IREB2 and neoplasm: Interestingly, increases in intracellular iron have been observed in many different tumour types (Torti & Torti, 2013), and we wondered if there might be a connection between STAG2 loss-of-function and iron dysregulation given the potential STAG2/IREB2 genetic interaction in HAP1 and H4 cells, the two transformed cell line contexts (Fig 1F).