Decitabine increases fetal hemoglobin in Papio anubis by increasing γ-globin gene transcription.
OBJECTIVE
The mechanism responsible for increased fetal hemoglobin levels following decitabine treatment remains controversial. These experiments were performed to evaluate the role of transcriptional vs. translational mechanisms in the ability of decitabine to increase fetal hemoglobin levels in vivo.


METHODS
Three normal, nonanemic baboons were treated with decitabine subcutaneously (0.5 mg/kg/d) for 10 days. The effect of decitabine on globin chain synthesis and globin messenger RNA levels was measured in pre- and posttreatment bone marrow aspirates by biosynthetic radiolabeling with [(3)H] leucine followed by separation of globin chains by high-performance liquid chromatography, and real-time polymerase chain reaction, respectively. The effect on DNA methylation of the ɛ- and γ-globin gene promoters was determined by bisulfite sequence analysis.


RESULTS
Decitabine treatment of normal, nonanemic baboons induced similar increases in the γ/γ+β chain synthetic ratio and the γ/total β-like globin RNA ratio and also increased expression of ɛ-globin transcripts. Increased expression of ɛ- and γ-globin was associated with decreased DNA methylation of the ɛ- and γ-globin gene promoters.


CONCLUSIONS
Decitabine increases fetal hemoglobin in vivo by transcriptional activation of the γ-globin gene.
Akpan
Imo
I
Department of Medicine, University of Illinois at Chicago, and Jesse Brown VA Medical Center, Chicago, IL 60612, USA.
Banzon
Virryan
V
Ibanez
Vinzon
V
Vaitkus
Kestis
K
DeSimone
Joseph
J
Lavelle
Donald
D
D000818:Animals; D001374:Azacitidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D019175:DNA Methylation / Q000187:drug effects; D000077209:Decitabine; D005319:Fetal Hemoglobin / Q000235:genetics* / Q000378:metabolism; D010215:Papio; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D055544:beta-Globins / Q000235:genetics / Q000378:metabolism; D055547:epsilon-Globins / Q000235:genetics / Q000378:metabolism; D055545:gamma-Globins / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D055544:beta-Globins; D055547:epsilon-Globins; D055545:gamma-Globins; D000077209:Decitabine; D005319:Fetal Hemoglobin; D001374:Azacitidine