Abstract 1852: Uncovering regulatory mechanisms and therapeutic targets in EV-mediated nanoparticle transfer: A proteomics and high-throughput screening approach

Abstract Extracellular vesicles (EVs) are naturally occurring vesicles that facilitate the transfer of biomolecules between cells, playing a vital role in cellular communication and regulation. Recently, EVs have been discovered participating active transport of nanomaterials between cells, suggesting a novel method to enhance the delivery of nanoparticles. A 3D intercellular exchange assay has been developed by our group to monitor and quantify EV-mediated transfer of silver nanoparticles (AgNPs) across different cell types. Furthermore, distinct EV subpopulations, those containing AgNPs (AgNP-containing) and those without (AgNP-free), were isolated from AgNP-exposed cells using density gradient ultracentrifugation. In this study, we leverage proteomics and high-throughput screening (HTS) to reveal the regulatory mechanisms of EV-mediated intercellular communication and identify compounds that regulate this process. Using mass spectrometry and advanced bioinformatics, unique protein signatures associated with each EV type were identified, uncovering biomarkers that indicate origin and functional relevance in EV-mediated transport process. To investigate potential regulators of EV-mediated intercellular exchange, we combined HTS with our 3D intercellular exchange assay to identify compounds that modulate EV-mediated transfer of nanomaterials. Integrating HTS with quantitative proteomics enabled us to identify key compounds that specifically impact the formation and secretion of AgNP-free and AgNP-containing EV subpopulations. These findings not only provide new insights into the regulatory mechanisms controlling nanomaterial-sorting and EV genesis but also highlight potential therapeutic targets for modulating EV-mediated intercellular exchange, which may further improve nanomedicine delivery. This work underscores the utility of combining proteomics and HTS for the discovery of small molecules capable of regulating EV-mediated transfer, with implications for therapeutic development and biomarker discovery. Citation Format: Xian Wu, Hong-Bo Pang. Uncovering regulatory mechanisms and therapeutic targets in EV-mediated nanoparticle transfer: A proteomics and high-throughput screening approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1852.