Chemokine stromal cell-derived factor-1 induction by C/EBP activation is associated with all-trans-retinoic acid-induced leukemic cell differentiation

Authors:
Kim K, Kim HH, Kim JH, Choi YH, Kim YH, Cheong J
In:
Source: J Leukoc Biol
Publication Date: (2007)
Issue: 82(5): 1332-9
Research Area:
Immunotherapy / Hematology
Cells used in publication:
U-937
Species: human
Tissue Origin: blood
Platform:
Nucleofector® I/II/2b
Abstract
Stromal cell-derived factor-1 (SDF-1/CXCL12) is one of the essential chemokines, which mediates hematopoietic differentiations. However, the mechanism by which SDF-1 expression is regulated in granulocyte differentiation is poorly understood. Here, we suggest a novel mechanism by which all-trans-retinoic acid (ATRA) induces the expression of SDF-1 during the differentiation of promyelomonocytic leukemic U937 cells. Moreover, we also demonstrate that activation of transcription factor C/EBPbeta by ATRA regulates SDF-1 expression in U937 cells. In addition, we show that the cyclin-dependent kinase inhibitors p21(WAF1/CIP1) and Pyk2 are up-regulated by SDF-1 and increased markedly by the costimulation of ATRA and SDF-1. Furthermore, ATRA and SDF-1alpha additively induce U937 cell differentiation. Indeed, silencing the expression of SDF-1 inhibits ATRA-induced granulocyte differentiation significantly. Taken together, these results indicate that SDF-1alpha is involved in granulocyte differentiation in response to ATRA, mediated by the activation of the transcription factor C/EBPbeta.