Detecção de uma subpopulação de vesículas extracelulares em amostras de soro de pacientes com câncer de mama

Abstract

Breast cancer (BC) is the most common neoplasm among women and one of the leading causes of female mortality worldwide. Among detection and screening strategies, mammography stands out; however, diagnosis must be confirmed by needle biopsy. In this context, less invasive and sensitive methods capable of identifying molecular alterations have been increasingly explored, with special attention given to liquid biopsy, in which body fluids, especially blood, are collected and analyzed for tumor characterization. Within this framework, the present study aimed to identify, in the serum of BC patients, a CD63-positive exosome subpopulation using a peptide previously selected by Phage Display, and to correlate absorbance values with patients’ clinical data. To this end, Magneto-ELISA assays using tosylated particles were performed, considering as parameters the diagnosis (BC versus benign breast disease), Ki-67 levels, expression of hormonal and growth receptors, molecular subtype, pathological staging, and histological grade. The absorbance values were compared using the Mann–Whitney t test, with a statistically significant difference observed in the discrimination of Nottingham grade 1 versus grade 3 tumors (p = 0.0056). A ROC curve was then constructed, with an area under the curve of 0.97 (p = 0.0087), demonstrating the high potential of Magneto-ELISA to discriminate patients between grades 1 and 3. Thus, these findings highlight the importance of studying and utilizing liquid biopsy in the characterization of oncology patients.