Evaluation of CD44, CD24, Oct3/4 and c-Myc expression and its relation with clinical-pathological data in inflammatory mammary carcinoma from female dogs

Abstract

Inflammatory mammary carcinoma (IMC) of the female dog is considered a study model of the same condition in humans due its clinical, etiological and pathological similar features to human inflammatory breast cancer. It is the most aggressive histological subtype of the mammary tumor and is associated with worse prognosis in both species. Currently, different studies have been identifying a subpopulation of cells with similar characteristics to stem cells, with function of initiation and tumor progression. The recognition and analysis of the expression of such cells in tumor tissue samples by the immunohistochemical staining have been used in breast cancer to establish early diagnosis, prognosis, new therapeutic targets and to elucidate molecular pathways of oncogenesis. In the association of prognostic factors with IMC, increased expression of OCT3/4 protein was associated with worsening prognosis after surgical intervention and the presence of metastases in the non-sentinel lymph node. Alterations in C-MYC gene expression are related to chemotherapeutic resistance and the CD44+/CD24- phenotype is a potential therapeutic target and is associated with the aggressive clinical-pathological presentation of the mammary tumor. Comparatively, the study of stem cell expression in the canine species is scarce and the results controversial. Thus, the present study aimed to evaluate the expression of the OCT3/4, CD24, CD44 and C-MYC stem cells markers in IMC samples from dogs, correlating the results obtained with the clinicopathological features.