Desenvolvimento e avaliação comparativa do melanoma oral em camundongos, frente sua ocorrência espontânea em cães

Abstract

Introduction: Melanoma is the most common neoplasm in oral cavity of dogs. Melanoma has a predilection for the gum, and it is characterized by accelerated progression and high rates of relapse, metastasis and resistance to proposed therapies. Those factors inspires the present study, considering the lack of an experimental model for melanoma. Method: This is an experimental study. Thirty C57Bl / 6J mice (Mus musculus) were submitted to tumor induction by injecting murine melanoma B16F10 cells into the right lower gum using two different cell concentrations. Mice were divided in two groups: Group 1 (n = 15) received 1x104 murine melanoma B16F10 cells injection; Group 2 (n = 15) received 5x104 murine melanoma B16F10 cells injections. For both groups, euthanasia was scheduled at the 7th., 14th. and 21th. postoperative day, with post-mortem hemi-resection of the jaw. Individuals who died before the euthanasia period were excluded, leaving 21 mice. Macroscopic analysis of tumor formations was performed. For comparative histological study, oral canine melanoma samples were analyzed for morphological aspects. Data sete analyzed with BioStat 5.3 and submitted to non-parametric statistical tests. Results: Different tumor characteristics (tumor volume, presence of irregular margins, ulceration and dark coloration) were observed for each cell concentration used in the induction, as well perfect correlation between tumor volume and tumor growth. Conclusion: The induction of oral melanoma in mice for purposes of preclinical study model for dogs is an useful, viable and reproducible alternative.