Requirement of AP-1 for Ceramide-induced Apoptosis in Human Leukemia HL-60 Cells

doi:10.1074/jbc.270.45.27326

Requirement of AP-1 for Ceramide-induced Apoptosis in Human Leukemia HL-60 Cells (*)

From the (1) First Division, Department of Internal Medicine, Faculty of Medicine, Kyoto University, Kyoto 606, the Departments of
(2) Medicine and
(3) Oral Surgery, Osaka Dental University, Osaka 540, and the
(4) Division of Transfusion, Shimane Medical College, Shimane 693, Japan

^§ To whom correspondence should be addressed:
Dept. of Medicine, Osaka Dental University, 1-5-17 Otemae, Cyuo-ku, Osaka, Japan 540.
Tel.: 81-6-943-6521; Fax: 81-6-943-8051.

Abstract

Ceramide has emerged as a novel lipid mediator in cell proliferation, differentiation, and apoptosis. In this work, we demonstrate that the levels of c-jun mRNA, c-Jun protein, and DNA binding activity of a nuclear transcription factor AP-1 to 12-o-tetradecanoylphorbol 13-acetate responsive elements all increased following treatment with the cell-permeable ceramide, N-acetylsphingosine in human leukemia HL-60 cells. N-Acetylsphingosine (1-10 μM) increased the levels of c-jun mRNA in a dose-dependent manner, and maximal expression was achieved 1 h after treatment. Increase of c-jun expression treated with 5 μMN-acetyldihydrosphingosine, which could not induce apoptosis, was one third of that with 5 μMN-acetylsphingosine. Ceramide-induced growth inhibition and DNA fragmentation were both prevented by treatment with curcumin, 1,7-bis[4-hydroxy-3-methoxy-phenyl]-1,6-heptadiene-3,5-dione (an inhibitor of AP-1 activation), or antisense oligonucleotides for c-jun. These results suggest that the transcription factor AP-1 is critical for apoptosis in HL-60 cells and that an intracellular sphingolipid mediator, ceramide, modulates a signal transduction inducing apoptosis through AP-1 activation.

Footnotes

↵* This work was supported by Grants 06267221 and 06670174 from the Japanese Ministry of Education, Science, and Culture and by funds from the Ono Medical Research Fund (to T. O.), the Science Research Promotion Fund of the Japan Private School Promotion Foundation, and the Osaka Dental University Research Foundation (to T. O., H. U., H. O., and N. O.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
↵¹ The abbreviations used are:

TNF-α

tumor necrosis factor-α

C-ceramide

N-acetylsphingosine.
↵² H. Sawai and T. Okazaki, unpublished data.
- Received June 19, 1995.
- Revision received August 23, 1995.