Andrographolide Suppresses Head and Neck Squamous Cell Carcinoma Progression via EGR1-ACSL4 Axis-Mediated Ferroptosis

Head and neck squamous cell carcinoma (HNSCC) is a highly aggressive malignancy with high rates of recurrence and metastasis that result in poor clinical outcomes. Ferroptosis, an iron-dependent, lipid peroxidation-driven regulated cell death pathway, offers a therapeutic strategy to enhance antitumor effects by exploiting cancer cell vulnerability to iron-mediated lipid peroxidation. Andrographolide (ADE), the major bioactive component extracted from Andrographis paniculata, demonstrates extensive antitumor activities. However, its specific role and mechanisms in HNSCC are unclear. The in vitro effects of ADE on HNSCC were evaluated using comprehensive experimental approaches which included CCK8, clonogenic survival analysis, wound healing, transwell migration, western blotting, omics analysis, and ferroptosis assessment. Its in vivo antitumor effects were confirmed using C57BL/6J mouse and patient-derived xenograft models. The results showed that ADE suppresses HNSCC growth by inducing ferroptosis. Mechanistically, ADE transcriptionally upregulates acyl-CoA synthetase long-chain family member 4 (ACSL4) by increasing the nuclear accumulation of early growth response 1 (EGR1) to thereby trigger ferroptosis. Furthermore, in vivo studies corroborated the finding that ADE attenuates tumor progression through ACSL4-dependent ferroptosis. In conclusion, our study reveals that ADE induces ferroptosis in HNSCC via the EGR1-ACSL4 axis. This finding highlights the potential of ADE as a therapeutic agent, and provides a mechanistic foundation for its future clinical applications in HNSCC.