ABSTRACT: Background: Gastric cancer (GC) is an aggressive malignancy characterized by metabolic reprogramming, including dysregulated cholesterol biosynthesis. Medicarpin (Med), a natural isoflavan isolated from Radix Hedysari, has shown pharmacological potential; however, its anti-GC activity and metabolic mechanisms remain unclear. Methods: The effects of Med on cell viability, proliferation, colony formation, and migration were evaluated in AGS and HGC-27 GC cells. Its antitumor efficacy and preliminary tolerability were assessed in nude-mouse xenograft models. Untargeted metabolomics and quantitative proteomics were integrated to identify Med-associated metabolic alterations and targets. Western blotting, cholesterol measurement, Filipin staining, and exogenous cholesterol rescue assays were performed to validate the mechanism. Results: Med significantly inhibited the viability, proliferation, clonogenicity, and migration of AGS and HGC-27 cells in a concentration- and time-dependent manner, while showing minimal cytotoxicity in normal gastric mucosal GES-1 cells. In xenograft models, Med reduced tumor volume and weight without body-weight loss or histopathological injury to major organs. Multi-omics analyses revealed extensive metabolic remodeling, with marked suppression of lipid, steroid, and primary bile acid biosynthesis. Proteomic analysis and Western blotting showed that Med downregulated the key mevalonate pathway enzymes MVK, HMGCS1, and LSS, thereby reducing intracellular cholesterol levels. Exogenous cholesterol supplementation substantially reversed Med-induced inhibition of GC cell viability, proliferation, and colony formation. Conclusion: Med suppresses GC progression by downregulating MVK, HMGCS1, and LSS, thereby inhibiting mevalonate pathway-mediated cholesterol biosynthesis. These findings support Med as a promising natural candidate for targeting lipid metabolic reprogramming in GC.
