title: Cyclic nucleotide response element binding (CREB) protein activation is involved in K562 erythroleukemia cells differentiation.
abstract: K562 are human erythroleukemia cells inducible to differentiate into megakaryocytic or erythroid lineage by different agents. Cyclic nucleotide Response Element Binding (CREB) protein, a nuclear transcription factor which mediates c-AMP signaling, is a potential candidate involved in the occurrence of erythroid differentiation and adaptive response. Here we investigated signaling events in K562 cells induced with 30 microM hemin to undergo erythroid differentiation. CREB activation was detected early 1 h after hemin treatment and up to 4 and 6 days of treatment, when K562 terminal differentiation occurs together with caspase-3 maximal activation and PARP degradation. It was interesting to note that after hemin treatment in the presence of SB203580, p38 MAP kinase specific inhibitor, a reduced rate of CREB phosphorylation as well as a lower percentage of CD71/Gly+ (Glycophorin A) cells were detectable, demonstrating the p38 MAP kinase dependency of these phenomena. All in all these results document a novel relationship between CREB activation and differentiation-related apoptotic cell death and assign a role to p38 MAP kinase pathway in determining these events in K562 erythroleukemia cells.
authors.affiliation: Dipartimento di Biomorfologia, Chieti-Pescara, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Di Pietro
authors.forename: Viviana
authors.initials: V
authors.lastname: di Giacomo
authors.forename: Luciana
authors.initials: L
authors.lastname: Caravatta
authors.forename: Silvia
authors.initials: S
authors.lastname: Sancilio
authors.forename: Rosa Alba
authors.initials: RA
authors.lastname: Rana
authors.forename: Amelia
authors.initials: A
authors.lastname: Cataldi
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D006427:Hemin / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D020014:K562 Cells; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism / Q000473:pathology; D008856:Microscopy, Fluorescence; D010766:Phosphorylation / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D012694:Serine / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D007093:Imidazoles; D011725:Pyridines; D012694:Serine; D006427:Hemin; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580