Abstract 3661: Extracellular vesicle derived from neural stem cells as potential vehicles of genetic information to modulate glioblastoma biology
Authors: de Araújo João Pedro Alves , Cruz Lilian , Souza Maria Clara da Silva , Prado Mariana Brandão , Alves Rodrigo Nunes , Coelho Bárbara Paranhos , Soares Samuel Ribeiro , Fernandes Camila Félix , Lopes Marilene Hohmuth 
Published: April 2023

Abstract
Glioblastoma (GBM) is a deadly brain tumor and its high aggressiveness is partly due to a subpopulation of tumor stem cells known as glioblastoma stem-like cells (GSCs). GBM establishes crosstalk with non-tumoral cells, mediated mainly by extracellular vesicles (EVs) and the interaction between GSCs and neural stem cells (NSCs) from the subventricular zone may influence GBM biology. Literature data suggests that cellular communication is an important process for GSCs stemness maintenance, and some authors consider NSCs as a possible cell of origin for GSCs. However, the specific effects that neural stem cells-derived extracellular vesicles (NSCs-EVs) promote in GSCs are still uncertain. Previous data from our group demonstrated specific groups of microRNAs (hsa-miR -137, -216a-5p, -216b-5p, 217), enriched in NSCs-EVs in contrast to intracellular compartments, suggesting these molecules are being produced for secretion. Our study aims to evaluate the role of the miRs contained in NSCs-EVs in GSCs biology. Human induced pluripotent stem cells (hiPSC) were differentiated into NSCs. NSCs were characterized by western blotting and immunofluorescence by the expression of neural commitment markers, such as nestin and β-III-tubulin. NSCs-EVs were isolated from NSCs’ culture media with a commercial kit and analyzed by NTA (nanosight) for EVs size profiling and western blotting to detect specific markers, such as Alix, CD63, and HSP90. In a first approach, we analyzed the effects played by those miRs through predictive online tools. We identified target genes related to stemness (NANOG, SOX2, KLF4), oncogenesis (KRAS, CDC42, CDK6) and metabolism (CAMK2A), besides the Wnt and Notch signaling pathways. The online predictions also identified transcriptional factors related to vasculogenesis and self-renewal, key processes for GSCs activity. We will expose GSCs to NSCs-EVs and evaluate the expression of neural and stemness markers. In a future step, the GSCs previously exposed to NSCs-EVs will be treated with temozolomide, and viability assays will be performed. Additionally, we intend to modulate the four miRs identified and evaluate if they act as effector molecules of NSCs-EVs. Our data corroborate with our initial hypothesis that NSCs-EVs may act as important signalling modes in GSCs activity and consequently in GBM biology. Supported by FAPESP:22/08106-1.
Citation Format: João Pedro Alves de Araújo, Lilian Cruz, Maria Clara da Silva Souza, Mariana Brandão Prado, Rodrigo Nunes Alves, Bárbara Paranhos Coelho, Samuel Ribeiro Soares, Camila Félix Fernandes, Marilene Hohmuth Lopes. Extracellular vesicle derived from neural stem cells as potential vehicles of genetic information to modulate glioblastoma biology. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3661.