GSE132836
A variant erythroferrone disrupts iron homeostasis in SF3B1-mutated myelodysplastic syndrome (RNA-Seq)
Myelodysplastic syndromes (MDS) with ring sideroblasts are hematopoietic stem celldisorders with erythroid dysplasia and mutations in the SF3B1 splicing factor gene. MDS patientswith SF3B1 mutations often accumulate excessive tissue iron, even in the absence oftransfusions, but the mechanisms that are responsible for their parenchymal iron overload areunknown. Body iron content, tissue distribution, and the supply of iron for erythropoiesis arecontrolled by the hormone hepcidin, which is regulated by erythroblasts through secretion of theerythroid hormone erythroferrone (ERFE). Here, we identified an alternative ERFE transcript inMDS patients with the SF3B1 mutation. Induction of this ERFE transcript in primary SF3B1-mutated bone marrow erythroblasts generated a variant protein that maintained the capacity tosuppress hepcidin transcription. Plasma concentrations of ERFE were higher in MDS patientswith a SF3B1 gene mutation than in patients with SF3B1 wild-type MDS. Thus, hepcidinsuppression by a variant erythroferrone is likely responsible for the increased iron loading inpatients with SF3B1-mutated MDS, suggesting that ERFE could be targeted to prevent ironmediated toxicity. The expression of the variant ERFE transcript that was restricted to SF3B1-mutated erythroblasts decreased in lenalidomide-responsive anemic patients, identifying variantERFE as a specific biomarker of clonal erythropoiesis. Overall design: RNAseq analysis of healthy controls (n=5) and MDS patients (n=27) divided into wildtype and mutated SF3B1 patients.