TNF and rheumatoid arthritis: Besides its well-established role in lipid peroxidation during ferroptosis, ALOX15 has pro-inflammatory properties and was shown to be highly expressed in synovial RA membranes (Gheorghe et al. 2009). It was demonstrated that an ALOX15 metabolite upregulated the TNF-α expression in vascular cells and macrophages (Bolick et al. 2005; Dwarakanath et al. 2008).