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Publications (6)7.27 Total impact

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    ABSTRACT: Berberine (BBR) has been used for the treatment of bacterial and fungal infections and also for cancer-associated symptoms such as diarrhea. Furthermore, it has been reported that BBR may have direct antitumor effects. Although evidence supports the theory that tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a promising candidate for treating cancer, its usage may be limited due to the resistance to the TRAIL-induced apoptosis of cancer cells. In the present study, the effect of BBR on TRAIL-induced antitumor effects was investigated in vitro using recombinant TRAIL and in vivo using a 4T1 murine breast cancer model in combination with anti-DR5 (death-inducing TRAIL receptor) monoclonal antibody therapy. BBR sensitized human breast cancer cell lines to TRAIL-mediated apoptosis in vitro. The combination of BBR and recombinant TRAIL significantly activated caspase-3 and PARP cleavage in TRAIL-resistant MDA-MB-468 cells. Furthermore, BBR in combination with TRAIL more effectively induced apoptosis compared with coptisine (COP), which is structurally related to BBR. In a murine 4T1 breast cancer model, BBR treatment enhanced the efficacy of anti-DR5 antibody therapy against primary tumor growth and lung metastasis. Thus, BBR may become a new adjuvant for overcoming the resistance of cancer cells to TRAIL/DR5-mediated therapy.
    Oncology letters 09/2013; 6(3):840-844. · 0.24 Impact Factor
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    ABSTRACT: We have performed a broad-ranging analysis of the adjuvant effect of a Kampo medicine, juzentaihoto (JTT), on influenza vaccination in a multicenter randomized controlled trial. In this study, the enhancing effect of JTT on antibody titer after influenza vaccination was studied for 28 weeks in elderly people who were in the high-risk group for influenza infection. In total, 91 subjects over 65 years old were recruited from four long-term-care facilities located in Chiba, Gunma, and Toyama prefectures in Japan. Participants were randomly assigned to the JTT and the control groups. Blood samples were taken at 4 weeks before vaccination, at the time of vaccination, and then at 4, 8, 12, and 24 weeks after vaccination. The hemagglutination inhibition (HI) titers against A/California/7/2009 (H1N1), A/Victoria/210/2009 (H3N2), and B/Brisbane/60/2008 were then manually measured. A significant increase in HI titer against H3N2 was observed at week 8 after vaccination in the JTT group compared with the control group (P = 0.0229), and the HI titer of the JTT group significantly increased from 4 to 24 weeks (P = 0.0468), compared with the control group. In conclusion, our results indicated that JTT increased and prolonged antibody production against A/Victoria/210/2009 (H3N2), in particular, after influenza vaccination.
    Evidence-based Complementary and Alternative Medicine 01/2013; 2013:568074. · 1.72 Impact Factor
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    ABSTRACT: Pharmacological studies have revealed that lignans isolated from Schisandra chinensis, including gomisin N, show anticancer, anti-hepatotoxic, anti-oxidative and anti-inflammatory activities. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an important member of the tumor necrosis factor superfamily with great potential in cancer therapy. The present study investigated whether pretreatment with gomisin N significantly enhanced TRAIL-induced cleavage of caspase-3, caspase-8 and PARP-1, which are key markers of apoptosis. Pretreatment with z-VAD-FMK, a pan-caspase inhibitor, was able to inhibit apoptosis enhanced by the combination of gomisin N and TRAIL. These results suggested that gomisin N could promote TRAIL-induced apoptosis through the caspase cascade. In search of the molecular mechanisms, we elucidated that such enhancement was achieved through transcriptional up-regulation of TRAIL receptors, death receptor 4 (DR4) and DR5. Neutralization of DR4 and DR5 could significantly reduce apoptosis induced by gomisin N and TRAIL. We also revealed that gomisin N increased the generation of reactive oxygen species (ROS). N-acetyl cysteine (NAC), an antioxidant, could inhibit ROS production and up-regulation of DR4 and DR5. Overall, our results indicated that gomisin N was able to potentiate TRAIL-induced apoptosis through ROS-mediated up-regulation of DR4 and DR5.
    International Journal of Oncology 12/2011; 40(4):1058-65. · 2.66 Impact Factor
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    ABSTRACT: Tumor necrosis factor-alpha (TNF-α) and TNF-related apoptosis-inducing ligand (TRAIL) are apoptosis-inducing ligands that stimulate death receptors. In this study, we investigated the effects of bufotalin, a major compound in toad venom, on sensitizing TNF-α and TRAIL-induced apoptosis of HeLa cells. Bufotalin promoted death receptor-mediated cell death, especially TRAIL-induced apoptosis, through activation of caspase-3 and PARP-1. Mitochondrial Bid-dependent pathway was activated in TNF-α-induced cell death. Cotreatment of bufotalin with TRAIL resulted in the downregulation of anti-apoptotic proteins, including Bcl-XL, Mcl-1, survivin and XIAP, and the up-regulation of MAPKs and TRAIL receptor DR5. In addition, phosphorylation of STAT1 was strongly inhibited by bufotalin. Moreover, DR5 expression was induced by knocking down the STAT1 expression. Moreover, the TRAIL-induced apoptotic response was promoted by STAT1 siRNA. Our results demonstrated that bufotalin is a powerful sensitizer of death receptor-induced apoptosis in cancer cells.
    International Journal of Oncology 09/2011; 40(1):203-8. · 2.66 Impact Factor
  • Kampo Medicine 01/2007; 58(6):1133-1137.
  • Kampo Medicine 01/2007; 58(5):861-865.