INCREASED MESSENGER-RNA EXPRESSION OF A NOVEL PROSTACYCLIN-STIMULATING FACTOR IN HUMAN COLON-CANCER

We recently cloned a prostacyclin (PGl(2))-stimulating factor (PSF), w hich stimulates PGl(2) production by cultured vascular endothelial cel ls. Immunohistochemistry and Northern blot analysis demonstrated that PSF was highly expressed in colon cancer sites compared with normal co lon mucosa obtained from the same patient, as well as in cultured aden ocarcinoma cell lines compared with cultured normal colon mucosal cell lines. Increased levels of the PSF protein were detected in the cultu re media of these adenocarcinoma cells compared with levels in the cul ture media of normal mucosal cells. These results suggest that PSF is closely associated with carcinogenesis of colon mucosa.