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1.
Nutr Metab Cardiovasc Dis ; 25(6): 535-40, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25960399

RESUMEN

BACKGROUND AND AIM: The purpose of this study was to examine the association between physical activity (PA), caloric intake, and Metabolic Syndrome (MetS) in a representative sample of the United States population. METHODS AND RESULTS: Data for 4327 adults from 2007 to 2010 NHANES were analyzed. MetS was defined using both ATPIII and AHA/NHLBI criteria. Weekly moderate and vigorous physical activity (PA) minutes from work, leisure-time, and transportation PA were used to estimate Total Energy Expenditure (TEE) from Basal Metabolic Rate (BMR) using the Harris-Benedict equation. Average total calories (KCAL) from two 24-h dietary recalls were used to compare energy intake and expenditure between subjects with and without MetS. An alpha of 0.05 was used to determine statistical differences. The age adjusted prevalence of MetS was 21.9% (95% CI 20.1-23.6) and 36.8% (34.7-39.0) using ATPIII and AHA/NHLBI criteria, respectively. The estimated population mean for KCAL/TEE was 0.83 (95% CI 0.82-0.84), and the mean for KCAL/BMR was 1.25 (95% CI 1.23-1.27). Subjects without MetS (MetS-) reported 36 ± 13 (ATPIII) and 45 ± 18 (AHA/NHLBI) more daily moderate PA minutes than subjects with MetS (MetS+). At each level of PA, MetS- consumed more calories relative to BMR and TEE than MetS+. For both normal and overweight adults, KCAL/BMR was higher for MetS- than MetS+. For all BMI groups, there were no differences between MetS- and MetS+ with respect to KCAL/TEE. Though MetS+ adults in either MetS criteria were generally less physically active, MetS- adults maintained a higher caloric intake relative to estimated energy needs. CONCLUSIONS: These results suggest energy needs may be distorted in Metabolic Syndrome and increased physical activity may be more protective than reduced caloric intake.


Asunto(s)
Restricción Calórica , Metabolismo Energético , Ejercicio Físico , Síndrome Metabólico/prevención & control , Actividad Motora , Adulto , Factores de Edad , Índice de Masa Corporal , Femenino , Humanos , Masculino , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/epidemiología , Síndrome Metabólico/fisiopatología , Persona de Mediana Edad , Modelos Biológicos , Encuestas Nutricionales , Prevalencia , Factores Protectores , Factores de Riesgo , Conducta Sedentaria , Factores de Tiempo , Estados Unidos/epidemiología , Adulto Joven
3.
Clin Pharmacol Ther ; 81(1): 129-33, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17186012

RESUMEN

Advances in biomedical research over recent decades have substantially raised expectations that the pharmaceutical industry will generate increasing numbers of safe and effective therapies. However, there are warning signs of serious limitations in the industry's ability to effectively translate biomedical research into marketed new therapies. Clinical pharmacologists should be aware of these signals and their potential impact. Here, we discuss a strategy, where clinical pharmacology can play an important role to improve the process of drug development.


Asunto(s)
Investigación Biomédica/organización & administración , Industria Farmacéutica/organización & administración , Farmacología Clínica/organización & administración , United States Food and Drug Administration , Ensayos Clínicos como Asunto , Humanos , Relaciones Interinstitucionales , Estados Unidos
4.
J Histochem Cytochem ; 49(6): 799-800, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11373330

RESUMEN

The origin of the Reed-Sternberg cell of Hodgkin's disease remained clouded in mystery for almost a century after its discovery in 1898. The major obstacle to its understanding is that, unlike other cancers, the malignant cell of Hodgkin's disease is vastly outnumbered by surrounding non-neoplastic cells at approximately 1000:1. We have devised several strategies to isolate Reed-Sternberg T-cells to determine their origin, global gene expression and, ultimately, their pathogenesis. This has increased the number of genes known to be expressed in Reed-Sternberg cells by >100-fold to over 12,000. Approaches such as density gradients, microdissection, and cell sorting help to enrich Reed-Sternberg cells for genomic DNA analysis. However, single-cell micromanipulation of living Reed-Sternberg cells was required to determine the genome-wide gene expression profile of these cells. Combined analysis of single cells and cell lines revealed the expression of 2666 named genes. Further analysis with high-density gene expression microarrays has demonstrated the expression of approximately 12,000 genes by Reed-Sternberg cells. The gene expression profile is that of an aberrant germinal center B-lymphocyte that resists apoptosis through CD40 signaling and NFkappaB activation. Gene expression analysis of Hodgkin's disease is an extreme test case demonstrating the application of high-throughput gene expression studies even to individual cells from clinical samples.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Enfermedad de Hodgkin/etiología , Enfermedad de Hodgkin/genética , Células de Reed-Sternberg/metabolismo , Linfocitos B , Centro Germinal , Enfermedad de Hodgkin/patología , Humanos , Micromanipulación
5.
Omega (Westport) ; 43(1): 7-23, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12542052

RESUMEN

A national membership survey of Hemlock Society USA was conducted by Fox and Kamakahi (1995). Respondents (N=6398) were asked a variety of questions, but in this paper we perform a longitudinal analysis of the characteristics of Hemlock Society USA members. Hemlock Society USA members are divided into three 5-year cohorts: Early Joiners (11 or more years of membership), Middle Joiners (6 to 10 years membership), and Late Joiners (5 or fewer years of membership). Differences between cohorts are examined and extrapolations made regarding Hemlock Society USA and the Right-to-Die Movement. A series of one-way ANOVAs were used with Scheme post-hoc comparisons as heuristic tools for assessing between-cohort differences. Late Joiners are different from earlier members, but are more like other Hemlock Society USA members than the adult U.S. population at large. Hemlock Society USA members are essentially societal "elites" (based on socio-demographic variables) who work in social environments that are decidedly split on the issue of voluntary suicide and euthanasia.


Asunto(s)
Eutanasia Activa Voluntaria/psicología , Política Organizacional , Organizaciones/estadística & datos numéricos , Opinión Pública , Derecho a Morir , Suicidio Asistido/psicología , Humanos , Factores Socioeconómicos , Estados Unidos
6.
Blood ; 96(8): 2841-8, 2000 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11023520

RESUMEN

The malignant Reed-Sternberg cell of Hodgkin disease is an aberrant B cell that persists in an immunolgically mediated inflammatory infiltrate. Despite its nonproductive immunoglobulin genes, the Reed-Sternberg cell avoids the usual apoptotic fate of defective immune cells through an unknown mechanism. A likely candidate is the surface receptor, CD40, consistently expressed by Reed-Sternberg cells, and the first link in the pathway to NF-kappa B activation, the central regulator of cytokine production and apoptosis. CD40 signaling in B lymphocytes coordinates the immune response, including immunoglobulin isotype switch and Fas-mediated apoptosis. CD40-induced NF-kappa B activation is mediated by adapter proteins, the TNF receptor (TNFR)-associated factors (TRAFs), especially TRAFs 2, 3, and 5. Using a Hodgkin cell line, this study demonstrates that CD40 activation of NF-kappa B is mediated by proteolysis of TRAF3. Results further demonstrate that the pathway can be blocked by treatment with pharmacologic doses of a specific protease inhibitor, pepstatin-A, even in the presence of a mutated NF-kappa B inhibitor, I-kappa B alpha. The stability of TRAF3 regulates CD40/NF-kappa B-mediated control of the immune response, which is central to the biologic activity of the Reed-Sternberg cell. Prevention of TRAF3 proteolysis may be an entry point for design of novel pharmaceuticals to treat Hodgkin disease and immune system disorders. (Blood. 2000;96:2841-2848)


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Antineoplásicos/farmacología , Ácido Aspártico Endopeptidasas/fisiología , Antígenos CD40/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Enfermedad de Hodgkin/tratamiento farmacológico , FN-kappa B/antagonistas & inhibidores , Proteínas de Neoplasias/fisiología , Pepstatinas/farmacología , Inhibidores de Proteasas/farmacología , Proteínas/fisiología , Células de Reed-Sternberg/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Citocinas/biosíntesis , Diseño de Fármacos , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/metabolismo , Enfermedad de Hodgkin/patología , Humanos , Interleucina-6/biosíntesis , Interleucina-6/genética , Pepstatinas/uso terapéutico , Estructura Terciaria de Proteína , Proteínas/química , Proteínas/genética , Células de Reed-Sternberg/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Secuencia , Factor 3 Asociado a Receptor de TNF , Células Tumorales Cultivadas/efectos de los fármacos , Receptor fas/fisiología
7.
Blood ; 94(2): 411-6, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10397707

RESUMEN

The malignant Reed-Sternberg cell of Hodgkin's disease, first described a century ago, has resisted in-depth analysis due to its extreme rarity in lymphomatous tissue. To directly study its genome-wide gene expression, approximately 11,000,000 bases (27,518 cDNA sequences) of expressed gene sequence was determined from living single Reed-Sternberg cells, Hodgkin's tissue, and cell lines. This approach increased the number of genes known to be expressed in Hodgkin's disease by 20-fold to 2,666 named genes. The data here indicate that Reed-Sternberg cells from both nodular sclerosing and lymphocyte predominant Hodgkin's disease were derived from an unusual B-cell lineage based on a comparison of their gene expression to approximately 40,000,000 bases (10(5) sequences) of expressed gene sequence from germinal center B cells (GCB) and dendritic cells. The data set of expressed genes, reported here and on the World Wide Web, forms a basis to understand the genes responsible for Hodgkin's disease and develop novel diagnostic markers and therapies. This study of the rare Reed-Sternberg cell, concealed in its heterogenous cellular context, also provides a formidable test case to advance the limit of analysis of differential gene expression to the single disease cell.


Asunto(s)
Linfocitos B/patología , Regulación Neoplásica de la Expresión Génica , Enfermedad de Hodgkin/patología , Proteínas de Neoplasias/análisis , Células de Reed-Sternberg/clasificación , Diferenciación Celular , Linaje de la Célula , ADN Complementario/genética , Células Dendríticas/metabolismo , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Centro Germinal/citología , Enfermedad de Hodgkin/genética , Humanos , Proteínas de Neoplasias/genética , ARN Mensajero/genética , ARN Neoplásico/genética , Células de Reed-Sternberg/metabolismo , Células de Reed-Sternberg/patología , Homología de Secuencia de Ácido Nucleico , Células Tumorales Cultivadas
8.
Am J Clin Pathol ; 111(6): 759-66, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10361511

RESUMEN

Flow cytometric immunophenotypic analysis is critical in diagnosis and classification of acute leukemia and has been used after therapy to monitor for minimal residual disease. However, the presence of normal B-cell precursors, hematogones, particularly in the context of treated pediatric B-cell precursor acute lymphoblastic leukemia (BP-ALL), may confound such evaluation. In this study, the value of more specific genotypic markers (polymerase chain reaction evaluation of 2 antigen receptor genes) was assessed to resolve this issue. Flow cytometric analysis of enriched mononuclear cells revealed 1% to 20% precursor B cells (PBCs), based on expression of 1 or more pan-B cell antigens in addition to CD10, CD34, and terminal deoxynucleotidyl transferase in all 14 patients studied. Inasmuch as this mimicked the immunophenotype of the original leukemic clone, PBCs, in isolation, were considered suspicious for minimal residual disease. However, 11 of the 14 posttherapy specimens (79%) revealed no monoclonally rearranged antigen receptor genes, and 7 of these 11 patients had trackable genotypic markers at presentation. Accordingly, by PCR these 7 patients had complete molecular remission, supported by clinical follow up of 16 to 73 months. Among the remaining 4 patients with PCR-negative disease, 3 continue in remission, confirming the interpretation of false-positive flow cytometric analysis. In conclusion, flow cytometric monitoring of posttherapy bone marrow specimens from patients with BP-ALL may be misleading, if considered in isolation, in falsely suggesting the presence of minimal residual disease. Rather, PCR for antigen receptor gene rearrangements is a valuable and specific tool, helpful in differentiating hematogones from minimal residual disease in patients with treated BP-ALL whose bone marrow harbors increased PBCs.


Asunto(s)
Subgrupos de Linfocitos B/citología , Médula Ósea/patología , Reordenamiento Génico , Genes de Inmunoglobulinas , Genes Codificadores de los Receptores de Linfocitos T , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adolescente , Adulto , Médula Ósea/inmunología , Linfoma de Burkitt/genética , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Linfoma de Burkitt/terapia , Niño , Preescolar , Citometría de Flujo , Humanos , Inmunofenotipificación , Reacción en Cadena de la Polimerasa , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Inducción de Remisión
10.
Am J Surg Pathol ; 22(7): 795-804, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9669342

RESUMEN

Precursor B-lymphoblastic lymphoma (B-LBL) may present as a solitary bone tumor. Fewer than 10 cases with a proven precursor B-cell phenotype have been reported in the English literature. In this report, we describe four cases of B-lymphoblastic lymphoma presenting as a localized intraosseous mass, which clinically and histologically mimicked Ewing's sarcoma. Three tumors occurred in the tibia and one in the humerus. In all four cases, the initial diagnosis was either "Ewing's sarcoma" or "consistent with Ewing's sarcoma." All four patients were female. Three were children and one was an adult; mean age was 12.5 years (range, 4 to 31 years). All had extremity pain without significant constitutional symptoms. In three cases, the tumors were osteolytic on radiographic evaluation, and in one case, osteosclerotic. Immunohistochemical stains on paraffin-embedded tissue showed that the neoplastic cells expressed terminal deoxynucleotidyl transferase, CD43, vimentin, and CD99 (MIC2 gene product) in all cases. Three cases were negative for CD45. CD79a was positive in all four cases studied; however, CD20 (L26) was positive in only two of four cases. CD3 was negative in all cases. Two cases showed focal granular cytoplasmic staining for keratin. Two cases analyzed by polymerase chain reaction (PCR) revealed clonal rearrangement of the immunoglobulin heavy chain (IgH) gene. Follow-up revealed that the three pediatric patients, who received a high-dose multiagent chemotherapy regime for LBL, are disease free at follow-up intervals of more than 1, 11, and 12 years, respectively. The adult patient died two years after diagnosis with disseminated disease. Although rare, B-lymphoblastic lymphoma should be considered in the differential diagnosis of small round cell tumors of bone. A diagnosis of Ewing's sarcoma should be made only after complete immunophenotyping and, if necessary, molecular diagnostic tests to exclude lymphoblastic lymphoma. A limited panel of antibodies can lead to an erroneous diagnosis; B-lymphoblastic lymphoma may be negative for CD45 and CD20 but positive for CD99 and even for keratin, mimicking Ewing's sarcoma. Correct diagnosis is extremely important because LBL usually is curable in the pediatric age group with appropriate therapy.


Asunto(s)
Neoplasias Óseas/diagnóstico , Linfoma de Células B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Sarcoma de Ewing/diagnóstico , Adulto , Antígenos CD/metabolismo , Niño , Preescolar , ADN Nucleotidilexotransferasa/metabolismo , Diagnóstico Diferencial , Resultado Fatal , Femenino , Reordenamiento Génico de Cadena Pesada de Linfocito B/genética , Humanos , Inmunohistoquímica , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Reacción en Cadena de la Polimerasa , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo
11.
J Immunol ; 160(2): 770-7, 1998 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9551912

RESUMEN

TGF-beta1 inhibits the cell cycle progression of many types of cells by arresting them in the G1 phase. This cell cycle arrest has been attributed to the regulatory effects of TGF-beta1 on both the levels and the activities of the G1 cyclins and their kinase partners. The activities of these kinases are negatively regulated by a number of proteins, such as p15INK4b, p21WAF1/Cip1, and p27Kip1, that physically associate with cyclins, cyclin-dependent kinases (Cdk), or cyclin-Cdk complexes. In epithelial cell lines, TGF-beta1 was previously shown to inhibit cell cycle progression through down-regulation of Cdk4 and/or up-regulation of p15INK4b and/or p21WAF1/Cip1. However, TGF-beta1 had little or no effect on the p27Kip1 mRNA and protein levels. In this report, we show that, in contrast to observations in epithelial cell lines, TGF-beta1 increased the p27Kip1 mRNA and protein levels in the murine B cell lines CH31 and WEHI231. This TGF-beta1-mediated induction of p27Kip1 also resulted in an increased association of p27Kip1 with Cdk2 and a decreased Cdk2 kinase activity. In contrast to epithelial cells, however, TGF-beta1 had little or no effect on the Cdk4 and p21WAF1/Cip1 protein levels in these B cells. Finally, although several studies suggested a direct role of p53 in TGF-beta1-mediated cell cycle arrest in epithelial cells, TGF-beta1 inhibited cell cycle progression in CH31 even in the absence of wild-type p53. Taken together, these results suggest that TGF-beta1 induces G1 arrest in B cells primarily through a p53-independent up-regulation of p27Kip1 protein.


Asunto(s)
Linfocitos B/metabolismo , Quinasas CDC2-CDC28 , Proteínas de Ciclo Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Asociadas a Microtúbulos/genética , Proteínas Proto-Oncogénicas , ARN Mensajero/biosíntesis , Factor de Crecimiento Transformador beta/fisiología , Proteínas Supresoras de Tumor , Animales , Linfocitos B/enzimología , Proteínas Portadoras/metabolismo , Quinasa 2 Dependiente de la Ciclina , Quinasa 4 Dependiente de la Ciclina , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Quinasas Ciclina-Dependientes/biosíntesis , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/biosíntesis , Activación Enzimática/efectos de los fármacos , Activación Enzimática/inmunología , Linfoma de Células B , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Serina-Treonina Quinasas/metabolismo , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/fisiología , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/inmunología
12.
Lab Invest ; 78(3): 229-35, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9520936

RESUMEN

In contrast to the non-Hodgkin's lymphomas, little is known regarding the origin, genetics, and function of the Reed-Sternberg cell of Hodgkin's disease. Unlike other cancers, the neoplastic cell of Hodgkin's disease, the Reed-Sternberg cell, is vastly outnumbered by a surrounding intense inflammatory infiltrate. How this rare neoplastic cell originates, persists, and disseminates in a presumably hostile cellular environment has remained a mystery. Understanding the biology of the Reed-Sternberg cell has been impeded by the rarity of the cell in tumor tissue. Herein, we describe how the application of single-cell genetic analysis has revealed a clonal and, possibly, germinal center B-cell origin of the Reed-Sternberg cell. By phenotype and function, Reed-Sternberg cells are highly interactive with their cellular microenvironment through cell-cell adhesion, expression of members of the tumor necrosis factor receptor superfamily, and elaboration of cytokines. Perhaps by their mimicry of immune system cells with antigen-presenting function, Reed-Sternberg cells mediate the unusual clinical and pathologic features of Hodgkin's disease: intense tissue inflammatory infiltrate, fibrosis, and constitutional symptoms.


Asunto(s)
Células de Reed-Sternberg/fisiología , Células Presentadoras de Antígenos/fisiología , Supervivencia Celular/fisiología , Expresión Génica/fisiología , Genes Virales/fisiología , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/genética , Humanos , Receptores del Factor de Necrosis Tumoral/metabolismo , Células de Reed-Sternberg/metabolismo
13.
Blood ; 91(7): 2443-51, 1998 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9516144

RESUMEN

Although Hodgkin's disease is highly responsive to treatments that cause apoptosis, it remains resistant to the physiological mechanisms intended to cause cell death. Presumably, the Reed-Sternberg cell defies endogenous apoptosis, persists, accumulates, and manifests the malignant disorder seen clinically. The Reed-Sternberg cell expresses several members of the tumor necrosis factor receptor superfamily. This family of receptors is involved in both activation and proliferation of cells, as well as either protection from or initiation of apoptosis in cells expressing these surface proteins. Signals from these receptors affect transcription. We reasoned that the activation state and resistance to apoptosis of Reed-Sternberg cells might be attributable to dysregulation of genes controling these processes. To determine gene expression by Reed-Sternberg cells, we developed a method of micromanipulation, global reverse transcription, and the reverse transcription-polymerase chain reaction and applied it to 51 single Reed-Sternberg cells and their variants from six cases of Hodgkin's disease. This report analyzes the gene expression of bcl-xs, bcl-xl, bax-alpha, bax-beta, fadd, fas, fas ligand (fas L), ice, TNF-alpha, TNF-beta, TNFR1, TNFR2, TRAF1, TRAF2, TRAF3, cIAP2, and tradd at the level of mRNA in the single Reed-Sternberg cells and their variants. The findings here suggest a molecular mechanism for the activated state and in vivo survival occurring in untreated Reed-Sternberg cells of Hodgkin's disease.


Asunto(s)
Apoptosis/genética , Regulación Neoplásica de la Expresión Génica , Enfermedad de Hodgkin/patología , Células de Reed-Sternberg/patología , ADN Complementario/análisis , Humanos , Reacción en Cadena de la Polimerasa , Transducción de Señal/genética
14.
Am J Surg Pathol ; 21(7): 860-4, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9236844

RESUMEN

Intravascular lymphomatosis is a rare and peculiar subtype of large cell lymphoma. The authors present the pathologic, clinical, and radiologic findings of a patient with intravascular large cell lymphoma coexisting within hemangiomas of the skin. Initially the lymphoma was clinically confined to the hemangiomas and the patient was closely observed for disease progression. Within 10 months the patient developed disseminated lymphoma involving both adrenals. A clinical remission was achieved, but the patient soon relapsed, and despite further chemotherapy he died with disseminated disease 23 months after the initial diagnosis. This report presents the only known case of an intravascular large cell lymphoma coexisting within a vascular lesion and highlights the potential aggressive nature of intravascular lymphomas.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/patología , Hemangioma/patología , Linfoma de Células B Grandes Difuso/patología , Neoplasias Primarias Múltiples/patología , Neoplasias Cutáneas/patología , Anciano , Antígenos CD20/análisis , Biomarcadores de Tumor/análisis , Resultado Fatal , Humanos , Antígenos Comunes de Leucocito/análisis , Masculino
15.
Hematopathol Mol Hematol ; 11(1): 19-28, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9439977

RESUMEN

Nonrandom use of immunoglobulin variable (V) gene segments is a feature of some B-cell neoplasms, possibly as a consequence of antigen selection. In Hodgkin's disease, the primary tissues, cell lines, and even single Reed-Sternberg cells can carry immunoglobulin gene rearrangements. Here, we examined the immunoglobulin heavy-chain genes of a well-characterized Hodgkin's-derived cell line, L428, and found a hypermutated VH32 gene involving a conventional V(N)D(N)J4-C gamma 4 rearrangement. VH32 is one of two rearranging members of the VH5 family that is also rearranged preferentially in some B-cell neoplasms and familial CLL. Unexpectedly, the closest known rearranged sequence match for the rearranged VH gene of L428 was found in the single Reed-Sternberg cells of lymphocyte-predominance Hodgkin's disease, and is a mutated VH251, the only other rearranging member of the VH5 family. Assuming random usage of the human VH pool, the chance of coincident VH5 family gene rearrangement in the two cases of Hodgkin's disease is only about 10(-3). Biased use of VH genes suggests a B-cell target that is either selected by antigen or vulnerable to transformation at an early antigen-independent, developmental stage. These findings raise the question whether similar processes operate in Hodgkin's disease.


Asunto(s)
Reordenamiento Génico , Genes de Inmunoglobulinas , Enfermedad de Hodgkin/genética , Región Variable de Inmunoglobulina/genética , Mutación , Secuencia de Bases , Clonación Molecular , Enfermedad de Hodgkin/inmunología , Humanos , Datos de Secuencia Molecular , Células Tumorales Cultivadas
16.
Mod Pathol ; 10(1): 33-7, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9021724

RESUMEN

Intravascular lymphomatosis (IVL) is an extremely rare variant of aggressive non-Hodgkin's lymphoma characterized by confinement of neoplastic lymphocytes within vascular spaces. Although IVL is potentially curable with combination chemotherapy, diagnosis is often delayed, in part owing to the negative bone marrow biopsy specimens that are typical of this disorder. We hypothesized that use of a more sensitive method of analysis might identify small clonal B-cell populations in histologically negative bone marrow biopsy specimens from patients with IVL. With use of a recently described assay for immunoglobulin heavy chain gene rearrangement based on the polymerase chain reaction, we demonstrated clonal B-cell populations in histologically negative marrow specimens from five (100%) of five patients with IVL. None of these specimens demonstrated molecular evidence of the t(14;18) associated with follicular lymphoma, providing no evidence for a common derivation of IVL and follicular lymphoma. In summary, molecular analysis of routine bone marrow biopsy sepcimens from patients in whom the diagnosis of IVL is entertained may facilitate prompt recognition of a lympho-proliferative disorder and thereby permit timely therapeutic intervention. Moreover, these findings suggest that despite histologically negative staging bone marrow biopsy specimens, IVL typically disseminates early in its course, thus arguing against the use of localized therapy in this disorder.


Asunto(s)
Médula Ósea/patología , Linfoma de Células B Grandes Difuso/patología , Neoplasias Vasculares/patología , Anciano , Reordenamiento Génico de Linfocito B/genética , Humanos , Cadenas Pesadas de Inmunoglobulina/análisis , Linfoma de Células B Grandes Difuso/diagnóstico , Masculino , Reacción en Cadena de la Polimerasa , Neoplasias Vasculares/diagnóstico
17.
Leuk Res ; 20(8): 683-91, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8913322

RESUMEN

The thymus is a major site of apoptosis where programmed cell death is involved in the deletion of self-reactive T cells. We have investigated the role of bcl-x in T cells by defining the expression of its two isoforms, bcl-x and bcl-xs, in a series of human thymocyte cell lines and in human T lymphocytes using the ribonuclease protection assay. Bcl-x1 was the predominant isoform expressed in T cell lines and in T lymphocytes, where expression was further enhanced by PMA/ionomycin. This broad expression supports a central role for bcl-x in thymocyte development perhaps through post-transcriptional regulation.


Asunto(s)
Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas Proto-Oncogénicas/metabolismo , Linfocitos T/metabolismo , Apoptosis , Humanos , Inmunofenotipificación , Células Tumorales Cultivadas , Proteína bcl-X
18.
J Cutan Pathol ; 23(2): 101-8, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8721443

RESUMEN

We reviewed our experience with six T-cell-rich B-cell lymphomas (TRBL) presenting in skin. Immunohistochemical studies were performed on all biopsies. The lymphoid population consisted mainly of CD3 and/or UCHL-1 (CD45RO) positive T cells. 5 to 15% of the lymphoid cells stained for the B-cell marker L26 (CD20). Monoclonality of the B-cell component was demonstrated in all cases, utilizing either light chain restriction (5 cases) or clonal immunoglobulin heavy chain gene rearrangement by polymerase chain reaction (PCR) (2 cases). One case was confirmed to be monoclonal by both techniques. Additionally, no clonal rearrangements of the T-cell receptor gamma gene were observed. There was considerable morphological variety in these cases. In H&E stained sections, the differential diagnosis included pseudolymphoma, peripheral T-cell lymphoma, Hodgkin's disease, Lennert's lymphoma and a MALT lymphoma. A significant component of monoclonal plasma cells was present in 3 of 6 cases, suggesting a possible origin from cutaneous immunocytoma. In fact, one of our cases was a biphasic lymphoma displaying TRBL with a small focus of immunocytoma. We conclude that immunophenotypic analysis is necessary for the diagnosis of TRBL. Pathologists should be aware of this type of cutaneous B-cell lymphoma to avoid misinterpretation as a pseudolymphoma.


Asunto(s)
Linfoma de Células B/patología , Neoplasias Cutáneas/patología , Linfocitos T/patología , Adulto , Anciano , Anciano de 80 o más Años , Complejo CD3/análisis , Femenino , Humanos , Inmunohistoquímica , Inmunofenotipificación , Antígenos Comunes de Leucocito/análisis , Masculino , Persona de Mediana Edad
19.
Blood ; 87(3): 999-1005, 1996 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-8562972

RESUMEN

GATA-1 protein is thought to be a positive regulator of erythroid differentiation. However, ectopic expression of a conditional GATA-2/estrogen receptor chimera was shown to inhibit erythroid differentiation in a hormone-dependent manner, suggesting the negative regulation of erythroid differentiation by GATA-2 protein. Accordingly, we reasoned that the quantitative balance of GATA-1 and GATA-2 protein might affect erythroid differentiation. In this report, we performed specific and quantitative measurements of GATA-1 and GATA-2 protein in a new erythroid cell line, SAM-1, after treatment with 12-O-tetradecanoylphorbol 13-acetate (TPA). On the basis of these measurements, we show that TPA-induced arrest of erythroid differentiation is coupled with the upregulation of GATA-2 protein, as well as the downregulation of GATA-1 protein. Our results suggest that it is the precise quantitative balance of GATA-1 and GATA-2 protein that regulates erythroid differentiation.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Células Precursoras Eritroides/efectos de los fármacos , Eritropoyesis/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Factores de Transcripción/biosíntesis , Antígenos de Diferenciación/biosíntesis , Antígenos de Diferenciación/genética , Biomarcadores , Crisis Blástica/patología , Diferenciación Celular/efectos de los fármacos , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Factores de Unión al ADN Específico de las Células Eritroides , Factor de Transcripción GATA2 , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Megacariocitos/citología , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Células Tumorales Cultivadas
20.
J Cell Biochem Suppl ; 25: 165-71, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9027614

RESUMEN

Most hematopoietic malignancies are widely disseminated even in their "early" stages and often do not have a well-defined localized phase. This makes them less amenable to conventional early screening methods such as imaging and observation. Furthermore, the staging systems for lymphomas are not particularly useful prognostically, with the possible exception of Hodgkin's disease. However, as currently compared with solid tumors, the extensively detailed understanding of the acquired (somatic) genetic lesions in leukemias and lymphomas provide useful molecular biomarkers for early detection. Moreover, well described high risk groups have been identified. These include individuals who are immunosuppressed, for example, iatrogenically following organ transplantation or those with AIDS. Also at high risk are patients treated with certain chemotherapeutic agents who are at risk for the development of acute non-lymphoblastic leukemia. Accordingly, these clinical settings might prove to be good models for evaluating molecular cancer risk markers and the possible introduction of chemoprevention. Here, we outline the biological basis for the application of biomarkers for the early detection of hematological neoplasia. These concepts may provide the stage for the creation of chemoprevention studies in leukemia and lymphoma.


Asunto(s)
Biomarcadores de Tumor/análisis , Linfoma no Hodgkin/genética , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/genética , Síndrome de Inmunodeficiencia Adquirida/inmunología , Linfocitos B/química , Quimioprevención , Contaminantes Ambientales/efectos adversos , Pruebas Genéticas , Infecciones por HTLV-I/complicaciones , Infecciones por Helicobacter/complicaciones , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Síndromes de Inmunodeficiencia/genética , Linfoma no Hodgkin/etiología , Trastornos Linfoproliferativos/etiología , Trastornos Linfoproliferativos/genética , Masculino , Trasplante de Órganos/efectos adversos , Reacción en Cadena de la Polimerasa , Factores de Riesgo
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