Tumor-derived extracellular vesicles-mediated oxidative stress transfer activates glycometabolic reprogramming of CAFs.

BACKGROUND: In the adverse tumor microenvironment excessive tumor cell proliferation is accompanied by massive reactive oxygen species (ROS) production. Though tumor-derived extracellular vesicles (TEVs) have confirmed roles in cancer-associated fibroblast (CAF) interactions, the intercellular ROS transfer mechanism and its specific role in tumor-stroma communication remain unclear. METHOD: Human gingival fibroblasts (HGFs), paracancerous normal fibroblasts (PNFs) and CAFs were isolated from volunteers' healthy gingival tissues and 6 OSCC patients. In vitro, autophagy and glycometabolism levels in PNFs/CAFs and HGFs/TEVs-treated HGFs were assessed via immunofluorescence and Western blot; autophagy was blocked or activated to explore its effect on glycometabolism; flow cytometry was used to detect if TEVs trigger fibroblast autophagy and glycolysis via ROS transfer. In vivo, xenograft models were established to validate TEVs' effect. RESULTS: CAFs had higher autophagy than PNFs. Autophagy inhibitors reduced TEVs-induced autophagy-dependent glycometabolic reprogramming, while autophagy activation enhanced CAF glycolysis. Moreover, TEV-transferred ROS drove such reprogramming via autophagy-dependent mechanisms and the HIF-1α/PFKFB3 axis. In vivo, TEVs consistently promoted autophagy and glycometabolic reprogramming. CONCLUSION: TEVs-induced intercellular ROS transmission and the regulatory role of autophagy in CAF glycometabolic reprogramming offer a novel basis for the oxidative stress transfer model in tumor-stroma crosstalk.