Glabridin from <i>Glycyrrhiza glabra</i> L. Exhibits Anti-Triple-Negative Breast Cancer Effects by Regulating Various Cell Cycle Genes

Glabridin (GLA), a characteristic polyphenolic extracted from the renowned sweet plant<i>Glycyrrhiza glabra</i> L., demonstrates potent anticancer effects. This study aims to investigate the effects of GLA on triple-negative breast cancer (TNBC) and its underlying mechanisms. The IC₅₀ values of GLA in MDA-MB-231 and MDA-MB-468 cells were calculated as 62.48 ± 2.62 and 64.77 ± 1.86 μM, respectively. <i>In vivo</i> experimental results confirmed that GLA (10 and 30 mg/kg) induced no hepatorenal toxicity in mice but significantly suppressed TNBC growth (<i>P</i> < 0.05). Through multiomics integration, chemometric analysis, and random forest algorithm, five key genes (<i>MCM8</i>, <i>MCM3</i>, <i>CDC6</i>, <i>EXO1</i>, and <i>ATAD2</i>) involved in cell cycle pathways and two key metabolites (<i>N</i>,<i>N</i>-dimethylarginine and Kuwanon K) were identified. Microarray data and molecular biology experiments demonstrated that GLA significantly downregulated these key genes, thereby inhibiting the cell cycle progression in TNBC. Notably, CDC6 was identified as a target protein of GLA using a drug affinity responsive target stability and cellular thermal shift assay. Molecular docking results revealed that, compared to norcantharidin, GLA exhibited distinct binding energy (-7.6 vs -6.4 kcal/mol) and a different binding mode with CDC6, supporting its potential as a novel CDC6 inhibitor. These findings provide valuable insights into the potential therapeutic application of GLA for TNBC treatment.