Tumor cells as the origin of elevated serum alpha 1,3fucosyltransferase inassociation with malignancy

We have previously reported that the elevated activities of serum alpha1,3f ucosyltransferase reverted to normal levels after curative removal of the t umors. To determine the origin of elevated serum alpha1,3fucosyltransferase , blood samples were obtained from both the drainage vein and the artery in patients with different stages of colorectal cancer at surgery. The enzyme levels in all samples from the drainage vein were found to be higher than the levels in the artery that fed the tumor. Hence, the origin of elevated alpha1,3fucosyltransferase in serum was thought to be the tumor rather than the liver that is the normal source of serum alpha1,3fucosyltransferase. W hen serum samples not only from colorectal cancer patients but also from pa tients with gastric, liver, lung, pancreas, bladder and esophagus cancer we re treated with anti-FUTVI antibody, the measured activities of alpha1,3fuc osyltransferase were markedly reduced. Further, secretion of alpha1,3fucosy ltransferase from human colorectal carcinoma cells was also detected in the culture medium by Western immuno-blot analysis with anti-FUTVI antibody.