Expressão do Complexo APC, GSK3- β, Axina e βcatenina na carcinogênese bucal quimicamente induzida pela 4-nitroquinolina 1-óxido em ratos
Data
2012-03-16
Autores
Carvalho, Juliana Gonçalves 
Orientadores
Ribeiro, Daniel Araki
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Objetivo: Este estudo teve como objetivo avaliar a imunoexpressão do complexo
APC, GSK-3β, Axina e β-Catenina, componentes da via WNT, durante a
carcinogênese bucal quimicamente induzida pela 4-nitroquinolina 1-óxido em ratos.
Material e métodos: Ratos Wistar machos foram distribuídos em três grupos de 10
animais cada e tratados com 50 ppm de 4NQO administrada na água oferecida no
bebedouro aos animais, durante um período de 4, 12 e 20 semanas. Paralelamente,
foram utilizados 10 animais controle para os respectivos períodos de tratamento.
Foram feitas análises macroscópica, histopatológica e imunoistoquímica da língua
desses animais. Resultados: O grupo exposto a 4NQO por 4 semanas não
apresentou nenhuma alteração macroscópica ou histopatológica quando comparado
ao grupo controle. Os animais expostos por 12 e 20 semanas apresentaram
leucoplasia, lesões ulceradas e exofíticas, bem como, hiperplasia e hiperqueratose
com displasia de grau leve a moderado e carcinoma de células escamosas de tipo
bem diferenciado, respectivamente. A expressão das proteínas APC e Axina
apresentou padrão moderado no grupo controle. Os grupos experimentais
demonstraram uma diminuição em sua expressão quando comparadas ao grupo
controle. GSK-3β, apresentou resultados similares em todos os grupos. Os grupos
controle e 4 semanas apresentaram imunopositividade moderada para a β-Catenina.
Após 12 e 20 semanas de exposição a 4NQO, a expressão foi considerada
altamente positiva, praticamente em todas as camadas do epitélio. Conclusão: A
diminuição da imunopositividade das proteínas APC e Axina aliado ao aumento da
imunoexpressão de β-Catenina estão associados ao risco e a progressão do câncer
bucal.
Objective: This study aimed to determine the expression of the complex APC, GSK3β, Axin and β-Catenin, WNT pathway components during chemically induced oral carcinogenesis by 4-nitroquinoline 1-oxide in rats. Methods: Male Wistar rats were distributed into three groups of 10 animals each and treated with 50 ppm 4NQO administered in the drinking water offered to the animals during 4, 12 and 20 weeks. In parallel, 10 were used to control for the respective periods of treatment. Analysis was made macroscopic, histopathological and immunohistochemical tongue of these animals. Results: The group exposed to 4NQO for 4 weeks showed no gross or histopathological changes compared to the control group. Animals exposed for 12 and 20 weeks showed leukoplakia, exophytic and ulcerated lesions, as well as hyperplasia and hyperkeratosis with mild dysplasia and moderate squamous cell carcinoma of well differentiated type, respectively. The APC protein expression pattern and Axin presented moderate in the control group. The experimental groups showed a decrease in expression when compared to the control group. GSK-3β showed similar results for all groups. The control group and 4 weeks showed moderate immunopositivity for β-Catenin. After 12 and 20 weeks of exposure to 4NQO, the expression was considered highly positive in all layers of the epithelium. Conclusion: The decrease in protein immunopositivity Axin and APC, combined with the increased immunoexpression of β-catenin are associated with risk and progression of oral cancer.
Objective: This study aimed to determine the expression of the complex APC, GSK3β, Axin and β-Catenin, WNT pathway components during chemically induced oral carcinogenesis by 4-nitroquinoline 1-oxide in rats. Methods: Male Wistar rats were distributed into three groups of 10 animals each and treated with 50 ppm 4NQO administered in the drinking water offered to the animals during 4, 12 and 20 weeks. In parallel, 10 were used to control for the respective periods of treatment. Analysis was made macroscopic, histopathological and immunohistochemical tongue of these animals. Results: The group exposed to 4NQO for 4 weeks showed no gross or histopathological changes compared to the control group. Animals exposed for 12 and 20 weeks showed leukoplakia, exophytic and ulcerated lesions, as well as hyperplasia and hyperkeratosis with mild dysplasia and moderate squamous cell carcinoma of well differentiated type, respectively. The APC protein expression pattern and Axin presented moderate in the control group. The experimental groups showed a decrease in expression when compared to the control group. GSK-3β showed similar results for all groups. The control group and 4 weeks showed moderate immunopositivity for β-Catenin. After 12 and 20 weeks of exposure to 4NQO, the expression was considered highly positive in all layers of the epithelium. Conclusion: The decrease in protein immunopositivity Axin and APC, combined with the increased immunoexpression of β-catenin are associated with risk and progression of oral cancer.
Descrição
Citação
CARVALHO, Juliana Gonçalves. O binômio esporte-saúde sob a ótica de profissionais de educação física. 2012. 94f. Dissertação (Mestrado) - Instituto Saúde e Sociedade, Universidade Federal de São Paulo, Santos, 2012.