[Cancer-associated alterations of glycoconjugates--special reference to glycosphingolipids].

Glycoconjugates show the dramatic alterations of the carbohydrate structures in association with oncogenic transformation of the cells. Since glycoconjugates on the cell surfaces are involved in the cellular recognition and response, the structural changes of the carbohydrate in the cancer cells seemed to be closely related to the cell-cell adhesion, cell growth, cell behavior and metastatic property. One of the characteristic changes of glycosphingolipids in association with the oncogenic transformation is oncofetal change, and the other is the molecular mimicry of the glycosphingolipids to those in the cells of immune system. These phenomena indicate how the cancer cells smartly escape the immune surveillance system of the host. In this chapter, cancer-associated changes of glycosphingolipids together with glycolipid synthetase are summarized, and also our recent work on glycosphingolipids in metastatic tumor cells is introduced.