Probiotic Enterococcus faecium CRL 183 inhibit chemically induced colon cancer in male Wistar rats

Several animal studies have shown that supplementation with specific strains of lactic acid bacteria could prevent the establishment, growth, and metastasis of transplantable and chemically induced tumors. The goal of this study was to determine the effect of Enterococcus faecium CRL 183 on the incidence of colorectal tumors induced experimentally by dimethylhydrazine (DMH). We used thirty 4-week old male Wistar rat. The animals belonging to the DMH groups were injected s.c 20 mg/kg body weight of 1,2 dimethylhydrazine and 1 mM EDTA (pH 6.5), in a weekly dose, for 14 weeks. Three groups were used: (1) Control (not initiated); (2) Initiated with DMH; (3) Initiated with DMH + intake of E. faecium CRL 183. At the end of the 42nd week, all the animals were euthanized; the colons were removed and analyzed histologically. All the groups were compared histologically and IL-4, IFN-gamma and TNF-alpha cytokines. The control group did not develop pre-neoplastic lesions. The E. faecium CRL 183-DMH group showed a 50% inhibition in incidence in average number of tumors (P < 0.001), reduced the formation of ACF (P < 0.001), the lowest number of adenocarcinoma being found in this group (P < 0.001) and enhanced the immune response by increasing IL-4, IFN-gamma and TNF-alpha (P < 0.001) when compared with the DMH group.

Protective effects of lemongrass (Cymbopogon citratus STAPF) essential oil on DNA damage and carcinogenesis in female Balb/C mice

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

The role of the TP53 gene during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide

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

Immunohistochemical and morphological features of a small bowel leiomyoma in a black crested macaque (Macaca nigra)

Background: Spontaneous gastrointestinal neoplasms in non-human primates are commonly seen in aged individuals. Due to genetic similarities between human and non-human primates, scientists have shown increasing interest in terms of comparative oncology studies.Case presentation: The present study is related to a case of an intestinal leiomyoma in a black crested macaque (Macaca nigra), kept on captivity by Mateca a Zoo, Pereira City, Colombia. The animal had abdominal distension, anorexia, vomiting, diarrhea and behavioral changes. Clinical examination showed an increased volume in the upper right abdominal quadrant caused by a neoplastic mass. The patient died during the surgical procedure. Necropsy revealed several small nodules in the peritoneum with adhesion to different portions of the small and large intestines, liver, stomach and diaphragm. Tissue samples were collected, routinely processed and stained by H&E. Microscopic examination revealed a mesenchymal tumor limited to tunica muscularis, resembling normal smooth muscle cells. Neoplastic cells were positive for alpha-smooth muscle actin and vimentin, and negative for cytokeratin AE1/AE3 by immunohistochemistry. Those morphological and immunohistochemical findings allowed to diagnose the intestinal leiomyoma referred above.Conclusion: Neoplastic diseases in primates have multifaceted causes. Their manifestations are understudied, leading to a greater difficulty in detection and measurement of the real impact provides by this disease.

Microdissecção e captura a laser na investigação do gene TP53 em tecidos incluídos em parafina

INTRODUÇÃO: Microdissecção e captura a laser (MCL) é uma técnica de desenvolvimento recente que permite a coleta de células individuais ou pequeno conjunto de células para análise molecular. Atualmente, no Brasil, há raros microscópios para MCL, de modo que a divulgação dos procedimentos inerentes a essa técnica é oportuna para destacar seu amplo potencial para diagnóstico e investigação. OBJETIVO: Este trabalho descreve a padronização dos procedimentos de MCL e de extração de DNA de material fixado em formalina e incluído em parafina. MATERIAL E MÉTODOS: Foram estudados o éxon 8 do gene TP53 e o gene da ciclofilina em amostras de tecido normal e de neoplasias de fígado e rim provenientes de modelo de carcinogênese química induzida em rato. A extração do DNA foi comprovada por reação em cadeia da polimerase (nested-PCR). RESULTADOS: Foram padronizados os procedimentos de preparo dos cortes histológicos, de microdissecção e captura a laser e de obtenção de seqüências gênicas pela reação de nested-PCR para tecidos incluídos em parafina. Obtivemos amplificação de 48,3% das amostras para o éxon 8 do gene TP53 e 51,7% para o gene da ciclofilina. Considerando pelo menos um dos dois segmentos gênicos, foram amplificadas 79,3% das amostras. DISCUSSÃO E CONCLUSÃO: A extração de DNA de tecidos fixados em formalina e incluídos em parafina e a técnica de nested-PCR foram adequadamente padronizadas para produtos gênicos de interesse, obtidos de material coletado por MCL. Esses procedimentos podem ser úteis para a obtenção de seqüências de DNA de arquivos para análise molecular.

Exame citológico em medicina veterinária: estudo retrospectivo de 11.468 casos (1994-2008)

Foi realizado um estudo retrospectivo dos resultados dos exames citológicos provenientes dos arquivos do Serviço de Citopatologia do Laboratório de Patologia Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, São Paulo, entre janeiro de 1994 e dezembro de 2008. do total de 139.986 animais atendidos no Hospital Veterinário da instituição, 11.468 (8,2%) foram encaminhados para exame citológico. Desses diagnósticos, 57,28% corresponderam a lesões neoplásicas, 19,28% a lesões inflamatórias e 14,79% a processos não neoplásicos (imunológicos, degenerativos, hiperplásicos ou displásicos). Não foi possível concluir o diagnóstico por meio do exame citológico em 7,28% dos casos e não haviam informações diagnósticas registradas em 1,37% dos casos. Dentre os animais que mais receberam indicação para exame citológico destacaram-se os caninos (92,06%), seguidos pelos felinos (4,08%), bovinos (1,77%) e equinos (1,30%). Lesoes neoplásicas foram as mais comumente observadas e foram mais prevalentes nos cães (59,18%), afetando principalmente animais com idade média de 119,60 meses e principalmente fêmeas (61,61%). O incremento anual observado ao longo dos 15 anos de aplicação da citologia demonstra que o exame citológico é um método de suma importância para confirmar, sugerir ou afastar o diagnóstico de diversas afecções, inclusive neoplasia, em todas as espécies animais.

Multicentric lymphoma with metastasis in the central nervous system in a dog

Linfoma multicêntrico foi diagnosticado em um cão com dois anos de idade que apresentava insuficiência respiratória, aumento de volume abdominal (ascite) e linfoadenopatia generalizada. O exame imunoistoquímico revelou origem de células T com expressão CD3+ e CD79-. Após cinco semanas, o cão apresentou déficits neurológicos progressivos, sendo identificada a presença de linfócitos neoplásicos no líquor. O exame histopatológico demonstrou invasão de células neoplásicas no baço, linfonodos, cérebro e cerebelo.

Malignant mammary tumor in female dogs: environmental contaminants

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Extramedullary hematopoiesis in a case of benign mixed mammary tumor in a female dog: cytological and histopathological assessment

Backgroud: Extramedullary hematopoiesis (EMH) is defined as the presence of hematopoietic stem cells such as erythroid and myeloid lineage plus megakaryocytes in extramedullary sites like liver, spleen and lymph nodes and is usually associated with either bone marrow or hematological disorders. Mammary EMH is a rare condition either in human and veterinary medicine and can be associated with benign mixed mammary tumors, similarly to that described in this case.Case presentation: Hematopoietic stem cells were found in a benign mixed mammary tumor of a 7-year-old female mongrel dog that presents a nodule in the left inguinal mammary gland. The patient did not have any hematological abnormalities. Cytological evaluation demonstrated two distinct cell populations, composed of either epithelial or mesenchymal cells, sometimes associated with a fibrillar acidophilic matrix, apart from megakaryocytes, osteoclasts, metarubricytes, prorubricytes, rubricytes, rubriblasts, promyelocytes, myeloblasts. Histological examination confirmed the presence of an active hematopoietic bone marrow within the bone tissue of a benign mammary mixed tumor.Conclusions: EMH is a rare condition described in veterinary medicine that can be associated with mammary mixed tumors. It's detection can be associated with several neoplastic and non-neoplastic mammary lesions, i.e. osteosarcomas, mixed tumors and bone metaplasia.

Cutaneous myxosarcoma in a Syrian hamster (Mesocricetus auratus)

The pathological findings in a 2-years-old Syrian hamster (Mesocricetus auratus) with a cutaneous myxosarcoma are described. Grossly, there was a large cutaneous mass in the right cervical region. Microscopical evaluation revealed a myxosarcoma characterized by pleomorphic, fusiform cells loosely arranged, randomly distributed, and presenting a moderate amount of basophilic amorphous stroma. There were hemorrhagic areas within the tumor. The basophilic amorphous stroma was positive to Alcian blue confirming the presence of a mucopolysaccharide matrix. Immunohistochemically, the neoplastic cells expressed vimentin, and were negative for cytokeratin or glial fibrillary acidic protein (GFAP).

Peripheral Ossifying Fibroma

The peripheral ossifying fibroma (POF) is a common gingival growth usually arising from the interdental papilla. The anterior maxilla is the most common location of involvement. The etiology and pathogenesis of POF remains unknown. Some investigators consider it a neoplastic process, whereas others argue that it is a reactive process; in either case, the lesion is thought to arise from cells in the periodontal ligament. Trauma or local irritants, such as dental plaque, calculus, microorganisms, masticatory force, ill-fitting dentures, and poor quality restorations, have been implicated in the etiology of POF. The recommended treatment is the excisional biopsy; however, it can leave a defect if the procedure is not followed by a subepithelial connective tissue graft. The main objective of this article was to present a clinical case of excisional biopsy of a POF followed by a subepithelial connective tissue graft to correct the defect caused by the biopsy. The biopsy defect was satisfactorily repaired, and the lesion has not recurred after 6 years of follow-up.

Prostate carcinogenesis induced by N-methyl-N-nitrosourea (mnu) in gerbils: Histopathological diagnosis and potential invasiveness mediated by extracellular matrix components

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

Methylation profile of genes CDKN2A (p14 and p16), DAPK1, CDH1, and ADAM23 in head and neck cancer

Hypermethylation in the promoter region has been associated with a loss of gene function that may give a selective advantage to neoplastic cells. In this study, the methylation pattern of genes CDKN2A (alias p14, p14(ARF), p16, p16(INK4a)), DAPK1, CDH1, and ADAM23 was analyzed in 43 samples of head and neck tumors using methylation-specific polymerase chain reaction. In the oropharynx, there was a statistically significant association between hypermethylation of the DAPK1 gene and the occurrence of lymph node metastases, and in the larynx there was statistically significant evidence of an association between hypermethylation of the ADAM23 gene and advanced stages of the tumors. Thus, a correlation was observed between hypermethylation of the promoter region of genes DAPK1 and ADAM23 and the progression of head and neck cancer. (c) 2007 Elsevier B.V. All rights reserved.

Detection of numerical chromosome anomalies in interphase cells of benign and malignant thyroid lesions using fluorescence in situ hybridization

Benign and malignant thyroid tumors constitute a wide range of neoplasias showing recurrent chromosome abnormalities. In an attempt to characterize specific numerical chromosome abnormalities in thyroid tissues, We present here the findings from a study of archival samples depicted by 10 malignant tumors, 30 benign lesions, and 10 normal thyroid tissues. Fluorescence in situ hybridization was performed on noncultured samples using biotinylated centromere-specific probes for chromosomes 7, 10, and 17. Trisomy or tetrasomy 7 were present in 19 benign and in 7 malignant tumors. Trisomy 10 or 17 were observed in 18 adenomas or goiters and in 9 carcinomas, and monosomy 17 was seen in 2 carcinomas. Our findings suggest that such abnormalities are an in vivo phenomenon and may be important in the neoplastic proliferation of thyroid gland. (C) Elsevier B.V., 2000. All rights reserved.

Gene expression profiling reveals molecular marker candidates of laryngeal squamous cell carcinoma

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