ACSL4 and polyunsaturated lipids support metastatic extravasation and colonization.

Metastatic dissemination to distant organs demands that cancer cells possess high morphological and metabolic adaptability. However, contributions of the cellular lipidome to metastasis remain elusive. Here, we uncover a correlation between metastasis potential and ferroptosis susceptibility in multiple cancers. Metastases-derived cancer cells exhibited higher ferroptosis sensitivity and polyunsaturated fatty acyl (PUFA)-lipid contents than primary-tumor-derived cells from ovarian cancer patients. Metabolism-focused CRISPR screens in a mouse model for ovarian cancer distant metastasis established via two rounds of in vivo selection revealed the PUFA-lipid biosynthesis enzyme acyl-coenzyme A (CoA) synthetase long-chain family member 4 (ACSL4) as a pro-hematogenous metastasis factor. ACSL4 promotes metastatic extravasation by enhancing membrane fluidity and cellular invasiveness. While promoting metastasis, the high PUFA-lipid state creates dependencies on abhydrolase-domain-containing 6, acylglycerol lipase (ABHD6), enoyl-CoA delta isomerase 1 (ECI1), and enoyl-CoA hydratase 1 (ECH1)-rate-limiting enzymes preparing unsaturated fatty acids (UFAs) for β-oxidation. ACSL4/ECH1 co-inhibition achieved potent suppression of metastasis. Our work establishes the dual functions of PUFA-lipids in tumor progression and metastasis that may be exploitable for therapeutic development.