Análisis inmunohistoquímico de MMP-1, MMP-2 y MMP-9 en ameloblastoma convencional / Immunohistochemical analysis of MMP-1, MMP-2, MMP-9 in conventional ameloblastoma

Introducción: las metaloproteinasas son enzimas que participan en la remodelación tisular y su función se relaciona con procesos fisiológicos y patológicos, como la invasión y la metástasis. El ameloblastoma convencional (AMC) es una neoplasia epitelial benigna odontogénica intraósea caracterizada por una progresión lenta y localmente invasiva, cuyo crecimiento se ha vinculado con el recambio ósea y la remodelación de la matriz extracelular. El objetivo del presente trabajo fue determinar la presencia inmunohistoquímica de MMP-1, MMP-2 y MMP-9 en el AMC. Material y métodos: se realizó un estudio piloto observacional analítico utilizando cinco muestras de AMC. Los especímenes fueron recolectados aleatoriamente del archivo del Departamento de Patología Oral y Maxilofacial, de la Escuela Nacional de Estudios Superiores (ENES) Unidad León, UNAM. Como grupo control se emplearon dos especímenes de folículo dental, obtenido de pacientes con indicación de su extracción por motivos ortodóncicos. Se realizó la técnica de inmunohistoquímica por peroxidasa, recolectando el nivel y proporción de inmunoexpresión de manera semicuantitativa. Resultados: cuatro pacientes fueron de género masculino y uno femenino, la edad promedio fue de 40.6 ± 14.9 años. Todas las muestras fueron obtenidas de la región mandibular posterior. Se observaron dos especímenes con patrón folicular y tres con plexiforme. Las MMP-2 y MMP-9 se detectaron sólo en uno de los cinco especímenes y únicamente en el parénquima de la lesión, con una proporción de 100%. Conclusión: según nuestro análisis inmunohistoquímico, las MMP-2 y MMP-9 son las metaloproteinasas que presentaron expresión positiva dentro de la patogénesis del AMC comparado a la MMP-1; no obstante, es necesario realizar este tipo de estudios en una población mayor (AU)

Introduction: metalloproteinases are enzymes involved in tissue remodeling and their function is related to physiological and pathological processes, such as invasion and metastasis. These enzymes are capable of degrading components of the extracellular matrix, which may promote tumor progression. Conventional ameloblastoma (CA) is described as a benign intraosseous epithelial odontogenic neoplasm characterized by a slow and locally invasive progression, whose growth has been linked to bone turnover and extracellular matrix remodeling. The aim of the present work was to determine the immunohistochemical presence of MMP-1, MMP-2 and MMP-9 in CA. Material and methods: an analytical observational pilot study was performed using 5 CA, randomly collected from the archive of the Department of Oral and Maxillofacial Pathology, Escuela Nacional de Estudios Superiores (ENES) Unidad León, UNAM. The control group used were two dental follicle samples, obtained from patients with extraction indication for orthodontic treatment. The peroxidase immunohistochemistry assay was performed, collecting semiquantitatively level and proportion of immunoexpression. Results: four patients were male and one female, the average age was 40.6 ± 14.9 years. All specimens were obtained from the posterior mandibular region. Two specimens were observed with follicular pattern and three with plexiform pattern. MMP-2 and MMP-9 were detected only in one of the five specimens, with presence in the parenchyma of the lesion, with a proportion of 100% of the cell analyzed. Conclusion: according to our immunohistochemical analysis, MMP-2 and MMP-9 are the metalloproteinases that presented positive expression within the pathogenesis of CA compared to MMP-1; however, it is necessary to perform this type of studies in a larger population (AU)

Diagnóstico de precisão das lesões mamárias / Accurate diagnosis of breast lesions

PONTOS-CHAVE As lesões mamárias compreendem uma ampla variedade de diagnósticos que apresentam comportamentos diversos. As lesões mamárias podem ser classificadas como lesões benignas, de potencial de malignidade indeterminado (B3), carcinoma in situ e carcinoma invasor. Na era da medicina personalizada, individualizar e obter um diagnóstico preciso faz grande diferença no desfecho final da paciente, principalmente no caso do câncer de mama. Exames de imagem direcionados e de qualidade, métodos de biópsia adequadamente selecionados e análises de anatomopatologia convencional, imuno-histoquímica e até molecular são determinantes no diagnóstico e no manejo das pacientes.

Variability in the Epithelial Expression of Ki67 and Polarization Characteristics of Collagen in Odontogenic Cysts and Tumours

ABSTRACT Objective: To assess the proliferation of epithelium (using the Ki67 index) and the polarization pattern of collagen in selected odontogenic cysts and tumours. In addition, an exploratory analysis of the effect of inflammation on the proliferation rate was done. Material and Methods: Following immunohistochemical staining, the labelling/proliferation index of Ki67 was calculated. The thickness and corresponding polarization colour of 100 juxta-epithelial picrosirius red-stained collagen fibers were assessed using linear micrometry with an eyepiece reticule under × 1000 magnification. Inflammation was graded subjectively as mild, moderate, and severe. Results: Overall Ki-67 expression was higher in the radicular cyst, Odontogenic Keratocyst, Ameloblastoma, while suprabasal Ki-67 positivity was maximum in Odontogenic Keratocyst. The stromal collagen fibers in Ameloblastoma showed predominantly green birefringence, whereas Odontogenic Keratocyst had orange birefringence. There was no significant association of inflammation with Ki-67 expression or birefringence patterns. Conclusion: The highest Ki67 expression in the radicular cyst, followed by Odontogenic Keratocyst and Ameloblastoma. Differences in the collagen maturation pattern were noted innately in five lesions studied and were further influenced by inflammatory changes. Epithelial proliferation and concomitant expression of thickness and maturity of the stromal collagen are innate features of the lesion further influenced by inflammation in various odontogenic cysts and tumours and may, in turn, guide the clinical behavior.

Comparative Assessment of E-cadherin's Expression between the Metastatic and Non-metastatic Oral Squamous Cell Carcinoma: An Immunohistochemical Study

ABSTRACT Objective: To identify the clinicopathological correlation of E-cadherin expression in metastatic and non-metastatic oral squamous cell carcinoma (OSCC). Material and Methods: A total of 90 paraffin-embedded tissue sections of OSCC were retrieved from the registry. The total selected samples were 45 cases each from the primary lesions of metastatic and non-metastatic OSCC. One section was subjected to routine Hematoxylin and eosin stain and another to immunohistochemical analysis for E-cadherin expression. Results: A non-significant (p˃0.05) increased expression is seen in the non-metastatic group compared to the metastatic group, with predominantly membrane as the staining site in either group. However, the expression of E-cadherin did not reveal any statistically significant association with independent variables such as age, gender, and adverse habits of the patients (p>0.05). On the other hand, with respect to the histological differentiation of OSCC, a significant association (p<0.001) was observed with the well-differentiated type of metastatic OSCC. Conclusion: E-cadherin was useful to some extent in predicting regional metastasis. However, further studies using a panel of biomarkers with increased sample size may help us understand the process involved in metastasis.

¿Cuándo el patólogo debe solicitar inmunomarcación con B-Catenina?: una revisión de la literatura a propósito de dos casos / When should the pathologist request immunostaining with B-catenin?: a review of the literature on two cases

For more than 20 years, immunohistochemistry has represented an auxiliary test of great relevance to support pathological work, however, it should be noted that the pillar of diagnosis continues and will continue to be the classic morphological description based on hematoxylin eosin and the trained eye of the specialist. In neoplastic pathologies, whether benign or malignant, it is becoming increasingly necessary to incorporate new tissue biomarkers that help objectify or confirm the diagnosis of each patient, in order to provide better treatment or a more precise diagnosis about the biological nature of their illness. In this line, there has been intense research in relation to the participation of the Wnt/ß-catenin pathway in the development of various types of tumors, including colon adenocarcinoma, some pancreatic neoplasms and even some tumors of mesenchymal origin, as will be seen. in this work. In this context and based on two clinical cases of special interest, we have prepared a brief review of the literature considering the biological aspects of ß-catenin, tumors where there is currently a true relative consensus that its immunolabeling offers a real contribution to the confirmation of the entity and finally a limited exposition regarding the future of this biomarker in the pathology discipline.

Desde hace más de 20 años la inmunohistoquímica ha representado una prueba auxiliar de gran relevancia para apoyar el trabajo anatomopatológico, no obstante, cabe señalar que, aún el pilar del diagnóstico sigue y seguirá siendo la descripción morfológica clásica basada en hematoxilina eosina y el ojo entrenado del especialista. En las patologías neoplásicas, ya sea benignas, como malignas, se hace cada vez más necesario la incorporación de nuevos biomarcadores tisulares que ayuden a objetivar o confirmar el diagnóstico de cada paciente, con objeto de entregar un mejor tratamiento o un diagnóstico más preciso de la naturaleza biológica de su enfermedad. En esta línea, ha habido intensa investigación en relación con la participación de la vía Wnt/ß-catenina en el desarrollo de varios tipos de cáncer, entre ellos el adenocarcinoma de colon, algunas neoplasias pancreáticas e incluso algunos tumores de origen mesenquimal como se verá en este trabajo. En este contexto y partir de dos casos clínicos de especial interés, hemos preparado una breve revisión de la literatura considerando los aspectos biológicos de la ß-catenina, los tumores donde en la actualidad existe verdadero consenso de que su inmunomarcación ofrece un aporte real a la confirmación de la entidad y finalmente una exposición acotada respecto al futuro de este biomarcador en la disciplina de la anatomía patológica.

Recorrência do ameloblastoma: análise de fatores clínicoradiográficos e imunoexpressão de hMSH2, hMLH1 e KI-67 / Ameloblastoma recurrence: analysis of clinical-radiographic factors and immunoexpression of hMSH2, hMLH1 and KI-67

Introdução: O ameloblastoma é uma neoplasia odontogênica benigna, que apresenta altas taxas de recorrência pós-operatória. Diversos estudos mostram a relação entre as características clínico-patológicas e as modalidades de tratamento na recorrência do ameloblastoma. Os mecanismos moleculares envolvidos com a etiopatogenia deste tumor são pouco conhecidos, e apesar de alterações no Sistema Mismatch favorecerem o desenvolvimento de diferentes neoplasias humanas, a importância destes no desenvolvimento do ameloblastoma ainda permanece pouco compreendido. Objetivo: Identificar os fatores clínico-patológicos associados à recorrência do ameloblastoma, bem como investigar o papel da imunoexpressão das proteínas hMLH1, hMSH2 e Ki-67 na recidiva desses tumores odontogênicos. Metodologia: Tratou-se de um estudo descritivo, transversal e restrospectivo, com uma amostra constituída por 22 casos de ameloblastomas recidivantes e 22 casos não-recidivantes. A análise imunoistoquímica foi realizada de forma quantitativa, considerando a localização celular (nuclear) das proteínas estudadas. O teste de McNemar foi utilizado para comparar as variáveis entre lesões da 1ª biópsia e recorrentes de AMB. A sobrevida livre de recorrência foi analisada pelo método de Kaplan-Meier e as funções de sobrevida foram comparadas de acordo com as variáveis pelo teste log-rank. Resultados: O gênero mais acometido foi o feminino (n=24; 54,5%), com média de idade de acometimento de 39,1 ± 19,8 anos, sendo 45,5% (n=20) leucodermas. A região posterior de mandíbula foi a mais frequente no grupo recidivante (n=18, 81,8%) e também para os casos que não apresentaram recidivas (n=16, 72,8%). O tempo livre de recorrência foi de 50,0 (34,5 ­ 63,6) meses. Foram fatores significativamente associadas à recorrência dos ameloblastomas: presença de expansão da cortical (p=0,0089), ausência de reconstrução óssea (p=0,018), tratamento conservador (p=0,021), perda de imunoexpressão de hMSH2 (p=0,006) e hMLH1 (p=0,038) e forte imunoexpressão de Ki-67 (p=0,029). Conclusão: Baseado nos achados desta pesquisa, aspecto radiográfico, modalidade do tratamento e imunoexpressão de proteínas do Sistema Mismatch e Ki-67 podem ser utilizados como indicadores para a recorrência em ameloblastomas (AU).

Introduction: Ameloblastoma is a benign odontogenic neoplasm, which has high rates of postoperative recurrence. Several studies show the relationship between clinicopathological characteristics and treatment modalities in ameloblastoma recurrence. The molecular mechanisms involved in the etiopathogenesis of this tumor are little known, and although changes in the Mismatch System favor the development of different human neoplasms, their importance in the development of ameloblastoma still remains poorly understood. Objective: To identify clinical and pathological factors associated with ameloblastoma recurrence, as well as to investigate the role of immunoexpression of hMLH1, hMSH2 and Ki-67 proteins in the recurrence of these odontogenic tumors. Methodology: This was a descriptive, cross-sectional and retrospective study, with a sample consisting of 22 cases of recurrent ameloblastoma and 22 non-recurrent cases. Immunohistochemical analysis was performed quantitatively, considering the cellular (nuclear) location of the studied proteins. McNemar's test was used to compare variables between 1st biopsy and recurrent AMB lesions. Recurrence-free survival was analyzed using the Kaplan-Meier method and survival functions were compared according to variables using the log-rank test. Results: The most affected gender was female (n=24; 54.5%), with a mean age of involvement of 39.1 ± 19.8 years, 45.5% (n=20) being white. The posterior region of the mandible was the most frequent in the relapsed group (n=18, 81.8%) and also for the cases that did not present recurrences (n=16, 72.8%). Recurrence-free time was 50.0 (34.5 ­ 63.6) months. Factors significantly associated with recurrence of AMBs were: presence of cortical expansion (p=0.0089), absence of bone reconstruction (p=0.018), conservative treatment (p=0.021), loss of hMSH2 immunoexpression (p=0.006) and hMLH1 (p=0.038) and strong Ki-67 immunoexpression (p=0.029). Conclusion: Based on the findings of this research, radiographic appearance, treatment modality and immunoexpression of proteins from the Mismatch System and Ki-67 can be used as indicators for recurrence in ameloblastomas (AU).

Hemangioma capilar lobular: granuloma piógeno en lengua / Lobular capillary hemangioma: pyogenic granuloma of tongue

El granuloma piógeno es una lesión benigna, reactiva y multifactorial que resulta de le- siones repetitivas, microtraumatismos e irritación local en piel o mucosas y cambio hormonal. Cuando aparece en la cavidad oral tiene predilección por la encía vestibular, pero es importante que el odontólogo esté consciente y familiarizado con el hecho de que puede estar localizado en otras áreas anatómicas. Clínicamente se presenta como lesión hiperplásica altamente vascularizada, de tamaño generalmente no mayor a 2 cm, pediculada en la base o sésil y de lento crecimiento. Sin mostrar preferencia por edad o sexo, tiende a aparecer principalmente en encías, labios y mucosa oral, siendo muy pocos los casos reportados en el área lingual. Es por ello que, en este artículo, nos referimos a un caso de ubicación inusual, en conjunto con una revisión de la literatura (AU)

Pyogenic granuloma is a benign, reactive, and multifactorial lesion caused by repetitive injuries, microtrauma and local irritation on the skin or mucous membranes, and hormonal change. When it appears in the oral cavity, it has a predilection for the vestibular gingiva, but the dentist must be aware and familiar with the fact that it can be present in other anatomi- cal areas. Clinically, it is presented as a hyperplasic injury highly vascular-related, with a size generally no bigger than 2 cm, pedunculated in base or sessile, and slow in growth. Without showing any preference in age or gender, it tends to appear mainly on the gums, lips, and oral mucosae, with very few, reported cases in the lingual area. Therefore, in this study, we refer to a case of unusual localization with a literature review (AU)

Carcinoma del conducto salival: estudio clínico/patológico e inmunohistoquímico de 5 casos / Salivary duct carcinoma: a clinicopathologic and inmunohistochemical study of 5 cases

El carcinoma del conducto salival es un tumor epitelial maligno agresivo, que involucra principalmente a la glándula parótida, con características histológicas semejantes al carcinoma ductal de glándula mamaria. El propósito de este trabajo fue presentar los resultados clínico-patológicos de cinco casos de carcinoma del conducto salival primario de glándula parótida y evaluar la expresión de Ki67. Histológicamente, el carcinoma del conducto salival presentó nidos epiteliales con patrones papilar, sólido y cribiforme, comedonecrosis tanto en la lesión primaria como en los nodos linfoides metastásicos y, además, invasión perineural. Se demostró con Ki 67 una alta proliferación celular en cuatro (80 %) de los cinco casos estudiados. Se concluyó que: el carcinoma del conducto salival es una lesión maligna de mal pronóstico, raramente informado en la literatura odontológica, con características histológicas semejantes a las del carcinoma ductal de alto grado de la mama; la comedonecrosis es un signo específico de esta enfermedad; puede desarrollarse "de novo" o en un adenoma pleomórfico preexistente; su diagnóstico diferencial histopatológico es fundamental para planificar su tratamiento y determinar su pronóstico, a pesar de su tratamiento quirúrgico y radioterapia postoperatoria es un tumor agresivo con alta proliferación celular, infiltración perineural, recurrencias y metástasis.

Salivary duct carcinoma is an aggressive malignant epithelial tumor, primarily involving the parotid gland, with histologic features similar to ductal carcinoma of the breast. The purpose of this work was to report the clinicopathological results of five cases of primary salivary duct carcinoma of the parotid gland and evaluate the expression of Ki67. Histologically, salivary duct carcinoma presented epithelial nests with papillary, solid, and cribriform patterns, with comedonecrosis in both the primary lesion and the metastatic limph nodes, and perineural invasion. A high cell proliferation was demonstrated with Ki67 in four (80 %) of the five cases studied. We concluded that: salivary duct carcinoma is a malignant lesion with a poor prognosis, rarely reported in the dental literature, with histological characteristics similar to those of high-grade ductal carcinoma of the breast; comedonecrosis is a specific sign of this disease; may develop "de novo" or in a pre-existing pleomorphic adenoma; its differential histopathological diagnosis is essential to plan its treatment and determine its prognosis; despite its surgical treatment and postoperative radiotherapy, it is an aggressive tumor with high cell proliferation, perineural infiltration, recurrences and metastasis.

Métodos histoquímicos e inmunohistoquímicos para la estimación del Intervalo postmortem en tejidos humanos: una revisión / Histochemical and immunohistochemical methods for the postmortem interval estimation in human tissues: a review

El intervalo postmortem (IPM) es un importante desafío a resolver en patología forense, y consiste en poder determinar el tiempo transcurrido desde la muerte hasta el momento de la autopsia. Dada la poca confiablidad de algunos métodos por la gran influencia de factores externos, la Histoquímica (HQ) y la Inmunohistoquímica (IHQ), entre otros, han recibido considerable atención por sus niveles de objetividad en la investigación forense. Se presenta una revisión con búsqueda sistemática de estudios experimentales que apliquen métodos HQs e IHQs para la estimación del IPM sobre material cadavérico humano. Se identificaron 1053 artículos de los cuales 12 cumplieron con los criterios, a los que se agregaron 4 mediante una búsqueda manual (n=16 artículos). Alemania fue el país con más publicaciones destacando con 8 artículos. Las técnicas HQs de AgNORs, TRAP y PAS fueron utilizadas en 5 estudios (glándulas sudoríparas, piel, hígado, médula ósea y mucosa labial), mientras que las IHQs fueron empleadas con diferentes grupos antigénicos en 12 estudios (páncreas, cerebro, pulmón, tiroides, hígado, glándulas pituitarias, glándulas sudoríparas y mucosa gingival). Las estimaciones del IPM fueron posibles con márgenes entre 2-3 h. hasta los 20 días dependiendo de la técnica. El análisis de tejidos provenientes de cavidad oral asegura una vía no invasiva, de fácil acceso y bajo resguardo natural a la influencia de factores ambientales. Si bien no existe un método único que permita de manera confiable estas estimaciones, la introducción de nuevas técnicas permitiría evitar la producción de errores.

The postmortem interval (IPM) is an important challenge to be solved in forensic pathology, and it consists in determine the time elapsed since death until the autopsy. Given the low reliability of some methods due to the great influence of external factors, Histochemistry (HQ) and Immunohistochemistry (IHQ), among others, have received considerable attention for their levels of objectivity in forensic investigation. A scoping review of experimental studies that apply HQs and IHQs methods to estimate the MPI on human cadaveric material is presented. We identified 1053 articles, of which 12 met the criteria; we added 4 articles through a manual search (n = 16 articles). Germany was the most productive country, with 8 articles. HQ techniques of AgNORs, TRAP and PAS were used in 5 studies (on sweat glands, skin, liver, bone marrow and labial mucosa), while IHQs techniques were used with different antigenic groups in 12 studies (on pancreas, brain, lung, thyroid, liver, pituitary glands, sweat glands and gingival mucosa). IPM estimates were possible with margins between 2-3 hours up to 20 days depending on the technique. The analysis of oral tissues ensures a non-invasive route, easily accessible and under natural protection to the influence of environmental factors. Although there is no single method that reliably allows these estimates, the introduction of new techniques would prevent the production of errors.

Estudo da correlação das proteínas INGs com a P53 em lesões odontogênicas epiteliais benignas / Study of the correlation of INGs proteins with P53 in benign epithelial odontogenic lesions

As proteínas INGs (inhibitor of growth gene) desempenham papel de supressoras tumorais e podem agir por vias dependentes, ou independentes, da p53 na sinalização do ciclo celular e da apoptose. Este trabalho investigou, por meio de imuno-histoquímica, a correlação entre a expressão das proteínas INGs e a expressão da proteína p53 em ceratocistos odontogênicos (20), TOAs (20) e ameloblastomas sólidos (20). Os espécimes foram submetidos à marcação utilizando os anticorpos anti-Ing3, anti-Ing4, anti-Ing5 e anti-p53. Foi realizada análise quantitativa levando-se em consideração a localização citoplasmática e/ou nuclear para as proteínas INGs e a localização nuclear para a proteína p53. A análise da imunoexpressão das proteínas ING1 e ING2 foi realizada em um estudo prévio e os resultados foram considerados apenas para a análise de correlação com as proteínas estudadas neste estudo. Os dados foram analisados pelo Statistical Package for Social Sciences para Windows (SPSS versão 22.0; IBM, USA). Para a comparação da imunoexpressão entre os grupos de lesões foi utilizado o teste de Kruskal Wallis, e para a investigação das correlações foi utilizado o teste de Spearman. Foram considerados significativos os valores de p ≤ 0.05. O presente estudo evidenciou redução da expressão nuclear e citoplasmática das proteínas ING3, ING4 e ING5 em ceratocistos odontogênicos (COs) e ameloblastomas (AMBs). Além disso, em alguns casos, a perda da expressão nuclear das INGs esteve negativamente correlacionada à expressão da proteína p53. As análises de correlação entre as proteínas INGs indicam a existência de mecanismos compensatórios entre as proteínas INGs em folículos dentários (FDs) e tumores odontogênicos adenomatoides (TOAs), estes mecanismos parecem ser menos evidentes em COs e AMBs. Observou-se redução na expressão da proteína ING3 em AMBs (p=0,003); redução na expressão da proteína ING4, tanto em AMBs (p=0,02) quanto em COs (p=0,001); e uma redução da expressão nuclear da proteína ING5 nos COs (p=0,09) e nos AMBs (p=0,012). Foram evidenciadas correlações positivas entre a expressão nuclear da p53 com a expressão citoplasma/núcleo da proteína ING1 (r=0,603; p=0,05) em COs, e com a expressão citoplasma/ núcleo das proteínas ING3 (r=0,475; p=0,034) e ING4 (r=0,448; p=0,047) em AMBs. Por fim, os resultados deste estudo sugerem que a redução na expressão nuclear das proteínas INGs pode ser um evento envolvido na etiopatogênese de lesões odontogênicas mais agressivas, e que a redução da expressão nuclear/citoplasmática das proteínas INGs não está relacionada ao aumento expressão da p53 em COs e AMBs, o que sugere que a expressão destas proteínas deve resultar em alterações funcionais de maneira independente da p53 em lesões odontogênicas (AU).

INGs (inhibitor of growth gene) proteins play a role of tumor suppressors and can act via p53-dependent or independent pathways in signaling cell cycle and apoptosis. The aim of this study is to evaluate correlation between expression of proteins of ING proteins and expression of protein p53 in dental follicles (DF), odontogenic keratocysts (OK), adenomatoid odontogenic tumors (AOT) and solid ameloblastomas (AMBs). The sample was intentional and non-probabilistic, consisting of 20 cases of solid AMBs, 20 cases of AOT, 20 cases of OKs and 10 samples of DFs. The specimens were subjected to immunohistochemical method, using antibodies anti-Ing3, anti-Ing4, anti-Ing5 and antip53. Quantitative analysis was performed taking into account cytoplasmic and / or nuclear location for ING proteins and nuclear location for the p53 protein. The analysis of ING1 and ING2 immunoexpressions was performed in a previous study and the results were considered only for the correlation analysis. Data were analyzed by Statistical Package for Social Sciences for Windows (SPSS version 22.0; IBM, USA). Kruskal Wallis test was used to compare the immunoexpression between the groups of lesions, and Spearman test was used to investigate correlations. Values of p ≤ 0.05 were considered significant. This study showed a reduction in nuclear and cytoplasmic expression of ING3, ING4 and ING5 in odontogenic keratocysts (OKs) and ameloblastomas (AMBs). In addition, in some cases, loss of INGs nuclear expression was negatively correlated with p53 expression. Correlation analyzes may indicate existence of compensatory mechanisms between all the ING proteins in dental follicles (FDs) and adenomatoid odontogenic tumors (TOAs). These mechanisms seem to be less evident in COs and AMBs. The results of this study showed a reduction in ING3 expression in AMBs (p = 0.003); a reduction in ING4 expression, in OKs (p = 0.02) and in AMBs (p = 0.001); and a reduction in ING5 nuclear expression, also in OK (p = 0.09) and in AMBs (p = 0.012). Positive correlations were found between p53 nuclear expression with ING1 cytoplasm / nucleus expression (r = 0.603; p = 0.05) in OKs, and with ING3 cytoplasm / nucleus expression (r = 0.475; p = 0.034) and also ING4 cytoplasm / nucleus expression (r = 0.448; p = 0.047) in AMBs. Finally, this study suggests that reduction in the expression of INGs proteins seems to be an event that occurred in etiopathogenesis of more aggressive odontogenic lesions. Futhermore, nuclear / cytoplasmic expression of INGs proteins is not related to increase in p53 expression in OKs and AMBs, which indicates that loss of expression of these proteins may results in functional changes independently of p53 (AU).

Estudo imuno-histoquímico e in vitro de proteínas do sistema ativador de plasminogênio em carcinomas de células escamosas de língua oral / Immunohistochemical and in vitro study of plasminogen activator system proteins in oral tongue squamous cell carcinomas

O carcinoma de células escamosas (CCE) é a neoplasia maligna mais frequente da cavidade oral e apresenta prognóstico desfavorável. Assim sendo, pesquisas têm buscado esclarecer o papel de biomarcadores no comportamento biológico do CCE oral. Nesta perspectiva, destacam-se o ativador de plasminogênio tipo uroquinase (uPA) e seu receptor (uPAR), além do inibidor do ativador de plasminogênio-1 (PAI-1). O presente trabalho analisou, por meio de imuno-histoquímica, a expressão das proteínas uPA, uPAR e PAI-1 no CCE de língua oral (CCELO) e sua relação com parâmetros clinicopatológicos. Este experimento também avaliou os efeitos in vitro da proteína recombinante humana PAI-1 (rhPAI-1) na linhagem celular SCC25, derivada de CCELO. A imunoexpressão de uPA, uPAR e PAI-1 foi analisada em 60 casos de CCELO, de forma semiquantitativa, nas células neoplásicas do front de invasão tumoral. Visando a associação dos achados imuno-histoquímicos com variáveis clinicopatológicas e taxas de sobrevida, os casos foram classificados nas categorias baixa expressão (≤50% das células positivas) e alta expressão (>50% das células positivas). No experimento in vitro, foram analisados os seguintes grupos: G0 (controle; células cultivadas na ausência de rhPAI-1), G10 (células tratadas com rhPAI-1 a 10 nM) e G20 (células tratadas com rhPAI-1 a 20 nM). Diferenças entre estes grupos foram investigadas através dos ensaios: viabilidade celular (Alamar Blue), ciclo celular (marcação com iodeto de propídio, PI), apoptose/necrose (marcação com Anexina V e PI), atividade migratória (Wound healing) e invasão celular (Transwell). A análise imuno-histoquímica revelou alta expressão do uPA na maioria dos CCELOs, mas sem relações significativas com parâmetros clinicopatológicos. As expressões do uPAR e do PAI-1, em nível membranar, foram associadas a recidivas locais (p=0,019) e ao elevado tumor budding (p=0,046), respectivamente. A expressão membranar do PAI-1 também apresentou associação significativa com o alto escore de risco histopatológico (p=0,043). A análise estatística evidenciou ausência de associações significativas entre as variáveis imunohistoquímicas (uPA, uPAR e PAI-1) e indicadores de prognóstico do CCELO (sobrevida específica e sobrevida livre da doença). No estudo in vitro, decorridas 24 horas da administração da rhPAI-1, os grupos G10 e G20 exibiram maior viabilidade celular em comparação ao grupo controle (p=0,020), assim como aumento da progressão para a fase S do ciclo celular (p=0,024). No que concerne aos percentuais de células apoptóticas e necróticas, não foram encontradas diferenças significativas entre os grupos. Nos grupos celulares cultivados na presença da rhPAI1, também foi constatado aumento da atividade migratória (p=0,039) e do potencial de invasão (p=0,039), respectivamente, nos intervalos de 24 horas e 72 horas. Os achados deste estudo sugerem o envolvimento das proteínas uPA, uPAR e PAI-1 na patogênese do CCELO. Entretanto, a expressão destes biomarcadores pode não estar relacionada com a sobrevida dos pacientes. Os resultados in vitro demonstram que o PAI-1 exerce efeitos estimulatórios na proliferação, migração e invasão celular, podendo assim contribuir para a agressividade biológica do CCELO (AU).

Squamous cell carcinoma (SCC) is the most frequent malignant neoplasm of the oral cavity and has an unfavorable prognosis. Thus, studies have sought to clarify the role of biomarkers in the biological behavior of oral SCC. Within this context, urokinase-type plasminogen activator (uPA) and its receptor (uPAR), as well as plasminogen activator inhibitor 1 (PAI-1), are particularly interesting. The present study analyzed, by means of immunohistochemistry, the expressions of uPA, uPAR and PAI-1 in oral tongue SCC (OTSCC) and their relationship with clinicopathological parameters. This experiment also evaluated the in vitro effects of recombinant human PAI-1 (rhPAI-1) on the OTSCC-derived cell line SCC-25. The immunoexpression of uPA, uPAR and PAI-1 was analyzed semiquantitatively in neoplastic cells of the invasion front of 60 OTSCC cases. Aiming to determine the association between immunohistochemical findings, clinicopathological variables and survival rates, the cases were classified as low expression (≤50% of positive cells) and high expression (>50% of positive cells). The following groups were analyzed in the in vitro experiment: G0 (control; cells cultured in the absence of rhPAI-1), G10 (cells treated with 10 nM rhPAI-1), and G20 (cells treated with 20 nM rhPAI-1). Differences between these groups were investigated using the following assays: cell viability (Alamar Blue), cell cycle (staining with propidium iodide, PI), apoptosis/necrosis (staining with Annexin V and PI), migratory activity (Wound healing), and cell invasion (Transwell). Immunohistochemical analysis revealed high expression of uPA in most OTSCC cases, but there were no significant associations with clinicopathological parameters. The high membrane expression of uPAR and PAI-1 was associated with local recurrence (p=0.019) and high tumor budding (p=0.046), respectively. Membrane expression of PAI-1 also presented a significant association with high-risk cases (p=0,043). Statistical analysis demonstrated no significant associations between the immunohistochemical variables (uPA, uPAR and PAI-1) and prognostic indicators of OTSCC (disease-specific and disease-free survival). In the in vitro experiment, 24 hours after administration of rhPAI-1, G10 and G20 exhibited greater cell viability compared to the control group (p=0.02), as well as increased progression to the S phase of the cell cycle (p=0.024). There were no significant differences in the percentages of apoptotic or necrotic cells between groups. In the groups cultured in the presence of rhPAI-1, migratory activity (p=0.039) and invasion potential (p=0.039) were found to be increased after 24 and 72 hours, respectively. The findings of this study suggest the involvement of uPA, uPAR and PAI-1 in the pathogenesis of OTSCC. Nevertheless, the expression of these biomarkers may not be related to survival of patients. The in vitro results suggest that PAI-1 exerts stimulatory effects on cell proliferation, migration and invasion and may therefore contribute to the biological aggressiveness of OTSCC (AU).

Melanoma cutáneo asociado a la mutación del gen BRAF en dos hospitales de la ciudad de Guatemala / Cutaneous melanoma associated with the mutation of the BRAF gene in two hospitals from Guatemala City

Los estudios de melanoma en Guatemala han sido pocos y únicamente se ha evaluado el aspecto clínico e histológico. El objetivo del presente estudio fue determinar la proporción de casos de melanoma cutáneo por morfología, inmunohistoquímica y mutación del gen BRAF en pacientes con diagnóstico de melanoma en dos centros de referencia, Instituto de Cancerología e Instituto de Dermatología en Guatemala. El estudio es de tipo descriptivo, retrospectivo, transversal. El tipo de muestreo es no probabilístico, con una muestra por conveniencia de 100 casos de tejidos de piel de pacientes, caracterizados por edad, sexo y localización del tumor. Los estudios moleculares incluyeron la determinación de la mutación de la proteína BRAF, por la técnica de PCR-RT. Los resultados muestran que el sexo más afectado es el femenino (54 %). El grupo etario con mayor número de casos es entre 56-75 años (44 %). El tipo histológico predominante es el melanoma lentiginoso acral (59 %) y la localización más frecuente es en miembro inferior (71 %). No se encontraron casos de melanoma lentigo maligno. La mutación del gen BRAF se encontró en el 6 % de los casos, lo que representa un dato importante para el pronóstico y tratamiento del paciente. Por ser uno de los primeros estudios que incluyen el factor molecular, abre paso a una línea de investigación que permita dar continuidad a los pacientes con melanoma en Guatemala, lo que permitirá determinar factores pronóstico y predictivos, así como tratamientos de los casos en estudio.

Studies of melanoma in Guatemala have been few and only the clinical and histological aspects have been evaluated. The objective of this study was to determine the proportion of cases of cutaneous melanoma by morphology, immunohistochemistry and mutation of the BRAF gene in patients diagnosed with Melanoma in two important reference centers, Institute of Cancerology (Incan) and Institute of Dermatology of Guatemala (Inderma). The study is descriptive, retrospective, transversal. The type of sampling is non-probabilistic, with a convenience sample calculation of 100 cases of patient skin biopsies, characterized by age, sex and tumor anatomic location. Molecular studies included the determination of the BRAF protein mutation by means of the RT-PCR technique. Results show that the most affected sex is the female (54 %). Age group with the highest number of cases is between 56 and 75 years old (44 % of cases). The histological type that predominated is acral lentiginous melanoma (59 %) and the most frequent location is in the lower limb (71 %). No cases of malignant lentigo melanoma were found in the cases studied. The BRAF gene mutation was found in 6 % of the cases, which represents an important data for the prognosis and treatment of the patient. In addition, being one of the first studies that include the molecular factor, it opens the way to a line of research that allows patients with melanoma to continue in Guatemala. This would allow to determine prognostic and predictive factors, as well as treatments of the cases under study.

Analysis of Estrogen Effects on Eruption of Rat Molars / Análisis de los Efectos del Estrógeno en la Erupción de Molares de Rata

ABSTRACT: Tooth eruption requires resorption of the alveolar bone interposed between the tooth germ and the oral mucosa (coronal bone). The cells responsible for bone resorption are the osteoclasts and their activity can be reduced or inactivated by estrogen hormone. We aimed to investigate the effects of estrogen on the process of tooth eruption in rats. Thirty-three Wistar rats, aged two-to-17-days, were divided into control, sham and estrogen-treated groups. After daily injections with estrogen, the animals were euthanized and the jaws removed and processed for histological analysis. We performed clinical examination, morphological analysis, quantification of the number of osteoclasts on the surface of the coronal bone and immunohistochemical analysis of estrogen receptor type alpha (ERα). Estrogen therapy was effective, which could be confirmed by the higher estrogen plasma levels on treated animals. However, it had no effect on tooth development or tooth eruption. Progressive bone resorption was observed and the number of osteoclasts on coronal bone was not affected on hormoneinjected animals, allowing tooth to erupt at the same time observed in untreated animals. Immunohistochemistry for ERα confirmed the presence of this type of receptor in osteoclasts, osteoblasts and osteocytes. Taken together, our results showed that estrogen stimulation was not sufficient to decrease the number of osteoclasts on the coronal bone, supporting the idea that, although estrogen may have a protective activity on bone resorption, this may not apply to the alveolar bone that is meant to be resorbed during eruptive process.

RESUMEN: La erupción dental requiere la resorción del hueso alveolar interpuesto entre el germen dental y la mucosa oral (hueso coronal). Las células responsables de la resorción ósea son los osteoclastos y su actividad puede reducirse o inactivarse por la hormona del estrógeno. Objetivos: apuntamos a investigar los efectos del estrógeno en el proceso de la erupción dental en ratas. Treinta y tres ratas Wistar, de dos a 17 días de edad, se dividieron en grupos de control, Sham y se trataron con estrógenos. Los animales fueron eutanizados después del tratamento con estrógeno y se procesaron las mandíbulas para el análisis histológico. Se realizó el examen clínico, el análisis morfológico, la cuantificación del número de osteoclastos en la superficie del hueso coronal y el análisis inmunohistoquímico del tipo de receptor de estrógeno alfa (ERα). La terapia de estrógeno fue eficaz, lo que podría ser confirmado por los niveles plasmáticos más altos de estrógeno en los animales tratados. Sin embargo, no se observó ningún efecto sobre el desarrollo de los dientes o la erupción dental. Se observó una resorción ósea progresiva y el número de osteoclastos en el hueso coronal no se vio afectado en los animales inyectados con hormonas, permitiendo que el diente erupcionó durante el mismo período de tiempo observado en animales no tratados. La inmunohistoquímica para el ERα confirmó la presencia de este tipo de receptor en los osteoclastos, osteoblastos y osteocitos. Nuestros resultados mostraron que la estimulación del estrógeno no fue suficiente para reducir el número de osteoclastos en el hueso coronal confirmando que, si bien el estrógeno puede tener una actividad protectora en la resorción ósea, esto puede no se aplica al hueso alveolar que está destinado a ser rerecurrido durante el proceso eruptivo.

Sarcoma neurogénico de la mama masculina. Presentación de un caso / Male breast neurogenic sarcoma. A case

RESUMEN El cáncer de mama en el sexo masculino es una entidad clínica poco frecuente, tiene una presentación unimodal a los 71 años de edad, generalmente se presenta de manera similar a la forma en que se presenta en el sexo femenino. Su causa es poco conocida. Los sarcomas son tumores de componentes mesenquimatoso que constituyen del 0,2-1 % de todos los tumores de mama, y menos del 5 % del total. El sarcoma neurogénico, a su vez, es un tumor extremadamente raro. Representa del 1-2 % aproximadamente, de los tumores de los nervios periféricos con transformación maligna. Debido a la rareza geográfica e histopatológica de este tipo y mucho más en pacientes masculinos se presentó este caso. Paciente masculino de 57 años de edad, con el diagnóstico de un sarcoma de la mama derecha. Se le realizó una mastectomía radical más quimioterapia y radioterapia adyuvante. Los estudios de inmunohistoquímicos permitieron llegar al diagnóstico de sarcoma neurogénico.

ABSTRACT Breast cancer in men (BCM) is a rare clinical entity that has a unimodal presentation at the age of 71 years, and generally presents in a similar way it presents in the female sex. Its etiology remains almost unknown. Sarcomas are tumors of mesenchymal components representing from 0.2 to 1 % of all the breast tumors and less than 5 % of the total. The neurogenic sarcoma is also an extremely rare tumor. It represents around 1-2 % of the peripheral nerves tumors with malignant transformations. Due to location and histopathological rarity of this kind of tumors, much more in male patients, the authors presented the case of a male patient, aged 57 years, with the diagnosis of a left breast sarcoma. He undergone a radical mastectomy plus adjuvant chemotherapy and radiotherapy. The immunohystochemical studies allowed arriving to the diagnosis of neurogenic sarcoma.

Análise da imunoexpressão de proteínas de reparo do DNA envolvidas nas vias BER e NER em lesões odontogênicas epiteliais benignas / Immunoexpression analysis of DNA repair proteins involved in BER and NER pathways in benign epithelial odontogenic lesions

As lesões odontogênicas epiteliais benignas apresentam comportamento biológico heterogêneo e patogênese ainda não totalmente esclarecida. As vias de reparo do ácido desoxirribonucleico (DNA) atuam em tipos específicos de danos ao material genético, realizando o reparo e regulando diversos processos celulares. Dentre as principais vias de reparo do DNA, destacamse o reparo por excisão de bases (BER) e o reparo por excisão de nucleotídeos (NER). Investigações têm demonstrado que as proteínas envolvidas nessas vias se encontram desreguladas e, por vezes, altamente expressas em algumas neoplasias malignas, contribuindo para a progressão tumoral. Levando em consideração a heterogeneidade do comportamento biológico das lesões odontogênicas epiteliais benignas e a escassez de estudos que tenham avaliado a expressão de proteínas de reparo do DNA nestas lesões, este trabalho avaliou a imunoexpressão de proteínas da via BER (APE-1 e XRCC-1) e NER (XPF) em ameloblastomas (AMEs) sólidos (n = 30), ceratocistos odontogênicos não sindrômicos (CONS) (n = 30), ceratocistos odontogênicos sindrômicos (COS) (associados à Síndrome de Gorlin) (n = 29), cistos dentígeros (CDs) (n = 30) e folículos dentários (FDs) (n = 20). A análise da expressão imunoistoquímica de APE-1, XRCC-1 e XPF foi realizada de forma quantitativa por um avaliador previamente calibrado e sem acesso aos dados clínicos dos casos. Em cinco campos de maior imunorreatividade, foram quantificadas as células positivas e negativas para as proteínas no componente epitelial de todos os casos, sendo estabelecido o percentual de células positivas em relação ao número total de células contadas para cada anticorpo. As marcações nucleares e citoplasmáticas foram analisadas separadamente para APE-1 e XPF, enquanto apenas a imunoexpressão nuclear foi considerada para XRCC-1. As comparações das medianas dos percentuais de imunorreatividade em relação aos grupos estudados foram realizadas por meio dos testes não paramétricos de Kruskal-Wallis e Mann-Whitney. Possíveis correlações entre a expressão de APE-1, XRCC-1 e XPF foram avaliadas por meio do teste de correlação de Spearman. O nível de significância foi estabelecido em 5% (p < 0,05). Foi verificada uma maior imunoexpressão nuclear de APE-1 nos CONSs, COSs e AMEs sólidos, em comparação com os CDs (p < 0,001). Dentre todos os grupos avaliados, a expressão citoplasmática de APE1 só foi encontrada em 4 CONSs e 6 COSs. A expressão nuclear de XRCC-1 foi estatisticamente maior nos CONSs e COSs em relação aos CDs (p < 0,05). Em nível nuclear, a expressão de XPF foi significativamente maior nos CONSs e COSs em relação aos CDs e AMEs (p < 0,05) e, embora sem significância estatística, foi observada uma maior expressão nuclear dessa proteína nos AMEs quando comparado aos CDs. Em relação à expressão citoplasmática de XPF, foi observada uma maior expressão nos COSs em relação aos CDs (p = 0,04). Nenhuma diferença estatisticamente significativa foi encontrada entre as expressões nucleares de APE-1, XRCC-1 e XPF entre CONSs e COSs (p > 0,05). Além disso, todas as lesões odontogênicas estudadas revelaram uma maior expressão estatisticamente significativa de APE-1 (nuclear), XRCC-1 (nuclear) e XPF (nuclear e citoplasmática) quando comparados aos FDs (p < 0,05). Para todas as lesões, o teste de correlação de Spearman mostrou uma correlação positiva entre a expressão nuclear de APE-1 e XRCC-1 ou XPF, em nível nuclear (p < 0,05). Os resultados deste estudo sugerem um potencial envolvimento das proteínas APE-1, XRCC-1 e XPF na patogênese das lesões odontogênicas epiteliais benignas, com destaque para aquelas com comportamento biológico mais agressivo (AU).

The benign epithelial odontogenic lesions present a heterogeneous biological behavior and their pathogenesis are not fully understood. The deoxyribonucleic acid (DNA) repair pathways act on specific types of damage to the genetic material, performing the repair and regulating several cellular processes. Among the main DNA repair pathways, the most notable are the base excision repair (BER) and the nucleotide excision repair (NER). Investigations have shown that the proteins involved in these pathways are deregulated and sometimes highly expressed in some malignancies, contributing to tumor progression. Taking into account the heterogeneity of the biological behavior of benign epithelial odontogenic lesions and the scarcity of studies that have evaluated the expression of DNA repair proteins in these lesions, this study evaluated the immunoexpression of BER (APE-1 and XRCC-1) proteins and NER (XPF) in solid ameloblastomas (AMEs) (n = 30), non-syndromic odontogenic keratocysts (NSOKCs) (n = 30), syndromic odontogenic keratocysts (SKOCs) (associated with Gorlin's Syndrome) (n = 29), dentigerous cysts (DCs) (n = 30) and dental follicles (DFs) (n = 20). The immunohistochemical analysis of APE-1, XRCC-1 and XPF was performed quantitatively by a previously calibrated evaluator and without access to the clinical data of the cases. In five fields of higher immunoreactivity, positive and negative cells were quantified for the proteins in the epithelial component of all cases, and the percentage of positive cells was established in relation to the total number of cells counted for each antibody. Nuclear and cytoplasmic markers were analyzed separately for APE-1 and XPF, while only nuclear immunoexpression was considered for XRCC-1. The comparisons of the median percentages of immunoreactivity in relation to the studied groups were performed using the non-parametric Kruskal-Wallis and MannWhitney tests. Possible correlations between the expression of APE-1, XRCC-1 and XPF were assessed by Spearman's correlation test. The level of significance was set at 5% (p < 0.05). A higher nuclear immunoexpression of APE-1 in the NSOKCs, SOKCs and solid AMEs was verified in comparison with the DCs (p < 0.001). Among all the evaluated groups, the cytoplasmic expression of APE-1 was only found in 4 NSOKCs and 6 SOKCs. Nuclear expression of XRCC-1 was statistically higher in NSOKCs and SOKCs than in DCs (p < 0.05). At the nuclear level, XPF expression was significantly higher in NSOKCs and SOKCs than in DCs and AMEs (p < 0.05) and, although without statistical significance, a higher nuclear expression of this protein was observed in AMEs when compared to CDs. Regarding the cytoplasmic expression of XPF, a greater expression was observed in the SOKCs in relation to the DCs (p = 0.04). No statistically significant difference was found between the nuclear expressions of APE-1, XRCC-1 and XPF between NSOKCs and SOKCs (p > 0.05). In addition, all the odontogenic lesions studied revealed a statistically significant expression of APE-1 (nuclear), XRCC-1 (nuclear) and XPF (nuclear and cytoplasmic) when compared to DFs (p < 0.05). For all lesions, Spearman's correlation test showed a positive correlation between nuclear expression of APE-1 and XRCC-1 or XPF at the nuclear level (p < 0.05). The results of this study suggest a potential involvement of APE-1, XRCC-1 and XPF proteins in the pathogenesis of benign epithelial odontogenic lesions. The role played by these proteins may be more important in odontogenic lesions with more aggressive biological behavior (AU).

Low p27kip1 expression in head and neck squamous cell carcinoma: association with risk factors and adverse outcomes

Background: Squamous cell carcinoma (SCC) of head and neck is highly prevalent in South-asian countries, owing to high consumption of areca nut/gutka and chewing tobacco. p27kip1 is a tumor suppressor gene, thought to be downregulated in oral squamous cell carcinoma. Therefore, in the present study we used immunohistochemical analysis to investigate an association between low p27kip1 expression in SCC of the head and neck and adverse outcomes/risk factors. Methods: Total 105 cases of SCC of head and neck excision specimens were selected from records of pathology department archives that underwent surgeries at Liaquat National hospital, Karachi from January 2008 till December 2013. Clinical and pathologic characteristics of patients were evaluated and p27kip1 immunohistochemistry was applied on tumor blocks. Results: In our study, low expression of p27kip1 in SCC of head and neck was seen in 39(37.1%) cases while 66(62. 9%) of the cases showed high expression for p27kip1. Significant association of p27kip1 expression with pan/gutka usage (p = 0.004), and recurrence (p = 0.001) was noted; however, no significant association of p27kip1 expression with other clinicopathologic features was seen. Multivariate binary logistic regression showed cases with history of pan/gutka usage were more likely to show low p27kip1 expression. Similarly, we also found that recurrence was more likely to develop in patients with low expression of p27kip1 in comparison to cases showing high p27kip1 expression. Conclusion: Loss of p27kip1 expression is a significant event involved in the pathogenesis of SCC head and neck especially that of oral cavity. Significant association of gutka/areca nut with low p27kip1 expression in our study suggests that loss p27kip1 expression is a major event involved in areca nut induced SCC of head and neck in this part of the world; however, more large scale molecular based studies are required to validate this observation. Moreover, significant association of low p27kip1 expression with tumor recurrence suggests its importance as a prognostic biomarker in SCC of head and neck (AU)

The Mechanistic Basis for Photobiomodulation Therapy of Neuropathic Pain by Near Infrared Laser Light

Background and Objective Various irradiances have been reported to be beneficial for the treatment of neuropathic pain with near infrared light. However, the mechanistic basis for the beneficial outcomes may vary based on the level of irradiance or fluence rate used. Using in vivo and in vitro experimentalmodels, this study determined the mechanistic basis of photobiomodulation therapy (PBMT) for the treatment of neuropathic pain using a high irradiance. Study Design/Materials and Methods ln vitro experiments: Cultured, rat DRG were randomly assigned to control or laser treatment (L T) groups with different irradiation times (2, 5, 30, 60 or 120s). The laser parameters were: output power » 960 mW, irradiance » 300mW/cm2, 808 nm wavelength and spot size » 3cm diameter/ area » 7.07cm2, with different fluences according to irradiation times. Mitochondrial metabolic activity was measured with the MTS assay. The DRG neurons were immunostained using a primary antibody to ß-Tubulin III. ln vivo experiments: spared nerve injury surgery (SNI), an animal model of persistent peripheral neuropathic pain, was used. The injured rats were randomly divided into three groups (n » 5). 1) Control: SNI without LT, 2) Short term: SNI with LT on day 7 and euthanized on day 7, 3) Long term: SNI with LT on day 7 and euthanized on day 22. An 808 nm wavelength laser was used for all treatment groups. Treatment was performed once on Day 7 post-surgery. The transcutaneous treatment parameters were: output power: 10 W, fluence rate: 270 mW/cm2, treatment time: 120s. The laser probe was moved along the course of the sciatic/sural nerve during the treatment. Within 1 hour of irradiation, behavior tests were performed to assess its immediate effect on sensory allodynia and hyperalgesia caused by SNI. Results ln vitro experiments: Mitochondrial metabolism was significantly lower compared with controls for all LT groups. Varicosities and undulations formed in neurites of DRG neurons with a cell body diameter 30µm or less. ln neurites of DRG neurons with a cell body diameter of greater than 30µm, varicosities formed only in the 120s group. ln vivo experiments: For heat hyperalgesia, there was a statistically significant reduction in sensitivity to the heat stimulus compared with the measurements done on day 7 prior to LT. A decrease in the sensitivity to the heat stimulus was found in the LT groups compared with the control group on day 15 and 21. For cold allodynia and mechanical hyperalgesia, a significant decrease in sensitivity to cold and pin prick was found within 1 hour after L T. Sensitivity to these stimuli returned to the control levels after 5 days post-L T. No significant difference was found in mechanical allodynia between control and L T groups for all time points examined. Conclusion These in vitro and in vivo studies indicate that treatment with an irradiance/fluence rate at 270 m W/cm2 or higher at the level of the nerve can rapidly block pain transmission. A combination therapy is proposed to treat neuropathic pain with initial high irradiance/fluence rates for fast pain relief, followed by low irradiance/ fluence rates for prolonged pain relief by altering chronic inflammation.

Leiomiosarcoma rectal: reporte de un caso / Rectal leiomyosarcoma: a case report

Introducción: Los leiomiosarcomas (LMS) son tumores raros del tubo digestivo, corresponden a neoplasias malignas originadas de células de músculo liso, representando sólo el 0,1% del total. La localización rectal se da en el 11% de los LMS, aunque representan menos del 1% de los tumores malignos colón- icos. En nuestro medio también es una patología de baja frecuencia. Objetivo: Exponer método diagnóstico, tratamiento, y resultado quirúrgico en paciente con LMS rectal. Caso Clínico: Paciente mujer, 53 años, atendida en el Hospital Padre Hurtado, gran tabáquica, que se presentó con un cuadro de 1 año de evolución de dolor perianal, defecación laboriosa y 3 episodios de rectorragia. Al examen físico presentaba al tacto rectal a 4 cm del margen anal una masa de ±2 cm de superficie irregular y de consistencia pétrea. Se realizó colonoscopía objetivando la masa tumoral y tomando biopsia la que se informó como LMS rectal, incluyendo resultados de inmunohistoquímica. Siguiendo con el estudio se realizó TAC y RNM. Se decide la intervención quirúrgica realizándose una resección anterior baja, sin incidentes durante la cirugía y con un buen postoperatorio. Conclusión: El leiomiosarcoma es de extrema baja frecuencia en nuestro país, con sólo pocos casos reportados. La confirmación diagnóstica es con biopsia e inmunohistoquímica. La cirugía sugerida en la literatura es la resección anterior baja, la que se realiza en este caso con buenos resultados. (AU)

Introduction: Leiomyosarcomas (LMS) are rare digestive tract tumors. It is a malignant tumor originated from smooth muscle cells, representing only 0.1% of the total. Rectal location is given in 11% of LMS, however, they represent less than 1% of all malignant colon tumors. It is a very infrequent tumor in our medium. Objective: Show the diagnostic method, treatment, and surgical result. Case Presentation: A 53-year-old female, treated in Padre Hurtado Hospital, heavy smoker, presented with a 1-year history of perianal pain, difficulty during defecation, and three episodes of rectal bleeding. Digital rectal examination showed a mass 4 cm from the anal margin of approximately 2 cm, of irregular surface, and very hard consistency. A colonoscopy was performed, objectivating the tumoral mass and taking a biopsy which was informed as a rectal LMS, including immunohistochemistry results. Continuing with the study, a CT-Scan and MRI were performed. Treatment of choice was surgery; a low anterior resection was carried out with no incidents during the surgery and a favorable post-operatory. LMS is extremely infrequent in our country, with only a few cases reported. Conclusion: Diagnostic confirmation is made through biopsy and immunohistochemistry. Surgery suggested by literature is low anterior resection, which was carried out in this case with good results. (AU)

Disponibilidad de técnicas moleculares para niños con tumores de difícil caracterización. Un problema en la Oncopatología pediátrica. Aplicación y difusión de técnicas de diagnóstico complementarias en el ámbito público / Availability of molecular techniques for children with difficult-to-characterize tumors. A problem in pediatric oncopathology. Application and diffusion of complementary diagnostic techniques in the public setting

La revolución de la biología molecular y el desarrollo de la investigación biomédica básica para el diagnóstico y posterior manejo del cáncer infantil han llevado a la necesidad de organización de grupos interdisciplinarios de profesionales, los cuales se encargan de afrontar los nuevos desafíos diagnósticos y terapéuticos. Los sarcomas indiferenciados pediátricos constituyen un grupo heterogéneo de neoplasias malignas de aspecto primitivo y polifenotípico. La categorización de gran parte de este tipo de tumores es posible gracias a la aplicación de técnicas moleculares complementarias al estudio histopatológico. El objetivo del presente estudio fue recategorizar sarcomas indiferenciados mediante la implementación de una nueva metodología diagnóstica. Se efectuaron técnicas de inmunohistoquimica (IHQ), FISH de interfase y RT-PCR a partir de tejido fijado en formol e incluido en parafina en 144 casos de sarcomas indiferenciados. Se logró la recategorización del 95.1% de los casos, arribando a 24 diagnósticos diferentes. Sólo un 4.9% permanece aún como sarcoma indiferenciado o inclasificable. Los resultados alcanzados por este estudio demuestran la importancia de contar con nuevas herramientas diagnósticas a nivel molecular y recursos humanos especializados que posibiliten su correcta implementación para el diagnóstico de neoplasias de difícil caracterización (AU)

The revolution of molecular biology and the development of basic medical research for the diagnosis and subsequent management of childhood cancer have led to a need to organize interdisciplinary groups of professionals in charge of facing new diagnostic and treatment challenges. Childhood undifferentiated sarcomas are a heterogeneous group of malignant neoplasms that are primitive in appearance and have polyphenotypic features. Categorization of a large part of this type of tumor has become possible with molecular techniques as a complement to histopathological studies. The aim of this study was to categorize undifferentiated sarcomas using new diagnostic tools. Immunohistochemistry (IHC), interfase FISH, and RT-PCR techniques were used on formalin-fixed and paraffin-embedded tissues of 144 cases of undifferentiated sarcomas. Overall, 95.1% of the cases could be recategorized resulting in 24 different diagnoses. In only 4.9% the diagnosis of undifferentiated or unclassifiable sarcoma was maintained. These results emphasize the importance of the availability of new diagnostic tools at the molecular level and specialized human resources enabling adequate implementation for the diagnosis of difficult-to-characterize neoplasms (AU)

Low occurrence of equine herpesvirus 1 (EHV-1) as cause of abortion and perinatal mortality in Brazil / Baixa ocorrência de herpes-vírus equino 1 (HVE-1) como causa de abortamento e mortalidade perinatal no Brasil

Equine herpesvirus type 1 (EHV-1) is an important pathogen that causes abortion, neonatal disease, respiratory disorders, and neurological syndrome in equine populations worldwide. To evaluate EHV-1 as a cause of abortion and perinatal mortality in Brazil, tissue samples from 105 aborted equine fetuses, stillbirths, and foals up to one month of age were examined using virus isolation, immunohistochemistry (IHC), histopathology, and nested polymerase chain reaction (PCR). Two fetuses were positive for EHV-1 by PCR, one of which showed syncytia and eosinophilic intranuclear inclusion bodies in bronchial epithelia, but it was negative by virus isolation. The other showed no characteristic histological lesions, but it was positive by viral isolation. No sample was positive by IHC. The results presented low occurrence of EHV-1 in the studied population and suggested that the use of a combination of techniques increases the likelihood of an accurate diagnosis of EHV-1.(AU)

O herpes-vírus equino tipo 1 (HVE-1) é um importante agente patogênico causador de aborto, doença neonatal, distúrbios respiratórios e síndrome neurológica em populações de equinos em todo o mundo. Para avaliar a ocorrência do HVE-1 como agente causal de abortamento e mortalidade perinatal no Brasil, foram examinadas amostras de 105 fetos equinos abortados, natimortos e potros de até 1 mês de idade, utilizando as técnicas de isolamento viral, imuno-histoquímica (IHQ), histopatologia e reação em cadeia da polimerase aninhada (nested-PCR). Dois fetos foram positivos na análise de PCR, e um deles apresentou corpúsculos de inclusão viral eosinofílicos e sincícios no epitélio brônquico, porém foi negativo na análise de isolamento viral. O outro feto não apresentou lesões histológicas características de infecção herpética, mas foi positivo na análise de isolamento viral. Nenhuma amostra apresentou resultado positivo pela análise de IHQ. Os resultados demonstraram baixa ocorrência de HVE-1 na população estudada e que o uso de diferentes técnicas diagnósticas aumenta a probabilidade de um diagnóstico preciso para o HVE-1.(AU)