Large-scale gene and microRNAs expression study of bitches breast carcinomas and metastatic regional lymph nodes

Abstract

Canine mammary tumor is the most common tumor in bitches and their biological and molecular behavior resembles what occurs in women, so bitches can be an excellent comparative model for understanding the carcinogenic process of this neoplasm. Metastasis is a common consequence and the leading cause of mortality from this disease in both species. One of the most common histological type of bitches carcinoma is carcinoma in mixed tumor. This is an uncommon tumor in women, making the dog a good natural model to study this type of neoplasia. Moreover, the frequency of metastasis of this histological type is low when compared to the simple carcinomas, interesting fact, since carcinomas in mixed tumor phenotype have an epithelial mesenchymal transition (EMT) that knowingly facilitates and supports the metastatic process. Faced with this fact, we propose to identify genes and microRNAs differentially expressed in simple and mixed tumor carcinomas of bitches and in regional lymph nodes with and without metastasis, using the large scale gene expression technique array platforms, and thus recognize the molecular mechanisms involved in the processes of EMT and metastatic potential. The results will be validated by RT-qPCR and immunohistochemistry method. The data will also be compared with clinical and histopathological parameters. (AU)