Effects of 5-aza-2'-deoxycytidine on fetal hemoglobin levels, red cell adhesion, and hematopoietic differentiation in patients with sickle cell disease.
Fetal hemoglobin (HbF) decreases polymerization of sickle hemoglobin (HbS) and improves outcomes in sickle cell disease (SSD). Therefore, a therapeutic goal in SSD is pharmacologic reactivation of HbF. Silencing of the gamma-globin (HbF) gene is associated with DNA methylation. The cytosine analog 5-aza-2'-deoxycytidine (decitabine) hypomethylates DNA by inhibiting DNA methyltransferase. We examined if subcutaneous decitabine could increase HbF levels and improve SSD pathophysiology without cytotoxicity. Eight symptomatic SSD patients resistant or intolerant of standard treatment with hydroxyurea received decitabine 0.2 mg/kg subcutaneously 1 to 3 times per week in 2 cycles of 6-week duration. Treatment decreased neutrophils and increased mean HbF (6.5% to 20.4%, P <.0001) and mean total hemoglobin (76 to 96 g/L [7.6 to 9.6 g/dL], P <.001). Features of vaso-occlusive crisis pathophysiology such as red cell adhesion, endothelial damage, and coagulation pathway activity significantly improved. gamma-Globin gene promoter methylation decreased, and platelets and the proportion of megakaryocytes and erythroid cells in the marrow increased without a decrease in marrow cellularity, consistent with a DNA hypomethylating, noncytotoxic mechanism of action. Weekly subcutaneous decitabine produces cumulative increases in HbF and total hemoglobin through a noncytotoxic mechanism of action. Chronic dosing and sustained increases in hemoglobin F and total hemoglobin levels may be possible. Further studies in SSD and thalassemia are indicated.
Saunthararajah
Yogen
Y
University of Illinois at Chicago, Section of Hem/Onc, MBRB Rm 3150 (MC734), 900 S Ashland Ave, Chicago, IL 60607, USA. yogen@uic.edu
Hillery
Cheryl A
CA
Lavelle
Don
D
Molokie
Robert
R
Dorn
Louise
L
Bressler
Linda
L
Gavazova
Stefana
S
Chen
Yi-Hsiang
YH
Hoffman
Ronald
R
DeSimone
Joseph
J
D000328:Adult; D000755:Anemia, Sickle Cell / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D001374:Azacitidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*; D015415:Biomarkers / Q000032:analysis; D001777:Blood Coagulation / Q000187:drug effects; D001853:Bone Marrow / Q000473:pathology; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D019175:DNA Methylation / Q000187:drug effects; D000077209:Decitabine; D004730:Endothelium, Vascular / Q000473:pathology; D004912:Erythrocytes / Q000187:drug effects* / Q000473:pathology; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis* / Q000187:drug effects; D006410:Hematopoiesis / Q000187:drug effects*; D006801:Humans; D007249:Inflammation; D007797:Laminin / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019699:Thrombospondins / Q000378:metabolism; D014652:Vascular Diseases / Q000209:etiology / Q000517:prevention & control
D015415:Biomarkers; D007797:Laminin; D019699:Thrombospondins; D000077209:Decitabine; D005319:Fetal Hemoglobin; D001374:Azacitidine