ACVR2B and thalassemia: The HSP70 mRNA was up-regulated in both α- and β-thalassemia erythroid cells (Figure 3c), while no significant differences in the levels of TGF-β receptor, ACTRIIA, ACTRIIB, GDF11, and FOXO3 transcripts were revealed between thalassemia and normal cells (Supplemental Figure S1).