Differential effect on U937 cell differentiation by targeting transcriptional factors implicated in tissue- or stage-specific induced integrin expression.
The inhibition of transcription factor functions was used to define their role in phorbol ester-induced cellular differentiation of a monocytic cell line, U937. We demonstrate a differential effect on cell adhesion and differentiation: antisense or competitive binding with double-stranded oligonucleotides antagonized the functions of AP-1, NF-kappaB, and PU.1 transcriptional factors. In the presence of phorbol 12-myristate 13-acetate (PMA), U937 cells attached to the plastic surface and cells were characterized by marked expression of beta2-integrin molecules on the cell surface. We show that the in vivo differentiation of U937 cells appears to occur normally in the absence of AP-1 activity. In contrast, the addition to the cell culture of phosphorothioate oligonucleotides that contained the NF-kappaB or PU.1 binding sites significantly inhibited U937 differentiation. The absence of NF-kappaB led to pleiotropic effects with a clear reduction in the expression of integrin and other lineage-specific myeloid antigens on the cell surface. In contrast, the absence of PU.1 had a more restricted effect on integrin expresion on the cell surface, probably as a result of blockage of CD18 gene expression.
Departamento de Análisis Clínicos, Hospital Universitario Virgen de las Nieves, Universidad de Granada, Spain.
A
A
García
A
A
Serrano
E
E
Abril
P
P
Jimenez
L M
LM
Real
J
J
Cantón
F
F
Garrido
F
F
Ruiz-Cabello
D018821:CD18 Antigens / Q000096:biosynthesis*; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D016328:NF-kappa B / Q000502:physiology*; D016376:Oligonucleotides, Antisense; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000502:physiology*; D018808:Transcription Factor AP-1 / Q000502:physiology*; D020298:U937 Cells; D000099232:Proto-Oncogene Protein Spi-1
D018821:CD18 Antigens; D016328:NF-kappa B; D016376:Oligonucleotides, Antisense; D011518:Proto-Oncogene Proteins; D013755:Tetradecanoylphorbol Acetate; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D000099232:Proto-Oncogene Protein Spi-1