RESUMEN
Bovine papillomavirus (BPV) is an oncogenic virus related to serious livestock diseases. Oncoproteins encoded by BPV are involved in several steps of cellular transformation and have been reported as presenting clastogenic effects in peripheral lymphocytes and primary culture cells. The aim of this study was to evaluate the clastogenic potential of BPV types 1, 2, and 4 by comet assay. Peripheral blood was collected from 37 bovines, 32 infected with different levels of papillomatosis (12 animals have no affection) and five calves, virus free (negative control). The viral identification showed presence of more than one virus type in 59.375% of the infected animals. Comet assay was performed according to alkaline technique. The Kruskal-Wallis test showed statistical difference between the negative control group and infected animals (P = 0.0015). The Dunn post hoc test showed difference comparing the infected animals with calves. Mann-Whitney U test verified no difference between animals infected with only one viral type and animals presenting more than one viral type. The comet assay is considered an efficient tool for assessment of damage in the host chromatin due to viral action, specifically highlighting viral activity in blood cells.
Asunto(s)
Papillomavirus Bovino 1/aislamiento & purificación , Mutágenos/aislamiento & purificación , Proteínas Oncogénicas/aislamiento & purificación , Papiloma/genética , Animales , Papillomavirus Bovino 1/genética , Bovinos , Transformación Celular Neoplásica/genética , Ensayo Cometa , Proteínas Oncogénicas/genética , Papiloma/patología , Papiloma/veterinariaRESUMEN
Material and methods: A random sample of 28 large bowel adenomas and 44 carcinomas was studied. Determination of p53 protein was made with an immunohistochemical method using monoclonal antibodies. Patients were followed for a mean of 36 months (range 1 to 100 months). Results: p53 immunostaining was obtained in one adenoma (3.5 percent) and in 18 carcinomas (41 percent, p = 0.01). There were no differences in survival during follow up, between cancer patients that expressed or did not express p53 protein. Conclusions: About half of colorectal tumors have immunohistochemical expression of p53 protein, as published abroad. We did not find a prognostic value for this protein in our sample