Regulation of phospholipase D activity and ceramide production in daunorubicin-induced apoptosis in A-431 cells.
We demonstrated here that daunorubicin induced apoptosis in A-431 cells, a human epidermoid carcinoma cell line. Treatment of cells with daunorubicin induced chromatin condensation, nuclear fragmentation, internucleosomal DNA degradation, and the proteolytic cleavage of PKC-delta and poly(ADP-ribose) polymerase in A-431 cells. Daunorubicin, as well as sphingomyelinase (SMase) and the exogenous cell-permeable ceramide analogue C(2)-ceramide, inhibited phospholipase D activity stimulated by phorbol 12-myristate 13-acetate or epidermal growth factor (EGF). Like ceramide, daunorubicin also decreased EGF-induced diacylglycerol generation. However, no increase in ceramide level was observed in daunorubicin-induced apoptosis in A-431 cells. Moreover, treatment of A-431 cells with exogenous cell-permeable C(2)-ceramide or SMase did not induce apoptosis. These results indicate that daunorubicin induces apoptosis in A-431 cells via a mechanism that does not involve increased ceramide formation.
Chen
J S
JS
State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Box 25, 320 Yue-Yang Road, 200031, Shanghai, PR China.
Chai
M Q
MQ
Chen
H H
HH
Zhao
S
S
Song
J G
JG
D017209:Apoptosis; D002518:Ceramides / Q000096:biosynthesis*; D003630:Daunorubicin / Q000494:pharmacology*; D004075:Diglycerides / Q000096:biosynthesis; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D010739:Phospholipase D / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013108:Sphingomyelin Phosphodiesterase / Q000494:pharmacology; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D002518:Ceramides; D004075:Diglycerides; C064769:N-acetylsphingosine; D013108:Sphingomyelin Phosphodiesterase; D010739:Phospholipase D; D013110:Sphingosine; D003630:Daunorubicin