Glycosphingolipids of various human ovarian tumors: a significantly high expression of I3SO3GalCer and Lewis antigen in mucinous cystadenocarcinoma.

Among several human ovarian tumors, which include mucinous cystadenocarcinoma, serous cystadenocarcinoma, and clear cell adenocarcinoma, the mucinous cystadenocarcinoma showed a unique glycosphingolipid composition. In particular, more than 90% of the acidic glycosphingolipids in the mucinous cystadenocarcinoma is comprised of sulfolipids, which are hardly detected in normal ovary and are contained in concentrations of less than 40% in the other type of ovarian tumors. By means of negative ion fast atom bombardment mass spectrometry and gas liquid chromatography, the major sulfolipid in mucinous cystadenocarcinoma is confirmed to be I3SO3-GalCer with N-cerebronoyl phytosphingosine, that which contrasts with I3SO3-GalCer with N-nonhydroxy fatty acyl sphingosine as the major molecular species in the other ovarian cancers. In mucinous cystadenocarcinoma, galactosylceramide is found in the relatively high concentration and is also composed of N-cerebronoyl phytosphingosine. In addition, the concentrations of glycolipids with Le(a) and Le(b) antigenicities are significantly higher in mucinous cystadenocarcinoma than those in normal ovary and the other ovarian tumors.