Primary
liver cancer is the third leading cause of
cancer death in the world, and the lack of effective treatments is the main reason for the high mortality.
Corosolic acid (CA) has been proved to have antitumor activity. In this study, we found that CA can sensitize
liver cancer cells to ferroptosis, which is a regulated form of cell death characterized by
iron-dependent
lipid peroxides reaching lethal levels. Here, we revealed that CA can inhibit
glutathione (GSH) synthesis via HERPUD1, decreasing the cellular GSH level and causing
liver cancer cells to become more sensitive to ferroptosis. Mechanistically, further studies found that HERPUD1 reduced the ubiquitination of the GSS-associated
E3 ubiquitin ligase MDM2, which promoted ubiquitination of GSS, thereby inhibiting GSH synthesis to increase ferroptosis susceptibility. Importantly, a mouse xenograft model also demonstrated that CA inhibits
tumor growth via HERPUD1. Collectively, our findings suggesting that CA is a candidate component for the development of treatments against
liver cancer.