BackgroundSeveral cytokines and adhesion molecules released from endothelium play an important role in inflammation, immune responses, and probably atherogenesis.ObjectiveTo determine whether the transcription factor nuclear factor-κB mediated expression of these genes involved in the inflammatory response of endothelial cells to tumor necrosis factor-α, by using transcription factor decoy oligodeoxynucleotides.Design and methodsWe first transfected fluorescein isothiocyanate (FITC)-labeled double-stranded oligodeoxynucleotides into endothelial cells by a cationic liposome-mediated method of gene transfer. We then confirmed that the decoy oligodeoxynucleotides could block binding of nuclear factor-κB to its specific cis element effectively. In addition, we transfected the reporter gene chloramphenicol acetyltransferase driven by three repeated nuclear factor-κB binding sequences in the promoter and enhancer region.ResultsFITC-labeled oligodeoxynucleotides were detected in the nuclei of approximately 70% of the total cells. Tumor necrosis factor—stimulated expression of chloramphenicol acetyltransferase was partially inhibited by transfection of nuclear factor-κB decoy oligodeoxynucleotides, but not by transfection of scrambled oligodeoxynucleotides. Also nuclear factor-κB decoy oligodeoxynucleotides but not scrambled oligodeoxynucleotides inhibited tumor necrosis factorinduced expression of interleukin-6 and intracellular adhesion molecule-1 both at the messenger RNA and at protein level (assessed by reverse transcription—polymerase chain reaction and enzyme-linked immunosorbent assay).ConclusionOur results demonstrate that nuclear factor-κB decoy oligodeoxynucleotides transfected by cationic liposome method inhibited tumor necrosis factor —induced expression of interleukin-6 and intracellular adhesion molecule-1 in endothelial cells.