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Publications (2)2.53 Total impact

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    ABSTRACT: Widdrol, a natural sesquiterpene present in Juniperus sp., has been shown to exert anticancer and antifungal effects. Emerging evidence has suggested that AMP-activated protein kinase (AMPK), which functions as a cellular energy sensor, is a potential therapeutic target for human cancers. In this study, we found that AMPK mediates the anticancer effects of widdrol through induction of apoptosis in HT-29 colon cancer cells. We showed that widdrol induced the phosphorylation of AMPK in a dose- and time-dependent manner. The selective AMPK inhibitor compound C abrogated the inhibitory effect of widdrol on HT-29 cell growth. In addition, we demonstrated that widdrol induced apoptosis and this was associated with the activation of caspases, including caspase‑3/7 and caspase-9, in HT-29 cells. We also demonstrated that transfection of HT-29 cells with AMPK siRNAs significantly suppressed the widdrol-mediated apoptosis and the activation of caspases. However, cell cycle arrest induced by widdrol was not affected by transfection of HT-29 cells with AMPK siRNAs. Furthermore, widdrol inhibited HT-29 tumor growth in a human tumor xenograft model. Taken together, our results suggest that the anticancer effect of widdrol may be mediated, at least in part, by induction of apoptosis via AMPK activation.
    Oncology Reports 05/2012; 27(5):1407-12. · 2.30 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the anti-tumor activity of KBH-A42, a novel synthetic histone deacetylase (HDAC) inhibitor. KBH-A42 was shown to significantly suppress the proliferation of all 14 human cancer cell lines tested. Among these cell lines, the human leukemia cell line K562 was the most sensitive, whereas the UM-UC-3 bladder cancer cells were the least sensitive. Additionally, in a human tumor xenograft model using Balb/c nude mice, KBH-A42 was shown to significantly inhibit the growth of K562 tumors, although it only slightly inhibited the growth of UM-UC-3 tumors. The results of flow cytometry analysis and caspase 3/7 activation assays showed that the growth inhibition of K562 cells by KBH-A42 was mediated, at least in part, by the induction of apoptosis, but its growth inhibitory effects on UM-UC-3 cells were not mediated by apoptotic induction. In an effort to gain insight into the mechanism by which KBH-A42 inhibits the growth of cancer cells, a microarray analysis was conducted. Four genes were selected from the genes that were down-regulated or up-regulated by KBH-A42 and confirmed via reverse transcription-polymerase chain reaction as follows: Harakiri (HRK), tumor necrosis factor receptor superfamily, member 10b (TNFRSF10B), PYD and CARD domain containing protein gene (PYCARD) and tumor necrosis factor receptor superfamily, member 8 (TNFRSF8). Collectively, the in vitro and in vivo results suggested that KBH-A42 exhibits anti-cancer activity, but various types of cells may be regulated differentially by KBH-A42.
    Oncology letters 01/2012; 3(1):113-118. · 0.24 Impact Factor