Abstract
Many complex processes are involved in metastasis. Of these, the most important step might be that of the tumor cell passing through tissue barrier such as endothelial cells and basement membrane. Cell adhesion molecules, selectins, which are specifically recognize tumor-associated antigens, namely sialyl Lex and sialyl Lea, are thought to be closely involved in this step. The expression of sialyl dimeric Lex and LTA receptors in primary lesions has been found to influence the metastatic potential and prognosis of transitional cell carcinoma of the human bladder. We suggest that the interaction of these carbohydrate epitopes on a 60kD glycoprotein with selectins promotes metastasis.