Synergistic enhancement of anticancer effects by periodontal ligament stem cell exosomes and oxaliplatin via apoptosis induction and protein modulation

Periodontal ligament stem cell-derived exosomes (PDLSC-exosomes) exhibit promising therapeutic potential in cancer treatment. Here, we characterize PDLSC-exosomes and investigate their effects on colorectal (HT-29, HCT-116) and oral (SCC-25) cancer cell lines. Nanoparticle tracking analysis and transmission electron microscopy revealed exosome diameters ranging from 80-220 nm and typical cup-shaped morphology. Flow cytometry confirmed surface markers CD9, CD63, and CD81. PKH67-labeling demonstrated efficient exosome internalization by all three cell lines. PDLSC-exosomes significantly inhibited cancer cell growth and colony formation in a dose-dependent manner. Synergistic effects were observed when combined with oxaliplatin, enhancing growth inhibition, apoptosis induction, and motility reduction. Apoptotic assays revealed increased Bax and p53 gene expression and altered protein profiles, particularly those involved in apoptosis and immune signaling pathways. Proteomic analysis identified differentially expressed proteins linked to translational processes and vesicle fusion. This study highlights the synergistic effects of PDLSC-exosomes and oxaliplatin, providing novel insights into their potential as an adjunct therapy to enhance cancer cell sensitivity and apoptosis.