Elucidation of Selective Apoptosis of Breast Cancer Cells Induced by Panax ginseng –Derived Exosomes via Regulation of Bax/Bcl‐2 Ratio and AMPK‐ α Signaling

This study evaluated the anticancer potential of Panax ginseng –derived exosomes (PGEs) against MDA‐MB‐231 breast cancer cells, focusing on AMP‐activated protein kinase (AMPK)–mediated apoptosis and tumor cell selectivity. PGE was isolated using size‐exclusion chromatography and exhibited a mean particle size of 163.4 nm with a concentration of 1.2 × 10 ¹⁰ particles/mL. The exosomal identity was verified by elevated expression levels of CD9 (91.4%), CD63 (96.8%), and TET‐8 (127.2%). Treatment with PGE caused a dose‐dependent decline in the viability of MDA‐MB‐231 cells (87.2% at 0.38 × 10 ¹⁰ particles/mL), while normal human mammary epithelial cells (HMECs) maintained 90.1% viability even at 3.0 × 10 ¹⁰ particles/mL, indicating selective induction of apoptosis. In scratch assays, PGE suppressed MDA‐MB‐231 migration by up to 29.8% but enhanced HMEC proliferation and migration by 88.5%, demonstrating selective anti‐invasive effects. Molecular analysis showed increased expression of AMPK‐ α , Bax, caspase‐3, and caspase‐9, coupled with downregulation of Bcl‐2 and vascular endothelial growth factor, thereby validating mitochondrial apoptosis as the underlying mechanism. Flow cytometry further revealed a dose‐dependent increase in early and late apoptosis in MDA‐MB‐231 cells (total apoptosis: 17.7%–32.9%), while HMEC displayed only minimal apoptotic response (< 7.6%). Immunofluorescence analysis also indicated chromatin condensation, ZO‐1 disruption, and F‐actin reorganization in MDA‐MB‐231, whereas HMEC preserved structural integrity with enhanced ZO‐1 and F‐actin intensity. LC‐MS/MS profiling identified ginsenosides Rf, Rh1, and Rb1 as principal bioactive constituents of PGE, implicating them in AMPK‐dependent apoptosis. Taken together, these results demonstrated that PGE selectively triggers apoptosis in breast cancer cells while maintaining normal cell viability, highlighting its potential as a natural exosome‐based anticancer therapeutic with strong biocompatibility and translational potential.