Huaier counteracts sorafenib resistance in hepatocellular carcinoma by activating NCOA4-mediated ferritinophagy to induce ferroptosis via modulation of iron and lipid metabolism

Resistance to molecular-targeted agents, represented by sorafenib (SOR), poses a major challenge in the treatment of hepatocellular carcinoma (HCC). Huaier (HUA), a traditional Chinese medicine used as an Adjuvant cancer therapy, has demonstrated favorable efficacy in clinical practice for advanced HCC. This study demonstrates that HUA reverses SOR resistance in HCC and exhibits synergistic effects with SOR by modulating NCOA4-mediated ferritinophagy, thereby influencing iron and lipid metabolic pathways associated with ferroptotic vulnerability. In SOR-resistant Huh7^R cells and mouse xenograft models, HUA alone or combined with SOR disrupted iron homeostasis through ferritinophagy induction, promoted Fe³⁺ reduction to Fe²⁺, enhanced ROS generation, induced lipid peroxidation, and concurrently reduced lipid droplet storage and triglyceride accumulation. Mechanistically, HUA upregulated NCOA4 and increased the LC3B-II/I ratio, leading to FTH1 degradation. Accumulated Fe²⁺ drove robust ROS production via the Fenton reaction, exacerbated lipid peroxidation, upregulated ACSL4, and downregulated SCD1 and GPX4, collectively inducing Ferroptosis, a form of regulated cell death specifically rescued by ferrostatin-1 or deferoxamine but not by Z-VAD-FMK or necrostatin-1, with minimal Caspase activation. Furthermore, this cascade markedly downregulated PLIN2, resulting in energy depletion in Huh7^R cells and tumor tissues, thereby impairing adaptive survival and ultimately reversing SOR resistance. Notably, NCOA4 silencing substantially attenuated HUA's efficacy in overcoming SOR resistance. These findings highlight the role of HUA in promoting NCOA4-dependent ferritinophagy and modulating iron and lipid metabolism to enhance ferroptotic sensitivity, providing a rationale for the clinical development of HUA + SOR combination therapy in HCC.