New role for granulocyte colony-stimulating factor-induced extracellular signal-regulated kinase 1/2 in histone modification and retinoic acid receptor alpha recruitment to gene promoters: relevance to acute promyelocytic leukemia cell differentiation.
Fiche publication
Date publication
avril 2011
Auteurs
Membres identifiés du Cancéropôle Est :
Dr ROCHETTE-EGLY Cécile, Dr DESPOUY Gilles
Tous les auteurs :
Cassinat B, Zassadowski F, Ferry C, Llopis L, Bruck N, Lainey E, Duong V, Cras A, Despouy G, Chourbagi O, Beinse G, Fenaux P, Rochette Egly C, Chomienne C
Lien Pubmed
Résumé
The induction of the granulocytic differentiation of leukemic cells by all-trans retinoic acid (RA) has been a major breakthrough in terms of survival for acute promyelocytic leukemia (APL) patients. Here we highlight the synergism and the underlying novel mechanism between RA and the granulocyte colony-stimulating factor (G-CSF) to restore differentiation of RA-refractory APL blasts. First, we show that in RA-refractory APL cells (UF-1 cell line), PML-RA receptor alpha (RARalpha) is not released from target promoters in response to RA, resulting in the maintenance of chromatin repression. Consequently, RARalpha cannot be recruited, and the RA target genes are not activated. We then deciphered how the combination of G-CSF and RA successfully restored the activation of RA target genes to levels achieved in RA-sensitive APL cells. We demonstrate that G-CSF restores RARalpha recruitment to target gene promoters through the activation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway and the subsequent derepression of chromatin. Thus, combinatorial activation of cytokines and RARs potentiates transcriptional activity through epigenetic modifications induced by specific signaling pathways.
Référence
Mol Cell Biol. 2011 Apr;31(7):1409-18