Tenofovir disoproxil fumarate induces fetal hemoglobin production in K562 cells and β-YAC transgenic mice: A therapeutic approach for γ-globin induction

Pharmacologic induction of fetal hemoglobin (HbF) is an effective strategy for treating beta-hemoglobinopathies like beta-thalassemia and sickle cell anemia by ameliorating disease severity. Hydroxyurea is the only FDA-approved agent that induces HbF, but significant nonresponders and toxicity limit its clinical usefulness. This study relates preclinical investigation of Tenofovir disoproxil fumarate (TDF) as a potential HbF inducing agent, using human erythroleukemia cell line and a beta-YAC mouse model. Erythroid induction of K562 cells was studied by the benzidine/H2O2 reaction, total hemoglobin production was estimated by plasma hemoglobin assay kit, and gamma-globin gene expression by RT-qPCR, whereas, fetal hemoglobin production was estimated by flow cytometry and immunofluorescence microscopy. We observed significantly increased gamma- globin gene transcription and HbF expression mediated by TDF in K562 cells. Subsequent treatment of beta-YAC transgenic mice with TDF confirmed HbF induction in vivo through an increase in gamma-globin gene expression and in the percentage of HbF positive red blood cells. Moreover, TDF showed no cytotoxic effect at HbF inducing concentrations. These data support the potential development of TDF for the treatment of hematological disorders, including beta-thalassemia and sickle cell anemia.