Bacillus Calmette-Guérin immunotherapy-induced extracellular vesicles promote antitumor immunity in bladder cancer

Background: Intravesical Bacillus Calmette-Guérin (BCG) immunotherapy remains one of the most effective treatments for non-muscle invasive bladder cancer (NMIBC). However, a substantial proportion of patients fail to respond, and the precise mechanisms underlying BCG's therapeutic effects remain incompletely understood. While extracellular vesicles (EVs) can modulate a range of biological processes, their relevance in this context is also poorly understood. Methods: . Results: significantly potentiated the therapeutic efficacy of BCG in a syngeneic murine bladder cancer model. Conclusion: as critical intermediaries in the anti-tumor immune response and suggest their potential utility as mediators and/or predictive biomarkers for therapeutic efficacy. In summary, we propose a previously unrecognized mechanism of BCG immunotherapy mediated by EVs, establishing them as pivotal components of the immune signaling network driving effective treatment outcomes.