932 resultados para P19 embryonal carcinoma cells


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Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, and most people have serological evidence of previous viral infection at adult age. EBV is associated with infectious mononucleosis and human cancers, including some lymphomas and gastric carcinomas. Although EBV was first reported in lymphoepithelioma-like gastric carcinoma, the virus was also found in conventional adenocarcinomas. In the present study, 53 gastric carcinomas diagnosed in São Paulo State, Brazil, were evaluated for EBV infection by non-isotopic in situ hybridization with a biotinylated probe (Biotin-AGACACCGTCCTCACCACCC GGGACTTGTA) directed to the viral transcript EBER-I, which is actively expressed in EBV latently infected cells. EBV infection was found in 6 of 53 (11.32%) gastric carcinomas, mostly from male patients (66.7%), with a mean age of 59 years old. Most EBV-positive tumors were in gastric antrum. Two EBV-positive tumors (33.3%) were conventional adenocarcinomas, whereas four (66.7%) were classified as lymphoepithelioma-like carcinomas. EBV infection in gastric carcinomas was reported elsewhere in frequencies that range from 5.6% (Korea) up to 18% (Germany). In Brazil, a previous work found EBV infection in 4 of 80 (5%) gastric carcinomas, whereas another study found 4.7 and 11.2% of EBV-positive gastric carcinomas of Brazilians of Japanese origin or not, respectively. In the present study, the frequency of EBV-positive gastric carcinomas is similar to that reported in other series, and the clinicopathologic characteristics of these EBV-positive tumors are in agreement with the data in the literature.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Introdução: Recentemente o papilomavírus humano (HPV) tem sido associado à carcinogênese oral. A metodologia empregada na detecção do vírus é uma das maiores causas observadas da grande variabilidade nas taxas de detecção do HPV. Objetivo: Este estudo comparou a sensibilidade de detecção do DNA do HPV em casos de carcinoma epidermoide de lábio utilizando a amplificação do DNA viral por reação em cadeia da polimerase (PCR) ou nPCR. Material e método: Foram utilizadas 33 amostras provenientes de casos de carcinoma epidermoide de lábio. Para as extrações do DNA utilizou-se o sistema QIAamp DNA Mini Kit. Como controle interno utilizou-se o gene da b-globina. Das 33 amostras iniciais, 30 foram positivas para o gene b-globina, sendo utilizadas para detectar o DNA viral. Comparou-se a amplificação do DNA viral pelos métodos da PCR com os oligonucleotídeos MY09/MY11 e nPCR, empregando-se os pares de oligonucleotídeos iniciadores MY09/MY11 e, na segunda etapa, o par GP5+/GP6+. O controle positivo para a presença do DNA do HPV utilizado foi a linhagem de células HeLa e, como controle negativo, a mistura de amplificação sem DNA. A análise dos produtos de PCR e nPCR para HPV foi realizada por eletroforese em gel de poliacrilamida a 8%. Resultados: Utilizando-se o método da PCR, a amplificação do DNA do HPV foi constatada em dois casos. Com a nPCR foi verificada presença de DNA viral em 13 das 30 amostras. Conclusão: Com a utilização da nPCR, a detecção do HPV nos casos estudados aumentou mais de seis vezes.

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This study aims to present the clinical features and treatment of a case of maxillary ameloblastic carcinoma. A meloblastic carcinoma is a rare malignant odontogenic carcinoma that has metastatic potential. Due to its rare incidence, there are few studies focusing on its radiological characteristics. When ameloblastic carcinoma demonstrates an aggressive appearance, it may be diagnosed as a malignant tumor; however, in cases showing a non-aggressive appearance, it is difficult to distinguish ameloblastic carcinoma from ameloblastoma. We report a case of ameloblastic carcinoma of the maxilla in a 59-year-old male patient, including the clinical signs, radiological images and pathological features. A partial area was surgically excised under local anesthesia and the material was sent to the Laboratory of Oral Pathology. The histological sections revealed a fragmented odontogenic tumor of epithelial origin, consisting of solid parenchyma and also revealed basal cells resembling ameloblasts, occasionally arranged in palisades. Certain parts of the architecture resembled that of an ameloblastoma; however, the cytology of other areas confirmed the diagnosis of ameloblastic carcinoma of the maxilla. The patient was scheduled for definitive surgery, including a right maxillectomy and radiotherapy. The patient was followed up every 3 months. After 2 years follow-up, there were no clinical or radiological signs of recurrence.

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Aims: This multi-centre analysis assessed the DNA content of TSCC in 37 young patients (<40 years) and 28 old patients (>50 years) and determined the correlation of DNA ploidy findings with clinicopathological data.Methods and results: Image cytometry was carried out using an automated cellular imaging system on Feulgen-stained histological sections to obtain high-fidelity DNA histograms. Among young patients, 37.8% were females compared to 18.7% in the older group (P = 0.002). In total, 48.6% patients were non-smokers and 40.5% were non-drinkers compared to 10.7% non-smokers and non-drinkers in the older group (P < 0.0001). TNM, clinical stage of disease and histological grade of differentiation did not differ between groups. Tumour aneuploidy was detected in 86.5% and tetraploidy in 24.3% young patients; this was significantly greater than in the older group where 64.3% were aneuploid (P < 0.0001) and 7.2% tetraploid (P < 0.0001). The mean values of DNA index (DI) and DNA heterogeneity index as well as the percentage of cells with DI exceeding 5N were higher in young patients (P < 0.0001).Conclusions: Young patients with TSCC represent a distinct clinical entity. The high incidence of DNA ploidy abnormalities suggest that they may have increased genomic instability and indicates underlying genetic differences between TSCC in young and older patients.

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The 5-year survival rate for oral cavity cancer is poorer than for breast, colon or prostate cancer, and has improved only slightly in the last three decades. Hence, new therapeutic strategies are urgently needed. Here we demonstrate by tissue micro array analysis for the first time that RNA-binding protein La is significantly overexpressed in oral squamous cell carcinoma (SCC). Within this study we therefore addressed the question whether siRNA-mediated depletion of the La protein may interfere with known tumor-promoting characteristics of head and neck SCC cells. Our studies demonstrate that the La protein promotes cell proliferation, migration and invasion of lymph node-metastasized hypopharyngeal SCC cells. We also reveal that La is required for the expression of beta-catenin as well as matrix metalloproteinase type 2 (MMP-2) within these cells. Taken together these data suggest a so far unknown function of the RNA-binding protein La in promoting tumor progression of head and neck SCC.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Annexin 1 protein (ANXA1) expression was evaluated in tumor and mast cells in human larynx cancer and control epithelium. The effect of the exogenous ANXA1 (peptide Ac 2-26) was also examined during the cellular growth of the Hep-2 human larynx epidermoid carcinoma cell line. This peptide inhibited the proliferation of the Hep-2 cells within 144 hr. In surgical tissue specimens from 20 patients with larynx cancer, ultrastructural immunocytochemistry analysis showed in vivo down-regulation of ANXA1 expression in the tumor and increased in mast cells and Hep-2 cells treated with peptide Ac2-26. Combined in vivo and in vitro analysis demonstrated that ANXA1 plays a regulatory role in laryngeal cancer cell growth. We believe that a better understanding of the regulatory mechanisms of ANXA1 in tumor and mast cells may lead to future biological targets for the therapeutic intervention of human larynx cancer. (c) 2007 Wiley-Liss, Inc.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Atualmente, muito se discute a respeito da natureza pré-maligna do líquen plano bucal. OBJETIVO: O presente trabalho tem como objetivo analisar as alterações das células epiteliais presentes no líquen plano bucal, comparando-as com aquelas observadas no carcinoma epidermóide. MATERIAL E MÉTODO: Cortes histológicos de líquen plano bucal e carcinoma epidermóide, corados com hematoxilina-eosina, foram analisados por meio da microscopia de luz. RESULTADO: As alterações mais frequentemente observadas no líquen plano bucal foram aumento da relação núcleo/citoplasma (93,33%), espessamento da membrana nuclear (86,67%) e bi-ou multinucleação (86,67%). O teste t de Student (alfa=5%) revelou haver diferença estatisticamente significante entre o número médio de alterações celulares no líquen plano bucal (5,87±1,57) e no carcinoma epidermóide (7,60±1,81). Quanto aos tipos de alterações, o teste de qui-quadrado também revelou haver diferença estatisticamente significante entre as lesões avaliadas em relação às seguintes alterações celulares: hipercromatismo nuclear, mitoses atípicas, pleomorfismo celular e diferenciação celular anormal (p<0,05). CONCLUSÃO: Apesar de que, em alguns casos, alguns patologistas possam fazer confusão no diagnóstico histopatológico do líquen plano bucal, os resultados obtidos neste estudo mostram que as alterações presentes no líquen plano bucal diferem consideravelmente daquelas observadas no carcinoma epidermóide, evidenciando o quão distintas são estas duas doenças.

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Epstein-Barr virus (EBV) has been associated with 10% of gastric carcinomas. The aim of this study was to determine the frequency of EBV in gastric carcinomas in Brazil assessed by in situ hybridization (ISH) and PCR, which would contribute to the characterization of the clinical and pathological aspects of EBV-associated gastric carcinomas. One hundred and ninety-two gastric carcinoma cases were collected at hospitals in two Brazilian states. Seventy-three out of 151 cases were PCR(+), while 11/160 cases were ISH(+). Nine out of eleven ISH(+) cases displayed a diffuse staining pattern and 2 out of 11 a focal pattern. Both techniques showed that the EBV(+) cases were characterized by their association with males, older patients, lower gastric region, intestinal type, advanced stage and poorly to moderately differentiated tumors. The concordance between the two techniques was 55.8% (Cohen's kappa index = 0.034). Four cases were ISH(+)/PCR(-), while 49 cases were PCR(+)/ISH(-). Only two cases showed stained lymphocytes by ISH and one of them was PCR(-). The observed discrepancy between the two techniques could not be explained just by the elevated accuracy of PCR. ISH(+)/PCR(-) carcinomas may be encountered if EBV is not present in the whole tumor tissue or if there are polymorphisms in the sequences of the viral genome amplified. on the other hand, the high frequency of PCR(+) results associated with the absence of ISH staining in lymphocytes and/or tumors cells suggests that the virus may be present in tumor cells or other cell types without expressing EBER1, the target of the ISH technique.

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RACIONAL: O carcinoma basalóide escamoso ocorre com maior freqüência no trato aerodigestivo superior e raramente acomete o esôfago. OBJETIVO: Apresentar os aspectos clínico-patológicos e os atributos imunoistoquímicos de um paciente com carcinoma basalóide escamoso do esôfago. RELATO do CASO: Dos 134 pacientes com câncer do esôfago atendidos no Hospital Universitário de Botucatu-Unesp, São Paulo, de 1990 a 1999, somente um paciente (0,74%) apresentou carcinoma basalóide escamoso do esôfago. Tratava-se de paciente masculino, 41 anos, branco, lavrador com disfagia, regurgitação e emagrecimento há três meses. Referia tabagismo e etilismo há muitos anos. O esofagograma e o exame endoscópico revelaram lesão vegetante no terço distal do esôfago. A biópsia demonstrou neoplasia intraepitelial de alto grau associada a blocos de células basalóides que infiltravam o cório da mucosa, caracterizando o carcinoma basalóide escamoso. Os marcadores imunoistoquímicos foram positivos para o antígeno carcinoembriônico e para citoceratinas de alto peso molecular. A tomografia computadorizada revelou múltiplas metástases nos pulmões, fígado, e nódulos linfáticos regionais, documentando a fase avançada de evolução da doença. O tratamento consistiu apenas na realização de gastrostomia. O paciente apresentou queda acentuada do estado geral e evoluiu para óbito com quadro de melena quatro meses após o diagnóstico. CONCLUSÃO: O carcinoma basalóide escamoso é uma forma rara e agressiva de câncer do esôfago e o prognóstico depende do estadiamento da lesão e das condições clínicas do paciente no momento do diagnóstico.

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Acinic cell carcinoma (ACC) is a rare salivary gland tumour, making up 4% of all minor salivary gland tumours. Typically, it is composed of acinic cells although transitional and duct-like cells are also identified. In the present study, a panel of antibodies was applied to eight minor salivary gland ACCs. Antibodies tested were: cytokeratins 7, 8, 13, 14, 18, 19, vimentin and actin (HHF35). Immunohistochemical staining revealed that cytokeratin 8, among the tested antibodies, was the more specific to neoplastic cells with a pattern of distribution quite variable and peculiar. This staining may be useful in the recognition of neoplastic acinic cells. (C) 1997 Elsevier B.V. Ltd.

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This study examined the expression of epidermal growth factor (EGF) cell-surface receptors, the response to exogenous ligand and the autocrine production of transforming growth factor a (TGF-a) in normal and carcinoma-derived human oral keratinocytes. One of eight malignant cell lines overexpressed EGF receptors, while the remainder expressed receptor numbers similar to normal cells. Exogenous EGF stimulated incorporation of tritiated thymidine in a dose-dependent manner. In keratinocytes expressing normal numbers of EGF receptors, the cellular response to exogenous EGF correlated positively with total EGF receptor number. SCC-derived keratinocytes produced more TGF-a than normal cells. There was no statistical correlation between the autocrine production of TGF-a, EGF cell-surface receptor expression and cellular response to exogenous EGF. While the growth-stimulatory effects of exogenous TGF-cl were inhibited by the addition of a neutralising antibody, the presence of this antibody in conditioned medium failed to produce a similar decrease in growth. The results indicate that overexpression of EGF receptors is not an invariable characteristic of human oral squamous carcinoma-derived cell lines. Further, the contribution of TGF-a to the growth of normal and carcinoma-derived human oral keratinocytes in vitro may be less significant than previously documented.