Apoptosis has long been recognized as a significant mechanism for inhibiting
tumor formation, and a plethora of stimuli can induce apoptosis during the progression and treatment of
tumors. Moreover,
tumor-derived apoptotic extracellular vesicles (apoEVs) are inevitably phagocytosed by live
tumor cells, promoting
tumor heterogeneity. Understanding the mechanism by which apoEVs regulate
tumor cells is imperative for enhancing our knowledge of
tumor metastasis and recurrence. Herein, we conducted a series of in vivo and in vitro experiments, and we report that
tumor-derived apoEVs promoted
lung adenocarcinoma (LUAD)
metastasis, self-renewal and chemoresistance. Mechanistically, we demonstrated that apoEVs facilitated
tumor metastasis and stemness by initiating the epithelial-mesenchymal transition program and upregulating the transcription of the
stem cell factor SOX2. In addition, we found that ALDH1A1, which was transported by apoEVs, activated the NF-κB signaling pathway by increasing
aldehyde dehydrogenase enzyme activity in recipient
tumor cells. Furthermore, targeting apoEVs-ALDH1A1 significantly abrogated these effects. Collectively, our findings elucidate a novel mechanism of apoEV-dependent intercellular communication between apoptotic
tumor cells and live
tumor cells that promotes the formation of cancer stem cell-like populations, and these findings reveal that apoEVs-ALDH1A1 may be a potential therapeutic target and
biomarker for LUAD
metastasis and recurrence.