The Role of MicroRNAs Carried by Extracellular Vesicles in Tumorigenesis Through Reprogramming the Mitochondrial...

Mitochondrial dysfunction is not merely a byproduct of transformation but a driver of tumorigenesis, metastasis, and therapeutic resistance. Recent advancements in intercellular communication have identified Extracellular Vesicles (EVs) or exosomes as critical mediators that bridge the gap between the tumor and its microenvironment (TME). These EVs contain a complex repertoire of bioactive cargo, including proteins, lipids, and RNAs. Among the class of RNAs, small non-coding RNAs, microRNAs (miRNAs), are the most abundantly expressed bioactive compounds that are selectively packaged and delivered to recipient cells. EV-delivered miRNAs can target nuclear-encoded mitochondrial genes and have also been reported to localize to mitochondria (mitomiRs), where they function as post-transcriptional regulators of bioenergetic and mitochondrial dynamic adaptations that support tumor progression. This review explores the "EV-miRNA-Mitochondria Axis", delineating the molecular mechanisms by which EV-carried miRNAs reprogram the "Mitochondrial Information Processing System" (MIPS) - a signaling network where mitochondria integrate metabolic cues (e.g., ROS, calcium flux) to dictate critical biological outcomes, such as immune regulation and cell survival. We summarized specific sorting machineries (e.g., hnRNPA2B1, Lupus La) that package oncogenic miRNAs into EVs and how these cargoes hijack mitochondrial function upon delivery. Specifically, we discussed how EV-miRNAs induce metabolic shifts, manipulate mitochondrial dynamics (fission/fusion), and inhibit the intrinsic apoptosis to drive cancer progression. Finally, we highlighted the dual utility of these EV-miRNAs as drivers of pathogenesis and promising non-invasive biomarkers for early diagnosis, prognostic and therapeutic monitoring.