GPX4 and melanoma: 6-MF targets PTBP1 to inhibit circPIAS1 biogenesis and reduce circPIAS1-108aa.6-MF inhibits PI3K-AKT pathway; combined with IFN-γ, it enhances STAT1 phosphorylation, inhibits SLC7A11/GPX4 pathway, promoting melanoma ferroptosis.