Isolation and characterization of exosomes during induction of endoplasmic reticulum stress in glioblastoma cell lines

• Grant number: 16/24507-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2017
• End date: November 30, 2018
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: José César Rosa
• Grantee: Sabrina de Fátima Comin
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Stressful stimuli trigger in most cell lines stress-reducing and cell-survival mechanisms such as Unfolded Protein Response (UPR). This type of cellular stress response causes an increase in vesicle secretion by RE and Golgi apparatus, which when are secreted by these cells are named exosomes. In the body fluids, such as blood, urine, saliva and liquor, these microvesicles contain mRNAs, microRNAs, non-coding RNAs, cytoplasmic and membrane proteins, as receptors and molecules of the MHC complex. Several biomolecules are candidates for disease biomarkers. Recent studies indicate that intercellular communication by exosomes can modulate target cell gene expression, as well as growth, cell division and differentiation processes, stress response, cell survival and apoptosis. However, these properties have been shown to be present also in tumor cells, where secretion of exosomes by tumor cells influences tumor progression and the development of metastases. Due to their properties and presence in body fluids, where they can be collected, exosomes are becoming promising candidates for new biomarkers for the early diagnosis and prognosis of numerous diseases, including cancer. In this way, we will treat cell lines of glioblastoma, U87MG and T98G, with cellular stress inducing drugs that have different mechanisms of action, such as thapsigargin, tunicamycin and temozolamide, and to evaluate the release of exosomes characterizing the proteomic profile of these vesicles by means of " Shotgun proteomics " using liquid chromatography coupled to mass spectrometry. (AU)