Fibrosis in canine transmissible venereal tumor after chemotherapy with vincristine.

The canine transmissible venereal tumor is type of transmissible cancer that occurs naturally through allogenic cellular transplants. Commonly diagnosed in the genital area of sexually active dogs, the tumor typically responds well to vincristine sulfate chemotherapy, although there are cases of resistance to the drug correlated with the tumoral phenotype. We describe herein a case of fibrosis in an area affected by the tumor in a dog after vincristine chemotherapeutic treatment that was associated with an idiosyncratic reaction to the drug.

O tumor venéreo transmissível canino é um tipo de câncer transmissível que ocorre naturalmente através do transplante celular alogênico. Comumente diagnosticado na área genital de cães sexualmente ativos, o tumor normalmente responde bem à quimioterapia com sulfato de vincristina, embora existam casos de resistência à droga correlacionados com o fenótipo tumoral. Descrevemos neste relato de caso um cão com fibrose na área acometida pelo tumor após o tratamento quimioterápico com vincristina associado a uma reação idiossincrática à droga.

Immunophenotypic and molecular profile of cancer stem-cell markers in ex vivo canine transmissible venereal tumour (CTVT).

BACKGROUND: Several studies have attempted to characterise the origin of canine transmissible venereal tumour (CTVT). However, the participation of cancer stem cells (CSC) has not been reported OBJECTIVES: Herein we describe the expression patterns of CSC markers CD44, CD34, CD90 and CD133 in CTVT METHODS: Thirty-eight samples were selected and assessed through flow cytometry and immunohistochemistry RESULTS AND CONCLUSIONS: Twenty-two tumours were classified as plasmacytoid and 16 as mixed. Almost all tumours showed high CD44 and low CD34 levels. CD133 and CD90 expression varied among tumours. Cytological groups did not differ in the proportion of CSC markers. Our results suggest that CSC subpopulations might participate in CTVT.

Osteopontin expression and its relationship with prognostic biomarkers in canine mammary carcinomas / Expressão de osteopontina e sua relação com biomarcadores prognóstico nos carcinomas mamários caninos

Osteopontin is a glycophosphoprotein implicated in different physiologic and pathologic processes and is known to be involved in progression and metastasis of various cancers in humans, but this relation is still little explored in the veterinary. The aim was to evaluate the expression of osteopontin in canine mammary carcinomas and its relation with well-established canine mammary tumor biomarkers. For that, expression of OPN, EGFR, HER2, and c-Kit were evaluated along with Ki67 rate in 43 mammary carcinomas. Osteopontin was demonstrated to be expressed by neoplastic epithelial cells in all carcinomas as well as in stromal cells from the tumor microenvironment. Relation between high osteopontin expression and EGFR positivity (P<0.001) and HER2 overexpression (P=0.012) was demonstrated. In conclusion, high OPN expression seems to be related to poor prognosis and MAPK pathway activation, given the association with EGFR and HER2, members of the MAPK signaling pathway.(AU)

A osteopontina é uma glicofosfoproteina implicada em diferentes processos fisiológicos e patológicos, sendo conhecida por estar envolvida na progressão e metástase de vários cânceres nos humanos, no entanto, essa relação é ainda pouco explorada na veterinária. O objetivo deste trabalho foi avaliar a expressão da osteopontina nos carcinomas mamários caninos e sua relação com biomarcadores bem estabelecidos para esta neoplasia. Para isto, foi avaliada a expressão de OPN, EGRH, HER2 e c-Kit juntamente com a taxa de Ki67 em 43 carcinomas mamários. A osteopontina foi expressa pelas células epiteliais neoplásicas em todos os carcinomas, assim como, nas células estromais do microambiente tumoral. Foi demonstrada uma relação entre uma alta expressão de osteopontina e positividade para EGFR (P<0.001) e superexpressão de HER2 (P=0.012). Em conclusão, alta expressão de OPN parece estar relacionada com mau prognóstico e ativação da via MAPK, devido a sua associação com EGRF e HER2, os quais são membros desta via de sinalização.(AU)

The role of the multi-drug resistance 1, p53, b cell lymphoma 2, and bcl 2-associated X genes in the biologic behavior and chemotherapeutic resistance of canine transmissible venereal tumors.

BACKGROUND: Canine transmissible venereal tumors (CTVTs) generally have different cytomorphologic subtypes and phases of progression. Some tumors have variable biologic behavior including a progressive increase in tumor aggressiveness and variable responses to chemotherapy. This behavior is partially due to high p-glycoprotein expression by tumor cells, which leads to the expulsion of chemotherapeutic drugs. Other possible causes include changes in pro- and anti-apoptotic genes from the BCL-2 family and DNA repair systems, which are associated with the p53 gene family. OBJECTIVES: We aimed to determine the relative expression of the multi-drug resistance 1 (MDR1), p53, b-cell lymphoma 2 (BCL2), and bcl 2-associated X (BAX) genes in CTVT before and after therapy and establish a relationship with treatment responses, cytomorphologic patterns, and tumor progression identified with histopathology. METHODS: RT-qPCR was performed on 21 CTVT tumor samples before and after initiating chemotherapy to determine specific gene expression. Normal canine testicular tissue was used as a negative control for all experiments. RESULTS: MDR1 expression was decreased before and after initiating vincristine therapy in CTVT tumor tissues compared with normal canine testicular tissue; p53 and BAX were overexpressed at both time points compared with normal tissue, and no statistical differences were seen between the different morphologic types. However, BAX expression was decreased in the group with quick therapeutic responses but was still overexpressed compared with normal testicular tissue. In the group with the slowest chemotherapeutic responses, BCL2 was overexpressed. CONCLUSION: The findings of this study showed a relative increase in MDR1 gene expression in response to chemotherapy and higher expression in plasmacytoid CTVTs compared with the other cytomorphologic patterns. BCL2 overexpression was related to a favorable prognosis, and p53, BAX, and BCL2 were expressed independent of the cytomorphologic CTVT type. All of the genes were expressed independent of tumor progression, as noted on histopathology.

Canine transmissible venereal tumor: expression of MDR-1, and TP53 and BCL-2 family genes and its implications in biological and therapeutic behavior / Tumor venéreo transmissível canino/: expressão dos genes MDR-1, TP53 e da família Bcl-2 e suas implicações no comportamento biológico e terapêutico / Tumor venéreo transmisible canino: expresión de los genes MDR-1, TP53 y de la familia Bcl-2 y sus implicaciones en el comportamiento biológico y terapéutico

Transmissible venereal tumor (TVT) is a neoplasm of round cells with plasmocytoid or lymphocytoid appearance. The tumor presents several particularities, which have been the subject of numerous studies; however there still have investigations that need to be done. For example, a progressive increase of highly aggressive tumors with varying response to chemotherapy -including resistance- has been evidenced in recent years. There is scientific interest to understand these differences, allowing predicting possible clinical outcomes in affected dogs and increasingly searching adequate and individualized therapy. This review focuses on presenting possible implications of the expression of MDR-1 (P-glycoprotein), TP53, BCL-2, and BAX genes, regarding resistance to chemotherapy and/or the biologic behavior of TVT.

O tumor venéreo transmissível (TVT) é uma neoplasia de células redondas de aspecto plasmocitóide ou linfocitóide. O tumor apresenta várias particularidades que tem sido objeto de numerosas investigações e apesar disso, ainda existem lacunas que necessitam de maiores estudos. Por exemplo, nos últimos anos, tem-se evidenciado um aumento progressivo de tumores que apresentam elevados porcentuais de agressividade e variável resposta à quimioterapia, inclusive resistência. Desta forma, atualmente há interesses científicos com relação a compreender melhor estas diferenças, permitindo predizer uma possível evolução clínica entre cães acometidos pelo tumor e buscando cada vez mais uma conduta terapêutica adequada e individualizada. Assim, a revisão de literatura, centra-se em apresentar possíveis implicações da expressão dos genes MDR-1 (glicoproteína-p), TP53, BCL-2, BAX, quanto à resistência à quimioterapia, e/ou comportamento biológico do TVT.

El tumor venéreo transmisible (TVT) es una neoplasia de células redondas de aspecto plasmocitoide o linfocitoide. El tumor presenta varias particularidades que han sido objeto de numerosas investigaciones y a pesar de eso, aún existen algunos vacíos en su conocimiento que requieren mayores estudios. Por ejemplo, en los últimos años, se ha evidenciado un aumento progresivo de tumores que presentan elevados porcentajes de agresividad y una respuesta variable a la quimioterapia, inclusive alguna resistencia. En este sentido, actualmente hay intereses científicos con relación a comprender mejor estas diferencias, permitiendo predecir una posible evolución clínica entre perros afectados por el tumor y buscando cada vez más una conducta terapéutica adecuada e individualizada. Así, la revisión de literatura, se centra en presentar posibles implicaciones de la expresión de los genes MDR-1 (glicoproteína-p), TP53, BCL-2, BAX, en cuanto a la resistencia a la quimioterapia, y/o el comportamiento biológico del TVT.

Uso de la inmunohistoquímica como herramienta epidemiológica para el diagnóstico de rabia bovina a partir de casos no conclusivos / Use of immunohistochemistry as an epidemiological tool for the diagnosis of bovine rabies using inconclusive cases

Objetivo. Identificar el virus de la rabia en casos de encefalitis bovina a partir de muestras archivadas en el laboratorio sin diagnóstico conclusivo. Materiales y métodos. Doce muestras de cerebro bovino sospechosas de rabia, fueron procesadas por la técnica de inmunoperoxidasa indirecta, usando anticuerpos policlonales contra el agente viral. Resultados. Se demostró la presencia de antígenos virales en tres casos en forma de agregados pequeños en el citoplasma de las neuronas, con un patrón de forma redonda u oval y un número variable de corpúsculos de inclusión viral. Se discute sobre la importancia de los resultados en Colombia, la utilidad de la técnica en las difíciles condiciones de envío de muestras al laboratorio, además la posible relación de los casos negativos con herpesvirus bovino 5. Conclusiones. La utilización de la técnica de inmunohistoquímica para demostrar antígenos del virus rábico en encéfalos bovinos fijados en formol, puede ayudar en el perfeccionamiento del mapa epidemiológico de la enfermedad de la rabia en Colombia y puede disminuir el alto subdiagnóstico de otras enfermedades que afectan el sistema nervioso de los bovinos.

Objective. Identify the rabies virus in cases of nervous disease archived in the laboratory with diagnosis of nonspecific encephalitis. Materials and methods. Twelve samples of bovine brain suspected of rabies, were processed by indirect immunoperoxidase technique using polyclonal antibodies against the viral agent. Results. Was demonstrated the presence of viral antigens in three cases in the form of small aggregates in the cytoplasm of neurons, with a pattern of round or oval and a variable number of viral inclusion bodies. We discussed the importance of the results in Colombia, the usefulness of the technique in the difficult conditions for sending samples to the laboratory, plus the possible relationship of the negative cases with bovine herpesvirus 5. Conclusions. The use of immunohistochemical technique to demonstrate rabies virus antigens in formalin fixed bovines tissues can help in the construction of an epidemiological map of rabies disease in Colombia and may reduce the high under-diagnosis of diseases of the nervous system of cattle, reported in some regions.

Intoxicación con fenilbutazona en un equino: reporte de un caso / Toxicity with phenylbutazone in a horse: a case report

Se describe el caso de un equino que desarrolló graves lesiones digestivas después de recibir dosis altasde fenilbutazona (FBZ) para tratar una claudicación. Al momento de la consulta tenía 9 días de evolución.Desde su llegada al hospital, se observó cojera grave de las cuatro extremidades, deshidratación y diarreafétida. Luego del examen físico, la anamnesis y las ayudas diagnósticas se propuso un dictamen de laminitis traumática, gastritis ulcerativa y colitis por intoxicación con antiinflamatorios no esteroides (AINES). Lacondición empeoró a pesar de la terapia y cuando se presentaron signos neurológicos se sugirió la eutanasia.Durante la necropsia se observaron lesiones graves en el tracto gastrointestinal, cascos y encéfalo. El objetivo de este artículo es describir la sintomatología, terapia y evolución de un paciente intoxicado con aines.

It is described a clinic case of an equine that developed severe digestive lesions after taking high dosage ofphenylbutazone to treat a lameness. At the moment of checking, it had nine days of evolution. Since its arrivingto the hospital, it was seen an intense lameness of the four limbs, dehydration and fetid diarrhea. After the physicexam, the interrogatory and the diagnostic aids it was proposed a diagnosis of traumatic laminitis, ulcerative gastritis and colitis by intoxication with Non-steroidal anti-inflamatory drug (NSAIDs). The condition became worse despite the therapy and when the neurological signs were presented. It was suggested the euthanasia. During the necropsy, it was seen severe lesions in the gastrointestinal tract, hooves and brain. The objective of this article is to describe la symptomatology, therapy and evolution of the intoxicated patient with NSAIDs.

Descreve-se o caso de um cavalo que desenvolveu lesões digestivas graves após receber altas doses defenilbutazona (FBZ) para tratar uma claudicação. No momento da consulta havia 9 dias de evolução. Desdesua chegada ao hospital, observou-se manqueira grave nas quatro extremidades, desidratação e diarréia fétida. Após o exame físico, a anamnese e os meios diagnósticos concluiu-se se tratar de laminite traumática, gastriteulcerativa e colite por intoxicaçãocom anti-inflamatórios não esteróides (AINES). A condição piorou apesardo tratamento e, quando apresentou sinais neurológicos, sugeriu-se a eutanásia. Na necrópsia observaram-selesões graves no trato gastrointestinal, cascos e enféfalo. O objetivo deste trabalho é descrever os sintomas, otratamento e a evolução de um paciente intoxicado com AINES.