Induction of CCAAT/enhancer binding protein-delta by cytokinins, but not by retinoic acid, during granulocytic differentiation of human myeloid leukaemia cells.
Cytokinins, purine derivatives that act as hormones to control many processes in plants, are very effective at inducing the granulocytic differentiation of human myeloid leukaemia cells. Isopentenyladenine (IPA), a potent cytokinin, significantly induced the expression of CCAAT/enhancer-binding protein (C/EBP)delta, but not C/EBP alpha protein, whereas all-trans retinoic acid, a well-known inducer of granulocytic differentiation, induced C/EBP alpha but not C/EBP delta protein. Antisense oligonucleotide for C/EBP delta, but not C/EBP alpha or C/EBP beta, effectively suppressed IPA-induced differentiation, suggesting that the expression of C/EBP delta protein is necessary for cytokinin-induced differentiation. Although C/EBP alpha is known to be crucial for granulocytic differentiation, the function of C/EBP delta has not been well documented in the regulation of haematopoiesis. The role of C/EBP delta in the granulocytic differentiation of myeloid leukaemia cells is discussed.
Ishii
Yuki
Y
Division of Cancer Treatment, Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Saitama, Japan.
Kasukabe
Takashi
T
Honma
Yoshio
Y
D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D051743:CCAAT-Enhancer-Binding Protein-delta; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism* / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D003583:Cytokinins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D006098:Granulocytes / Q000378:metabolism* / Q000473:pathology; D018922:HL-60 Cells; D006801:Humans; D007541:Isopentenyladenosine; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D014157:Transcription Factors / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D022762:CCAAT-Enhancer-Binding Proteins; C497252:CEBPD protein, human; D003583:Cytokinins; D016376:Oligonucleotides, Antisense; D014157:Transcription Factors; D051743:CCAAT-Enhancer-Binding Protein-delta; C001478:N(6)-(delta(2)-isopentenyl)adenine; D014212:Tretinoin; D007541:Isopentenyladenosine; D000225:Adenine