15-Deoxy-delta12,14-prostaglandin J2, a ligand for peroxisome proliferators-activated receptor-gamma, induces apoptosis in human hepatoma cells.
OBJECTIVE
15-deoxy-delta12,14-prostaglandin J2 (15-d-PGJ2) induces apoptosis in several carcinoma cell lines and is a potent activator of peroxisome proliferators-activated receptor-gamma (PPAR-gamma). In the present study, we examined the effect of 15-d-PGJ2 on human hepatoma cells.


METHODS
HuH-7 and HepG2 cell lines were used in all the experiments. The mRNA expression of PPAR-gamma was studied by reverse transcriptase-polymerase chain reaction. The cell viability was determined by a modified MTT assay. Two methods were used for the determination of apoptosis in hepatoma cells: the TUNEL assay, and detection of fragmented mono- and oligo-nucleosomes by ELISA.


RESULTS
The expression of PPAR-gamma mRNA and protein was detected in HuH-7 and HepG2. Treatment with 15-d-PGJ2 decreased cell viability in a time- and dose-dependent manner. 15-d-PGJ2 induced apoptosis and this effect was time-dependent. Exposure of cells to 15-d-PGJ2 induced caspase-3 and -9 activation. Furthermore, co-treatment with the pan-caspase inhibitor Z-VAD-FMK or the caspase-3 inhibitor Z-DEVD-FMK blocked apoptosis of human hepatoma cells that had been treated with 15-d-PGJ2.


CONCLUSIONS
Our study demonstrates that PPAR-gamma is expressed in human hepatoma cell lines and that treatment with 15-d-PGJ2 inhibits the growth of these cells by inducing apoptosis through caspase activation.
Department of Pharmacology, Osaka Dental University, Hirakata, Japan. date@cc.osaka-dent.ac.jp
Masataka
M
Date
Kazuhide
K
Fukuchi
Shosuke
S
Morita
Hiroshi
H
Takahashi
Kiyoshi
K
Ohura
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000503:physiopathology*; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor / Q000187:drug effects / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology*; D020287:In Situ Nick-End Labeling; D008113:Liver Neoplasms / Q000378:metabolism / Q000503:physiopathology*; D009842:Oligopeptides / Q000494:pharmacology; D015230:Prostaglandin D2 / Q000031:analogs & derivatives* / Q000494:pharmacology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000378:metabolism*
C097240:15-deoxy-delta(12,14)-prostaglandin J2; D000590:Amino Acid Chloromethyl Ketones; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D007155:Immunologic Factors; D009842:Oligopeptides; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; C110772:benzoylcarbonyl-aspartyl-glutamyl-valyl-aspartyl-fluoromethyl ketone; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D020169:Caspases; D015230:Prostaglandin D2