Involvement of caspase activation and mitochondrial stress in trichostatin A-induced apoptosis of Burkitt's lymphoma cell line, Akata.
Epstein-Barr virus (EBV) infects more than 90% of the human population and has a potential oncogenic nature. Trichostatin A (TSA) has potent antitumor activity, but its exact mechanism on EBV-infected cells is unclear. This study examined the effects of TSA on proliferation and apoptosis of the Burkitt's lymphoma cell line, Akata. TSA treatment inhibited cell growth and induced cytotoxicity in both the EBV-negative and -positive Akata cells. TSA sensitively induced apoptosis in both cells, as demonstrated by the increased number of positively stained cells in the TUNEL assay, the migration of many cells to sub-G1 phase by flow cytometric analysis, and the formation of DNA ladders. This suggests that EBV has no effect on the sensitivity to TSA. Western blot analysis showed that the cleavage of PARP and Bid and the activation of caspases are closely related to the TSA-induced apoptosis of the cells. The reduction in mitochondrial transition potential and the release of apoptosis-inducing factor from mitochondria to cytosol was also observed after the TSA treatment, but was suppressed by treating the cells with a cathepsin B inhibitor. Overall, these findings suggest that besides the caspase-dependent pathway, mitochondrial events are also associated with the TSA-induced apoptosis of Akata cells.
Son
Young-Ok
YO
Division of Biological Sciences, Chonbuk National University, Chonju 561-756, Korea.
Choi
Ki-Choon
KC
Lee
Jeong-Chae
JC
Kook
Sung-Ho
SH
Lee
Hyun-Jeong
HJ
Jeon
Young-Mi
YM
Kim
Jong-Ghee
JG
Kim
Ju
J
Lee
Won-Keun
WK
Jang
Yong-Suk
YS
D017209:Apoptosis / Q000187:drug effects*; D051023:BH3 Interacting Domain Death Agonist Protein / Q000378:metabolism; D002051:Burkitt Lymphoma; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004249:DNA Damage; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004854:Herpesvirus 4, Human / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology*; D020287:In Situ Nick-End Labeling; D008928:Mitochondria / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism
D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D004791:Enzyme Inhibitors; D006877:Hydroxamic Acids; C012589:trichostatin A; D011065:Poly(ADP-ribose) Polymerases; D020169:Caspases