NFS1 and lung adenocarcinoma: Evidently, intracellular cyst(e)ine contribute to ferroptosis suppression via at least two additional pathways in different contexts: in a mouse lung adenocarcinoma model, NFS1 cysteine desulfurase utilizes cysteine to synthesize iron–sulfur clusters, which are necessary for preventing activation of the iron-starvation response, subsequent iron influx and ferroptosis14 (Fig. 1).