Objective To investigate the potential molecular mechanisms of glycyrrhizin in the treatment of oral squamous cell carcinoma (OSCC) by integrating network pharmacology, molecular docking, and in vitro experiments.

Methods Glycyrrhizin targets were obtained from PubChem, SwissTargetPrediction, and TargetNet databases. OSCC-associated genes were retrieved from GeneCards and OMIM databases, and overlapping targets were identified as candidate therapeutic targets. A protein-protein interaction network was constructed using the STRING database and Cytoscape software to screen hub targets. Gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using ClueGO. Survival analysis was conducted based on the TISIDB database to identify prognosis-related key genes. Molecular docking validation was performed using AutoDock Vina. In vitro experiments were carried out in HSC-3 cells to validate the anti-tumor activity of glycyrrhizin and its regulatory effects on signaling pathways.

Results A total of 37 common targets of glycyrrhizin and OSCC were identified. Protein-protein interaction network analysis identified STAT3, JUN, MMP9, AR, BCL2L1, IL2, PSEN1, MMP2, CYP2D6, and TLR9 as hub targets. Functional enrichment analysis revealed that candidate targets were mainly enriched in biological processes, including vascular smooth muscle cell proliferation, Notch signaling regulation, and immune response modulation, as well as signaling pathways such as the Notch signaling pathway and neuroactive ligand-receptor interaction. Survival analysis demonstrated that patients with high expression of PSEN1 and TLR9 had significantly shorter median survival times compared with low-expression groups (PSEN1: 1.8 vs. 3.2 years, P=0.004 62; TLR9: 2.1 vs. 4.5 years, P=0.000 483), suggesting that high expression of both genes was significantly associated with poor prognosis in patients. Molecular docking revealed favorable binding affinity between glycyrrhizin and both PSEN1 and TLR9. In vitro experiments confirmed that glycyrrhizin inhibited HSC-3 cell proliferation and downregulated the expression of key proteins in the Notch signaling pathway.

Conclusion This study preliminarily elucidates the potential molecular mechanism of glycyrrhizin in intervening in OSCC from multiple perspectives. Its anti-tumor effects may be associated with the regulation of the Notch signaling pathway and immune-related processes, providing a theoretical basis for further mechanism exploration and translational research.

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