Licoricidin triggers reactive oxygen species-mediated PANoptosis in human hepatocellular carcinoma cells.
Licoricidin (LCD), a natural isoflavonoid compound extracted from Glycyrrhiza species, has been extensively demonstrated to possess diverse biological activities, including anti-inflammatory and potent anti-cancer effects. However, the precise mechanism underlying LCD action against hepatocellular carcinoma (HCC) remains unclear, particularly regarding its regulation of cell death. In this study, we comprehensively explored the effects of LCD on HCC cells in vitro and investigated its role and mechanism of action in the induction of PANoptosis. Our results reveal that LCD exhibited potent anti-HCC activities by decreasing cell viability and significantly inhibiting clonogenic survival in HCC cell lines. Our results demonstrate that LCD triggered a substantial accumulation of reactive oxygen species and induced depolarization of the mitochondrial membrane, leading to profound mitochondrial dysfunction. We further confirmed that LCD activated a comprehensive PANoptosis program by synchronously upregulating the expression of apoptotic proteins (Bax, c-CASP3, and c-PARP1), pyroptotic proteins (c-CASP 1 and c-GSDMD), and the phosphorylation of necroptotic executioners (p-MLKL and p-RIPK1). Treatment with the ROS inhibitor (NAC), apoptosis inhibitor (ZVAD), or necroptosis inhibitor (Nec-1) significantly reduced the expression of PANoptosis-related proteins in LCD-treated cells. Furthermore, molecular docking simulations and cellular thermal shift assay (CETSA) assay confirmed the direct and stable binding of LCD to PANoptosis-related proteins. In summary, we show for the first time that LCD exerts favorable anti-HCC activities via the induction of PANoptosis through a ROS-dependent mechanism and potntial direct modulation of core executive proteins. This multi-target action suggests that LCD could be a novel candidate for the management of hepatocellular carcinoma.