Cross species validation of exosomal biomarkers, for early diagnosis and prognosis of triple negative breast cancer

Abstract

The canine breast tumor (TM) is a valuable clinical model for breast cancer (CM) in women because it shares etiological, clinical, histopathological, molecular and prognostic similarities with the disease in humans. The combination of the dogs' inherently shorter life expectancy, the manifestation of spontaneous disease and the multifactorial etiology, allows for improved data collection and facilitates the development of a pragmatic clinical model. In addition, a comparison of the proteomics of circulating exosomes between patients with breast cancer of these two species has never been performed. The liquid biopsy as a reliable platform for the discovery of candidate proteins for biomarkers of CM may determine the early diagnosis and prognosis for both species. In this study, we propose to isolate exosomes extracted from the serum of canine females and women, with a diagnosis of triple-negative breast cancer, at different stages of the disease (pre and post surgery, metastasis and remission). Then, investigate the exosomal proteomic load by means of mass chromatography (LC-MS / MS) and compare it with that observed in exosomes of healthy and cured patients, correlating these findings with the histological and phenotypic classification, degree and stage disease. We will seek to verify the findings of proteomics for the identification of candidate proteins for tumor biomarkers, to understand their mutual interaction, as well as their possible role in canine and human mammary tumorigenesis. In order to confirm the impacts of the communication role of the exosomes with the extracellular medium and other cells, co-culture of the exosomes isolated from the patients' serum will be performed against the HB4a / MCF-10A mammary non-tumor epithelial lines. The results of this study will ultimately promote the model of liquid biopsy with a panel of biomarkers that will allow the early, sensitive and specific diagnosis of primary and metastatic breast cancer. (AU)