ABSTRACT
Resumen El carcinoma tipo-linfoepitelioma pulmonar es una variante rara de carcinoma de células no pequeñas de pulmón, representa aproximadamente 0.7% de todos los casos. Está usualmente asociado con la infección por el virus de Epstein-Barr y es más prevalente en el Sureste de Asia; sin embargo, es extremadamente raro en Améri ca Latina. Informamos el caso de un hombre de 65 años de edad con un carcinoma tipo-linfoepitelioma pulmo nar, que se presentó con tos, disnea y pérdida de peso. La TAC de tórax mostró nódulo mal definido localizado en el pulmón derecho. Se realizó biopsia transtorácica de la lesión, y el estudio microscópico reveló células gran des poligonales dispuestas en mantos, infiltrados por abundantes linfocitos y células plasmáticas, alrededor del intersticio. Las células neoplásicas fueron positivas para citoqueratina 5/6 y p63, y negativas para Napsina A y el factor de transcripción tiroideo 1 (TTF-1). La expre sión de PD-L1 fue positivo (aproximadamente 100%) por inmunohistoquímica; así como el núcleo de las células neoplásicas mediante hibridación in situ para el RNA codificado por el virus de Epstein-Barr (EBER-ISH). El paciente recibió seis ciclos de un esquema combinado de quimioterapia basado en platino (gencitabina/cisplatino) más durvalumab. Presentó progresión de la enfermedad y finalmente murió 9 meses después del diagnóstico.
Abstract Pulmonary lymphoepithelioma-like carcinoma is a rare type of non-small cell lung cancer, it accounts for approximately 0.7% of all cases. It is usually associated with Epstein-Barr virus infection and is more prevalent in Southeast Asia; however, it is extremely rare in Latin America. We present a 65-year-old man with a primary pulmonary lymphoepithelioma-like carcinoma, who presented with cough, dyspnoea and weight loss. Com puter tomographic scan of the thorax showed a nodule localized in the right lung. A transthoracic biopsy of the lung lesion was made and the microscopic obser vation revealed large polygonal cells that proliferated in a nest pattern with infiltration by lymphocytes and plasma cells around the interstitium. The tumour cells were positive for citokeratin 5/6 and p63, and negative for Napsin A and thyroid transcription factor 1 (TTF-1). PD-L1 expression was positive (approximately 100%) in the immunohistochemical study, and the nuclei of the tumour cells were positive for EBV-encoded small RNA in-situ hybridization (EBER-ISH). The patient underwent six cycles of platinum-based combination (gencitabine/ carboplatin) chemotherapy plus durvalumab. He pre sented progression of the disease and finally he died 9 months after diagnosis.
ABSTRACT
La citogenética molecular y los métodos de hibridización in situ (HIS) han revolucionado la comprensión de la estructura, función, organización y evolución de los genes y el genoma, además de permitir identificar la presencia y expresión de agentes patógenos dentro de las células afectadas. La HIS es una técnica que combina la biología molecular y las técnicas de histoquímica para estudiar la expresión de genes en secciones de tejido y preparados citológicos, de tal manera que el ADN o el ARN puedan localizarse rápidamente en una célula específica. La HIS localiza la secuencia específica de un gen in situ y visualiza el producto de la expresión de dicho gen preservando al tiempo la integridad de la célula dentro del tejido que la rodea, lo cual permite dictar interpretaciones anatómicas significativas. Esta técnica es el resultado de una reacción en la cual una sonda marcada se une a una secuencia de ácido nucleico complementarias entre sí. Los métodos de HIS son aplicables en investigación clínica y en patología diagnóstica, siendo muy utilizados para buscar expresión de genes cromosomales o para detectar la presencia de bacterias o virus en tejidos infectados, ya que permiten diferenciar los agentes contaminantes de los verdaderos agentes patógenos en un proceso infeccioso.
Molecular cytogenetics and in situ hybridization (ISH) methods have revolutionized the understanding of the structure, function, organization and evolution of genes and genomes, and allow identifying the presence and expression of pathogens within the affected cells. ISH is a technique that combines molecular biology and histochemical techniques to study gene expression in tissue sections and cytological preparations, so that the DNA or RNA can be quickly located in a specific cell. ISH locates the specific sequence of an in situ gene and displays the result of the expression of said gene while preserving the integrity of the cell in the surrounding tissue, which allows for significant anatomical interpretations. This technique is the result of a reaction in which a labeled probe binds to a nucleic acid sequence, which is complementary. ISH methods are applicable in clinical research and diagnostic pathology, being widely used to search for chromosomal gene expression or to detect the presence of bacteria or viruses in infected tissues, as it makes it possible to differentiate pollutants from real pathogens in an infectious process.
A citogenética molecular e os métodos de hibridização in situ (HIS) têm revolucionado a compreensão da estrutura, função, organização e evolução dos genes e o genoma, além de que permite identificar a presença e expressão de agentes patógenos dentro das células afetadas. A HIS é uma técnica que combina a biologia molecular e as técnicas de histoquímica para estudar a expressão de genes em seções de tecido e preparos citológicos, de tal modo que o ADN ou o ARN possam localizar-se rapidamente em uma célula específica. A HIS localiza a sequência específica de um gene in situ e visualiza o produto da expressão deste gene preservando ao mesmo tempo a integridade da célula dentro do tecido que a rodeia, o que permite ditar interpretações anatômicas significativas. Esta técnica é o resultado de uma reação na qual uma sonda marcada se une a uma sequência de ácido nucleico complementares entre si. Os métodos de HIS são aplicáveis em pesquisa clínica e em patologia diagnóstica, sendo muito utilizados para buscar expressão de genes cromossômicos ou para detectar a presença de bactérias ou vírus em tecidos infectados, já que permite diferenciar os agentes contaminantes dos verdadeiros agentes patogênicos em um processo infeccioso.
ABSTRACT
Objective To observe dynamically the location and time of attachment and invasion of Toxoplasma gondii tachyzoites to murine intestinal mucosa by chromogenic in situ hybridization targeting SAG2 mRNA. Methods Thirty 7- to 8-week-old BALB/c mice were randomly divided into experiment group(24 mice)and control group(6 mice). Each animal in the experiment group was given 2?104 tachyzoites of RH stain in 0.2 ml PBS by intragastric administration and that in the control group was given 0.2 ml PBS. Four mice in the experiment group and one in the control group were sacrificed at 15 min,30 min,1 h,2 h,4 h and 8 h after infection,respectively,and paraffin sections of duodenum,jejunum and ileum were prepared to perform the in situ hybridization with Dig-labeled oligonucleotide probe complementary to SAG2 mRNA of T. gondii. Results Tachyzoites were found on the striated border of small intestine epithelial cells (absorptive cells,goblet cells and endocrine cells),in or between two absorptive cells or in the lamina propria. At 15 min-2 h after infection,there was significant difference in the number of attachment on jejunum and ileum (P