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Yongin si, South Korea

Yoon Y.J.,Korea Research Institute of Bioscience and Biotechnology | Kim J.A.,Korea Research Institute of Bioscience and Biotechnology | Kim J.A.,Korean University of Science and Technology | Shin K.D.,Korea Research Institute of Bioscience and Biotechnology | And 10 more authors.
Journal of Biological Chemistry | Year: 2011

Heat shock factor 1 (HSF1) is the master switch for heat shock protein (HSP) expression in eukaryotes. A synthetic chemical library was screened to identify inhibitors of HSF1 using a luciferase reporter under the control of a heat shock element. A compound named KRIBB11 (N2-(1H-indazole-5-yl)- N6-methyl-3-nitropyridine-2,6-diamine) was identified for its activity in abolishing the heat shock-induced luciferase activity with an IC50 of 1.2 μmol/liter. When the cells were exposed to heat shock in the presence of KRIBB11, the induction of HSF1 downstream target proteins such as HSP27 and HSP70 was blocked. In addition, treatment of HCT-116 cells with KRIBB11 induced growth arrest and apoptosis. Markers of apoptosis, such as cleaved poly(ADPribose) polymerase, were detected after KRIBB11 treatment. Biotinyl-KRIBB11 was synthesized as an affinity probe for the identification of KRIBB11 target proteins. Using affinity chromatography and competition assays, KRIBB11 was shown to associate with HSF1 in vitro. Chromatin immunoprecipitation analysis showed that KRIBB11 inhibited HSF1-dependent recruitment of p-TEFb (positive transcription elongation factor b) to the hsp70 promoter. Finally, intraperitoneal treatment of nude mice with KRIBB11 at 50 mg/kg resulted in a 47.4% (p < 0.05) inhibition of tumor growth without body weight loss. Immunoblotting assays showed that the expression of HSP70 was lower in KRIBB11-treated tumor tissue than in control tissues. Because HSPs are expressed at high levels in a wide range of tumors, these results strengthen the rationale for targeting HSF1 in cancer therapy. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

Dong Wha Pharmaceutical Co . and TEIJIN PHARMA Ltd | Date: 2010-01-29

The object of the present invention is to provide a therapeutic agent or a prophylactic agent for a disease resulting from an abnormal bone metabolism, especially osteoporosis which is more effective than conventional agents. Excellent therapeutic effect or prophylactic effect on a disease resulting from an abnormal bone metabolism, especially osteoporosis, compared with the effect in administration of each compound alone can be obtained by the combination of an N-hydroxybenzamidine derivative represented by Formula (I) or a salt thereof with an activated vitamin D or a prodrug thereof.

Park J.H.,Yonsei University | Jang Y.-J.,Yonsei University | Choi Y.J.,Yonsei University | Jang J.W.,Yonsei University | And 6 more authors.
Nutrition and Cancer | Year: 2013

Matrix metalloproteinases (MMPs) play an important role in tissue remodeling during normal physiological situations and pathological implications such as tumor invasion and metastasis. MMP inhibitors were screened from extracts of medicinal herbs by an enzymatic assay using the MMP-14 catalytic domain. Among samples tested, a methanol extract of the root of Dalbergia odorifera T. CHEN (Leguminosae) showed the strongest inhibitory activity. The inhibitory component was purified through fractionation methods and identified as fisetin, abundant in many fruits and vegetables. In addition to inhibition of MMP-14, fisetin inhibits MMP-1, MMP-3, MMP-7, and MMP-9, more efficiently than a naturally occurring MMP inhibitor tetracycline. Fisetin dose-dependently inhibits proliferation of fibrosarcoma HT-1080 cells and human umbilical vascular endothelial cells (HUVECs), MMP-14-mediated activation of proMMP-2 in HT-1080 cells, invasiveness of HT-1080 cells, and in vitro tube formation of HUVECs. Therefore, fisetin could be valuable as a chemopreventive agent against cancer and a lead compound for development of therapeutic MMP inhibitors. © 2013 Taylor and Francis Group, LLC.

Yoon J.,Dong Wha Pharmaceutical Company | Yoon J.,Seoul National University | Lee H.,Dong Wha Pharmaceutical Company | Chang H.B.,Dong Wha Pharmaceutical Company | And 7 more authors.
American Journal of Physiology - Renal Physiology | Year: 2014

DW1029M is a botanical extract consisting of Morus bark and Puerariae radix, produced by Dong-Wha Pharmaceutical, for nephroprotective drug development; it has been in phase II clinical trials in Korea. In our mechanistic investigations, we found that DW1029M inhibits advanced glycation end products (AGEs), rat lens aldose reductase (RLAR), and transforming growth factor (TGF)-β1 signaling, all of which are implicated in diabetic complications such as diabetic nephropathy and diabetic retinopathy. DW1029M inhibits AGE formation via Fe2+ chelation. The extract contains 13 active constituents that inhibit AGE formation, 8 active constituents that inhibit RLAR activity, and 1 inhibitor of TGF-β1 signaling. Our results suggest DW1029M protects against diabetic nephropathy via blockade of AGE formation, RLAR activity, and TGF-β1 signaling. © 2014 the American Physiological Society.

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