Ginsenoside compound K inhibits migration and invasion of melanoma cells by regulating EMT via the IL-6/STAT3 signaling pathway.

The present study aims to investigate the inhibitory effects of ginsenoside compound K (GCK) on malignant melanoma (MM) metastasis and systematically elucidate the underlying molecular mechanisms. Herein, GCK inhibited proliferation, migration, and invasion while promoting apoptosis in MM cells as determined by cell counting kit-8 (CCK-8) assay, Annexin V-FITC/PI apoptosis detection kit, wound-healing, and transwell assay, respectively. Network pharmacology and molecular docking were utilized to identify candidate targets and signaling pathways, which were further confirmed by western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). To validate the mechanistic involvement of the IL-6/STAT3 signaling pathway, rescue experiments were performed using IL-6-overexpressing A375 cells, and the in vivo antitumor efficacy of GCK was evaluated in a B16F10 melanoma xenograft model in C57BL/6J mice. In vitro cytotoxicity assays demonstrated that GCK exerted potent cytotoxic effects against A375 cells, with an IC50 value of 23.60 ± 2.50 µg/mL. Notably, GCK treatment significantly increased the apoptotic rate of A375 cells, while markedly suppressing their migratory and invasive capacity. Western blot analysis further revealed that GCK suppresses MM metastasis by reversing the epithelial-mesenchymal transition (EMT) phenotype and attenuating the activities of matrix metalloproteinase (MMP)-2 and MMP-9. Consistent with the findings of network pharmacology and molecular docking analyses, STAT3, IL-6, PTGS2, IL-1β, TNF, NF-κB1 and TLR4 were identified as top hub genes. Furthermore, western blotting and qRT-PCR confirmed that GCK inhibited melanoma cell metastasis through reversing the EMT process and downregulating the expression of MMP-2 and MMP-9, which was mediated by the IL-6/STAT3 signaling pathway. Importantly, rescue experiments demonstrated that IL-6 overexpression significantly enhanced A375 cell invasion, and this pro-invasive effect was markedly reversed by GCK treatment, confirming the IL-6/STAT3 axis as a critical functional mediator of GCK's anti-metastatic activity. In vivo, GCK administration significantly inhibited B16F10 tumor growth in a dose-dependent manner with a favorable safety profile, and western blot analysis of tumor lysates revealed dose-dependent downregulation of TLR4, IL-6, and p-STAT3, while total STAT3 levels remained unchanged. Our study highlights that GCK may serve as a promising agent for the further MM therapy.