Erastin is primarily used in biomedical research for its ability to induce ferroptosis, a form of regulated cell death driven by iron-dependent lipid peroxidation. It serves as a tool compound to study the mechanisms and pathways involved in ferroptosis, which has implications in cancer, neurodegenerative diseases, and ischemia-reperfusion injury. In oncology research, erastin demonstrates selective toxicity toward certain cancer cells, especially those with mutations in the RAS pathway or resistance to apoptosis, making it valuable for exploring alternative cancer therapies. It is also used to probe the function of system Xc⁻, a cystine/glutamate antiporter, as erastin inhibits this transporter, leading to depletion of glutathione and subsequent oxidative damage. Due to its role in disrupting redox balance, erastin helps researchers investigate cellular antioxidant defenses and the role of glutathione peroxidase 4 (GPX4) in cell survival. Its application remains largely confined to laboratory settings, aiding in the development of ferroptosis-targeting drugs and the understanding of oxidative stress-related pathologies.