1.zVAD-fmk, unlike BocD-fmk, does not inhibit caspase-6 acting on 14-3-3/Bad pathway in apoptosis of p815 mastocytoma cells.
Su Bog YEE ; Soo Jin BAEK ; Hwan Tae PARK ; Seung Hun JEONG ; Jin Hee JEONG ; Tae Hyun KIM ; Jong Min KIM ; Byung Kap JEONG ; Bong Soo PARK ; Taeg Kyu KWON ; Il YOON ; Young Hyun YOO
Experimental & Molecular Medicine 2006;38(6):634-642
In a preliminary study, we found that benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD- fmk), unlike Boc-aspartyl(OMe)-fluoromethylketone (BocD-fmk), at usual dosage could not prevent genistein-induced apoptosis of p815 mastocytoma cells. This study was undertaken to reveal the mechanism underlying the incapability of zVAD-fmk in preventing this type of apoptosis. We observed that 14-3-3 protein level was reduced in genistein-treated cells and that BocD-fmk but not zVAD-fmk prevented the reduction of 14-3-3 protein level and the release of Bad from 14-3-3. We also demonstrated that truncated Bad to Bcl-xL interaction in genistein- treated cells was prevented by BocD-fmk but not by zVAD-fmk treatment. Our data indicate that BocD- fmk, compared to zVAD-fmk, has a certain preference for inhibiting 14-3-3/Bad signalling pathway. We also elucidated that this differential efficacy of BocD-fmk and zVAD-fmk resulted from the different effect in inhibiting caspase-6 and that co-treatment of zVAD-fmk and caspase-6 specific inhibitor substantially prevented genistein-induced apoptosis. Our data shows that caspase-6 plays a role on Bad/14-3-3 pathway in genistein-induced apoptosis of p815 cells, and that the usual dose of zVAD-fmk, in contrast to BocD-fmk, did not prevent caspase-6 acting on 14-3-3/Bad-mediated event.
bcl-Associated Death Protein/*metabolism
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*Signal Transduction/drug effects
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Mitochondria/drug effects
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Mice
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Mastocytoma
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Hydrocarbons, Fluorinated/*pharmacology
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Genistein/pharmacology
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Enzyme Inhibitors/*pharmacology
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Cell Line, Tumor
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Caspase 6/antagonists & inhibitors/*metabolism
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Benzyl Compounds/*pharmacology
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Apoptosis/*drug effects
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Animals
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Amino Acid Chloromethyl Ketones/pharmacology
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14-3-3 Proteins/*metabolism