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1.
Ann Oncol ; 27(2): 306-14, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26598546

RESUMEN

BACKGROUND: ALK-negative anaplastic large cell lymphoma associated with breast implant (i-ALCL) has been recently recognized as a distinct entity. Among 43 830 lymphomas registered in the French Lymphopath network since 2010, 300 breast lymphomas comprising 25 peripheral T-cell lymphomas (PTCL) were reviewed. Among PTCL, ALK-negative ALCL was the most frequent and all of them were associated with breast implants. PATIENTS AND METHODS: Since 2010, all i-ALCL cases were collected from different institutions through Lymphopath. Immuno-morphologic features, molecular data and clinical outcome of 19 i-ALCLs have been retrospectively analyzed. RESULTS: The median age of the patients was 61 years and the median length between breast implant and i-ALCL was 9 years. Most implants were silicone-filled and textured. Implant removal was performed in 17 out of 19 patients with additional treatment based on mostly CHOP or CHOP-like chemotherapy regimens (n = 10/19) or irradiation (n = 1/19). CHOP alone or ABVD following radiation without implant removal have been given in two patients. The two clinical presentations, i.e. effusion and less frequently tumor mass correlated with distinct histopathologic features: in situ i-ALCL (anaplastic cell proliferation confined to the fibrous capsule) and infiltrative i-ALCL (pleomorphic cells massively infiltrating adjacent tissue with eosinophils and sometimes Reed-Sternberg-like cells mimicking Hodgkin lymphoma). Malignant cells were CD30-positive, showed a variable staining for EMA and were ALK negative. Most cases had a cytotoxic T-cell immunophenotype with variable T-cell antigen loss and pSTAT3 nuclear expression. T-cell receptor genes were clonally rearranged in 13 out of 13 tested cases. After 18 months of median follow-up, the 2-year overall survival for in situ and infiltrative i-ALCL was 100% and 52.5%, respectively. CONCLUSIONS: In situ i-ALCLs have an indolent clinical course and generally remain free of disease after implant removal. However, infiltrative i-ALCLs could have a more aggressive clinical course that might require additional therapy to implant removal.


Asunto(s)
Implantes de Mama/efectos adversos , Linfoma Anaplásico de Células Grandes/patología , Linfoma de Células T Periférico/patología , Siliconas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Quinasa de Linfoma Anaplásico , Femenino , Enfermedad de Hodgkin/patología , Humanos , Inmunofenotipificación , Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/inducido químicamente , Linfoma Anaplásico de Células Grandes/mortalidad , Linfoma de Células T Periférico/inducido químicamente , Linfoma de Células T Periférico/mortalidad , Persona de Mediana Edad , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Estudios Retrospectivos , Factor de Transcripción STAT3/metabolismo , Linfocitos T Citotóxicos/inmunología
2.
Ann Oncol ; 23(10): 2687-2695, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22767588

RESUMEN

BACKGROUND: This study explored the efficacy and safety of rituximab as treatment of clinical or molecular residual disease after autologous stem-cell transplantation (ASCT) in follicular lymphoma (FL). PATIENTS AND METHODS: Forty patients with CD20+ FL and clinically (group A, n = 14) or clono-specific PCR-detectable (group B, n = 25) residual disease persisting 3 months after ASCT received rituximab 375 mg/m² once weekly for 4 weeks. RESULTS: Response rate at day 50 was 36% [90% confidence interval (CI) 15-61] in group A (World Health Organization criteria) and 52% (90% CI 34-70) in group B (conversion PCR-undetectable status to undetectable status). The best response rate was 71% [nine complete responses (CRs) and one partial response] in group A and 76% in group B. At 36 months, all 10 responses persisted in group A, whereas 46% of patients in group B still had PCR-undetectable disease. Furthermore, 68% of patients in group B were still in clinical CR. Rituximab after ASCT was safe with few grade 3-4 toxic effects (15% patients), mainly acute reactions and infections. CONCLUSION: Rituximab induced a high rate of durable CRs in patients with clinically detectable disease, as well as durable eradication of PCR-detectable disease in patients with FL after ASCT. Continued molecular responses assessed with a highly sensitive and clono-specific PCR technique were correlated with an excellent disease control.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antineoplásicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Linfoma Folicular/tratamiento farmacológico , Neoplasia Residual , Adolescente , Adulto , Anciano , Humanos , Linfoma Folicular/patología , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Rituximab , Adulto Joven
4.
Leukemia ; 25(12): 1882-90, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21778999

RESUMEN

The anaplastic lymphoma kinase (ALK), tyrosine kinase oncogene is implicated in a wide variety of cancers. In this study we used conditional onco-ALK (NPM-ALK and TPM3-ALK) mouse MEF cell lines (ALK+ fibroblasts) and transgenic models (ALK+ B-lymphoma) to investigate the involvement and regulation of angiogenesis in ALK tumor development. First, we observed that ALK expression leads to downregulation of miR-16 and increased Vascular Endothelial Growth Factor (VEGF) levels. Second, we found that modification of miR-16 levels in TPM3-ALK MEF cells greatly affected VEGF levels. Third, we demonstrated that miR-16 directly interacts with VEGF mRNA at the 3'-untranslated region and that the regulation of VEGF by miR-16 occurs at the translational level. Fourth, we showed that expression of both the ALK oncogene and hypoxia-induced factor 1α (HIF1α) is a prerequisite for miR-16 downregulation. Fifth, in vivo, miR-16 gain resulted in reduced angiogenesis and tumor growth. Finally, we highlighted an inverse correlation between the levels of miR-16 and VEGF in human NPM-ALK+ Anaplastic Large Cell Lymphomas (ALCL). Altogether, our results demonstrate, for the first time, the involvement of angiogenesis in ALK+ ALCL and strongly suggest an important role for hypoxia-miR-16 in regulating VEGF translation.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Hipoxia/metabolismo , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/metabolismo , MicroARNs/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Quinasa de Linfoma Anaplásico , Animales , Northern Blotting , Western Blotting , Estudios de Casos y Controles , Adhesión Celular , Movimiento Celular , Células Cultivadas , Metilación de ADN , Regulación hacia Abajo , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Hipoxia/genética , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Técnicas para Inmunoenzimas , Linfoma Anaplásico de Células Grandes/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/metabolismo , Neovascularización Patológica , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Tirosina Quinasas Receptoras/genética , Factor A de Crecimiento Endotelial Vascular/genética
5.
Blood Cancer J ; 1(6): e21, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22829165

RESUMEN

Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) is a tyrosine kinase oncogene responsible for the pathogenesis of the majority of human ALK-positive lymphomas. We recently reported that it activated the Rac1 GTPase in anaplastic large-cell lymphoma (ALCL), leading to Rac-dependent formation of active invadopodia required for invasiveness. Herein, we went further into the study of this pathway and used the inhibitor of Rac, NSC23766, to validate its potential as a molecular target in ALCL in vitro and in vivo in a xenograft model and in a conditional model of NPM-ALK transgenic mice. Our data demonstrate that Rac regulates important effectors of NPM-ALK-induced transformation such as Erk1/2, p38 and Akt. Moreover, inhibition of Rac signaling abrogates NPM-ALK-elicited disease progression and metastasis in mice, highlighting the potential of small GTPases and their regulators as additional therapic targets in lymphomas.

6.
Bull Cancer ; 97(11): 1347-64, 2010 Nov.
Artículo en Francés | MEDLINE | ID: mdl-21084243

RESUMEN

Numerous molecular abnormalities have been described in lymphomas. They are of diagnostic and prognostic value and are taken into account for the WHO classification of these tumors. They also shed some light on the underlying molecular mechanisms involved in lymphomas. Overall, four types of molecular abnormalities are involved: mutations, translocations, amplifications and deletions of tumor suppressor genes. Several techniques are available to detect these molecular anomalies: conventional cytogenetic analysis, multicolor FISH, CGH array or gene expression profiling using DNA microarrays. In some lymphomas, genetic abnormalities are responsible for the expression of an abnormal protein (e.g. tyrosine-kinase, transcription factor) detectable by immunohistochemistry. In the present review, molecular abnormalities observed in the most frequent B, T or NK cell lymphomas are discussed. In the broad spectrum of diffuse large B-cell lymphomas microarray analysis shows mostly two subgroups of tumors, one with gene expression signature corresponding to germinal center B-cell-like (GCB: CD10+, BCL6 [B-Cell Lymphoma 6]+, centerine+, MUM1-) and a subgroup expressing an activated B-cell-like signature (ABC: CD10-, BCL6-, centerine-, MUM1+). Among other B-cell lymphomas with well characterized molecular abnormalies are follicular lymphoma (BCL2 deregulation), MALT lymphoma (Mucosa Associated Lymphoid Tissue) [API2-MALT1 (mucosa-associated-lymphoid-tissue-lymphoma-translocation-gene1) fusion protein or deregulation BCL10, MALT1, FOXP1. MALT1 transcription factors], mantle cell lymphoma (cycline D1 [CCND1] overexpression) and Burkitt lymphoma (c-Myc expression). Except for ALK (anaplastic lymphoma kinase)-positive anaplastic large cell lymphoma, well characterized molecular anomalies are rare in lymphomas developed from T or NK cells. Peripheral T cell lymphomas not otherwise specified are a heterogeneous group of tumors with frequent but not recurrent molecular abnormalities. Gene profiling analysis shows that the expression of several genes is deregulated including PDGFRA (platelet-derived growth factor receptor) gene, encoding a receptor with tyrosine kinase activity. In angio-immunoblastic T-cell lymphomas molecular abnormalities are found in follicular helper T-cell (TFH) that express some distinctive markers such as CD10, PD-1, CXCR5 and the CXCL13 chemokine. ALK-positive anaplastic large cell lymphoma is a paradigme of T-cell lymphoma since it is associated with an X-ALK oncogenic fusion protein due to a translocation involving ALK gene at 2p23. ALK tyrosine kinase activates downstream pathways (Stat3/5b, Src kinases, PLCγ, PI3 kinase) implicated in lymphomagenesis, proliferation and protection against apoptosis. Specific ALK inhibitors are currently in clinical evaluation. Lastly several lymphomas are associated with infectious agents that play a direct (EB virus, HTLV1) or indirect role (e.g. Helicobacter pylori in MALT lymphoma) in lymphomagenesis.


Asunto(s)
Amplificación de Genes/genética , Genes Supresores de Tumor , Linfoma/genética , Mutación/genética , Translocación Genética/genética , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica/genética , Técnicas Genéticas , Humanos , Linfoma/clasificación , Linfoma/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Linfoma de Células T/genética , Linfoma de Células T/metabolismo , Proteínas de Neoplasias/metabolismo
7.
Oncogene ; 28(29): 2690-6, 2009 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-19503098

RESUMEN

The chimera nucleophosmin-anaplastic lymphoma kinase (NPM-ALK), the tyrosine kinase activity of which is constitutively upregulated, is the causative agent of 75% of the anaplastic large-cell lymphomas (ALCLs). We have demonstrated that NPM-ALK induces the production of reactive oxygen species (ROS) by a pathway involving the arachidonic acid-metabolizing enzymes of the lipoxygenase (LOX) family. The use of the LOX inhibitor nordihydroguaiaretic acid (NDGA) and of the anti-oxidant N-acetylcysteine (NAC) demonstrated that ROS are important in maintaining the ALK kinase active. Consistent with this, NDGA treatment resulted in the inhibition of key pathways, such as Akt, signal transducer and activator of transcription factor 3 (STAT3) and extracellular signal-regulated kinase (ERK), which are involved in NPM-ALK antiapoptotic and pro-mitogenic functions. Conversely, the stress-activated kinase p38, described in some instances as a mediator of apoptosis, was activated. Interestingly, 5-LOX, an isoform involved in many cancers, was found to be activated in NPM-ALK(+) cells. Functional studies have shown that transforming properties, namely proliferation and resistance to apoptosis, were abrogated by treatment with either NDGA or the 5-LOX inhibitor (N-(3-phenoxycinnamyl)-acetohydroxamic acid) (BW A4C). Together, these data point to the ROS/LOX pathway as a potential new target for therapy in NPM-ALK-positive tumors.


Asunto(s)
Araquidonato 5-Lipooxigenasa/metabolismo , Linfoma Anaplásico de Células Grandes/patología , Proteínas Tirosina Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Apoptosis , Línea Celular Tumoral , Humanos , Inhibidores de la Lipooxigenasa/farmacología , Linfoma Anaplásico de Células Grandes/enzimología , Masoprocol/análisis
8.
Biochem Biophys Res Commun ; 372(2): 351-5, 2008 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-18501703

RESUMEN

Phosphatidylinositol 5-monophosphate (PtdIns5P), one of the latest phosphoinositides discovered, has been suggested to play important cellular functions. Here, we report the presence of higher levels of this lipid in cells expressing the oncogenic tyrosine kinase nucleophosmin anaplastic lymphoma kinase (NPM-ALK), a chimeric protein found in the large majority of anaplastic large cell lymphomas (ALCLs). In addition, we describe that a pool of PtdIns5P is located in the membrane extensions characteristic of NPM-ALK-transformed cells. Finally, we show that the increase of PtdIns5P is controlled by the kinase PIKfyve, which is known for its role in vesicular trafficking. These data suggest for the first time a role of PtdIns5P and PIKfyve in oncogenesis, potentially linking intracellular trafficking to cancer.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Animales , Transformación Celular Neoplásica/genética , Humanos , Ratones , Células 3T3 NIH , Fosfatos de Fosfatidilinositol/análisis , Proteínas Tirosina Quinasas/genética
9.
Oncogene ; 27(19): 2728-36, 2008 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-17998938

RESUMEN

The majority of anaplastic large cell lymphomas (ALCLs) express the nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) fusion protein, which is oncogenic due to its constitutive tyrosine kinase activity. Transformation by NPM-ALK not only increases proliferation, but also modifies cell shape and motility in both lymphoid and fibroblastic cells. We report that the Rac1 GTPase, a known cytoskeletal regulator, is activated by NPM-ALK in ALCL cell lines (Karpas 299 and Cost) and transfected cells (lymphoid Ba/F3 cells, NIH-3T3 fibroblasts). We have identified Vav3 as one of the exchange factors involved in Rac1 activation. Stimulation of Vav3 and Rac1 by NPM-ALK is under the control of Src kinases. It involves formation of a signaling complex between NPM-ALK, pp60(c-src), Lyn and Vav3, in which Vav3 associates with tyrosine 343 of NPM-ALK via its SH2 domain. Moreover, Vav3 is phosphorylated in NPM-ALK positive biopsies from patients suffering from ALCL, demonstrating the pathological relevance of this observation. The use of Vav3-specific shRNA and a dominant negative Rac1 mutant demonstrates the central role of GTPases in NPM-ALK elicited motility and invasion.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/metabolismo , Linfoma Anaplásico de Células Grandes/enzimología , Proteínas Tirosina Quinasas/metabolismo , Proteínas Tirosina Quinasas/fisiología , Proteínas Proto-Oncogénicas c-vav/metabolismo , Transducción de Señal/fisiología , Proteína de Unión al GTP rac1/metabolismo , Quinasa de Linfoma Anaplásico , Animales , Proteína Tirosina Quinasa CSK , Línea Celular Tumoral , Factores de Intercambio de Guanina Nucleótido/fisiología , Humanos , Ratones , Células 3T3 NIH , Proteínas Nucleares/fisiología , Nucleofosmina , Fosfatidilinositol 3-Quinasas/fisiología , Proteínas Proto-Oncogénicas c-vav/fisiología , Proteínas Tirosina Quinasas Receptoras , Familia-src Quinasas/fisiología
10.
Leukemia ; 21(2): 215-21, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17170730

RESUMEN

Polymerase chain reaction (PCR) assessment of clonal T-cell receptor (TCR) and immunoglobulin (Ig) gene rearrangements is an important diagnostic tool in mature T-cell neoplasms. However, lack of standardized primers and PCR protocols has hampered comparability of data in previous clonality studies. To obtain reference values for Ig/TCR rearrangement patterns, 19 European laboratories investigated 188 T-cell malignancies belonging to five World Health Organization-defined entities. The TCR/Ig spectrum of each sample was analyzed in duplicate in two different laboratories using the standardized BIOMED-2 PCR multiplex tubes accompanied by international pathology panel review. TCR clonality was detected in 99% (143/145) of all definite cases of T-cell prolymphocytic leukemia, T-cell large granular lymphocytic leukemia, peripheral T-cell lymphoma (unspecified) and angioimmunoblastic T-cell lymphoma (AILT), whereas nine of 43 anaplastic large cell lymphomas did not show clonal TCR rearrangements. Combined use of TCRB and TCRG genes revealed two or more clonal signals in 95% of all TCR clonal cases. Ig clonality was mostly restricted to AILT. Our study indicates that the BIOMED-2 multiplex PCR tubes provide a powerful strategy for clonality assessment in T-cell malignancies assisting the firm diagnosis of T-cell neoplasms. The detected TCR gene rearrangements can also be used as PCR targets for monitoring of minimal residual disease.


Asunto(s)
Genes de Inmunoglobulinas , Leucemia de Células T/genética , Linfoma de Células T/genética , Reacción en Cadena de la Polimerasa/métodos , Receptores de Antígenos de Linfocitos T/genética , Amplificación de Genes , Reordenamiento Génico , Genotipo , Humanos , Inmunohistoquímica , Leucemia Prolinfocítica/genética , Leucemia Prolinfocítica/inmunología , Leucemia Prolinfocítica/patología , Leucemia de Células T/inmunología , Leucemia de Células T/patología , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células T/inmunología , Linfoma de Células T/patología , Linfocitos T/inmunología
11.
Leukemia ; 20(10): 1848-54, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16900211

RESUMEN

Anaplastic large cell lymphoma (ALCL) is a distinct subtype of non-Hodgkin's lymphoma. Most of ALCLs (85%) carry a chromosomal translocation involving different partners in the 5' portion, and the anaplastic lymphoma kinase (ALK) receptor kinase domain in the 3' portion. These translocations induce the ectopic expression of X-ALK proteins, thought to be involved in lymphomagenesis, through the dysregulation of cell proliferation and apoptotic pathways. In the present study, based on several ALK+ and ALK- ALCL cell lines and biopsy specimens, we showed that serpin A1, a secretory glycoprotein, was overexpressed in ALK+ ALCL cell lines and ALK+ tumors at both the transcriptional and translational levels. The crucial role of NPM-ALK in the regulation of serpin A1 expression was further demonstrated by using both ectopic expression and downregulation, by RNA interference, of the NPM-ALK oncogene. In addition, in ALK+ tumors, serpin A1 expression appeared to be correlated with the clinical status of the patients as the serpin A1 mRNA level was higher in patients presenting with extranodal dissemination. These data, together with the pattern of expression of serpin A1 we observed in ALK+ tumors, suggest that serpin A1 has an invasion-promoting effect in ALK+ ALCL.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/patología , alfa 1-Antitripsina/genética , Adulto , Quinasa de Linfoma Anaplásico , Biopsia , Línea Celular Tumoral , Niño , Humanos , Ganglios Linfáticos/patología , Linfoma de Células B Grandes Difuso/fisiopatología , Invasividad Neoplásica , Biosíntesis de Proteínas , Proteínas Tirosina Quinasas/genética , ARN Mensajero/análisis , Proteínas Tirosina Quinasas Receptoras , Transcripción Genética , Translocación Genética , alfa 1-Antitripsina/metabolismo
12.
J Clin Pathol ; 59(9): 995-6, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16935977

RESUMEN

Mantle cell lymphoma (MCL) is a B cell neoplasm that most often shows a diffuse growth pattern. Two cases of MCL are reported here, both with a previous diagnosis of lymphoid hyperplasia. Morphologically, germinal centres are hyperplasic with a normal or discretely enlarged mantle zone, where foci of irregularly shaped small lymphocytes are seen. These are positive for CD20, CD5 and cyclin D1, confirming a diagnosis of in situ-like MCL. This type differs from the mantle zone pattern in that the neoplastic mantle zone is very thin and there is very little or no spread of tumour cells into interfollicular areas. To the best of our knowledge, this is the first report on such a pattern of MCL, which is important to recognise, as it can be confused with lymphoid hyperplasia.


Asunto(s)
Linfoma de Células del Manto/patología , Anciano , Biomarcadores de Tumor/metabolismo , Ciclina D , Ciclinas/metabolismo , Diagnóstico Diferencial , Femenino , Humanos , Linfoma de Células del Manto/metabolismo , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Seudolinfoma/patología , Neoplasias Tonsilares/patología
13.
Neurosci Lett ; 401(3): 225-30, 2006 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-16621281

RESUMEN

Kisspeptins are peptide ligands of the G protein-coupled receptor GPR54, recently shown to be essential to reproductive function. We have raised specific rabbit antisera against a highly conserved 10 amino acid-amidated peptide (kp10) common to all kisspeptin isoforms isolated so far and mapped the distribution of kp10-immunoreactive (ir) cells in the ovine hypothalamus. Kp10-ir cells were predominant in the caudal arcuate nucleus, the dorsomedial nucleus and the medial preoptic area. Numerous varicose kp10-ir fibers were found in the preoptic area where GnRH neurons reside and in the median eminence, seemingly projecting around small capillaries in its external zone. Within the caudal arcuate nucleus, nearly all kp10-ir cells showed an intense estradiol receptor alpha immunofluorescent signal compared with approximately half of kp10-ir cells in the preoptic area. The pattern of distribution of kp10 immunoreactivity in the hypothalamus suggests a role for kisspeptin in the estrogen-dependent regulation of GnRH and LH secretion in the ewe.


Asunto(s)
Núcleo Arqueado del Hipotálamo/citología , Receptor alfa de Estrógeno/metabolismo , Neuronas/metabolismo , Área Preóptica/citología , Proteínas Supresoras de Tumor/metabolismo , Animales , Femenino , Humanos , Inmunohistoquímica/métodos , Kisspeptinas , Ratones , Radioinmunoensayo/métodos , Ovinos
14.
Horm Behav ; 48(1): 34-43, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15919383

RESUMEN

The influence of estrus, pregnancy, parturition, and maternal experience on the expression of estrogen receptor-alpha (ERalpha) was investigated in hypothalamic and limbic regions of the sheep brain, using immunocytochemistry. Four days before parturition, previous maternal experience was associated with a higher density of ERalpha-labeled neurons in the paraventricular and supraoptic nuclei, the medial preoptic area, and the medial amygdala, but not in the mediobasal hypothalamus. Furthermore, an interaction was found between physiological state and experience in the peripartum period as the effect of experience existing 4 days prepartum was not found at parturition, when densities were lowest both in primiparous and in multiparous ewes. An additional effect of physiological state was also observed between parturition and estrus, densities being significantly lower at parturition than at estrus in the SON, PVN, and MPOA, but not in the medial amygdala. These results indicate that in sheep ERalpha expression is influenced by previous physiological and/or maternal experience at specific times of the reproductive cycle. They are also congruent with the higher ability of multiparous than nulliparous ewes to show maternal behavior several days prepartum.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Sistema Límbico/metabolismo , Conducta Materna/fisiología , Parto/fisiología , Preñez/fisiología , Amígdala del Cerebelo/metabolismo , Animales , Estradiol/metabolismo , Femenino , Hipotálamo Anterior/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Paridad/fisiología , Embarazo , Área Preóptica/metabolismo , Progesterona/metabolismo , Ovinos , Coloración y Etiquetado
15.
J Neuroendocrinol ; 17(3): 145-51, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15796766

RESUMEN

Galanin is a neuropeptide involved in the regulation of numerous functions such as reproduction. In female rats, this peptide stimulates gonadotropin-releasing hormone (GnRH)/luteinizing hormone release and its synthesis is stimulated by oestradiol. It could therefore be an intermediary between the oestrogenic signal from the ovaries and the GnRH neurones (e.g. during the time course leading to the preovulatory GnRH surge). However, although the involvement of galanin is well-known in rodents, it is poorly understood in ewes. Using immunohistochemistry with a specific antigalanin antiserum, we detected the peptide in neurones of two groups of ovariectomized ewes treated for 6 h with subcutaneous implants, either with oestradiol (experimental group) or empty (control group). The galanin-immunoreactive neurones were counted in three areas, the preoptic area, the bed nucleus of the stria terminalis and the infundibular nucleus, using a computerized image analysis system. There was no change in the mean number of galanin-immunoreactive (GAL-ir) neurones in the infundibular nucleus (37 +/- 12 neurones/section in treated animals and 31 +/- 11 in controls) or in the bed nucleus of the stria terminalis (22 +/- 5 neurones/section in treated animals and 16 +/- 4 in controls), but the number of GAL-ir neurones was higher in the preoptic area in treated than in control ewes (35 +/- 4 versus 14 +/- 10, P < 0.001). To determine whether the neurones of the preoptic area were directly sensitive to oestradiol, we performed double immunohistochemical labelling for oestradiol receptor alpha and galanin. More than 50% of the GAL-ir neurones contained the oestradiol receptor alpha and therefore could be directly regulated by oestradiol. These results indicate that oestradiol might act directly on a GAL-ir neuronal population situated in the preoptic area, without any effect on the GAL-ir neurones of the infundibular nucleus or the bed nucleus of the stria terminalis. Because a 6-h oestradiol treatment can induce a preovulatory GnRH surge in ewes, the GAL-ir neuronal population of the preoptic area might be one of the neuronal systems by which oestradiol activates the GnRH neurones. However, although the morphological relationships between galanin and GnRH neurones have been described in rodents, they remain to be demonstrated in the ewe.


Asunto(s)
Estradiol/fisiología , Receptor alfa de Estrógeno/metabolismo , Galanina/metabolismo , Neuronas/metabolismo , Área Preóptica/metabolismo , Ovinos/fisiología , Animales , Núcleo Arqueado del Hipotálamo/metabolismo , Diencéfalo/citología , Diencéfalo/metabolismo , Ciclo Estral/metabolismo , Femenino , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Núcleos Septales/metabolismo
16.
Histopathology ; 46(3): 241-55, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15720410

RESUMEN

The generic term aggressive B-cell lymphoma includes a variety of entities, each with particular diagnostic and therapeutic issues. To define these entities better and to help confront such issues, a workshop was organized by the European Association of Haematopathology (EAHP) and the Society of Haematology during the XI Meeting of the EAHP, held in Italy in May 2002. Participants were asked to submit cases under various categories and all cases submitted were examined and reviewed by the panel members. The panel's diagnoses formed the basis for discussion at the workshop and a limited number of cases were selected to be presented in more detail and discussed during the workshop. After the workshop the panel met again to discuss the outcome, summarized in this report, which describes the panel's proposals regarding diagnostic criteria, terminology, the definition of new entities and evaluation of biological differential and new prognostic parameters.


Asunto(s)
Linfoma de Células B/clasificación , Linfoma de Células B/patología , Biomarcadores de Tumor/análisis , Congresos como Asunto , Humanos , Inmunohistoquímica , Linfoma de Células B/metabolismo
17.
Cell Mol Life Sci ; 61(23): 2939-53, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15583856

RESUMEN

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase, the normal role of which remains to be completely elucidated. Although work carried out in mammals suggests a function in neural development, results from studies in Drosophila indicate an additional role in visceral muscle differentiation. The aberrant expression of full-length ALK receptor proteins has been reported in neuroblastomas and glioblastomas, while the occurrence of ALK fusion proteins in anaplastic large cell lymphoma (ALCL) has resulted in the identification of the new tumor entity, ALK-positive ALCL. ALK represents one of few examples of a receptor tyrosine kinase implicated in oncogenesis in both haematopoietic and non-haematopoietic tumors, given that ALK fusions also occur in the mesenchymal tumor known as inflammatory myofibroblastic tumor (IMT). The study of ALK fusion proteins, besides demonstrating their importance in tumor development, has also raised the possibility of new therapeutic treatments for patients with ALK-positive malignancies.


Asunto(s)
Proteínas Tirosina Quinasas/fisiología , Adenoviridae/genética , Quinasa de Linfoma Anaplásico , Animales , Drosophila , Terapia Genética/métodos , Glioblastoma/metabolismo , Neoplasias Hematológicas/metabolismo , Humanos , Inmunoterapia , Linfoma/metabolismo , Modelos Biológicos , Modelos Genéticos , Neuroblastoma/metabolismo , Conformación Proteica , Estructura Terciaria de Proteína , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , ARN Catalítico/metabolismo , ARN Mensajero/metabolismo , Proteínas Tirosina Quinasas Receptoras , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Translocación Genética
18.
Leukemia ; 18(10): 1693-8, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15356659

RESUMEN

Anaplastic large-cell lymphoma (ALCL) is a distinct biological and cytogenetic entity with a broad spectrum of morphological features (common type, small-cell variant and lymphohistiocytic variant). Few cell lines of ALCL are available and they all originate from primary tumors demonstrating the common type morphology (ie large-sized lymphoma cells). We established a new ALCL cell line (COST) from the peripheral blood of a patient with a small-cell variant of ALCL, at diagnosis. Cells growing in vitro and in SCID mice consisted of two populations, that is, small- and large-sized cells as seen in the patient's tumor. Both large and small malignant cells were positive for CD43/MT1 T-cell associated antigen, perforin, granzyme B and TIA-1, but negative for CD2, CD3, CD5, CD7, CD4 and CD8 antigens. Standard cytogenetic studies as well as multiplex FISH confirmed the presence of the canonical t(2;5)(p23;q35) translocation, but also revealed additional numerical and structural abnormalities. The COST cell line is the first ALCL small-cell variant cell line, and thus provides a potentially useful tool for further functional and molecular studies that should improve our understanding of the small-cell variant of ALCL, which is more frequently complicated by a leukemic phase.


Asunto(s)
Linfoma Anaplásico de Células Grandes/patología , Células Tumorales Cultivadas , Animales , Antígenos CD/metabolismo , Preescolar , Aberraciones Cromosómicas , Cromosomas Humanos Par 2/genética , Cromosomas Humanos Par 5/genética , Análisis Citogenético , Femenino , Reordenamiento Génico de Linfocito T , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Técnicas In Vitro , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/inmunología , Masculino , Ratones , Ratones SCID , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Translocación Genética
20.
J Clin Oncol ; 21(15): 2948-52, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12885814

RESUMEN

PURPOSE: To clarify treatment strategy for lymphocyte-predominant Hodgkin's lymphoma (LPHL), the French Society of Pediatric Oncology initiated a prospective, nonrandomized study in 1988. Patients received either standard treatment for Hodgkin's lymphoma or were not treated beyond initial adenectomy. PATIENTS AND METHODS: From 1988 to 1998, 27 patients were available for study. Twenty-four patients were male, and median age was 10 years (range, 4 to 16 years). Twenty-two, two, and three patients had stage I, II, and III disease, respectively. Thirteen patients (stage I, n = 11; stage III, n = 2) received no further treatment after initial surgical adenectomy (SA). Fourteen patients received combined treatment (CT; n = 10), involved-field radiotherapy alone (n = 1), or chemotherapy alone (n = 3). The two groups were comparable for clinical status, treatment, and follow-up. RESULTS: Twenty-three of 27 patients achieved complete remission (CR). With a median follow-up time of 70 months (range, 32 to 214 months), overall survival to date is 100%, and overall event-free survival (EFS) is 69% +/- 10% (SA, 42% +/- 16%; CT, 90% +/- 8.6%; P <.04). If we considered only the patients in CR after initial surgery (n = 12), EFS was no longer significantly different between the two groups. Patients with residual mass after initial surgery (n = 15) had worse EFS if they did not receive complementary treatment (P <.05). CONCLUSION: Although based on a small number of patients, our study showed that (1). no further therapy is a valid therapeutic approach in LPHL patient in CR after initial lymph node resection, and (2). complementary treatment diminishes relapse frequency but has no impact on survival.


Asunto(s)
Enfermedad de Hodgkin/terapia , Escisión del Ganglio Linfático , Adolescente , Niño , Preescolar , Terapia Combinada , Femenino , Enfermedad de Hodgkin/patología , Humanos , Masculino , Recurrencia Local de Neoplasia , Estudios Prospectivos , Inducción de Remisión , Análisis de Supervivencia , Resultado del Tratamiento
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