Itraconazole inhibits nuclear delivery of extracellular vesicle cargo by disrupting the entry of late endosomes into the nucleoplasmic reticulum

Extracellular vesicles (EVs) are mediators of intercellular communication under bothhealthy and pathological conditions, including the induction of pro-metastatic traits,but it is not yet known how and where functional cargoes of EVs are delivered to theirtargets in host cell compartments. We have described that after endocytosis, EVsreach Rab+late endosomes and a fraction of these enter the nucleoplasmic reticu-lum and transport EV biomaterials to the host cell nucleoplasm. Their entry thereinand docking to outer nuclear membrane occur through a tripartite complex formedby the proteins VAP-A, ORP and Rab (VOR complex). Here, we report that theantifungal compound itraconazole (ICZ), but not its main metabolite hydroxy-ICZor ketoconazole, disrupts the binding of Rab to ORP–VAP-A complexes, leadingto inhibition of EV-mediated pro-metastatic morphological changes including cellmigration behaviour of colon cancer cells. With novel, smaller chemical drugs, inhi-bition of the VOR complex was maintained, although the ICZ moieties responsiblefor antifungal activity and interference with intracellular cholesterol distributionwere removed. Knowing that cancer cells hijack their microenvironment and thatEVs derived from them determine the pre-metastatic niche, small-sized inhibitors ofnuclear transfer of EV cargo into host cells could nd cancer therapeutic applications,particularly in combination with direct targeting of cancer cells