Abstract
Hepatocellular carcinoma (HCC) is the fifth most common malignancies with limited curative options and poor prognosis. Gentian violet (GV) has recently been found to have anti-tumor properties with promising clinical applications. However, its anti-tumor effect and the underlying functional mechanisms in HCC have not been investigated. In this study, we found that GV induced ferroptosis and apoptosis, inhibited cell proliferation, migration and invasion in a dose-dependent manner in vitro, and significantly attenuated the growth of HCC in vivo. Both ferroptosis inhibitor Ferrostain-1 (Fer-1) and apoptosis inhibitor Z-VAD-KFM (Z-VAD) partially attenuated GV-induced growth-inhibitory effects, while combined treatment of Fer-1 and Z-VAD completely abolished GV's activities. Increased levels of intracellular reactive oxygen species (ROS) were detected after GV treatment. Interestingly, GV elevated the expression levels of both p53 and its negative regulator MDM2, which was dependent on the expression of the dehydrogenase/reductase protein Hep27. Simultaneously silencing both the MDM2 and p53 genes by siRNAs abolished ROS production and partially rescued the cell death induced by GV treatment. Our data demonstrate a GV-Hep27-MDM2-p53 signaling cascade that regulates ferroptosis and apoptosis. Furthermore, our findings provide insights into understanding the anti-tumor function of GV and present the basis of new therapeutic strategies for the treatment of HCC.