• 제목/요약/키워드: Topoisomerase I

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Farmesy-Protein Transferase의 저해제 Dihydrotanshinone l. (Dihydrotanshinone l is an Inhibitor of Farmesy-Protein Transferase)

  • 이동선;이상한;하상철;김종국;서영배;홍순덕
    • 생명과학회지
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    • 제8권2호
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    • pp.158-161
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    • 1998
  • Farmesy-Protein Transferase의 저해제는 Ras단백질의 발암활성을 차잔하는 항암제의 후보로서 알려져있다. 우리는 최근에 topoisomerase I에 대하여 저해활성을 갖는 dihydrotanshinone I을 약용식물인 Salvia miltorhiza Bunge(Danshen)으로부터 분리하였다. Dihydrotanshinone Iml 작용기작의 해석을 위한 시도에서 farmesy-Protein Transferase에 대한 저해능($IC_{50}$치= 15ug/ml)을 관찰하였으며, 이것은 유용한 항암제로서의 가능성을 제시한 결과로 본다.

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Paralichthys olivaceous 추출물에 의한 CNA 복제 개시 단계에서의 억제 효과 (Inhibitory Effects of Extracts of Paralichtys olivaceus on DNA replication at the Level of Initiation)

  • 이지현;임영해;이수복;김동규;김동선;박남규;정준기;김남득
    • 생명과학회지
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    • 제11권4호
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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.

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A First Synthesis of Isofagar-idine:Topoisomerase I Inhibitor

  • Cho, Won-Jea;Miyoji Hanaoka
    • Archives of Pharmacal Research
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    • 제19권3호
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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.

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Biochemical Characterization of Adriamycin-Resistance in PC-14 Human Lung Adenocarcinoma Cell Line

  • Yi, Jae-Youn;Hong, Weon-Seon;Son, Young-Sook
    • BMB Reports
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    • 제34권1호
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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.

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가미청열해독탕(加味淸熱解毒湯)의 항암활성(抗癌活性)에 관(關)한 연구(硏究)( I ) (Study on Antitumor Effect of Kamicheungyeolhaedogtang(KCHT)(I))

  • 김규;김동희;최봉균;김성훈
    • 혜화의학회지
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    • 제8권2호
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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.

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캄프토테신 유도체의 리포좀 제형 개발 (Development of Liposomal Formulation of A Camptothecin Derivative)

  • 심진영;김진석
    • Journal of Pharmaceutical Investigation
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    • 제31권2호
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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.

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Synthesis, Cytotoxicity and Structure-Activity Relationship Study of Terpyridines

  • Zhao, Long-Xuan;Sherchan, Jyoti;Park, Jung-Ki;Jahng, Yurng-Dong;Jeong, Byeong-Seon;Jeong, Tae-Cheon;Lee, Chong-Soon;Lee, Eung-Seok
    • Archives of Pharmacal Research
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    • 제29권12호
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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.

A New Stilbene Glucoside from the Roots of Polygonum multiflorum Thunb.

  • Xu, Ming-Lu;Zheng, Ming Shan;Lee, Yeon-Kyong;Moon, Dong-Cheol;Lee, Chong-Soon;Woo, Mi-Hee;Jeong, Byeong-Seon;Lee, Eung-Seok;Jahng, Yurng-Dong;Chang, Hyeun-Wook;Lee, Seung-Ho;Son, Jong-Keun
    • Archives of Pharmacal Research
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    • 제29권11호
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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.

Synthesis of Benzoquinoxalines

  • Kwon, Nam-Koong;Lee, Hee-Soon
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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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.

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