Apoptosis induction by gamma-tocotrienol in human hepatoma Hep3B cells.
We evaluated the antitumor activity of tocotrienol (T3) on human hepatoma Hep3B cells. At first, we examined the effect of T3 on the proliferation of human hepatoma Hep3B cells and found that gamma-T3 inhibited cell proliferation at lower concentrations and shorter treatment times than alpha-T3. Then, we examined the effect of gamma-T3 apoptosis induction and found that gamma-T3 induced poly (ADP-ribose) polymerase (PARP) cleavage and stimulated a rise in caspase-3 activity. In addition, gamma-T3 stimulated a rise in caspase-8 and caspase-9 activities. We also found that gamma-T3-induced apoptotic cell death was accompanied by up-regulation of Bax and a rise in the fragments of Bid and caspase-8. These data indicate that gamma-T3 induced apoptosis in Hep3B cells and that caspase-8 and caspase-9 were involved in apoptosis induction. Moreover, these results suggest that Bax and Bid regulated apoptosis induction by gamma-T3.
Sakai
Midori
M
Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
Okabe
Masaaki
M
Tachibana
Hirofumi
H
Yamada
Koji
K
D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D002839:Chromans / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D019254:Genes, bcl-2 / Q000187:drug effects; D006801:Humans; D008113:Liver Neoplasms; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D024508:Tocotrienols; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000494:pharmacology
D002839:Chromans; D024508:Tocotrienols; D014810:Vitamin E; C082097:tocotrienol, delta; C013649:plastochromanol 8; C082032:tocotrienol, alpha; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases