Circulating exosomes characterization as predictors of treatment response in breast cancer

• Grant number: 18/17133-7
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2018
• Effective date (End): November 30, 2019
• Field of knowledge: Biological Sciences - Genetics - Human and Medical Genetics
• Principal researcher: Márcia Maria Chiquitelli Marques Silveira
• Grantee: Mariana Regatieri Polezi
• Home Institution: Hospital do Câncer de Barretos. Fundação Pio XII (FP). Barretos , SP, Brazil

Abstract

Breast neoplasms are the main cause of mortality by cancer in women. Metastasis is the cause of about 90% of the deaths in patients with malignant neoplasm, in such way that the process of invasion and metastasis play an important role in cancer dissemination. In this context, in the intercommunication between the cells and the microenvironment is a crucial step. The exosomes have been emerged as potential mediators of this cell-to-cell communication, once they can transfer information they carry, such as proteins, lipids and nucleic acids to other cell in the body. The role of exosomes in the beginning and cancer progression is particularly interesting for oncologists since the neoplastic cells secrete 10 times more exosomes than normal cells and, so, they are facilitators of cellular communication through the transport of growth factors, cytokines, microRNAs and other molecules. The exosomes are protected by a bilipidic layer witch allows them to carry genetic information (RNA and proteins) to distant sites of the body, and, thus, they can induce the formation of metastatic niche facilitating cancer dissemination. Considering that several studies point to the presence of exosomes in circulating witch levels are associated with tumor development, this project is within the line of breast cancer biomarkes and refers to an exosome characterization the potential biomarkers of cancer recurrence and progression. In the present study, the concentration and size of plasma vesicles of patients with breast cancer (stages I, II and III) will be measured, comparing two groups, the group with recurrence of the disease (breast cancer) and the group without recurrence. Our hypothesis is that patients with breast cancer have serum levels of exosomes associated with the metastatic phenotype and tumor recurrence, whose circulating levels of these markers can be used as indicative of the worst prognosis. The results of this project will be useful for a better understanding of the molecular genetic bases of the breast cancer metastasis process and the role of the exosomes in this process.