beta-1,4-galactosyltransferase (beta-1,4-GT) has been reported to be activated in ovarian carcinoma cells and an isoform of this enzyme has been used as a tumor marker for ovarian cancer. The present study was undertaken to clarify how beta-1,4-GT affected the cell biological characteristics of ovarian cancer. To this end, we transfected an ovarian tumor cell line with an antisense gene of beta-1,4-GT. Proliferative potential and morphology of the cells transfected with the antisense gene did not differ from those of the control cells. Adhesive potential to the constituents of extracellular matrix was reduced in the antisense gene transfectants. In a nude mouse, the number of peritoneal dissemination foci of the antisense transfectants was smaller than that of the control cells. These results indicated that beta-1,4-GT is closely related to the invasive and metastatic potentials of ovarian cancer while it is not involved in the proliferative potential.