TY - JOUR AU - González, Carlos AU - Cepeda, Raquel AU - Flores, Estefanía AU - Cattaneo, Gino AU - Reyes, Susana PY - 2003/01/01 Y2 - 2024/03/29 TI - Apoptosis en tumor venéreo transmisible del canino en fase de crecimiento progresivo y durante regresión inducida por vincristina JF - Avances en Ciencias Veterinarias JA - Av. cienc. vet. VL - 18 IS - 1-2 SE - Trabajos Originales DO - 10.5354/acv.v18i1-2.9199 UR - https://avancesveterinaria.uchile.cl/index.php/ACV/article/view/9199 SP - AB - <p align="justify"><em>Apoptosis or programmed cell death is a mechanism of cell elimination when they are unnecessary or </em><em>genetically damaged. It is controlled by a variety of genes, many of which present mutation or dysfunstion</em><em> associated to cancer. When this occurs patients have more aggressive tumors. A characteristic DNA fragmentation occurs during apoptosis which can be traced and enzimatically revealed by TÚNEL (ter­minal transference mediaded dUTP-biotin nick end labelling) technique. This allows early apoptosis detection even before the first morphologic nuclear changes take place. In this work 10 adult canine with </em><em>genital TVT were selected to undergo one single doce (0.03mg/Kg) Vincristine sulphate treatment, in arder</em><em>to induce tumor regression. Histological samples were obtained and processed for TÚNEL immune staining.</em><em> Images were digitalized an analyzed by a morphometric software (Image Pro-Plus, Media Cybernetics, USA). The mean area obtained for apoptotic cells was 51.3±37.9mm2 and 1396±828.6mm2/200X field, for progressive and regressive growth, respectively. This indicates a significant dference between both phases (p<0.0001). The main cell type for both tumor stages corresponded to tumor cells with 80,7% for progressive and 89.4% for regressive growth, resulting in a sign ficant augmentation for this latter tumor stage (p<0.001). This results indicate that vincristine induces TVT to collapse through apoptosis. The exact underlying mechanism remains to be demonstrated, however in other neoplams caspasas 9 and 3 </em><em>activation has been described suggesting that the mitochondrial way is involved, through oxgygen derived</em><em> radical production and Bcl-2 gene overexpression.</em></p> ER -