ACSL3 and cancer: Magtanong et al. (2019) found that acyl-CoA synthetase long-chain family member 3 (ACSL3) converts monounsaturated fatty acids (MUFAs) into its acyl-CoA ester for incorporation into membrane phospholipids, thereby protecting cancer cells from ferroptosis. However, the levels of fatty acids (include MUFAs and PUFAs) in human serum are much higher than those in classical media containing fetal bovine serum (FBS), so how cells maintain the level of free fatty acid pools in cells is important to determine whether cells experience ferroptosis (Kamphorst et al., 2013; Magtanong et al., 2019).