Biological and Pharmaceutical Bulletin
Online ISSN : 1347-5215
Print ISSN : 0918-6158
ISSN-L : 0918-6158
An Attempt to Evaluate the Effect of Vitamin K3 Using as an Enhancer of Anticancer Agents
Sumio MatznoYuka YamaguchiTakeshi AkiyoshiToshikatsu NakabayashiKenji Matsuyama
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2008 Volume 31 Issue 6 Pages 1270-1273


The possibility of vitamin K3 (VK3) as an anticancer agent was assessed. VK3 dose-dependently diminished the cell viability (measured as esterase activity) with IC50 of 13.7 μM and Hill coefficient of 3.1 in Hep G2 cells. It also decreased the population of S phase and arrested cell cycle in the G2/M phase in a dose-dependent manner. G2/M arrest was regulated by the increment of cyclin A/cdk1 and cyclin A/cdk2 complex, and contrasting cyclin B/cdk1 complex decrease. Finally, combined application demonstrated that VK3 significantly enhanced the cytotoxicity of etoposide, a G2 phase-dependent anticancer agent, whereas it reduced the cytotoxic activity of irinotecan, a S phase-dependent agent. These findings suggest that VK3 induces G2/M arrest by inhibition of cyclin B/cdk1 complex formation, and is thus useful as an enhancer of G2 phase-dependent drugs in hepatic cancer chemotherapy.

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© 2008 The Pharmaceutical Society of Japan
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