ECH1 encodes a delta(3,5)-delta(2,4)-dienoyl-CoA isomerase that catalyzes the isomerization of unsaturated fatty acids during mitochondrial beta-oxidation, a crucial step in the metabolism of polyunsaturated fatty acids (PUFAs). The protein localizes to both mitochondrial and peroxisomal compartments and contains targeting signals for both organelles. ECH1 functions in lipid metabolism regulation with emerging roles in ferroptosis suppression. In glioblastoma, ECH1 undergoes K63-linked ubiquitination by TRAF3, which impedes its mitochondrial translocation and thereby limits PUFA oxidation and promotes lipid peroxidation 1. In metastatic ovarian cancer, high PUFA-lipid states create dependencies on ECH1 alongside other beta-oxidation enzymes, with ECH1 inhibition combined with ACSL4 suppression achieving potent metastasis reduction 2. ECH1 overexpression alleviates nonalcoholic steatohepatitis in mice by suppressing ferroptosis through Erk signaling modulation 3. In aortic valve disease, ECH1 suppresses Wnt5a/calcium signaling to prevent Runx2-driven calcification in ApoE-/- mice on a high-cholesterol diet 4. A circular RNA derived from ECH1 regulates bronchopulmonary dysplasia through a miR-708-5p/Ntrk2 axis 5. These findings position ECH1 as a potential therapeutic target in metabolic disease, ferroptosis-related pathologies, and certain cancers, though clinical drug candidates specifically targeting ECH1 have not yet been reported.