RESUMO
OBJECTIVE: To analyze the immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenomas and non-neoplastic mucosa. METHODS: 72 individuals were subjected to colonoscopy, which provided 50 samples of adenomas and 45 samples of non-neoplastic colorectal mucosa. The tissue samples were obtained via the tissue microarray technique and subjected to immunohistochemical analysis using primary anti-p53, anti-COX-2, and anti-caspase-3 antibodies. The positivity and intensity of the immunoreaction were classified. The analyzed variables were as follows: site of the adenomas in the colon, degree of dysplasia, size, and score of positivity and intensity of immunoexpression of the p-53, caspase-3, and COX-2 proteins. RESULTS: The immunoexpression of mutated protein p53 was positive in 30 (60%) adenoma samples and negative in 20 (40%) adenoma samples. The immunoexpression of mutated protein p53 was negative in 39 (86.6%) samples and positive in 6 (13.3%) samples of the non-neoplastic colorectal mucosa (p<0.0001). Significant differences were seen between both the largest size (p=0.006) and the highest degree of dysplasia (p<0.0001) of the adenomas and the intensity of immunoexpression of mutated protein p53. The positivity and intensity of immunoexpression of COX-2 (p=0.14) and caspase-3 (p=0.23) showed no significant differences between the adenomas and the non-neoplastic colorectal mucosa. CONCLUSION: Mutated protein p53 was hyperexpressed in the adenomas compared with the non-neoplastic mucosa. Greater size and greater degree of dysplasia in the adenomas were associated with higher expression of mutated protein p53. The immunoexpression of COX-2 and caspase-3 in the adenomas did not exhibit a correlation with the anatomical-pathological features of the tumors and did not differ from the corresponding expression levels in the non-neoplastic mucosa.
Assuntos
Adenoma/metabolismo , Caspase 3/metabolismo , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
OBJETIVO: Analisar a imunoexpressão das proteínas COX-2, p53 e caspase-3 em adenomas colorretais e na mucosa não neoplásica. MÉTODOS: Foram submetidos à colonoscopia 72 indivíduos que forneceram 50 amostras de adenomas e 45 de mucosa colorretal não neoplásica. Os tecidos foram obtidos pela técnica de arranjo em matriz (tissue microarray) e submetidos a estudo imunoistoquímico com anticorpos primários p53, COX-2 e caspase-3. A positividade e intensidade da imunorreação foram classificadas. Foram estudadas as seguintes variáveis: localização do adenoma no colo, grau de displasia, tamanho, e escores de positividade e intensidade da imunoexpressão das proteínas p-53, caspase-3 e COX-2. RESULTADOS: Nos adenomas, a imunoexpressão da proteína p53 mutada foi positiva em 30 (60%) e negativa em 20 (40%) amostras. Na mucosa colorretal não neoplásica, a imunoexpressão da proteína p53 mutada foi negativa em 39 (86,6%) amostras e positiva em 6 (13,3%) (p<0,0001). Houve diferença significativa entre o maior tamanho (p=0,006) e o maior grau de displasia dos adenomas (p<0,0001) e a intensidade de imunoexpressão da proteína p53 mutada. A positividade e intensidade da imunoexpressão das proteínas COX-2 (p=0,14) e caspase-3 (p=0,23), nos adenomas e na mucosa colorretal não neoplásica, não apresentaram diferença significante. CONCLUSÃO: A proteína p53 mutada é hiperexpressada nos adenomas em comparação com a mucosa não neoplásica. Nos adenomas, o maior tamanho e o maior grau de displasia foram associados à maior expressão da proteína p53 mutada. A imunoexpressão das proteínas COX-2 e caspase nos adenomas não apresentou correlação com os aspectos anatomopatológicos e não foi diferente em termos de níveis de expressão correspondentes na mucosa não neoplásica.
OBJECTIVE: To analyze the immunoexpression of the COX-2, p53, and caspase-3 proteins in colorectal adenomas and non-neoplastic mucosa. METHODS: 72 individuals were subjected to colonoscopy, which provided 50 samples of adenomas and 45 samples of non-neoplastic colorectal mucosa. The tissue samples were obtained via the tissue microarray technique and subjected to immunohistochemical analysis using primary anti-p53, anti-COX-2, and anti-caspase-3 antibodies. The positivity and intensity of the immunoreaction were classified. The analyzed variables were as follows: site of the adenomas in the colon, degree of dysplasia, size, and score of positivity and intensity of immunoexpression of the p-53, caspase-3, and COX-2 proteins. RESULTS: The immunoexpression of mutated protein p53 was positive in 30 (60%) adenoma samples and negative in 20 (40%) adenoma samples. The immunoexpression of mutated protein p53 was negative in 39 (86.6%) samples and positive in 6 (13.3%) samples of the non-neoplastic colorectal mucosa (p<0.0001). Significant differences were seen between both the largest size (p=0.006) and the highest degree of dysplasia (p<0.0001) of the adenomas and the intensity of immunoexpression of mutated protein p53. The positivity and intensity of immunoexpression of COX-2 (p=0.14) and caspase-3 (p=0.23) showed no significant differences between the adenomas and the non-neoplastic colorectal mucosa. CONCLUSION: Mutated protein p53 was hyperexpressed in the adenomas compared with the non-neoplastic mucosa. Greater size and greater degree of dysplasia in the adenomas were associated with higher expression of mutated protein p53. The immunoexpression of COX-2 and caspase-3 in the adenomas did not exhibit a correlation with the anatomical-pathological features of the tumors and did not differ from the corresponding expression levels in the non-neoplastic mucosa.