The canonical wnt pathway in gastric carcinoma / Via canônica do wnt no carcinoma gástrico

ABSTRACT Background : It is believed that the Wnt pathway is one of the most important signaling involved in gastric carcinogenesis. Aim : To analyze the protein expression of canonical and non-canonical Wnt pathways in gastric carcinoma. Method : The immunohistochemistry was performed in 72 specimens of gastric carcinomas for evaluating the expression of Wnt-5a, FZD5, GSK3β, axin, CK1, ubiquitin, cyclin D1 and c-myc. Results : There were significant differences for cytoplasm and nucleus ubiquitin for moderately and well differentiated tumors (p=0.03) and for those of the intestinal type of the Lauren classification (p=0.03). The absence of c-myc was related to Lauren's intestinal tumors (p=0.03). Expression of CK1 in the cytoplasm was related to compromised margin (p=0.03). Expression of cyclin D1 protein was more intense in male patients (p=0.03) There was no relation of the positive or negative expression of the Wnt-5a, FZD5, GSK3 and Axin with any clinicopathological variables. Conclusion: The canonical WNT pathway is involved in gastric carcinoma.

RESUMO Racional : Acredita-se que a via Wnt é uma das mais importantes da sinalização envolvidas na carcinogênese gástrica. Objetivos : Analisar a expressão das proteínas das vias Wnt canônicas e não-canônicas no carcinoma gástrico e relacionar sua expressão com as variáveisclinicopatológicas. Método : Foram coletadas 72 amostras de carcinoma gástrico, e áreas representativas do tumor foram selecionadas para o Tissue Microarray. Imunoistoquímica foi realizada para avaliar a expressão de Wnt-5a, FZD5, GSK3β, axina, CK1, ubiquitina, ciclina D1 e c-myc. Resultados : Houve diferenças significativas para a expressão de ubiquitina no citoplasma e núcleo para tumores moderadamente e bem diferenciados (p=0,03) e para aqueles do tipo intestinal da classificação de Lauren (p=0,03). A expressão negativa da proteína c-myc no citoplasma foi relacionada aos tumores intestinais de Lauren (p=0,028). A expressão positiva de CK1 no citoplasma das células neoplásicas foi relacionada a tumores com margens cirúrgicas livre de envolvimento neoplásico (p=0,03). A expressão positiva da proteína ciclina D1 foi maior nos tumores dos homens (p=0,03). Não houve relação da expressão positiva ou negativa das proteínas Wnt-5a e FZD5 no citoplasma ou núcleo com quaisquer variáveis clinicopatológicas. O mesmo foi observado para GSK3β e Axin. Conclusões : A relação da expressão das proteínas da via canônica com as variáveis epidemiológicas e tumorais sugere sua participação na carcinogênese gástrica. Por outro lado, a ausência da relação das expressões das proteínas da via não-canônica sugere sua não participação na carcinogênese gástrica.

Evidence of progenitor cells in the adult human cochlea: sphere formation and identification of ABCG2

OBJECTIVES: The aim of this study was to search for evidence of stem or progenitor cells in the adult human cochlea by testing for sphere formation capacity and the presence of the stem cell marker ABCG2. METHODS: Cochleas removed from patients undergoing vestibular schwannoma resection (n=2) and from brain-dead organ donors (n=4) were dissociated for either flow cytometry analysis for the stem cell marker ABCG2 or a sphere formation assay that is widely used to test the sphere-forming capacity of cells from mouse inner ear tissue. RESULTS: Spheres were identified after 2-5 days in vitro, and the stem cell marker ABCG2 was detected using flow cytometric analysis after cochlear dissociation. CONCLUSIONS: Evidence suggests that there may be progenitor cells in the adult human cochlea, although further studies are required.

Characterization of reactive stroma in prostate cancer: involvement of growth factors, metalloproteinase matrix, sexual hormones receptors and prostatic stem cells

ABSTRACT Introduction and Objectives: Reactive Stroma (RStr) is observed in many human cancers and is related to carcinogenesis. The objectives of the present study were to stablish a relationship of the RStr microenvironment with prostate cancer (Pca) through a morphological and molecular characterization, and to identify a possible relationship between RStr with worse prognosis factors and occurrence of malignant prostatic stem cells. Materials and Methods: Forty prostatic samples were selected from men with Pca diagnosis submitted to radical prostatectomy; they were divided in two groups: Group-1 (n=20): samples without reactive stroma; Group-2 (n=20): samples of PCa with intense stroma reaction. Prostatic samples were evaluated for RStr intensity by Masson Trichromic stain and posteriorly submitted to histopathological and immunohistochemistry analysis for antigens: α-actin, vimentin, IGF-1, MMP-2, FGF-2, C-Myc, PSCA, AR, Erα and ERβ. Results: Reactive stroma with intense desmoplastic reactivity was significantly more frequent in intermediate (Gleason 7, 3+4) and high grade tumors (Gleason 7, 4+3). The group with intense stromal reactivity showed significant higher levels of Vimentin, IGF-1, MMP-2, FGF-2, C-Myc, PSCA and ERα. Conclusions: It can be concluded that RStr may be a predictive marker of Pca progression, since it was associated with increase of growth factors, imbalance of androgen and estrogen receptors and presence of malign prostatic stem cells.

Proteomics analysis of tissue samples from patients with squamous cell carcinoma of the penis and positive to human papillomavirus

ABSTRACTPurpose:The aim of this study was to identify possible protein biomarkers and/or candidates for therapeutic targets in tissues of patients with SCCP, infected by HPV, applying one dimensional electrophoresis (1DE), followed by direct mass spectrometry (MS) analysis.Materials and Methods:Tissues from 10 HPV positive patients with SCCP and from 10 patients with HPV negative non-tumorous penile foreskins were analyzed applying 1D electrophoresis, followed by analysis with direct mass spectrometry (MS).Results:Sixty-three different proteins were identified in the first group and 50 in the second group. Recognition was possible for 28 proteins exclusively detected in Group 1 and 21 proteins presented only in Group 2.Conclusion:Some proteins in the first group are directly involved in the development of other types of cancer, and therefore, suitable for analysis. Complement C3 protein is a strong candidate for evaluating SCCP patients.

Relaciones entre profesionales de la salud y usuarios/as desde la perspectiva de género / Relationships between health care professionals and users from a gender perspective

El objetivo de este artículo es analizar las relaciones entre profesionales de la salud y usuarios/as desde la perspectiva de género. A partir del referencial teórico de Pierre Bourdieu, se retoman y analizan críticamente datos de dos investigaciones realizadas en Brasil de la cuales participamos como autores: la primera, realizada en la ciudad de Río de Janeiro y, la segunda, un estudio multicéntrico y de naturaleza etnográfica desarrollado en ocho servicios distribuidos en cuatro estados brasileños, dos de la región Sudeste y dos de la Nordeste. Entre los principales resultados se destaca que las relaciones entre profesionales de la salud y usuarios/as, aunque estén marcadas por opiniones divergentes, están atravesadas por un habitus "generificado". Se concluye, entre otros aspectos, que la construcción de las diversas feminidades y masculinidades y la forma en que se da el ejercicio de estas en los contextos asistenciales de la salud son producto de un proceso que es, al mismo tiempo, socio-histórico y personal.

The objective of this article is to analyze relationships between health professionals and users from a gender perspective. Using Pierre Bourdieu as a theoretical reference, we critically analyze data from two studies carried out in Brazil in which we took part as authors. The first of these studies was based in Rio de Janeiro and the second was a multicenter and ethnographical study carried out in eight health care facilities distributed throughout four Brazilian states, two in the Southeast region and two in the Northeast region. Among the principal results of the present study, we found that although the relationships between health professionals and users demonstrate varied opinions, all are marked by a gendered habitus. We conclude that, among other aspects, the construction of diverse femininities and masculinities and the way in which these are exercised in health care contexts are the product of process that is both socio-historical and personal.

Tissue expression, serum and salivary levels of vascular endothelial growth factor in patients with HNSCC / Expressão tecidual, soro e níveis salivares de VEGF em pacientes com carcinoma de células escamosas de cabeça e pescoço

Introduction: Vascular endothelial growth factor is thought to be an important angiogenic factor involved in tumor growth, progression, and metastasis. Objective: The present study evaluated the relation between tissue expression, serum and salivary levels of vascular endothelial growth factor in head and neck squamous cell carcinomas, and their correlation with clinicopathologic features. Methods: Samples were collected from 30 patients with head and neck squamous cell carcinomas and 24 healthy volunteers. Immunohistochemical analysis was used for tissue expression and enzyme-linked immunosorbent assay was employed to measure serum and salivary levels. Results: No vascular endothelial growth factor staining was observed in normal tissues, whereas vascular endothelial growth factor expression was seen in 6 patients (20%). Mean serum level of VEGF was 83.7 ± 104.47 in patients and 50.04 ± 32.94 in controls. Mean salivary level of vascular endothelial growth factor was 174.41 ± 115.07 in patients and 149.58 ± 101.88 in controls. No significant difference was found by Mann-Whitney test between controls and patients (p = 0.411, p = 0.944, respectively). No correlation was found between vascular endothelial growth factor tissue expression and its serum and salivary level. Conclusion: Overexpression of vascular endothelial growth factor was found in head and neck squamous cell carcinoma patients, suggesting its role in the pathogenesis of head and neck squamous cell carcinoma, but no relation was found between tissue expression, serum levels, and salivary levels of this marker. .

Introdução: Acredita-se que o fator de crescimento vascular endotelial (FCEV) seja um importante fator angiogênico envolvido no crescimento, na progressão e na metástase tumoral. Objetivo: O presente estudo avalia a relacão entre a expressão tecidual e os níveis séricos e salivares do FCEV em carcinomas de células escamosas da cabeca e pescoco (CCECPs) e sua correlacão com aspectos clinicopatológicos. Método: Foram coletadas amostras de 30 pacientes com CCECP e de 24 voluntários saudáveis. Utilizamos análise imuno-histoquímica para a expressão tecidual e ELISA para determinação dos níveis séricos e salivares. Resultados: Não foi observada coloração para FCEV nos tecidos normais, enquanto que foi observada expressão de FCEV em seis pacientes (20%). O nível sérico médio de FCEV foi 83,7 ± 104,47 em pacientes e 50,04 ± 32,94 em controles. O nível salivar médio de FCEV foi de 174,41 ± 115,07 em pacientes e 149,58 ± 101,88 em controles. Não foi observada diferenca significativa pelo teste de Mann-Whitney entre controles e pacientes (respectivamente, p = 0,411, p = 0,944). Não foi observada relacão entre a expressão tecidual de FCEV e seus níveis séricos e salivares. Conclusão: A expressão elevada de FCEV foi observada em pacientes com CCECP, e isso sugere seu papel na patogênese de CCECP, mas não foi observada relacão entre a expressão tecidual e os níveis séricos e salivares desse marcador. .

Genetic polymorphisms and asthma: findings from a case - control study in the Madeira island population

BACKGROUND: Asthma is a complex disease influenced by multiple genetic and environmental factors. While Madeira has the highest prevalence of asthma in Portugal (14.6%), the effect of both genetic and environmental factors in this population has never been assessed. We categorized 98 asthma patients according to the Global Initiative for Asthma (GINA) guidelines, established their sensitization profile, and measured their forced expiratory volume in 1second (FEV1) and forced vital capacity (FVC) indexes. Selected single nucleotide polymorphisms (SNPs) were analysed as potential markers for asthma susceptibility and severity in the interleukin 4 (IL4), interleukin 13 (IL13), beta-2-adrenergic receptor (ADRB2), a disintegrin and metalloprotease 33 (ADAM33), gasdermin-like (GSDML) and the signal transducer and activator of transcription 6 (STAT6) genes comparatively to a population reference set. RESULTS: Although mites are the major source of allergic sensitization, no significant difference was found amongst asthma severity categories. IL4-590*CT/TT and IL4-RP2*253183/183183 were found to predict the risk (2-fold) and severity (3 to 4-fold) of asthma and were associated with a lower FEV1 index. ADRB2-c.16*AG is a risk factor (3.5-fold), while genotype GSDML-236*TT was protective (4-fold) for moderate-severe asthma. ADAM33-V4*C was associated to asthma and mild asthma by the transmission disequilibrium test (TDT). Finally, ADAM33-V4*CC and STAT6-21*TT were associated with higher sensitization (mean wheal size ≥10mm) to house dust (1.4-fold) and storage mite (7.8-fold). CONCLUSION: In Madeira, IL4-590C/T, IL4-RP2 253/183, GSDML-236C/T and ADAM33-V4C/G SNPs are important risk factors for asthma susceptibility and severity, with implications for asthma healthcare management.

Thymosin ß4 expression in colorectal polyps and adenomas

OBJECTIVE: Thymosin beta 4 (Tβ4) is a ubiquitous peptide that plays pivotal roles in the cytoskeletal system and in cell differentiation. Recently, a role for Tβ4 has been proposed in experimental and human carcinogenesis, including gastrointestinal cancer. This study was aimed at evaluating the relationship between Tβ4 immunoreactivity and the initial steps of carcinogenesis. METHODS: In total, 60 intestinal biopsies, including 10 hyperplastic polyps, 10 sessile serrated adenomas/polyps, 15 colorectal adenomas with low-grade dysplasia, 15 adenomas with high-grade dysplasia, 15 adenocarcinomas and 10 samples of normal colon mucosa, were analyzed for Tβ4 expression by immunohistochemistry. RESULTS: Weak cytoplasmic reactivity for Tβ4 was detected in the normal colon mucosa. No reactivity for Tβ4 was found in hyperplastic and sessile serrated polyps/adenomas. Tβ4 expression was observed in 10/15 colorectal adenocarcinomas. In adenomas with low-grade dysplasia, Tβ4 immunoreactivity was mainly detected in dysplastic glands but was absent in hyperplastic glands. Tβ4 immunoreactivity was characterized by spot-like perinuclear staining. In high-grade dysplastic polyps, immunostaining for Tβ4 appeared diffuse throughout the entire cytoplasm of dysplastic cells. Spot-like perinuclear reactivity was detected in adenocarcinoma tumor cells. CONCLUSIONS: Our study shows for the first time that Tβ4 is expressed during different steps of colon carcinogenesis. The shift of Tβ4 immunolocalization from low-grade to high-grade dysplastic glands suggests a role for Tβ4 in colorectal carcinogenesis. However, the real meaning of Tβ4 reactivity in dysplastic intestinal epithelium remains unknown. .

Micrometástasis: estrategias para su detección / Micrometastases: strategies for detection

La micrometástasis o enfermedad mínima residual ha adquirido una importancia trascendental en oncología al representar un verdadero problema clínico que debe ser solucionado, ya que aún se desconoce la respuesta de estos focos tumorales a los diferentes tratamientos que se usan para el control del cáncer. Aun cuando este es un problema específico fundamental a ser solucionado, ya existen métodos de ensayo inmunohistoquímicos y de biología molecular, que han permitido la ubicación de microfocos de células tumorales en diferentes órganos y tejidos, existiendo diferentes técnicas para determinar y cuantificar estas lesiones. Dentro de estas técnicas destacan la citometría de flujo y diferentes técnicas moleculares que van desde las ya tradicionales hasta las más nuevas y sofisticadas. El objetivo de la presente revisión está dirigido evaluar los nuevos métodos de diagnóstico que permitan la identificación de esta enfermedad residual, lo cual serviría para establecer tratamientos individualizados que pudieran prevenir la recurrencia de la enfermedad en los pacientes de cáncer bajo tratamiento.

Micrometastasis or minimal residual disease has become critically important in oncology since it represents a true clinical problem that must be solved, as the response of these tumor foci to the different treatments that are used for the control of cancer, is still unknown. Even though this is a fundamental specific problem to be solved, there are already immunohistochemical and molecular biology diagnostic methods that have allowed microfoci location of tumor cells in various organs and tissues, and different techniques are available to determine and quantify these lesions. Within these techniques, flow cytometry and different molecular methods are included, and they range from the traditional to the newest and most sophisticated. The goal of this review was aimed to evaluate new diagnostic methods that permit the identification of this residual disease, which would serve to establish individualized treatments and prevent the recurrence of the disease in cancer patients under treatment.

Differencial proteome of clear-cell renal cell carcinoma (ccRCC) tissues

Purpose We attempted to detect, for the first time in a Brazilian cohort, differences in protein expression between clear-cell renal cell carcinoma (ccRCC) and their normal adjacent tissues, aiming to identify biomarkers and/or therapeutic target candidates for this disease. Material and Methods Twenty-four ccRCC and adjacent normal tissues were collected after surgery and their protein extracts were quantified, pooled and separated by two-dimensional polyacrylamide gel electrophoresis (2DE), followed by statistical analysis of the stained gels. Spots of interest were excised from the gels, digested with trypsin and identified by MALDI-TOF-TOF mass spectrometry. Results Twenty-six differential spots were detected between the two classes of tissues, among which twenty were identified by mass spectrometry and sixteen were found to be non-redundant. Eleven proteins were either underexpressed or undetected in the ccRCC extracts, such as prohibitin and peroxiredoxin-3, whereas five were found to be overexpressed or exclusively detected in the ccRCC extract, including αβ crystalin and heat shock protein 27. CONCLUSIONS Several proteins were detected at differential levels when compared to normal adjacent tissues, and, moreover, many have been previously described by their relationship with RCC. Therefore, this work corroborates previous reports on the search for biomarkers for ccRCC, as well as it points out new candidates that may be validated in future studies. .

Expressão da proteína ligadora de cálcio S100 A7 (psoriasina) no carcinoma laríngeo / Expression of calcium binding protein S100 A7 (psoriasin) in laryngeal carcinoma

Muitos estudos relatam o aumento da expressão de S100 A7 (psoriasina) em lesões neoplásicas. Destacam-se trabalhos em carcinoma da mama, espinocelular da bexiga, pele e cavidade oral. Não foi demonstrada expressão da S100 A7 em câncer de laringe. OBJETIVO: Identificar a expressão da proteína ligadora de cálcio S100 A7 e sua correlação com carcinomas espinocelular da laringe. MATERIAL E MÉTODOS: Amostras de tecido neoplásico de 63 pacientes foram submetidos à imunohis toquímica com o anticorpo S110 A7. Os resultados foram classificados e comparados. RESULTADOS: O grupo bem diferenciado teve a maior pontuação de falha no tratamento. O grupo moderadamente diferenciado apresentou escores mais elevados do que o grupo pouco diferenciado. Pontuações mais altas predominaram nos estágios I e II no grupo moderadamente diferenciado, enquanto a distribuição do escore foi mais homogênea em estados avançados (III e IV). Em relação às falhas no tratamento, o grupo pontuação zero (04/03 complicações: 75%) diferiu significativamente da pontuação restante (13/59: 22%). CONCLUSÕES: A S100 A7 foi expressa em 93,7% dos casos de câncer de laringe, com maior positividade nos tumores mais diferenciados e taxa significativamente menor de falha no tratamento. A pontuação obtida não teve impacto sobre a sobrevivência.

Many studies have reported increased expression of S100 A7 (psoriasin) in neoplastic lesions. Among them are studies on breast carcinoma, bladder squamous cell carcinoma, skin tumors and oral cavity squamous cell carcinoma. The expression of S100 A7 has not been described for laryngeal cancer. OBJECTIVE: This study aims to identify the expression of the calcium-binding protein S100 A7 and its correlation with squamous cell carcinomas of the larynx. MATERIAL AND METHODS: Specimens from 63 patients were submitted to immunohistochemistry testing with antibody S100 A7. Results were classified and compared. RESULTS: The group with highly differentiated tumors had the highest treatment failure scores. Moderately differentiated tumors had higher treatment failure scores than poorly differentiated tumors. Higher scores were predominantly seen on stages I and II in moderately differentiated tumors, whereas score distribution was more homogeneous in advanced stage disease (III and IV). Regarding failure in treatment, the group scoring zero (3/4 complications: 75%) differed significantly from the remaining groups (13/59: 22%). CONCLUSIONS: S100 A7 marker was expressed in 93.7% of laryngeal cancer cases, with higher positive correlation rates in more differentiated tumors and significantly lower rates of treatment failure. Scores had no impact on survival rates.

Foxp3 expression is associated with aggressiveness in differentiated thyroid carcinomas

OBJECTIVES: Forkhead box P3 (FoxP3) expression has been observed in human cancer cells but has not yet been reported in thyroid cells. We investigated the prognostic significance of both FoxP3 expression and intratumoral FoxP3+ lymphocyte infiltration in differentiated thyroid carcinoma cells. METHODS: We constructed a tissue microarray with 385 thyroid tissues, including 266 malignant tissues (from 253 papillary thyroid carcinomas and 13 follicular carcinomas), 114 benign lesions, and 5 normal thyroid tissues. RESULTS: We determined the expression of FoxP3 in both tumor cells and tumor-infiltrating lymphocytes using immunohistochemical techniques. Cellular expression of FoxP3 was evident in 71% of benign and 91.9% of malignant tissues. The nuclear and cytoplasmic expression patterns were quantified separately. A multivariate logistic regression analysis indicated that cytoplasmic FoxP3 expression is an independent risk factor for thyroid malignancy. Cytoplasmic FoxP3 staining was inversely correlated with patient age. Nuclear FoxP3 staining was more intense in younger patients and in tumors presenting with metastasis at diagnosis. FoxP3+ lymphocytes were more frequent in tumors smaller than 2 cm, those without extrathyroidal invasion, and in patients with concurrent chronic lymphocytic thyroiditis. CONCLUSIONS: We demonstrated FoxP3 expression in differentiated thyroid carcinoma cells and found evidence that this expression may exert an important influence on several features of tumor aggressiveness.

Vimentin expression and the influence of Matrigel in cell lines of head and neck squamous cell carcinoma

Vimentin is a cytoeskeletal intermediate filament protein commonly observed in mesenchymal cells; however, it can also be found in malignant epithelial cells. It is demonstrated in several carcinomas, such as those of the cervix, breast and bladder, in which it is widely used as a marker of the epithelial to mesenchymal transition that takes place during embryogenesis and metastasis. Vimentin is associated with tumors that show a high degree of invasiveness, being detected in invasion front cells. Its expression seems to be influenced by the tumor microenvironment. The aim of this study was to evaluate vimentin expression in head and neck squamous cell carcinoma (HNSCC) cell lines, and to investigate the contribution of the microenvironment to its expression. HNSCC cell lines (HN6, HN30 and HN31) and an immortalized nontumorigenic cell line (HaCaT) were submitted to a three-dimensional assay with Matrigel. Cytoplasmatic staining of the HN6 cell line cultured without Matrigel and of the HN30 and HN31 cell lines cultured with Matrigel was demonstrated through immunohistochemistry. Western Blotting revealed a significant decrease in vimentin expression for the HN6 cell line and a significant increase for the HN30 and HN31 cell lines cultured with Matrigel. The results suggest that vimentin can be expressed in HNSCC cells and its presence is influenced by the microenvironment of a tumor.

A murine model of xenotransplantation of human glioblastoma with imunosupression by orogastric cyclosporin / Modelo murino de xenotransplante de glioblastoma humano com imunossupressão utilizando ciclosporina orogástrica

Several animal experimental models have been used in the study of malignant gliomas. The objective of the study was to test the efficacy of a simple, reproducible and low cost animal model, using human cells of glioblastoma multiforme (GBM) xenotransplantated in subcutaneous tissue of Wistar rats, immunosuppressed with cyclosporin given by orogastric administration, controlled by nonimunosuppressed rats. The animals were sacrificed at weekly intervals and we have observed gradual growth of tumor in the immunosuppressed group. The average tumor volume throughout the experiment was 4.38 cm³ in the immunosuppressed group, and 0.27 cm³ in the control one (p<0.001). Tumors showed histopathological hallmarks of GBM and retained its glial identity verified by GFAP and vimentin immunoreaction. Immunosuppression of rats with cyclosporin was efficient in allowing the development of human glioblastoma cells in subcutaneous tissues. The model has demonstrated the maintenance of most of the histopathological characteristics of human glioblastoma in an heterotopic site and might by considered in research of molecular and proliferative pathways of malignant gliomas.

Vários modelos animais têm sido avaliados no estudo dos gliomas e até o momento nenhum pôde ser considerado ideal. O objetivo deste trabalho é verificar a eficácia de um modelo animal simples, reprodutível e de baixo custo. Utilizamos células humanas de glioblastoma multiforme (GBM) xenotransplantadas em ratos Wistar, submetidos a imunossupressão com ciclosporina administrada por via orogástrica. Células tumorais foram implantadas no tecido subcutâneo dos ratos imunossuprimidos com ciclosporina, sendo o controle feito em ratos não imunossuprimidos. Os animais foram sacrificados em intervalos semanais e foi observado crescimento progressivo do tumor no grupo imunossuprimido. A média do volume tumoral em todo o experimento foi de 4,38 cm³ no grupo imunossuprimido e 0,27 cm³ no grupo controle (p<0,001). Os tumores apresentavam características histopatológica do GBM e mantinham sua identidade glial, verificadas por imunoreação para GFAP e vimentina. A imunossupressão dos ratos com ciclosporina foi eficiente em permitir o desenvolvimento do glioblastoma no tecido subcutâneo. Uma vez que o presente modelo mantém a maioria das características histopatológicas do glioblastoma humano, ele pode ser considerado em estudos que avaliem as vias moleculares e proliferativas dos gliomas malignos.

Melanoma de tipo animal / Animal-type melanoma

Lo que se ha dado en llamar melanoma de tipo animal es un tumor aún no bien determinado ni clasificado. Tiene similitudes clínicas e histopatológicas con el melanoma que se observa en los caballos de pelaje tordillo: un infiltrado alarmante, denso y extenso, de células que ocupan toda la dermis y aún el celular subcutáneo, acompañado sin embargo de un pronóstico benigno y larga sobrevida. El nombre propuesto por Zembowicz et ál., melanocitoma epitelioide pigmentado, parece más adecuado para esta rara variante de melanoma.

Animal-type melanoma is a rare distinct variant of melanoma, charac-terized by a dense proliferation of epithelioid and spindle-shaped mela-nocytes occupying the dermis and the hypodermis, and resembles theheavily pigmented melanomas as seen in grey horses. Only a limitednumber of cases have been reported and, as such, the clinical character-istics of this melanoma variant are incompletely understood. Despite thehigh mean thickness of the tumors, reports indicate a less aggressive behavior and a better outcome of this tumor when compared with conven-tional melanoma, but the underlying pathways related to this particularoutcome are still unknown. As proposed by Zembowicz et ál., the term‘pigmented epithelioid melanocitoma’ seems much more suitable.

Expressão da aromatase em carcinomas de mama ductais invasivo e in situ presentes na mesma mama / Aromatase expression in invasive and in situ ductal carcinoma present in the same breast

OBJETIVO: Avaliar expressão da enzima aromatase nos carcinomas de mama ductais invasivos (CDI), in situ (CDIS), no epitélio e estromas adjacentes. MÉTODOS: Foram avaliados 45 espécimes cirúrgicos provenientes de mastectomias e quadrantectomias com CDI e CDIS concomitantes de pacientes com estadios clínicos I e II. A análise da expressão da enzima aromatase foi realizada por meio de anticorpos policlonais antiaromatase e categorização das amostras de acordo com intensidade e número de células coradas. RESULTADOS: Nos 45 casos de CDI a expressão da aromatase foi positiva em 32 espécimes (71 por cento) e negativa em 13 (29 por cento). Nos casos de CDIS, a positividade foi idêntica à observada no CDI, mostrando correlação positiva. No epitélio normal constatou-se expressão positiva em 19 casos (42,2 por cento) e negativa nos outros 26 (57,8 por cento), mostrando correlação positiva estatisticamente (p<0,01), quando comparada com CDI e CDIS. Na análise do estroma normal a expressão da aromatase foi observada em apenas sete (15,5 por cento) dos 45 casos avaliados, não apresentando correlação com nenhuma variável analisada para expressão da aromatase. A presença da aromatase no estroma tumoral foi positiva em 36 casos (80 por cento) e negativa em 9 (20 por cento), mostrando correlação estatisticamente com a expressão no CDI (p<0,01) e no CDIS (p<0,01). Ao se comparar a expressão da aromatase no CDI, CDIS, epitélio normal e estroma tumoral com os graus nuclear e histológico, tamanho tumoral e idade da paciente, não foram encontradas diferenças estatisticamente significantes. CONCLUSÃO: Os resultados revelaram alta correlação entre expressão da aromatase no CDI, CDIS, epitélio normal e estroma tumoral, sugerindo possível mecanismo de ação autócrina e parácrina desta enzima na gênese do câncer de mama.

OBJECTIVE: to evaluate the expression of aromatase in simultaneously invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS). METHODS: forty-five surgical samples were obtained from mastectomy and quadrantectomy with simultaneous IDC and DCIS of stage I and II patients. Aromatase was evaluated using antibodies anti-aromatase and the samples classified in accordance with the number and intensity of stained cells. RESULTS: Aromatase was expressed positively in 32(71 percent) and negatively in 13(29 percent) of the cases in the IDC. The same results were obtained in the DCIS showing a perfect positive correlation. In the normal epithelium,aromatase was positive in 19(42.2 percent) and negative in 26 (57.8 percent) and a positive correlation, statistically significant was obtained when compared with IDC and DCIS(p<0.01). Concerning the normal stroma, positivity was only 7 (15.5 percent) showing no correlation with aromatase expression. Aromatase was positive in 36(80 percent) of the tumor stroma and this result was statistically significant as in the IDC and DCIS. Comparing results of aromatase expression with nuclear grade, histological grade, tumor size and age no difference was found. CONCLUSION: our results demonstrated high correlation between aromatase expression in IDC, DCIS, normal epithelium and tumor stroma showing a possible autocrine and paracrine mechanism of this enzyme in breast cancer.

Influence of feeder layer on the expression of stem cell markers in cultured limbal corneal epithelial cells.

BACKGROUND & OBJECTIVE: The limbus is enriched with the stem cells of corneal epithelium. Auto- and allograft limbal transplantations are effective in restoring the corneal epithelium and inhibiting inflammation and neovascularization. Preserved human amniotic membrane (AM) is now widely used as a substrate for ocular surface reconstruction. The combination of limbal and AM transplantation has been shown to improve the surgical outcome in patients with total limbal stem cell deficiency (LSCD). The purpose of this study was to compare the expression of putative stem cell markers ATP binding cassette protein (ABCG2) and keratinocyte stem cell marker: p63 and differentiation markers. (connexin 43 and keratin 3 / keratin 12) on the limbal epithelial cells cultured over the denuded AM with and without the 3T3 murine fibroblast cells as feeder layer. METHODS: Human limbal tissues obtained from the cadaveric donor eyes were cultured over the denuded human amniotic membrane in the presence of mitomycin C treated 3T3 fibroblasts and the cultured cells studied for the expression of ABCG2 and p63 by immunohistochemistry and Western blot. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was done on the cultured cells at varying intervals of time for expression of ABCG2, p63, connexin43 (Cnx43), and keratin 3 (K3) and keratin 12 (K12). RESULTS: The growth rates were similar in both denuded AM and denuded AM + 3T3. The cells cultured over AM + 3T3 showed the expression of p63 and ABCG2 till 21 days of incubation by immunohistochemistry and Western blot. The expression of p63 and ABCG2 were retained till 21 days of incubation on the cells cultured over denuded AM + 3T3, whereas it was expressed only till day 8 on the cells cultured over the denuded membrane by semi quantitative RT-PCR. Cnx43 and K3/K12 were observed in both the conditions. INTERPRETATION & CONCLUSION: The limbal epithelial cells cultured in the presence of mitomycin C treated 3T3 feeder layer were able to maintain the expression of putative stem cell markers. Further in vitro studies using feeder layer will enable us to understand the factors, which play a role in maintaining the limbal stem cell niche.

Evaluación por inmunohistoquímica de la expresión de hormonas hipofisiarias y del marcador de proliferación celular Ki-67 en tejido de adenomas causantes de acromegalia / Immunohistochemistry for pituitary hormones and Ki-67 in growth hormone producing pituitary adenomas

Background: Growth hormone (GH) producing adenomas, frequently express several hormones. This condition could confer them a higher proliferative capacity. Ki-67 is a nuclear protein antigen that is a marker for proliferative activity. Aim: To measure the immunohistochemical hormone expression in pituitary adenomas, excised from patients with acromegaly. To determine if the pluríhormonal condition of these adenomas is associated with a higher proliferative capacity, assessed through the expression of Ki-67. Material and methods: Forty one paraffin embedded surgical samples of pituitary adenomas from patients with acromegalia were studied. Immunohistochemistry for GH, prolactin (PRL), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), adrenocorticotropin (ACTH) and for the expression of Ki-67 was carried out. Results: All samples were positive for GH. Twenty seven had positive staining for PRL, 12 had positive staining for glycoproteic hormones and 11 for PRL and one or more glycoproteic hormones. Mean staining for Ki-67 was Z.6±3.3 percent. There were no differences in the expression of this marker between mono or pluríhormonal tumors. The expression was neither associated with extrasellar extensión. Conclusions: Half of GH producing pituitary adenomas are pluríhormonal. There are no differences in the expression of Ki-67 between mono and plurihormonal adenomas.

Immunohistochemical Analysis of Non-Small Cell Lung Cancer: Correlation with Clinical Parameters and Prognosis

Non-small cell lung cancers (NSCLC) vary in their biologic behavior. Recurrence and tumor-related mortality may be attributable to molecular abnormalities in primary tumors. This study evaluated such immunophenotypes with regard to cell cycle regulation and proliferation, apoptosis, and angiogenesis, to determine their significance for patient outcome. Core biopsies from 219 patients with NSCLC were assembled on tissue microarrays, and the expressions of p16, p21, p27, cyclin B1, cyclin E, Ki-67, caspase-3, survivin, bcl-2, VEGF, and endostatin were evaluated by immunohistochemistry. Despite previously described prognostic relevance of some of the investigated molecules, many of those markers were not directly associated with recurrence or survival. However, there was a trend for p16 immunoreactivity to be associated with a good prognosis (57% vs. 42% in 5-yr survival) (p=0.071). bcl-2 expression was strongly correlated with a better outcome (65% vs. 45% in 5-yr survival) (p=0.029), and the hazard of death for bcl-2 positive patients was 0.42 times of that for bcl-2 negative patients (p=0.047). A multivariate analysis with Cox proportional hazards model confirmed that the lymph node status (p=0.043) and stage (p=0.003) were other independent prognostic factors. Our results suggest that p16 and bcl-2 provide prognostic information independent of the TNM stage in NSCLC.

Cultivation of human corneal limbal stem cells in Mebiol gel--A thermo-reversible gelation polymer.

BACKGROUND & OBJECTIVES: Cultivated limbal stem cell transplantation is being used as a current treatment modality for limbal stem cell deficiency. However, use of allogenic biological material as substrate is associated with risks of transmission of certain diseases and allograft rejection. Therefore development of non-toxic biodegradable synthetic polymers is important. We undertook this study to evaluate the use of a synthetic polymer Mebiol gel as a substrate for the growth of limbal phenotype cells and cornea phenotype cells from limbal explants. METHODS: Human cadaveric limbal explants cells were cultivated on Mebiol gel. The proliferative capacity of cultivated cells was analyzed with thymidine incorporation studies. Immunostaining for presumed limbal stem cell association markers and cornea differentiation markers was performed and confirmed with reverse transcription (RT-PCR). RESULTS: The limbal explants underwent proliferation in vitro. The cultivated cells expressed the presumed limbal stem cell association markers (ABCG2 and p63), the transient amplifying cell markers (connexin 43, integrin alpha9) and the cornea differentiation marker (K3). RT PCR confirmed the immunohistochemical data. INTERPRETATION & CONCLUSION: Our findings showed that the synthetic polymer Mebiol gel was able to support limbal explant proliferation. The cultured cells expressed presumed limbal stem cell association markers, transient amplifying cells and cornea phenotype markers. Mebiol Gel can be used as a scaffold for growing limbal explants.