Asunto(s)
Azacitidina/uso terapéutico , Metilación de ADN , Proteínas de Unión al ADN/genética , Mutación/genética , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas/genética , Adulto , Anciano , Antimetabolitos Antineoplásicos/uso terapéutico , Dioxigenasas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
Anthropometry is the technique of expressing body shape in quantitative terms. The measurements are compared with the standard growth curves for the general population and expressed as a SD score or percentiles. The comparison of the different parameters with normal standards requires: standardized landmarks on the body, standardized methods of taking measurements, and standard equipment. Skeletal dysplasias generally present with disproportionate short stature, that may be caused primarily by a short trunk or short limbs. If short limbs are observed, the reduction may affect the proximal (rhizomelic), the middle (mesomelic) or distal (acromelic) segments. Anthropometric measurements should include all the segments of the arms and the legs with a comparison with the normal standards for height age. Short stature homeobox- containing (SHOX) gene defects determine a highly variable phenotype, that includes an osteochondrodysplasia with mesomelic short stature and Madelung deformity, but also presentations without evident malformations. Anthropometric indicators of SHOX deficiency are: disproportionate short stature, reduction of lower limb, reduction of the ratio between arm span and forearm length with respect to height, increase in the sitting/ height stature ratio, increase in limb circumference (arm, forearm, thigh, and leg) with respect to height and increased body mass index. In some forms of skeletal dysplasias and in particular in SHOX gene anomalies that have many characteristics superimposable to idiopathic short stature, only an accurate auxo-anthropometric and dysmorphologic evaluation enable us to propose, fairly accurately, the subjects for the gene study.
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Antropometría/métodos , Enfermedades del Desarrollo Óseo/patología , Fenotipo , Enfermedades del Desarrollo Óseo/genética , Niño , Preescolar , Enfermedades Carenciales/genética , Enfermedades Carenciales/metabolismo , Enfermedades Carenciales/patología , Femenino , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Masculino , Mutación/genética , Proteína de la Caja Homeótica de Baja EstaturaRESUMEN
In this study, we investigated molecular mechanisms underlying low susceptibility to apoptosis induced by the nucleoside analog azidothymidine (AZT) and the role of nuclear factor-κB (NF-κB) activation in these phenomena. A preliminary screening in different cell lines indicated U937 monocytic cell line as suitable to this purpose. Treatment of U937 cells even with suprapharmacological concentrations of AZT induced only moderate levels of apoptosis. Surprisingly, SuperArray analysis showed that AZT induced the transcriptional activity of both pro- and anti-apoptotic genes. Interestingly, moreover, several genes upregulated by AZT were NF-κB related. In fact, AZT, after an initial inhibition of NF-κB activation with respect to control, induced a transient, but consistent, increase in NF-κB-binding activity. Inhibition of NF-κB activation in U937 cells, stably transfected with a dominant-negative IκBα or by pharmacological treatment, sensitized them to apoptosis induced by AZT and impaired the upregulation of anti-apoptotic genes in response to AZT treatment, with respect to control cells. These results indicate that NF-κB activation by AZT has a role in protecting target cells from apoptotic cell death, improving our understanding of the toxicology and the therapeutic usage of this drug.
Asunto(s)
Antimetabolitos/farmacología , Apoptosis , FN-kappa B/metabolismo , Zidovudina/farmacología , Regulación Neoplásica de la Expresión Génica , Humanos , FN-kappa B/antagonistas & inhibidores , Análisis de Secuencia por Matrices de Oligonucleótidos , Células U937RESUMEN
Melanoma development is a multi-step process arising from a series of genetic and epigenetic events. Although the sequential stages involved in progression from melanocytes to malignant melanoma are clearly defined, our current understanding of the mechanisms leading to melanoma onset is still incomplete. Growing evidence show that the activation of endogenous retroviral sequences might be involved in transformation of melanocytes as well as in the increased ability of melanoma cells to escape immune surveillance. Here we show that human melanoma cells in vitro undergo a transition from adherent to a more malignant, non-adherent phenotype when exposed to stress conditions. Melanoma-derived non-adherent cells are characterized by an increased proliferative potential and a decreased expression of both HLA class I molecules and Melan-A/MART-1 antigen, similarly to highly malignant cells. These phenotypic and functional modifications are accompanied by the activation of human endogenous retrovirus K expression (HERV-K) and massive production of viral-like particles. Down-regulation of HERV-K expression by RNA interference prevents the transition from the adherent to the non-adherent growth phenotype in low serum. These results implicate HERV-K in at least some critical steps of melanoma progression.
Asunto(s)
Transformación Celular Viral , Retrovirus Endógenos/fisiología , Melanoma/virología , Activación Viral/fisiología , Células CACO-2 , Proliferación Celular , Transformación Celular Viral/genética , Células Cultivadas , Células Clonales/virología , Progresión de la Enfermedad , Retrovirus Endógenos/genética , Humanos , Células Jurkat , Células K562 , Melanocitos/patología , Melanocitos/ultraestructura , Melanocitos/virología , Melanoma/etiología , Melanoma/genética , Melanoma/patología , Modelos Biológicos , ARN Viral/aislamiento & purificación , Virión/crecimiento & desarrollo , Activación Viral/genéticaAsunto(s)
Inestabilidad Genómica , Hepatitis C/complicaciones , Linfoma no Hodgkin/genética , Adulto , Anciano , Anciano de 80 o más Años , Aberraciones Cromosómicas , Femenino , Humanos , Hibridación Fluorescente in Situ , Linfoma no Hodgkin/virología , Masculino , Persona de Mediana Edad , Hibridación de Ácido NucleicoAsunto(s)
Fusión Génica , Síndrome Hipereosinofílico/genética , ARN Mensajero/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Tropomiosina/genética , Cromosomas Humanos Par 1 , Cromosomas Humanos Par 10 , Cromosomas Humanos Par 5 , Enfermedad Crónica , Cartilla de ADN , Humanos , Síndrome Hipereosinofílico/patología , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Neoplasias de la Tiroides/genéticaRESUMEN
Fluorescence in situ hybridization and comparative genomic hybridization characterized 6p rearrangements in eight primary and in 10 secondary myeloid disorders (including one patient with Fanconi anemia) and found different molecular lesions in each group. In primary disorders, 6p abnormalities, isolated in six patients, were highly heterogeneous with different breakpoints along the 6p arm. Reciprocal translocations were found in seven. In the 10 patients with secondary acute myeloid leukemia/myelodysplastic syndrome (AML/MDS), the short arm of chromosome 6 was involved in unbalanced translocations in 7. The other three patients showed full or partial trisomy of the 6p arm, that is, i(6)(p10) (one patient) and dup(6)(p) (two patients). In 5/7 patients with unbalanced translocations, DNA sequences were overrepresented at band 6p21 as either cryptic duplications (three patients) or cryptic low-copy gains (two patients). In the eight patients with cytogenetic or cryptic 6p gains, we identified a common overrepresented region extending for 5-6 megabases from the TNF gene to the ETV-7 gene. 6p abnormalities were isolated karyotype changes in four patients. Consequently, in secondary AML/MDS, we hypothesize that 6p gains are major pathogenetic events arising from acquired and/or congenital genomic instability.
Asunto(s)
Cromosomas Humanos Par 6/genética , Leucemia Mieloide/genética , Síndromes Mielodisplásicos/genética , Neoplasias Primarias Secundarias/genética , Translocación Genética/genética , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Análisis Citogenético , Femenino , Humanos , Hibridación Fluorescente in Situ , Leucemia Mieloide/diagnóstico , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/diagnóstico , Neoplasias Primarias Secundarias/diagnóstico , Sensibilidad y EspecificidadRESUMEN
The authors describe the case of an Italian male aged 19 years who came to their observation for severe limping with reduction in hip movement and spondyloepiphyseal radiographic modifications of an osteochondrodysplastic origin. The studies carried out led to a diagnosis of spondyloepiphyseal dysplasia tarda (SEDT).
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Osteocondrodisplasias , Adulto , Diagnóstico Diferencial , Pie/diagnóstico por imagen , Articulación de la Cadera/diagnóstico por imagen , Humanos , Masculino , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/diagnóstico por imagen , Radiografía , Columna Vertebral/diagnóstico por imagenAsunto(s)
Transformación Celular Neoplásica/patología , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Neoplasias Primarias Secundarias/etiología , Linaje de la Célula/genética , Linaje de la Célula/inmunología , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/inmunología , Células Clonales/patología , Análisis Citogenético , Humanos , Inmunofenotipificación , Leucemia Linfocítica Crónica de Células B/etiología , Leucemia Mielógena Crónica BCR-ABL Positiva/etiología , Linfocitos/patología , Persona de Mediana Edad , Células Mieloides/patología , Neoplasias Primarias Secundarias/patologíaRESUMEN
In the present transectional study, Fas ligand (Fas-L) levels, either in membrane or in soluble form, in cells from multiple sclerosis (MS) patients were investigated. Expression of Fas was evaluated after PHA stimulation of peripheral blood mononuclear cells from MS patients with relapsing-remitting or secondary-progressive disease, and in healthy donors. There was statistically significant decreased expression (p = 0.001), as well as release of Fas-L, (p = 0.045) in lymphocytes from MS patients, in comparison with healthy donors. Moreover, levels of Fas-L production were inversely correlated with the EDSS scores of patients in an highly significant way. Impairment of Fas-L release in stimulated PBMC from MS patients might influence the ability to eliminate autoreactive clones in vivo.
Asunto(s)
Linfocitos/metabolismo , Glicoproteínas de Membrana/biosíntesis , Esclerosis Múltiple Crónica Progresiva/inmunología , Esclerosis Múltiple Recurrente-Remitente/inmunología , Adulto , Anciano , Proteína Ligando Fas , Femenino , Humanos , Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Crónica Progresiva/metabolismo , Esclerosis Múltiple Recurrente-Remitente/metabolismo , Fitohemaglutininas/farmacologíaRESUMEN
AIMS/HYPOTHESIS: Using primary cultures of human pancreatic islets, purified human pancreatic beta cells and the mouse beta TC6-F7 cell line, we analysed the expression of nerve growth factor, (NGF/NGF) receptors in beta cells. To investigate whether NGF could sub-serve an autocrine antiapoptotic role in beta cells, we studied the effects of NGF withdrawal using a neutralizing monoclonal anti-NGF antibody. METHODS: The expression of NGF and NGF receptors (gp140(Trk-A) and p75(NTR)) were analysed by RT-PCR and immunofluorescence. Pulse-chase experiments and beta cell/PC12 co-cultures were used to investigate NGF production and secretion from beta cells. Possible apoptosis induced by NGF withdrawal was monitored by phosphatidylserine translocation, nucleosomal formation, DNA laddering and FACS analysis. Involvement of transcription/translation mechanisms were investigated as well as the gp140(Trk-A) required. Finally, signal transduction pathways typically involved in apoptotic mechanisms were analysed by western blot analysis. RESULTS: We show that NGF and both NGF receptors, gp140(Trk-A) and p75(NTR) are expressed in beta cells where NGF is produced and secreted in a biologically active form. NGF-withdrawal induces beta-cell transcription/translation independent apoptosis but mediated by gp140(Trk-A). Analysis of signal transduction pathways revealed that NGF withdrawal inhibits the PI3-K, protein kinase B (AKT), Bad survival pathway and activates c-Jun kinase (JNK) whereas ERKs and p38 mitogen-activated protein kinase (MAPK) are not affected. Moreover, Bcl-XL, but not Bcl-2 protein expression are reduced. CONCLUSION/INTERPRETATION: We suggest that the integrity of the NGF/NGF receptor system and NGF bioavailability participate in controlling beta-cell survival in culture which represents a key issue for improving possibilities for transplantations in the treatment of diabetes.
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Apoptosis , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos , Factor de Crecimiento Nervioso/fisiología , Proteínas Serina-Treonina Quinasas , Animales , Anticuerpos Monoclonales/farmacología , Proteínas Portadoras/metabolismo , Línea Celular , Células Cultivadas , Técnicas de Cocultivo , Fragmentación del ADN , Activación Enzimática , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Expresión Génica , Humanos , MAP Quinasa Quinasa 4 , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Factor de Crecimiento Nervioso/genética , Factor de Crecimiento Nervioso/inmunología , Nucleosomas/ultraestructura , Células PC12 , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilserinas/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/análisis , Ratas , Receptor de Factor de Crecimiento Nervioso , Receptor trkA/análisis , Receptor trkA/genética , Receptores de Factor de Crecimiento Nervioso/análisis , Receptores de Factor de Crecimiento Nervioso/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Proteína Letal Asociada a bcl , Proteína bcl-XRESUMEN
The present study investigated the effect of 3'-azido 3'deoxythymidine (AZT) treatment on in vitro infection of human cord blood mononuclear cells (CBMCs) exposed to HTLV-1 by cocultivation with the MT-2 cell line. Cultures of CBMCs were grown in IL-2 and were either left untreated or were treated with concentrations of AZT ranging from 0.0078 to 32 microM. HTLV-1-infected cultures were monitored at different times of culture by evaluating proliferation activity, cell growth and the presence and expression of HTLV-1 genes. Results showed that untreated cultures infected with HTLV-1 were able to grow for several weeks, while those treated with AZT at 0.03 microM or higher concentrations were limited in their growth capacity. Moreover, the addition of AZT at the moment of infection significantly inhibited cell proliferation in a dose-dependent fashion. In the presence of AZT, detection of proviral DNA and, more remarkably, viral RNA expression were clearly reduced. In addition, treatment with AZT resulted in a noticeable decrease in Tax protein expression. Using treatment with relatively low doses of AZT, effective in exerting an antiviral action, cytotoxicity on CBMCs was not observed, whereas higher doses induced apoptosis in uninfected CBMCs. These data show that CBMCs are protected by AZT against HTLV-1 transmission even at low, non-toxic doses.
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Virus Linfotrópico T Tipo 1 Humano/efectos de los fármacos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/virología , Zidovudina/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Línea Celular , Técnicas de Cocultivo , ADN Viral/análisis , Relación Dosis-Respuesta a Droga , Sangre Fetal , Productos del Gen tax/biosíntesis , Virus Linfotrópico T Tipo 1 Humano/aislamiento & purificación , Virus Linfotrópico T Tipo 1 Humano/fisiología , Humanos , Provirus/aislamiento & purificación , ARN Viral/análisis , Replicación Viral/efectos de los fármacosAsunto(s)
Apoptosis , Infecciones por VIH/virología , VIH-1/crecimiento & desarrollo , ARN Viral/sangre , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Estudios de Cohortes , Estudios de Seguimiento , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/genética , Humanos , Estudios Longitudinales , Carga ViralAsunto(s)
Neoplasias de la Mama/patología , Leucemia Mieloide/inducido químicamente , Neoplasias Primarias Secundarias/inducido químicamente , Proteínas de Fusión Oncogénica/genética , Factores de Transcripción/genética , Enfermedad Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Neoplasias de la Mama/tratamiento farmacológico , Cromosomas Humanos Par 16 , Cromosomas Humanos Par 21 , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Femenino , Humanos , Persona de Mediana Edad , Translocación GenéticaRESUMEN
We report on a case of acute myeloid leukemia in a 17-year old boy affected by Shwachman Diamond syndrome (SDS). Conventional cytogenetics at diagnosis revealed an abnormal clone with complex karyotypic changes including typical myeloid aberrations, such as monosomy 5, tetrasomy of chromosome 8, trisomy 9, and deletion of the short arm of chromosome 12. The boy was treated with conventional chemotherapy and reached complete remission of leukemia, confirmed by cytogenetics and fluorescence in situ hybridization. Nevertheless he failed to regenerate normal marrow cellularity and blood cell count. Cytogenetic information on hematologic malignancies in SDS patients are discussed.
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Análisis Citogenético , Leucemia Mieloide/genética , Síndromes Mielodisplásicos/genética , Anomalías Múltiples/genética , Enfermedad Aguda , Adolescente , Adulto , Células de la Médula Ósea/patología , Células de la Médula Ósea/ultraestructura , Niño , Preescolar , Aberraciones Cromosómicas , Insuficiencia Pancreática Exocrina/complicaciones , Femenino , Humanos , Leucemia Mieloide/etiología , Masculino , Síndromes Mielodisplásicos/complicaciones , SíndromeRESUMEN
CDC6 is conserved during evolution and is essential and limiting for the initiation of eukaryotic DNA replication. Human CDC6 activity is regulated by periodic transcription and CDK-regulated subcellular localization. Here, we show that, in addition to being absent from nonproliferating cells, CDC6 is targeted for ubiquitin-mediated proteolysis by the anaphase promoting complex (APC)/cyclosome in G(1). A combination of point mutations in the destruction box and KEN-box motifs in CDC6 stabilizes the protein in G(1) and in quiescent cells. Furthermore, APC, in association with CDH1, ubiquitinates CDC6 in vitro, and both APC and CDH1 are required and limiting for CDC6 proteolysis in vivo. Although a stable mutant of CDC6 is biologically active, overexpression of this mutant or wild-type CDC6 is not sufficient to induce multiple rounds of DNA replication in the same cell cycle. The APC-CDH1-dependent proteolysis of CDC6 in early G(1) and in quiescent cells suggests that this process is part of a mechanism that ensures the timely licensing of replication origins during G(1).
Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Replicación del ADN , Fase G1 , Ligasas/metabolismo , Proteínas de Saccharomyces cerevisiae , Complejos de Ubiquitina-Proteína Ligasa , Secuencia de Aminoácidos , Ciclosoma-Complejo Promotor de la Anafase , Animales , Northern Blotting , Western Blotting , Ciclo Celular , Proteínas de Ciclo Celular/genética , División Celular , Línea Celular , Cisteína Endopeptidasas/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Datos de Secuencia Molecular , Complejos Multienzimáticos/metabolismo , Fosforilación , Mutación Puntual , Complejo de la Endopetidasa Proteasomal , ARN Mensajero/metabolismo , Origen de Réplica , Ubiquitina-Proteína Ligasas , Ubiquitinas/metabolismoRESUMEN
Thirty-six sex-mismatched transplants were studied using fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) methods. Molecular cytogenetics was performed using interphase FISH with a centromeric probe for chromosome Y, and PCR amplification was performed with a set of VNTR microsatellite loci. In addition, reverse transcriptase-PCR (RT-PCR) for BCR-ABL fusion was used to investigate cases of Philadelphia chromosome (Ph)-positive chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL). Our integrated approach of post-transplant monitoring was helpful in documenting successful transplants and in controlling the size of Ph-positive clones in CML. A striking overlap was found between results from FISH analysis and PCR for polymorphic loci.
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Trasplante de Médula Ósea , Proteínas de Fusión bcr-abl/genética , Trasplante de Células Madre Hematopoyéticas , Hibridación Fluorescente in Situ , Repeticiones de Minisatélite , Cromosoma Y , Adolescente , Adulto , Niño , Femenino , Antígenos HLA , Histocompatibilidad , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
RAR and AML1 transcription factors are found in leukemias as fusion proteins with PML and ETO, respectively. Association of PML-RAR and AML1-ETO with the nuclear corepressor (N-CoR)/histone deacetylase (HDAC) complex is required to block hematopoietic differentiation. We show that PML-RAR and AML1-ETO exist in vivo within high molecular weight (HMW) nuclear complexes, reflecting their oligomeric state. Oligomerization requires PML or ETO coiled-coil regions and is responsible for abnormal recruitment of N-CoR, transcriptional repression, and impaired differentiation of primary hematopoietic precursors. Fusion of RAR to a heterologous oligomerization domain recapitulated the properties of PML-RAR, indicating that oligomerization per se is sufficient to achieve transforming potential. These results show that oligomerization of a transcription factor, imposing an altered interaction with transcriptional coregulators, represents a novel mechanism of oncogenic activation.