ANTIPROLIFERATIVE ACTIVITY OF CERAMIDES ISOLATED FROM NORMAL HUMAN OVARY AND OVARIAN TUMOR

Ceramides modulate cell growth, differentiation and apoptosis. We have previously demonstrated that human epithelial ovarian tumors contain dihydroceramides that are absent from normal ovary. Dihydroceramides d iffer in their biological effects from ceramides; therefore antiprolif erative activity of ceramides isolated from normal human ovary and ova rian tumors was studied. Ceramides (3 mu M) of normal ovary are more p otent inhibitors of [H-3]thymidine incorporation into human ovarian ca rcinoma cells (CaOv) than ceramides of ovarian tumors. Effects of vari ous pools of tumor ceramides were similar regardless of significant di fferences in the contents of sphingenine and sphinganine. It is sugges ted that antiproliferative activity of ceramides depends not only on t he sphingoid base structure but also on the fatty acid structure.