Cytosolic 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid binding sites in carcinoma cells

12(S)-HETE stimulates gene and cell surface expression of the integrin GPIIb/IIIa in carcinoma cells. The cells have high affinity binding sites for 12(S)-HETE. Analyses of the subcellular distribution and size of these sites showed that cytosol was the predominant location and that the apparent molecular weight was close to 670,000. Besides cytosol, mitochondria, nuclei, and plasma membranes also contained 12(S)-HETE binding sites. The mainly cytosolic location of the binding sites is different from that of other eicosanoid receptors which are G-protein coupled plasma membrane proteins of the rhodopsin gene family.