• Journal of Life Science
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• v.8 no.2
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• pp.158-161
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• 1998

An inhibitor of farnesy-protein transferae is known to be a fgood candidate for antitumor agent that block the oncogenic activity of Ras protein . We recently isolated and characterized dihydrotanshinone I from Salvia miltiorrhiza Bunge (Danshen), an oriental herb, which has an inhibitory activity of toposimerase I to some cancer cell lines. In order to examine the molecular mechanism of dihydrotanshinone I, we studied the farmesy-Protein Transferase activity by dihydrotanshinone I. As a result, we found that result, we found that dihydrotanshinone I showed inhibitory effect on farnesyl-protein transferase with $IC_{50}$ value of 15 ug/ml. This result suggest that dihydrotanshinone I may be an useful anticancer agent with the inhibitory activity of farnesyl-protein transferase.

• Journal of Life Science
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• v.11 no.4
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• pp.371-378
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• 2001

The effects of the RM 60 series on DNA replication systems were examined by using simian virus 40 (SV40) DNA replication system in vitro. The RM 60 series inhibited the DNA replication in the initiation step rather than in the elongation step. Polymerase$\alpha$-primase activity and toposiomerase I activity study were performed subsequently, the RM 60 seies increased the polymerase $\alpha$-primase activity in a low dose, but decreased the activity in a higher dose. The topoisomerase I activity was inhibited by the RM 60 series. This result suggests that the RM 60 series might inhibit some molecules which are required to establish replication forks during the initiation step of the DNA replication.

• Archives of Pharmacal Research
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• v.19 no.3
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• pp.240-242
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• 1996

We have reported the convenient biomimetic methodology for the synthesis of all kinds of substituent pattern benzo[c]phenanthridine alkaloids (Hanaoka et al., 1990; Hanaoka et al., 1991). Regioselective demethylation of C-8 position on oxyfagaridine (5), an intermediate for the synthesis of Fagaridine (4), would afford the precursor for the synthesis of Isofagaridine because the strong hydrogen bonding between amide and hydroxyl group of C-7 position probably resists to be reacted with week base and electrophiles. Thus, a selective alkylation of dihydroxy compound supposed to be possible and be lead to the target compound, Isofagaridine.

• BMB Reports
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• v.34 no.1
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• pp.66-72
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• 2001

To investigate the mechanism of adriamycin (ADM) resistance in the ADM resistant subline PC-14/ADM, we examined the expressions of p-glycoprotein (P-gp), topoisomerase I (Topo I) and II (Topo II), glutathione-S-transferases (GSTs), tissue transglutaminase (t-TG), epidermal growth factor receptor (EGFR), and E-cadherin and the activity of superoxide dismutase (SOD) in PC-14 and PC-14/ADM cells. There was no change in the cellular levels of P-gp, Topo I, Topo II, and the two isoforms of GSTs. However, SOD activity in PC-14/ADM cells was 2.38 fold higher than that in PC-14 cells. A marked induction of the t-TG expression was also observed in PC-14/ADM cells. In addition to those changes, expressions of EGFR and E-cadherin were down regulated in PC-14/ADM cells. Therefore, molecular modifications such as an increase in SOD activity, induction of the t-TG expression, and down regulation of EGFR and E-cadherin expressions may play important roles in PC-14/ADM cells during the development of ADM resistance.

• Journal of Haehwa Medicine
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• v.8 no.2
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• pp.93-106
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• 2000

To evaluate the antitumor activity and antimetastatic effects of Kamicheungyeolhaedog tang(KCHT), studies were done experimentally. The results were obtained as follows: 1. KCHT extracts exhibited a significant cytotoxicity against A549, SK-MEL-2, SK-OV-3, and B16-BL6 cell lines. 2. KCHT extracts showed significant inhibitoty effect on DNA topoisomerase I 3. The T/C% was 145.8% in KCHT treated group in S-180 bearing ICR mice. 4. KCHT extracts exhibited efficient affect adhesive effect of A549, B16-BL6 cell to complex extracellular matrix. 5. In vitro neovascularization assays, angiogenesis was insignificantly inhibited in KCHT treated group as compared with control group. These results suggested that KCHT extracts might be usefully applied for prevention and treatement of cancer.

• Journal of Pharmaceutical Investigation
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• v.31 no.2
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• pp.113-117
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• 2001

CKD602, a camptothecin derivative, is a synthetic and water-soluble anticancer agent possessing of topoisomerase I inhibiting activity. DPPC and DSPE-PEG liposomal formulations entrapped with CKD602 were developed. DSPE-PEG liposome, or PEGylated liposome, encapsulating CKD602 composed of dipalmitoylphosphatidylcholine (DPPC), cholesterol and distearoyl-N-monoethoxy poly (ethyleneglycol) succinylphosphatidylethanolamine $(DSPE-PEG_{2000})$ (22:11:2) was prepared by reverse-phase evaporation method. Formed liposomes were characterized in terms of the morphology, size and encapsulation efficiency. To elucidate the in vitro stability, PEGylated liposome was incubated in human plasma, and the adsorbed proteins onto the surface of liposomes were applied to the SDS-PAGE. In vitro cytotoxicity of CKD602 encapsulated in PEGylated liposome was studied in human cervical cancer cell line (HeLa). CKD602 in PEGylated liposome was found to be 40-fold more effective $(IC_{50}=1\;nM)$ than free CKD602 $(IC_{50}=40\;nM)$ in inhibiting the growth of HeLa cells in vitro.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.214.1-214
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• 2001

No Abstract, See Full Text

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1091-1095
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• 2006

For the development of novel antitumor agents, we designed and synthesized terpyridines, and their biological activities were evaluated. Although most of the newly prepared terpyridines showed strong cytotoxicity against several human cancer cell lines, [2,2';6',2"]-terpyridine displayed the most significant cytotoxicity.

• Archives of Pharmacal Research
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• v.29 no.11
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• pp.946-951
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• 2006

One new stilbene glucoside (6), along with five known compounds (1-5), were isolated from the roots of Polygonum multiflorum Thumb., and their chemical structures established based on physicochemical and spectroscopic data. Of the compounds, compound 3 showed DNA topoisomerase I and II inhibitory activities.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.351.2-351.2
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• 2002

We have previously reported the synthesis and cytotoxic activities of a series of azaanthraquinone derivatives on the model of doxorubicin(Dox). Dox is known to intercalate into DNA and to inhibit topoisomerase II activity. But in the case of Quinone compounds like Dox. its use is limited because of systemic toxicities. primarily cardiotoxicity and myelosuppression. In this study. we describe the synthesis of benzoquinoxaline derivatives as DACA analogue. DACA has a neutral chromophore and acridine moiety and posions both topoisomerases I and ll with DNA intercalating activity. In order to delineate the SAR of benzoquinoxaline derivatives. an effcient sythetic rout to the target compounds without quinone group. Various attempted removal of quinone from benzoquinoxlinedione was unsuccessful. Diels-Alder rout applied for the synthesis of the target compounds will be discussed.