FECH and cancer: Iron transportation to FECH is suggested to be facilitated within the mitochondria by dynamic protein complexes of haem synthesis enzymes, FECH, protoporphyrinogen IX oxidase and 5-ALA synthase 2,50 alongside iron transporters, ABCB10 and mitoferrin-1.51 Perturbations in these complexes, low iron availability or impaired uptake into the mitochondria could all be contributing factors to the reduced activity of FECH and the accumulation of PpIX seen in cancers.