RESUMO
BACKGROUND: The rare cutaneous solitary fibrous tumor was initially described in the thoracic cavity in relation to the pleura and subsequently been associated with other serous membranes. It has been described in other extraserosal locations including the skin. Knowledge of its existence along with fairly typical histological features and the immunohistochemical expression pattern with intense positivity for CD34 allow the increasing diagnosis of this condition, which suggests that these cases were not previously diagnosed as such. CLINICAL CASE: We report the case of a 43 year-old male with a painless nodule in the first left finger pad clinically suggestive of pyogenic granuloma or nodular melanoma, which was diagnosed by excisional biopsy and immunohistochemical study as a solitary fibrous tumor. DISCUSSION: Only 11 cases of cutaneous solitary fibrous tumor have been published in the following locations: head, cheek, thigh, chest, back and nose. Our work describes the first case of cutaneous solitary fibrous tumor in the hand. The solitary fibrous tumor derived from mesenchymal cells expresses CD34 and hence its presentation in any location. In our case it was in the hand. It explains the problems encountered in the clinical differential diagnosis with other tumors as nodular melanoma, pyogenic granuloma, giant cell tumor of tendon sheath, fibroma, benign peripheral nerve sheath tumors, etc. As we consider the histology, differential diagnosis should be made with other tumors that also express CD34. CONCLUSIONS: Solitary fibrous tumors derived from mesenchymal cells express CD34 and hence its presentation in any location. In our case it was in the finger pad.
Antecedentes: el tumor fibroso solitario es un tumor poco común. Anteriormente se suponía que afectaba sólo la cavidad torácica, en especial la pleura; posteriormente, se relacionó con otras membranas serosas y se observó en diversas localizaciones extraserosas, entre ellas la piel. El conocimiento de este tumor, junto con el aspecto histológico característico y el patrón de expresión inmunohistoquímica con intensa positividad para CD34 permiten que cada vez se diagnostique con mayor frecuencia. Caso clínico: se comunica el caso de un varón de 43 años de edad con un nódulo indoloro en el pulpejo del primer dedo izquierdo, que sugería clínicamente un melanoma nodular o granuloma piógeno. Mediante biopsia excisional y estudio inmunohistoquímico se diagnosticó como tumor fibroso solitario. Discusión: hasta la fecha se han publicado 11 casos de tumores fibrosos solitarios cutáneos, localizados en cabeza, mejilla, muslo, pecho, espalda y vestíbulo nasal. El caso que se comunica constituye la primera lesión de estas características que afecta la mano. El diagnóstico clínico diferencial del tumor fibroso solitario incluye otros tumores como: melanoma nodular, granuloma piógeno, tumor de células gigantes tenosinovial, fibroma y tumor de vaina de nervio periférico benigno. En cuanto a la histología, se planteó el diagnóstico diferencial con otras neoplasias que también expresan CD34. Conclusiones: el tumor fibroso solitario deriva de células mesenquimatosas y expresa CD34, lo que explica su aparición en cualquier localización, como en este caso, que fue en el pulpejo del quinto dedo.
Assuntos
Antígenos CD34/análise , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Hemangiopericitoma/patologia , Tumores Fibrosos Solitários/patologia , Polegar/patologia , Adulto , Apigenina/análise , Biópsia , Proteínas de Ligação a Calmodulina/análise , Diagnóstico Diferencial , Glucosídeos/análise , Granuloma Piogênico/diagnóstico , Hemangiopericitoma/química , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/cirurgia , Humanos , Masculino , Melanoma/diagnóstico , Mesoderma/química , Proteínas Proto-Oncogênicas c-bcl-2/análise , Tumores Fibrosos Solitários/química , Tumores Fibrosos Solitários/diagnóstico , Tumores Fibrosos Solitários/cirurgia , Polegar/cirurgiaRESUMO
OBJECTIVE: Follicular dendritic cells (FDCs) and interdigitating dendritic cells (IDCs) are dendritic cells found in lymphoid follicles, reactive follicles and in lymphomas. The goal of this study was to evaluate the presence and distribution of FDCs and IDCs in oral lymphomas. MATERIAL AND METHODS: Immunohistochemistry reactions were applied to 50 oral lymphomas using the antibodies anti-CD21, anti-CD35 and anti-caldesmon to FDCs, and anti-S100 protein to IDCs. Caldesmon+/FDCs and S100+/IDCs were quantified in Imagelab® software. RESULTS: FDCs revealed by CD21 and CD35 were positively stained in two cases of diffuse large B-cell lymphoma, one MALT lymphoma, and in one case of mantle cell lymphoma. FDCs were immunopositive to caldesmon in all cases, as well as IDCs to S100 protein. Burkitt lymphoma presented a lower amount of caldesmon+/FDCs and S100+/IDCs than diffuse large B-cell lymphoma and plasmablastic lymphoma of the oral mucosa type. CONCLUSIONS: The microenvironment determined by neoplastic lymphoid cells in oral lymphomas is responsible by the development and expression of dendritic cells types.
Assuntos
Humanos , Células Dendríticas Foliculares/química , Células Dendríticas/química , Linfoma não Hodgkin/química , Neoplasias Bucais/química , Proteínas de Ligação a Calmodulina/análise , Imuno-Histoquímica , Linfoma de Zona Marginal Tipo Células B/química , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Difuso de Grandes Células B/química , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Célula do Manto/química , Linfoma de Célula do Manto/patologia , Linfoma não Hodgkin/patologia , Neoplasias Bucais/patologia , /análise , /análise , /análiseRESUMO
OBJECTIVE: Follicular dendritic cells (FDCs) and interdigitating dendritic cells (IDCs) are dendritic cells found in lymphoid follicles, reactive follicles and in lymphomas. The goal of this study was to evaluate the presence and distribution of FDCs and IDCs in oral lymphomas. MATERIAL AND METHODS: Immunohistochemistry reactions were applied to 50 oral lymphomas using the antibodies anti-CD21, anti-CD35 and anti-caldesmon to FDCs, and anti-S100 protein to IDCs. Caldesmon+/FDCs and S100+/IDCs were quantified in Imagelab software. RESULTS: FDCs revealed by CD21 and CD35 were positively stained in two cases of diffuse large B-cell lymphoma, one MALT lymphoma, and in one case of mantle cell lymphoma. FDCs were immunopositive to caldesmon in all cases, as well as IDCs to S100 protein. Burkitt lymphoma presented a lower amount of caldesmon+/FDCs and S100+/IDCs than diffuse large B-cell lymphoma and plasmablastic lymphoma of the oral mucosa type. CONCLUSIONS: The microenvironment determined by neoplastic lymphoid cells in oral lymphomas is responsible by the development and expression of dendritic cells types.
Assuntos
Células Dendríticas Foliculares/química , Células Dendríticas/química , Linfoma não Hodgkin/química , Neoplasias Bucais/química , Proteínas de Ligação a Calmodulina/análise , Humanos , Imuno-Histoquímica , Linfoma de Zona Marginal Tipo Células B/química , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Difuso de Grandes Células B/química , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Célula do Manto/química , Linfoma de Célula do Manto/patologia , Linfoma não Hodgkin/patologia , Neoplasias Bucais/patologia , Receptores de Complemento 3b/análise , Receptores de Complemento 3d/análise , Proteínas S100/análiseRESUMO
BACKGROUND: Pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) are neoplasms of distinct behaviour, showing similar origin, cell components and marked presence of extracellular matrix (ECM). Interactions between cells and ECM are important in the biology of tumours, being partially mediated by integrins. This study investigated these interactions on PA and ACC using paraffin-embedded tissue and an in vitro model of these conditions. METHODS: Expression of integrins in paraffin-embedded samples was assessed by immunohistochemistry. Cells from PA and ACC were characterized using immunofluorescence, and integrin patterns of expression were investigated on cells cultivated on different ECM proteins. RESULTS: Luminal cells of both PA and ACC were more intensely positive for integrins than myoepithelial cells. In vitro studies revealed that PA cells expressed more integrins than ACC cells regardless the ECM protein present. CONCLUSIONS: This study revealed particular patterns of integrin expression in both specimens and in vitro models of PA and ACC. This might prove useful for a better understanding of the biology of these lesions.
Assuntos
Adenoma Pleomorfo/patologia , Carcinoma Adenoide Cístico/patologia , Matriz Extracelular/patologia , Integrinas/análise , Actinas/análise , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação a Calmodulina/análise , Colágeno Tipo I/análise , Colágeno Tipo IV/análise , Fibroblastos/patologia , Fibronectinas/análise , Humanos , Integrina alfa2/análise , Integrina alfa3/análise , Integrina alfa5/análise , Integrina beta1/análise , Laminina/análise , Proteínas dos Microfilamentos , Células Estromais/patologia , Vimentina/análise , CalponinasRESUMO
The subcellular localization in brain of an unconventional, calmodulin-binding myosin (myosin-V) found in neurons, astrocytes and other secretory cells of vertebrates has been investigated by probing Western blots of synaptic fractions from rat cerebral cortex with affinity-purified polyclonal antibodies against myosin-V. Myosin-V was detected in intact synaptosomes and in lysed synaptosomes associated with a particulate fraction. Our data suggest a role for brain myosin-V in membrane-cytoskeleton function in the synaptic region.
Assuntos
Proteínas de Ligação a Calmodulina/análise , Córtex Cerebral/química , Miosina Tipo V , Proteínas do Tecido Nervoso/análise , Sinaptossomos/química , Animais , RatosRESUMO
We have recently identified a novel 190-kD calmodulin-binding protein (p190) associated with the actin-based cytoskeleton from mammalian brain (Larson, R. E., D. E. Pitta, and J. A. Ferro. 1988. Braz. J. Med. Biol. Res. 21:213-217; Larson, R. E., F. S. Espindola, and E. M. Espreafico. 1990. J. Neurochem. 54:1288-1294). These studies indicated that p190 is a phosphoprotein substrate for calmodulin-dependent kinase II and has calcium- and calmodulin-stimulated MgATPase activity. We now have biochemical and immunological evidence that this protein is a novel calmodulin-binding myosin whose properties include (a) Ca2+ dependent action activation of its Mg-ATPase activity, which seems to be mediated by Ca2+ binding directly to calmodulin(s) associated with p190 (maximal activation by actin requires the presence of Ca2+ and is further augmented by addition of exogenous calmodulin); (b) ATP-sensitive cross-linking of skeletal muscle F-actin, as demonstrated by the low-speed actin sedimentation assay; and (c) cross-reactivity with mAbs specific for epitopes in the head of brush border myosin I. We also show that p190 has properties distinct from conventional brain myosin II and brush border myosin I, including (a) separation of p190 from brain myosin II by gel filtration on a Sephacryl S-500 column; (b) lack by p190 of K(+)-stimulated EDTA ATPase activity characteristic of most myosins; (c) lack of immunological cross-reactivity of polyclonal antibodies which recognize p190 and brain myosin II, respectively; (d) lack of immunological recognition of p190 by mAbs against an epitope in the tail region of brush border myosin I; and (e) distinctive proteolytic susceptibility to calpain. A survey of rat tissues by immunoblotting indicated that p190 is expressed predominantly in the adult forebrain and cerebellum, and could be detected in embryos 11 d post coitus. Immunocytochemical studies showed p190 to be present in the perikarya and dendritic extensions of Purkinje cells of the cerebellum.
Assuntos
Adenosina Trifosfatases/metabolismo , Encéfalo/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Calmodulina/metabolismo , Proteínas do Citoesqueleto/isolamento & purificação , Miosinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Adenosina Trifosfatases/análise , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Encéfalo/embriologia , Proteínas de Ligação a Calmodulina/análise , Proteínas de Ligação a Calmodulina/isolamento & purificação , Galinhas , Eletroforese em Gel de Poliacrilamida , Desenvolvimento Embrionário e Fetal , Epitopos/análise , Feminino , Imuno-Histoquímica , Masculino , Peso Molecular , Miosinas/análise , Miosinas/isolamento & purificação , Proteínas do Tecido Nervoso/análise , Especificidade de Órgãos , Células de Purkinje/citologia , Células de Purkinje/metabolismo , Coelhos , Ratos , Especificidade da EspécieRESUMO
The aim of this work was the identification of the calmodulin-stimulated protein phosphatase, calcineurin, in rat pancreatic islets. For this purpose, a high-affinity calcineurin antibody and the Western blotting technique were used to detect the presence of calcineurin in freshly collagenase-isolated islets. The calcineurin content detected by this method was about 0.30 ng islet (approx. 0.07% of the total islet protein). The subunit composition and Mr of islet calcineurin were similar to those of bovine brain calcineurin. Incubation of nitrocellulose membranes of the Western blotting, containing the islet protein fractions, with 125I-labeled calmodulin and 45Ca2+ demonstrated that the A subunit bound calmodulin, while the B subunit bound Ca2+. The presence of calcineurin in the islets of Langerhans would suggest its possible participation, as a counterpart of the kinases effect, in the regulatory mechanism of insulin secretion.
Assuntos
Proteínas de Ligação a Calmodulina/análise , Ilhotas Pancreáticas/enzimologia , Fosfoproteínas Fosfatases/análise , Animais , Western Blotting , Calcineurina , Cálcio/metabolismo , Calmodulina/metabolismo , Proteínas de Ligação a Calmodulina/isolamento & purificação , Proteínas de Ligação a Calmodulina/metabolismo , Substâncias Macromoleculares , Masculino , Peso Molecular , Fosfoproteínas Fosfatases/isolamento & purificação , Fosfoproteínas Fosfatases/metabolismo , Ligação Proteica , Ratos , Ratos EndogâmicosRESUMO
We present evidence for a novel calmodulin-binding protein associated with Ca2+-sensitive, non-muscle actomyosin from rabbit brain. Gel filtration chromatography of brain actomyosin and SDS-PAGE analysis of resulting fractions revealed the presence of a stable complex of a 190 kDa polypeptide and calmodulin. Furthermore, brain actomyosin was retained on a column of conjugated calmodulin-Sepharose 4B and eluted by 6 M urea in the presence of Ca2+. Further elution with 6M urea plus EGTA released the 190 kDa polypeptide from the column. These results show that the 190 kDa polypeptide forms a tight complex with calmodulin and that this complex associates with brain actomyosin in a Ca2+-independent manner.