Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros










Intervalo de año de publicación
1.
Br J Dermatol ; 182(1): 147-155, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31049933

RESUMEN

BACKGROUND: The malignant mechanisms that control the development of cutaneous T-cell lymphoma (CTCL) are beginning to be identified. Recent evidence suggests that disturbances in specific intracellular signalling pathways, such as RAS-mitogen-activated protein kinase, T-cell receptor (TCR)-phospholipase C gamma 1 (PLCG1)-nuclear factor of activated T cells (NFAT) and Janus kinase (JAK)-signal transducer and activator of transcription (STAT), may play an essential role in the pathogenesis of CTCL. OBJECTIVES: To investigate the mechanisms controlling disease development and progression in mycosis fungoides (MF), the most common form of CTCL. METHODS: We collected 100 samples that were submitted for diagnosis of, or a second opinion regarding, MF between 2001 and 2018, 80% of which were in the early clinical stages of the disease. Formalin-fixed paraffin-embedded tissues were used for histological review and to measure the expression by immunohistochemistry of surrogate markers of activation of the TCR-PLCG1-NFAT, JAK-STAT and NF-κB pathways. Folliculotropism and large-cell transformation were also examined. RESULTS: NFAT and nuclear factor kappa B (NF-κB) markers showed a comparable activation status in early and advanced stages, while STAT3 activation was more frequent in advanced stages and was associated with large-cell transformation. Consistently with this observation, STAT3 activation occurred in parallel with MF progression in two initially MF-negative cases. A significant association of NFAT with NF-κB markers was also found, reflecting a common mechanism of activation in the two pathways. Genomic studies identified nine mutations in seven genes known to play a potential role in tumorigenesis in T-cell leukaemia/lymphoma, including PLCG1, JAK3 and STAT3, which underlies the activation of these key cell-survival pathways. A higher mutational allele frequency was detected in advanced stages. CONCLUSIONS: Our results show that STAT3 is activated in advanced cases and is associated with large-cell transformation, while the activation of NFAT and NF-κB is maintained throughout the disease. These findings could have important diagnostic and therapeutic implications. What's already known about this topic? Mycosis fungoides is characterized by a clonal expansion of T cells in the skin. The mechanisms controlling disease development and progression are not fully understood. What does this study add? An association of the nuclear factor of activated T cells and nuclear factor kappa B pathways was found, which could reflect a common mechanism of activation. These pathways were activated in early and advanced stages at the same level. Signal transducer and activator of transcription 3 activation was associated with large-cell transformation and was more frequent in advanced stages. A genomic analysis of cutaneous T-cell lymphoma-associated genes was performed. Nine mutations were detected. What is the translational message? These results could have important implications for the treatment of MF in the near future.


Asunto(s)
Linfoma Cutáneo de Células T , Micosis Fungoide , FN-kappa B , Factores de Transcripción NFATC , Factor de Transcripción STAT3 , Neoplasias Cutáneas , Humanos , Micosis Fungoide/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Neoplasias Cutáneas/genética , Linfocitos T/metabolismo
4.
Acta Cytol ; 41(3): 786-94, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9167703

RESUMEN

OBJECTIVE: To assess the value of fine needle aspiration cytology (FNAC) in the diagnosis of pleomorphic adenoma and to determine the cytologic variations responsible for diagnostic errors. STUDY DESIGN: We retrospectively studied 212 cases cytologically diagnosed as pleomorphic adenoma. In 184 a histologic diagnosis was available. Fourteen cases of histologically proven pleomorphic adenomas with a previously erroneous cytologic diagnosis were also reviewed. This study was based on those cases with a histologic diagnosis. RESULTS: The sensitivity and specificity of the cytologic diagnosis of pleomorphic adenoma in our series were 92.6% and 98.4%, respectively. In relation to malignancy, the series showed six false negative and three false positive diagnoses. In those cases correctly diagnosed on aspiration (175), a typical cytologic appearance, with no diagnostic difficulties, was observed in 118 cases (67.4%); the remainder showed cytologic variations. Cellular atypia (20.6%), cystic transformation (7%) and the presence of a cylindromatous pattern (5%) resembling adenoid cystic carcinoma were the most common cytologic variations observed and responsible for the majority of the errors. CONCLUSION: The cytologic variations in FNAC of pleomorphic adenoma must be considered in order to avoid important errors in the preoperative management of and surgical approach to salivary gland lesions.


Asunto(s)
Adenoma Pleomórfico/patología , Biopsia con Aguja , Neoplasias de las Glándulas Salivales/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Errores Diagnósticos , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
5.
Am J Gastroenterol ; 91(4): 810-1, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8677962

RESUMEN

We report a solitary fibrous tumor of the abdominal cavityt that presented as a encapsulated mass attached to the mesentery in a 33-yr-old man. Histologically, the lesion showed a disorganized arrangement of spindle cells in a collagenous background and prominent vascular channels of varying size. Tumor cells showed immunohistochemical reactivity for vimentin only. Cytokeratins and CD34 were negative. This report further extends the anatomic range of solitary fibrous tumor, a neoplasm that must be included in the differential diagnosis of well-defined abdominal masses. The behavior of this mesenteric solitary fibrous tumor has been benign.


Asunto(s)
Mesenterio/patología , Mesotelioma/patología , Neoplasias Peritoneales/patología , Adulto , Humanos , Masculino , Mesotelioma/metabolismo , Mesotelioma/cirugía , Neoplasias Peritoneales/metabolismo , Neoplasias Peritoneales/cirugía , Vimentina/análisis
6.
Virchows Arch ; 427(3): 259-63, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7496594

RESUMEN

A recent in vitro study has suggested that overexpression of ERBB2 may mediate breast tumour progression and metastasis by inhibiting the transcription of the E-cadherin (E-CD) gene. To test this hypothesis in human breast cancer in vivo, we studied the relationship between the expression of both molecules in 247 breast carcinomas immunohistochemically. Five ductal carcinomas in situ overexpressed ERBB2 and showed preserved E-CD expression. Forty-four of 226 infiltrating ductal carcinomas (19.47%) showed ERBB2 overexpression, and a statistically significant relationship was found between ERBB2 overexpression and high histological grade. E-CD expression was preserved in 111 cases (49.1%) and correlated with the histological grade. However, no significant relationship was found between ERBB2 and E-CD expression. None of the 16 infiltrating lobular carcinomas expressed ERBB2 or E-CD. These observations in different histological types of breast carcinoma strongly argue against a role for ERBB2 as a transcriptional regulator of E-CD expression in most human breast carcinomas in vivo.


Asunto(s)
Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Carcinoma in Situ/metabolismo , Carcinoma Ductal de Mama/metabolismo , Receptor ErbB-2/metabolismo , Femenino , Humanos , Inmunohistoquímica
7.
Mod Pathol ; 7(3): 392-5, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8058714

RESUMEN

This study analyzes the usefulness of the polymerase chain reaction technique in the detection of delta F508 mutation in 11- to 25-yr-old formalin-fixed paraffin-embedded tissues obtained from the autopsy of 38 cystic fibrosis patients (nine with meconium ileus). Two different pairs of oligonucleotide primers were used: C16 B/C16 D that amplify 98 and/or 95 bp and FQ1/FQ2 that amplify 50 and/or 47 bp. After two independent rounds of polymerase chain reactions with the two sets of primers, amplification products were obtained in 67.5% of the cases when using C16 B/C16 D primers and in all cases when using FQ1/FQ2 primers. Fifty percent of the chromosomes analyzed in the 29 patients without meconium ileus had the delta F508 mutation, which was present in 13 heterozygous and 8 homozygous patients. The remaining eight cystic fibrosis patients did not carry that mutation. These results are similar to those reported in cystic fibrosis patients from Spain. In the meconium ileus group, we found a higher than expected proportion of delta F508 mutation; all patients showed the delta F508 mutation in at least one chromosome, seven patients (77.8%) being homozygous and two (22.2%) heterozygous. Present results indicate that delta F508 mutation can be detected by polymerase chain reaction in old paraffin-embedded tissues when appropriate primers are used.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Fibrosis Quística/genética , Mutación , Secuencia de Bases , Fibrosis Quística/patología , Análisis Mutacional de ADN/métodos , Cartilla de ADN , Electroforesis en Gel de Agar , Formaldehído , Humanos , Recién Nacido , Meconio , Datos de Secuencia Molecular , Adhesión en Parafina , Reacción en Cadena de la Polimerasa/métodos , Estudios Retrospectivos , Fijación del Tejido
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...