Characterization of the apoptotic index in canine mastocytomas.

Introdution: Studies on apoptosis have been described in several neoplasias. Apoptosis is a biological process of programmed cell death that, due to its important role in oncogenesis, may elucidate some aspects. Objective: Detection of apoptosis in canine mastocytoma to determine its relationship with histologic grading, apoptotic index and prognosis. Material and methods: 12 cases of canine mastocytoma, from the analytic files of the Laboratory of Anatomical Pathology of ESAV. Immunohistochemical methods were implemented, using pro- and anti-apoptotic proteins, Bax and Bcl (Santa Cruz, Biotechnology). Results: All mastocytomas included in this study revealed a positive reaction to the tested antibodies, a more intense reaction was found to pro-apoptotic antibody Bax in comparison to the anti-apoptotic antibody Bcl-2. While Bax expression was more intense in grade I mastocytomas, Bcl-2 had a higher expression in grade III mastocytomas, and both, had a weaker expression in grade II. Conclusion: The decrease of Bax and increase of Bcl-2 expression in accordance with increasing histologic grade, suggests an extension in the life of tumor cells, an increase their number and, consequently, tumoral progression. Canine mastocytomas revealed sensitivity with Bax and Bcl-2 markers and may be applied to apoptotic studies in such tumors to consolidate prognosis in relationship to histologic grading.FCT and CI&DETS (PEst-OE/CED/UI4016/2011