An Anti-cancer Drug, Paclitaxel. Induces Apoptosis in MCF-7 Human Breast Cancer Cells by Generating Ceramide and Arachidonic Acid

Accumulation of ceramide mass in MCF-7 cells by the anti-cancer agent. paclitaxel. was found to occur primarily due to activation of the de novo synthesis pathway. Morever. the addition of paclitaxel resulted in the accumulation of ceramide, which was followed by a prolonged arachidonic acid release. Participation of ceramide de novo pathway in arachidonate signaling was detected since L-cycloserine, an inhibitor of de novo synthesis, was able to inhibit the paclitaxel-induced AA release and cytotoxicity. (omitted)