Activation of ICAM-1 promoter by lysophosphatidylcholine: Possible involvement of protein tyrosine kinases

Lysophosphatidylcholine (lyse-PC) selectively upregulates the mRNA level of intercellular adhesion molecule-1 (ICAM-1) but not that of vascular cell adhesion molecule-1 (VCAM-1) in cultured human umbilical vein endothelial cells. Transfection studies show that lyse-PC activates the ICAM-1 promoter but not the VCAM-1 promoter. Gel mobility shift assays document an increase in NF-kappa B binding in cells treated with lyse-PC. The increases of ICAM-1 mRNA and NF-kappa B binding were inhibited by the protein tyrosine kinase inhibitors, genistein and lavendustin A, but not by inhibitors for cyclic AMP-dependent protein kinases or protein kinase C. Our results suggest that lyse-PC induces ICAM-1 expression most likely by activating NF-kappa B, and that the effect appears to be protein tyrosine kinase-dependent.