Chemical induction of ferroptosis through GPX4 inhibition: Rational design of triazole-benzoxazine hybrids for melanoma therapy

Melanoma, a highly metastatic cancer with rising incidence, faces therapeutic challenges due to drug resistance and recurrence. In this study, we designed novel 1,2,3-triazole-benzoxazinone hybrids via pharmacophore hybridization to address these limitations. Lead compounds 3e and 4d demonstrated potent anti-melanoma activity, with IC50 values of 5.26 μM (3e) and 9.42 μM (4d) in A375 cells, and 8.9 μM (3e) and 3.63 μM (4d) in SK28 cells, respectively. Mechanistically, they induced ferroptosis, a first-in-class mechanism for this scaffold, by downregulating SLC7A11, and GPX4, triggering ROS accumulation and lipid peroxidation—effects reversed by ferroptosis inhibitor Fer-1. Molecular docking confirmed direct binding to GPX4's active site via π-π stacking and hydrogen bonds, promoting its proteasomal degradation. Structural optimization enhanced selectivity: derivatives showed negligible toxicity in normal cells and murine models, achieving a 3-5-fold higher therapeutic index than conventional agents. This study pioneers a dual-functional scaffold hybridization strategy, merging synthetic innovation with ferroptosis induction to overcome resistance. The robust efficacy, mechanistic clarity, and superior safety profile of 3e and 4d position them as transformative candidates for metastatic melanoma therapy, offering a novel approach to combat drug resistance and toxicity barriers.