RESUMEN
BACKGROUND: B cells are potential sites for latency and reactivation of the human neurotropic JC polyomavirus (JCV). We investigated JCV and Epstein-Barr virus (EBV) status in peripheral blood lymphocytes (PBL) from 74 Hodgkin's lymphoma (HL) and 91 B-cell non-Hodgkin's lymphoma (B-NHL) patients. PATIENTS AND METHODS: JCV and EBV DNA were assessed by PCR, and FISH technique was used to localize viral infection and to estimate chromosomal instability (rogue cells, 'chromosomal aberrations') throughout evolution. The influence of viral infection and chromosomal instability on freedom from progression (FFP) was investigated in HL patients. RESULTS: PCR product sequencing of PBL identified JCV in 42 (57%) circulating lymphocytes of HL patients. FISH analysis revealed that the presence of cells with a high JCV genome copy number--associated to the presence of rogue cells and 'higher frequency of chromosomal aberrations'--increased from 15% before treatment to 52% (P < 10(-5)) after. The co-activation of JCV and EBV was independent of known prognostic parameters and associated with a shorter FFP (JCV and EBV co-activation P < 0.001, rogue cells P < 0.002). CONCLUSION: In HL, JCV activation and chromosomal instability have been identified in PBL and associated with a poorer prognosis, especially in EBV+.
Asunto(s)
Inestabilidad Cromosómica , Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/genética , Virus JC/fisiología , Linfocitos/metabolismo , Infecciones por Polyomavirus/genética , Infecciones Tumorales por Virus/genética , Adolescente , Adulto , Anciano , Secuencia de Bases , Inestabilidad Cromosómica/genética , Inestabilidad Cromosómica/fisiología , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/epidemiología , Infecciones por Virus de Epstein-Barr/genética , Femenino , Herpesvirus Humano 4/fisiología , Enfermedad de Hodgkin/sangre , Enfermedad de Hodgkin/complicaciones , Humanos , Linfocitos/patología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Infecciones por Polyomavirus/sangre , Infecciones por Polyomavirus/complicaciones , Infecciones por Polyomavirus/epidemiología , Prevalencia , Pronóstico , Estudios Retrospectivos , Infecciones Tumorales por Virus/sangre , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/epidemiología , Adulto JovenRESUMEN
The expression and function of CD95 and CD40 were investigated in malignant cells from EBV-positive undifferentiated nasopharyngeal carcinomas (NPCs). Large amounts of CD95 and CD40 expression were detected in 15 of 16 EBV-positive NPC specimens. In contrast, CD95 was not detected in two biopsies from patients with EBV-negative differentiated NPCs. We tested whether the CD95 apoptotic pathway was functional in NPC cells by treating two EBV-positive NPC tumor lines in vitro with a CD95 agonist. In both cases, NPC cells were extremely susceptible to CD95-mediated apoptosis, despite strong constitutive expression of Bcl-x. Combined CD40 and CD95 stimulation was used to investigate the possible anti-apoptotic activity mediated by CD40. The CD40 receptor was activated by incubating NPC cells with murine L cells producing CD154, the CD40 ligand. This treatment resulted in a strong inhibition of CD95-related cytotoxicity. Such an anti-apoptotic effect of CD40 is well known for B lymphocytes, but has not previously been reported for epithelial cells. These data suggest that NPC tumor-infiltrating lymphocytes, which often produce the CD40 ligand in situ, may increase the survival of malignant cells, thereby enhancing tumor growth in patients.
Asunto(s)
Apoptosis , Antígenos CD40/fisiología , Herpesvirus Humano 4/aislamiento & purificación , Neoplasias Nasofaríngeas/patología , Receptor fas/fisiología , Adolescente , Antígenos CD40/análisis , Supervivencia Celular , Femenino , Humanos , Neoplasias Nasofaríngeas/virología , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Células Tumorales Cultivadas , Proteína bcl-X , Receptor fas/análisisRESUMEN
Plasma accelerators driven by particle beams are a very promising future accelerator technology as they can sustain high accelerating fields over long distances with high energy efficiency. They rely on the excitation of a plasma wave in the wake of a drive beam. To generate the plasma, a neutral gas can be field-ionized by the head of the drive beam, in which case the distance of acceleration and energy gain can be strongly limited by head erosion. Here we overcome this limit and demonstrate that electrons in the tail of a drive beam can be accelerated by up to 27 GeV in a high-ionization-potential gas (argon), boosting their initial 20.35 GeV energy by 130%. Particle-in-cell simulations show that the argon plasma is sustaining very high electric fields, of â¼150 GV m(-1), over â¼20 cm. The results open new possibilities for the design of particle beam drivers and plasma sources.
RESUMEN
The cytotoxicities of free cyanoacrylic nanoparticles, free Adriamycin, Adriamycin-loaded nanoparticles and a mixture of Adriamycin and nanoparticles are compared in cancer cell cultures. Increased cytotoxicity was observed in the sensitive (DC3F) subline when Adriamycin was in particulate form rather than free. In the derived pleiotropic resistant subline (DC3F AD/AZA), sensitivity to Adriamycin was completely restored with the conjugate. Addition of verapamil or amiodarone allowed an enhancement of efficiency of tenfold for free Adriamycin and between two- and fourfold for its conjugate form. Vectorization by nanoparticles and pharmacological modulation of cell membrane can act in synergy in synergy to overcome the resistance to Adriamycin in vitro.
Asunto(s)
Cianoacrilatos , Doxorrubicina/toxicidad , Amiodarona/farmacología , Animales , Cricetinae , Cricetulus , Dactinomicina , Portadores de Fármacos , Resistencia a Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Biosíntesis de Proteínas , Células Tumorales Cultivadas , Verapamilo/farmacologíaRESUMEN
Mantle cell lymphoma (MCL) is characterized by the t(11;14)(q13;q32), which is associated with cyclin D1 hyperexpression and a poor prognosis. MCL cases have been shown to progress to a more aggressive disease but the molecular events responsible of this phenomenon have not been determined. We have established two cell lines from the pleural effusions of two patients with MCL that we have used for further cytogenetic characterization to better define the incidence and nature of secondary chromosome abnormalities using multicolor fluorescence in situ hybridization, whole chromosome paint, and specific probes. Both cell lines grew independently without growth factors. Using CCND1/IGH-specific probes, patient UPN1 was found to have a masked t(11;14). Numerous and complex chromosomal abnormalities were found in both cell lines affecting chromosomes 2, 8, 13, 18, 22, X, and Y. These abnormalities included 8p losses, suggesting the presence of an anti-oncogene in this region, rearrangements of 8q24, MYC gene, and translocations involving 8, X, and Y chromosomes, which might be significant in the pathogenesis of MCL progression. The use of the cell lines (UPN1) allowed us to generate a mouse model of human MCL, mimicking a disseminated lymphoma and leading to the death of the animals in 4 weeks. This blastoid MCL model could be of major interest to determine molecular events involved in MCL progression, allowing isolation of involved genes and their functional characterization, and to study the effects of new chemotherapy regimens in mouse models.
Asunto(s)
Aberraciones Cromosómicas , Modelos Animales de Enfermedad , Linfoma de Células del Manto/genética , Translocación Genética , Animales , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 14 , Humanos , Hibridación Fluorescente in Situ , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Trasplante de Neoplasias , Células Tumorales CultivadasAsunto(s)
Antineoplásicos/uso terapéutico , Aberraciones Cromosómicas , Resistencia a Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Cromosoma Filadelfia , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Benzamidas , Humanos , Mesilato de Imatinib , CariotipificaciónRESUMEN
Undifferentiated nasopharyngeal carcinoma (NPC) was originally referred to as "lymphoepithelial carcinoma." Two main cell types are constantly associated within these tumors: the malignant epithelial cells which harbor the Epstein-Barr virus (EBV) genome, and the nonmalignant lymphocytes mostly of the T lineage. Three characteristic features of malignant NPC cells might explain T cell migration within NPC tumor tissue: HLA class II molecule expression, IL-1 production, and presence of EBV antigens. Homogeneous suspensions of malignant NPC cells were derived from a nude-mouse transplantable tumor in order to specify the status of HLA class II molecules in these tumors. These suspensions were stained for HLA class II antigens and analyzed by flow cytometry in comparison with other carcinoma cell lines. Three characteristics of transplantable malignant NPC cells were demonstrated: constitutive and coordinate expression of DR, DP, and DQ molecules, and concomitant expression with the CDw40 antigen ("B lymphocyte carcinoma cross-reacting antigen").
Asunto(s)
Antígenos de Histocompatibilidad Clase II/biosíntesis , Neoplasias Nasofaríngeas/inmunología , Linfocitos T/inmunología , Infecciones Tumorales por Virus , Adolescente , Antígenos de Diferenciación de Linfocitos T/análisis , Antígenos Virales/análisis , Línea Celular , Femenino , Citometría de Flujo , Antígenos HLA/análisis , Herpesvirus Humano 4 , Humanos , Interleucina-1/biosíntesis , Neoplasias Nasofaríngeas/microbiologíaRESUMEN
Comparison between membrane markers and enzyme markers was made in 74 cases of non-Hodgkin's malignant lymphomas and a good correlation appears between both methods in order to distinct lymphomas into T and B origin. Enzyme markers are reliable and provide quickly made and easily interpretable documents. As far as T-lymphomas are concerned, three hydrolases namely acid phosphates e, acid esterase and B-glucuronidase give the same good results. As for B-lymphomas, a specific enzyme marker has to be found. Furthermore, typing of malignant lymphomas by enzymatic and/or immunologic methods appears to be quite better than from morphologic features such as convoluted or cleaved nuclei for example.
Asunto(s)
Linfoma/diagnóstico , Fosfatasa Ácida/metabolismo , Fosfatasa Alcalina/metabolismo , Linfocitos B/inmunología , Esterasas/metabolismo , Glucuronidasa/metabolismo , Humanos , Linfoma/enzimología , Linfoma/inmunología , Métodos , Linfocitos T/inmunologíaRESUMEN
Using polymerase chain reaction (PCR), we confirmed the expression of interleukin-1 alpha (IL-1 alpha) by the human nasopharyngeal carcinoma (NPC) cell line C15 without contribution of either human IL-1 beta or mouse IL-1 alpha in the biological activity previously found in C15. However we showed that IL-1 alpha was not expressed in all NPCs. IL-1 beta and/or tumor necrosis factor (TNF)-alpha genes could also be activated, independently from the number of Epstein Barr Virus (EBV) copies harbored by the cells. Interestingly, the primary tumor C15 showed a profile of TNF-sensitive tumor while C17, C18 and C19 which were derived from metastasis have a typical profile of TNF-resistant cells. Furthermore, the inflammatory cytokines whose genes are classically induced by IL-1 and TNF were found expressed only in C17 and C19 suggesting another level of heterogeneity among NPCs.
Asunto(s)
Citocinas/genética , Expresión Génica , Neoplasias Nasofaríngeas/metabolismo , Animales , Secuencia de Bases , Quimiocina CCL2 , Factores Quimiotácticos/genética , Genes Virales , Herpesvirus Humano 4/genética , Humanos , Interleucina-1/genética , Interleucina-8/genética , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ARN Mensajero/metabolismo , Receptores de Superficie Celular/genética , Receptores del Factor de Necrosis Tumoral , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Latent Membrane Protein 1 (LMP1) is an EBV-transforming protein which is detected both in lymphoblastoid cell lines-resulting from EBV-immortalization in vitro- and in undifferentiated nasopharyngeal carcinoma (NPC), an EBV-associated malignancy of epithelial origin. To better define LMP1 subcellular targets, LMP1 distribution was analyzed in cellular glycosphingolipid-rich complexes (GSL-complexes) derived from epithelial and lymphoid cells. These complexes are obtained by extraction of glycosphingolipid-rich membrane domains (GSL-domains), which are clustering sites for heterotrimeric G-proteins and G-protein-associated receptors. LMP1 concentration was enriched 50-fold in GSL-complexes extracted from a NPC tumor line, C15. High concentrations of LMP1 were also observed in GSL-complexes derived from cultured lymphoid and epithelial cells. These data suggest that association with GSL-domains is an important step in LMP1 trafficking and is probably required for some aspects of its biological activity.
Asunto(s)
Glicoesfingolípidos/metabolismo , Herpesvirus Humano 4/metabolismo , Linfocitos/virología , Proteínas de la Matriz Viral/metabolismo , Animales , Células Epiteliales , Epitelio/virología , Células HeLa , Humanos , Linfocitos/citología , Ratones , Ratones Desnudos , Células Tumorales CultivadasRESUMEN
Latent membrane protein 1 (LMP1) is an Epstein-Barr virus (EBV) protein expressed in EBV-transformed B lymphocytes and in approximately 50% of nasopharyngeal carcinomas (NPCs). LMP1 signaling involves several cellular signaling intermediates, especially TNF receptor-associated factors (TRAFs). We have shown previously that LMP1 is highly concentrated in a cell fraction called glycosphingolipid-rich membrane complexes (GSL complexes). We report here that parallel accumulation of LMP1 and TRAF3, but not TRAF1 or TRADD, was observed in GSL complexes from lymphoblastoid and LMP1-positive NPC cells. In contrast, TRAF3 was not concentrated in GSL complexes from LMP1-negative cells. Binding of LMP1 and TRAF3 in GSL complexes was demonstrated in lymphoblastoid and NPC cells, by co-immunoprecipitation with both anti-LMP1 and anti-TRAF3 antibodies.
Asunto(s)
Linfoma de Burkitt/metabolismo , Glicoesfingolípidos/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas/metabolismo , Proteínas de la Matriz Viral/metabolismo , Animales , Biopsia , Linfoma de Burkitt/química , Linfoma de Burkitt/patología , Centrifugación por Gradiente de Densidad , Glicoesfingolípidos/aislamiento & purificación , Herpesvirus Humano 4/genética , Humanos , Ratones , Ratones Desnudos , Neoplasias Nasofaríngeas/química , Neoplasias Nasofaríngeas/patología , Proteínas/genética , Proteínas/aislamiento & purificación , Receptores del Factor de Necrosis Tumoral/fisiología , Factor 3 Asociado a Receptor de TNF , Trasplante Heterólogo , Células Tumorales Cultivadas , Proteínas de la Matriz Viral/genética , Proteínas de la Matriz Viral/aislamiento & purificaciónRESUMEN
The Epstein-Barr virus (EBV) is a ubiquitous Herpes virus which causes infectious mononucleosis and is associated with such different neoplasms as Burkitt's lymphoma and nasopharyngeal carcinoma. EBV latently infects its target cells; nevertheless, evidence of viral replication in NPC tumours has been uncovered. Among the EBV transactivators, the ZEBRA protein plays a crucial role in switching the virus from a latent to a productive mode. ZEBRA protein was produced using a eukaryotic expression vector: the open reading frame containing the BZFLI cDNA has previously been inserted down-stream from the adenovirus major late promoter leading to expression of a 38-kDa nuclear protein. We performed serological studies by employing ZEBRA protein expressed in human cells for immunofluorescence and Western-blot assays. We were able to detect IgG anti-ZEBRA antibodies (IgG/ZEBRA) in 87% of NPC patients. These antibodies were absent in control sera; IgG/ZEBRA antibodies can be proposed as a useful marker for diagnosis of NPC tumors.
Asunto(s)
Anticuerpos Antivirales/análisis , Proteínas de Unión al ADN/inmunología , Herpesvirus Humano 4/inmunología , Inmunoglobulina G/análisis , Neoplasias Nasofaríngeas/microbiología , Transactivadores/inmunología , Proteínas Virales , Formación de Anticuerpos , Antígenos Virales/inmunología , Línea Celular , Antígenos Nucleares del Virus de Epstein-Barr , Humanos , Neoplasias Nasofaríngeas/inmunología , Neoplasias/inmunología , Neoplasias/microbiología , Valores de ReferenciaRESUMEN
We studied the lymphomatous cells of 39 children presenting with the classical features of malignant lymphoma. Twenty-two had T lymphoblasts. We could classify these patients into three subsets: The T lymphoblasts from children group 1 displayed antigen(s) shared by a thymocyte subpopulation, had terminal deoxynucleotidyl transferase (TDT), but no affinity for peanut agglutinin (PNA). The T lymphoblasts from children group 2 lacked the thymocyte antigen(s), had no TDT, but showed affinity for PNA. The T lymphoblasts from children group 3 displayed mature T-cell antigens, had no TDT, and no affinity for PNA. Children from the three groups were similar in terms of clinical presentation, age and sex distribution, and cell morphology; however patients from the three groups might have a different prognosis. Fourteen children had B lymphoblasts that, in half of the cases, had affinity for Helix pomatia agglutinin. Three patients had lymphoblasts lacking specific marker. Two of them had cells displaying an antigen found on common acute lymphoblastic leukemia cells and had TDT.
Asunto(s)
Transformación Celular Neoplásica , Linfoma/sangre , Linfocitos T/clasificación , Adolescente , Suero Antilinfocítico/farmacología , Linfocitos B/clasificación , Niño , Preescolar , Epítopos , Femenino , Humanos , Linfoma/tratamiento farmacológico , Masculino , Fenotipo , Receptores de Antígenos de Linfocitos B , Formación de Roseta , Linfocitos T/inmunologíaRESUMEN
Three transplantable nasopharyngeal carcinoma (NPC) tumors, designated C15, C17 and C18, have been obtained and characterized. C15, derived from a primary NPC tumor, has been propagated in nude mice for 30 passages. C17 and C18, derived from metastatic NPC tissue, have been passaged 10 times. Desmosomes, present in every case, provided confirmation of the epithelial origin of all 3 tumors. The Epstein-Barr virus (EBV) genome is contained in C15, C18 and C17 tumor cells with 30, 12 and 3 copies, respectively. The Epstein-Barr virus nuclear antigen (EBNA) was stained by the classical anti-complement immunofluorescence (ACIF) technique. Fluorescence intensity was strong in C15, moderate in C18, and hardly detectable in C17 cells. No expression of the EA and VCA antigens was detected. Flow cytometry analysis performed on monocellular suspensions showed the absence of detectable CR2 molecules (the EBV receptor on B lymphocytes) in all 3 tumors, and the constitutive expression of HLA class-II antigens in C15 and C17 cells. IL-1 activity was demonstrated in the supernatant of C15 and C17 cells cultivated in vitro for 3 days. These data confirm that the constitutive synthesis of MHC class-II molecules and the release of IL-1-like activities are frequent features of NPC cells. These characteristics could be of importance in relation with the T-cell infiltrate found in NPC primary tumors.
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Antígenos Virales/aislamiento & purificación , Carcinoma/patología , Neoplasias Nasofaríngeas/patología , Adolescente , Animales , Antígenos de Diferenciación de Linfocitos B/análisis , Antígenos de Superficie/análisis , Antígenos Virales/análisis , Carcinoma/inmunología , Carcinoma/microbiología , ADN Viral/análisis , Antígenos Nucleares del Virus de Epstein-Barr , Femenino , Antígenos HLA-D/análisis , Humanos , Interleucina-1/biosíntesis , Ratones , Neoplasias Nasofaríngeas/inmunología , Neoplasias Nasofaríngeas/microbiología , Trasplante de Neoplasias , Receptores de Complemento/análisis , Receptores de Complemento 3d , Trasplante HeterólogoRESUMEN
Neuroblastoma, the most common solid extracranial neoplasm in children, shows an appreciable variability in clinical evolution. Amplification of the MYCN oncogene in this tumor is detected in 25 to 30% of cases and is associated with poor clinical outcome. In this study, quantitative polymerase chain reaction and fluorescence in situ hybridization were used to determine MYCN amplification status in 46 neuroblastoma tumors. MYCN amplification was detected in tumors from 11 patients. Fluorescence in situ hybridization revealed the presence of micronuclei containing amplified MYCN sequences in 8 of the 11 tumors. Micronuclei are indicative of spontaneous elimination or loss of amplified sequences by tumor cells. Because the elimination of amplified sequences can be enhanced in vitro by specific drugs such as hydroxyurea, our observations suggest a new therapeutic strategy specifically targeted to cells with amplified genes.
Asunto(s)
Genes myc/genética , Micronúcleos con Defecto Cromosómico/metabolismo , Neuroblastoma/genética , Preescolar , ADN de Neoplasias/genética , Amplificación de Genes , Humanos , Hibridación Fluorescente in Situ , Lactante , Micronúcleos con Defecto Cromosómico/genética , Pruebas de Micronúcleos , Neuroblastoma/patología , Reacción en Cadena de la PolimerasaRESUMEN
Undifferentiated nasopharyngeal carcinoma (NPC) is a remarkable entity among human tumors because of its constant association with the Epstein-Barr virus (EBV). Malignant epithelial cells harbor the EBV genome and often express at least 2 species of latent EBV protein (EBNA1 and LMP1). Despite the massive presence of tumor-infiltrating lymphocytes, NPC cells obviously escape immune surveillance directed to EBV antigens. Previous investigations carried out on EBV-positive Burkitt lymphoma (BL) cells have shown that this fact may be partially accounted for by a lack of expression of ICAM1 (CD54) and LFA3 (CD58). ICAM1 and LFA3 have therefore been investigated in fresh NPC biopsies and transplanted NPCs. With only 1 exception out of 9 cases, NPC cells appear to express high levels of ICAM1 and low levels of LFA3. This is a complete inversion of the pattern observed in normal epithelial cells in vivo. Additional investigations will be required to determine to what extent these characteristics affect T-cell interactions with NPC cells, specially in the process of EBV-antigen recognition.