4 research outputs found
Tuberous Sclerosis Complex cellâderived EVs have an altered protein cargo capable of regulating their microenvironment and have potential as disease biomarkers
Abstract Hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) is a feature of many solid tumours and is a key pathogenic driver in the inherited condition Tuberous Sclerosis Complex (TSC). Modulation of the tumour microenvironment by extracellular vesicles (EVs) is known to facilitate the development of various cancers. The role of EVs in modulating the tumour microenvironment and their impact on the development of TSC tumours, however, remains unclear. This study, therefore, focuses on the poorly defined contribution of EVs to tumour growth in TSC. We characterised EVs secreted from TSC2âdeficient and TSC2âexpressing cells and identified a distinct protein cargo in TSC2âdeficient EVs, containing an enrichment of proteins thought to be involved in tumourâsupporting signalling pathways. We show EVs from TSC2âdeficient cells promote cell viability, proliferation and growth factor secretion from recipient fibroblasts within the tumour microenvironment. Rapalogs (mTORC1 inhibitors) are the current therapy for TSC tumours. Here, we demonstrate a previously unknown intercellular therapeutic effect of rapamycin in altering EV cargo and reducing capacity to promote cell proliferation in the tumour microenvironment. Furthermore, EV cargo proteins have the potential for clinical applications as TSC biomarkers, and we reveal three EVâassociated proteins that are elevated in plasma from TSC patients compared to healthy donor plasma