Juglone induces ferroptotic effect on hepatocellular carcinoma and pan-cancer via the FOSL1-HMOX1 axis

Abstract

Background

Drug therapy plays an essential role in the management of hepatocellular carcinoma (HCC). Recently, the use of natural products to suppress tumor cells has emerged as a promising direction for drug development. Juglone, a natural compound, exhibits anticancer activities across various cancer types. However, the precise mechanism underlying the anticancer effect of juglone, especially in HCC, remains elusive.

Purpose

This study aimed to investigate the potential inhibitory effects of juglone on HCC and pan-cancer, as well as elucidate the underlying mechanism.

Methods

Cell Counting Kit-8 and colony formation assays were used to examine cell proliferation. Transwell and wound healing assays were used to evaluate cell migration. Cell cycle distribution was assessed by flow cytometry. The in vivo effect of juglone on HCC was evaluated by establishing the HCC xenograft mice model. RNA sequencing and inhibitors targeting diverse modes of programmed cell death were applied to uncover the form of juglone-induced cell death. Integrated transcriptomic, and proteomic analyses unveiled the underlying mechanism. The dual-luciferase reporter assay was employed to verify the findings. The pan-cancer value of juglone was assessed using TCGA database analysis and cellular assays.

Results

Juglone suppressed HCC growth via ferroptosis in vitro and in vivo, which is evidenced by increased levels of iron, lipid peroxidation (LPO), reactive oxygen species (ROS), malondialdehyde (MDA), and decreased levels of glutathione (GSH). Omic analyses, gene silencing and functional analyses showed the upregulated HMOX1 and FOSL1 were the key effector molecule and transcriptional factor in juglone-induced ferroptosis, respectively. The binding site of FOSL1 at the promoter of HMOX1 was identified. Juglone could induce ferroptosis in pan-cancer by activating the FOSL1-HMOX1 axis.

Conclusion

Our findings, for the first time, demonstrate that juglone effectively inhibits tumor growth by inducing FOSL1-HMOX1-dependent ferroptosis, thereby offering a promising strategy for the development of anticancer drugs.