participate in hematopoietic differentiation and leukemogenesis. (Blood. 2000;96:2641-2648)


Asunto(s)
Proteínas de Unión al ADN/antagonistas & inhibidores , ADN/metabolismo , Células Precursoras Eritroides/metabolismo , Eritropoyesis/fisiología , Proteínas Proto-Oncogénicas/fisiología , Transactivadores/fisiología , Factores de Transcripción/antagonistas & inhibidores , Transporte Biológico , Diferenciación Celular/fisiología , Linaje de la Célula , Núcleo Celular/metabolismo , ADN de Neoplasias/metabolismo , Proteínas de Unión al ADN/metabolismo , Factores de Unión al ADN Específico de las Células Eritroides , Estradiol/farmacología , Factor de Transcripción GATA1 , Regulación Leucémica de la Expresión Génica/fisiología , Genes Sintéticos , Humanos , Células K562/metabolismo , Proteínas de Neoplasias/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/análisis , ARN Neoplásico/análisis , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/fisiología , Transactivadores/química , Transactivadores/genética , Factores de Transcripción/metabolismo , Transfección
20.
J Infect Dis ; 181(5): 1590-7, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10823758

RESUMEN

Monocyte-derived cytokine production by cord blood mononuclear cells (CBMC) from infants born to human immunodeficiency virus (HIV)-positive and -negative women was measured to determine whether monocyte dysfunction could contribute to the accelerated HIV disease of pediatric patients. Production of interleukin (IL)-12, but not that of tumor necrosis factor-alpha and IL-10, was reduced, compared with adult peripheral blood mononuclear cells (PBMC). This deficiency was more pronounced in infants of HIV-positive women, whose IL-12 production was also deficient. CBMC IL-12 levels were increased by interferon-gamma and CD40 ligand but remained deficient, compared with PBMC. IL-12 production was undetectable in 7 of 8 HIV-positive infants, in contrast to 21 of 26 uninfected infants. Uninfected infants of infected women exhibited an intermediate profile. These findings suggest that the maternal environment and/or exposure in utero to HIV products influence the newborn's immune response and that the differences between infants born to HIV-positive and -negative women may persist.


Asunto(s)
Infecciones por VIH , Transmisión Vertical de Enfermedad Infecciosa , Interleucina-12/sangre , Linfocitos/inmunología , Complicaciones Infecciosas del Embarazo/virología , Adulto , Fármacos Anti-VIH/uso terapéutico , Células Cultivadas , Preescolar , Citocinas/sangre , Femenino , Sangre Fetal/citología , Sangre Fetal/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , Humanos , Lactante , Recién Nacido , Interleucina-10/sangre , Interleucina-12/biosíntesis , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal , Análisis de Regresión , Factor de Necrosis Tumoral alfa/biosíntesis , Zidovudina/uso terapéutico
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