• 미생물학회지
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• 제42권1호
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• pp.47-53
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• 2006

한국 토양에서 방선균주를 분리하고 화학 분류 및 16S rDNA 염기서열을 통하여 Streptomyces 속 균주임을 알아내고 Streptomyces sp. AO-0511로 명명하였다. 이 균주가 생산하는 herbimycin A 및 dihydroherbimycin A의 몇 가지 이화학적 성질과 생물 활성을 측정하였다. 두 물질은 모두 산성 조건에서 안정성을 나타냈으며, dihydroherbimycin A는 herbimycin A에 비해 상대적으로 높은 열 안정성을 지니며 극성 또한 높은 물질로서 TLC 상의 Rf간이 낮았다. Herbimycin A와 dihydroherbimycin A는 모두 Bacillus subtilis ATCC 6633 및 Micrococcus luteus ATCC 9341에 대하여 약한 저해 활성을 나타내었고, 다른 미생물에 대해서는 저해 활성을 나타내지 앓았다. 항암 활성에 있어서 두 물질은 폐암 세포인 AS49세포와 백혈병 세포인 HL-60세포에 대해서 강력한 중식 저해 활성을 나타내었다. L5178Y및 P388세포를 사용하여 세포 독성을 측정하였다. 그 결과 두 물질은 대조 물질인 camptothecin에 비해서 항암 활성을 가지면서도 비교적 안전한 물질임을 알려 주고 있다.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1057-1064
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• 2005

Apoptosis may occur in early embryos where the execution of essential developmental events has failed, and gangliosides, sialic acid-conjugated glycosphingolipids, are proposed to regulate cell differentiation and growth. To evaluate the regulatory roles of ganglioside GM3 in early embryonic development, this study examined its expressional patterns in apoptotic cells during early embryonic development in mice. Pre-implanted embryos were obtained by in vitro fertilization, which were treated at the 4-cell stage with three the apoptosis inducers, actinomycin D, camptothecin and cycloheximide, for 15 h. All three inducers significantly increased the percentage of apoptotic cells, as measured using a TUNEL method, but remarkably reduced the total cell numbers. The numbers of morula and blastocyst stages were significantly decreased by treatment of the embryos with the three apoptosis inducers compared with the control, with a similar result also observed in the number of blastomeres. Staining of early embryos with Hoechst 33342 revealed a significant percentage of apoptotic nuclei. Prominent immunofluo­rescence microscopy revealed a significant difference in the ganglioside GM3 expression in apoptotic embryos compared with the control, and RT-PCR also demonstrated a dramatic increase in ganglioside GM3 synthase mRNA in the apoptotic embryos. These results suggest that ganglioside GM3 may be pathophysiologically implicated in the regulation of early embryonic development through an apoptotic mechanism.

• Biomolecules & Therapeutics
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• 제12권1호
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• pp.49-54
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• 2004

The present study was conducted to investigate the potential subacute toxicity of CKD-602 by a 5-day repeated intravenous administration in Sprague-Dawley rats. CKD-602 was administered intravenously to male rats at dose levels of 0, 0.08, 0.2, and 0.5 mg/kg for 5 days. Studies included general observation, body weight changes, ophthalmoscopic examination, hematology, se겨m biochemistry, gross findings at necropsy and organ weight measurement. There were no deaths in any treatment group and treatment related clinical sign was depilation in the 0.5 mg/kg groups. The decrease or suppression of body weight was also observed dose-dependently in all treatment groups. Decreased leukocyte in all treatment groups, decreased platelet in the above 0.2 mg/kg groups and increase in the serum levels of total cholesterol in the 0.5 mg/kg group were considered as a treatment related toxic effects. Decreased weight of thymus in all treatment groups anti decreased weight of spleen in the above 0.2 mg/kg group were observed. The intravenous administration of CKD-602 caused depilation and decreased weight and had toxic effect on the leukocyte, platelet, spleen and thymus. In the condition of this study, the target organs were spleen and thymus and the toxic effect level was determined to be 0.2 mg/kg, but no-observed-adverse-effect level (NOAEL) was considered to be lower than 0.08 mg/kg.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.71-71
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• 1993

Carboxylesterase is widely distributed in the tissues of vertebrates, insects, plants and mycobacteria. Among various tissues of animals and humans, the highest esterase activity with various substrates is found in the liver. Kidney has moderate carboxylesterase activity in the proximal tubules. Considerable esterase activity is also found in the small intestine epithet elial cells and serum of mammals. Besides these tissues, carboxylesterase has been found in the lung, testis, adipose tissue, nasal mucosa and even in the central nervous system. Hepatic microsomal carboxylesterase catalyzes the hydrolysis of a wide variety of endogenous and exogenous compounds such as carboxylester, thioester and aromatic amide. Since carboxylesterases are important for metabolic activation of prodrugs and detoxification of xenobiotics, differences in substrate specificity and immunological properties of this enzyme are important in connection with choosing a suitable laboratory animal for the evaluation of biotransformation and toxicity of drugs. On the other hand, liver, kidney, intestine and serum were found to contain multiple forms of carboxylesterases in animal species and humans. In fact, we have purified more than fifteen isoforms of carboxylesterases from microsomes of liver, kidney and intestinal mucosa of nine animal species and humans. and characteristics of these isoforms were compared each other in terms of their physical and immunochemical properties. On the other hand, we have reported that hepatic microsomal carboxylesterases are induced by many exogenous compounds such as phenobarbital, polycyclic aromatic hydrocarbons, Aroclor 1254, aminopyrine and clofibrate. Later, we showed that some isoforms of hepatic carboxylesterase were induced by glucocorticoids such as dexamethasone and 16 ${\alpha}$-carbonitrile, but other isoforms were rather inhibited by these compounds. These findings indicate that involvement of carboxylesterases in the metabolism and toxicity of drugs should be explained by the isoforms involved. Since 1991, we have carried out detailed research investigating the types of carboxylesterases involved in the metabolic activation of CPT-11, a derivative of camptothecin, to the active metabolite, SN-38. The results obtained strongly suggest that some isoforms of carboxylesterase of liver microsomes and intestinal mucosal membrane are exclusively involved in CPT-11 metabolism. In this symposium, the properties of carboxylesterase isoforms purified from liver, kidney and intestine of animal species and humans are outlined. In addition, metabolism of CPT-11, a novel antitumor agent, by carboxylesterases in relation to the effectiveness will also be discussed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권1호
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• pp.7-12
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• 2005

Purpose: CKD-602, a newly developed water-soluble campthotecin analogue, is a anticancer agent which act as a DNA topoisomerase I inhibitor. CKD-602 is known as more potent and tolerable agent. The main purposes of this study were to measure the cytotoxic effect of CKD-602 on the oral cancer cell lines and to evaluate the apoptotic aspect of dead cells. Materials and Methods: To determine the cytotoxic effect of CKD-602 on the oral cancer cell lines in comparison with various cell lines, such as lung cancer and colon cancer cell lines, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was performed. And apoptosis was analyzed using fluorescence-activated cell sorting(FACS) system. Results: CKD-602 decreased the viability of malignant cells in a dose dependent manner and in a time dependent manner. CKD-602 showed excellent cytotoxicity to the oral cancer cell lines. Also, apoptotic portion was increased in a dose dependent manner. Conclusion: These findings indicated that CKD-602 induced apoptotic cell death in the various cell lines including oral cancer cell lines. From the results, it was suggested that CKD-602 would be a potential therapeutic agent for the oral cancer. More successive researches on the anticancer effect of CKD-602 should be performed.

• 약학회지
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• 제53권4호
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• pp.228-234
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• 2009

Topoisomerase I (Topo I) participates in the DNA replication, transcription, and repair. Binding of Topo I inhibitor to the Topo I-DNA cleavage complex forms stabilized ternary complex which blocks DNA religation and ultimately causes cell death. Camptothecin (CPT) and its derivatives have been among the most effective anticancer drugs by inhibition of topo I. However, efforts to synthesize non-CPT drugs have been actively going on because the CPT derivatives have several limitations such as poor solubility, short half-life, and side effects. As an indenoisoquinoline, NSC314622 is not as potent as CPT, but its chemical stability and slower reversibility of the cleavage complex made it a good lead compound. Recently, a series of indenoisoquinoline analogues were synthesized with substituted dimethoxy or methylenedioxy on the aromatic ring and alkylamino on the lactam nitrogen. Some of them showed quite good Topo I inhibitory activity. Using the computer docking program, Surflex-Dock, indenoisoquinoline analogues were docked into the human Topo I-DNA cleavable complex. The docking results showed that the compounds with activity better than NSC314622 intercalated between the -1 and +1 base pairs at the cleavage site, but those with little or no activities did not appear to intercalate. These results could be useful to design new Topo I inhibitors improved than CPT.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.633-643
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• 2017

To examine the pro-apoptotic role of the human ortholog (YPEL5) of the Drosophila Yippee protein, the cell viability of Saccharomyces cerevisiae mutant strain with deleted MOH1, the yeast ortholog, was compared with that of the wild-type (WT)-MOH1 strain after exposure to different apoptogenic stimulants, including UV irradiation, methyl methanesulfonate (MMS), camptothecin (CPT), heat shock, and hyperosmotic shock. The $moh1{\Delta}$ mutant exhibited enhanced cell viability compared with the WT-MOH1 strain when treated with lethal UV irradiation, 1.8 mM MMS, $100{\mu}M$ CPT, heat shock at $50^{\circ}C$, or 1.2 M KCl. At the same time, the level of Moh1 protein was commonly up-regulated in the WT-MOH1 strain as was that of Ynk1 protein, which is known as a marker for DNA damage. Although the enhanced UV resistance of the $moh1{\Delta}$ mutant largely disappeared following transformation with the yeast MOH1 gene or one of the human YPEL1-YPEL5 genes, the transformant bearing pYES2-YPEL5 was more sensitive to lethal UV irradiation and its UV sensitivity was similar to that of the WT-MOH1 strain. Under these conditions, the UV irradiation-induced apoptotic events, such as FITC-Annexin V stainability, mitochondrial membrane potential (${\Delta}{\psi}m$) loss, and metacaspase activation, occurred to a much lesser extent in the $moh1{\Delta}$ mutant compared with the WT-MOH1 strain and the mutant strain bearing pYES2-MOH1 or pYES2-YPEL5. These results demonstrate the functional conservation between yeast Moh1 and human YPEL5, and their involvement in mitochondria-dependent apoptosis induced by DNA damage.

• Biomolecules & Therapeutics
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• 제12권1호
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• pp.43-48
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• 2004

The present study was carried out to investigate the potential acute toxicity of CKD-602 by a single intravenous dose in Sprague-Dawley rats. Ten males females were used in each test groups: a vehicle control, 34.7, 4l.7, 50.0, 60.0 and 72.0 mg/kg groups, and were given different single intravenous doses of CKD-602 to the test animals. Mortalities, clinical findings, and body weight changes were monitored for the 14-day period following the administration. At the end of l4-day observation period, all animals were sacrificed and complete gross postmortem examinations were performed. One, 1, 2, 8 and 9 cases of deaths occurred in the male dose groups of 34.7, 41.7, 50.0, 60.0 and 72.0 mg/kg, respectively, and 1, 5 and 9 cases in the female dose groups 50.0, 60.0 and 72.0 mg/kg, respectively. An increase in the incidence of clinical signs such as alopecia, skin pallor skin ulcerations, emaciation and change of fecal material was found in the both sexes of all treatment groups. A decrease or Suppression in the body weight was also observed in a dose-dependent manner. In autopsy, male and/or female rats of the treatment groups showed treatment-related gross findings such as splenomegaly, atrophy of the testis, epididymis, seminal vesicles, ovary, uterus and thymus which were dose-dependent in incidence and severity. Based on these results, it was concluded that a single intravenous injection of CKD-602 to rats caused significant toxicities in gastrointestinal, hematopoietic, and reproductive systems. The $LD_{50}$ value was 53.8 (95% confidence limit: 48.5~60.6) mg/kg for males and 60.l (95% confidence limit: 55.3~65.8) mg/kg for females. The $LD_{10}$ value was 39.9 (95% confidence limit: 3l.7~44.8) mg/kg for males and 50.3 (95% confidence limit: 40.6~54.8) mg/kg for females.

• Archives of Pharmacal Research
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• 제27권1호
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• pp.77-82
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• 2004

DA-125, a novel derivative of adriamycin, is known for its anti-cancer activity. In this study, the inhibitory mechanism of DA-125 on topoisomerase was investigated in the simian virus 40 (SV40) replicating CV-1 cell by studying the SV40 DNA replication intermediates and DNA-topoisomerase complexes. DNA-protein complexes that were formed in the drug-treated cells were quantitated by using a glass filter assay. SV40 DNA replication intermediates that were accumulated in the drug-treated CV-1 cell were analyzed in a high resolution gel. DA-125 did not accumulate B-dimers of SV40 DNA replication intermediates which were found in the adriamycin-treated CV-1 cells. DA-125 induced a dose-dependent formation of the DNA-protein complexes, while adriamycin did not. When adriamycin and etoposide (VP16) were added to the SV40-infected cells at the same time, adriamycin blocked the formation of the DNA-protein complexes induced by VP16 in a dose-dependent manner. However, DA-125 blocked the formation of the DNA-protein complexes induced by VP16 up to the maximum level of the DNA-protein complexes that were induced by DA-125 alone. Adriamycin and DA-125 did not inhibit the formation of the DNA-protein complexes that were caused by camptothecin, a known topoisomerase I poison. DA-125 is bifunctional in inhibiting topoisomerase II because it simultaneously has the properties of the topoisomerase II poison and the DNA intercalator. As a topoisomerase II poison, DA-125 alone induced dose-dependent formation of the DNA-protein complexes. However, as a DNA intercalator, it quantitatively inhibited the formation of the DNA-protein complexes induced by a strong topoisomerase II poison VP16. Furthermore considering that the levels of the DNA-protein complex induced by VP16 were decreased by DA-125 in terms of the topoisomerase II poison, we suggest that DA-125 has a higher affinity to the drug-binding sites of DNA than VP16 has.

• Tuberculosis and Respiratory Diseases
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• 제52권3호
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• pp.230-240
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• 2002

연구배경 : 소세포폐암은 1차 화학요법에 반응율은 높으나 대부분이 1차 화학요법 1년이내에 진행하고 재발하여, 2차 화학요법에 대한 반응율 및 생존율은 매우 불량하다. 최근 들어 camptothecin 유도체로서 topoiso-merase I 억제제인 topotecan이 소세포폐암의 확장 기에서 1차요법으로서 단독사용시에 39%의 반응율과 10개월의 중앙생존기간이 보고되고 있어, 소세포 폐암의 1차화학요법후 진행, 재발시에 2차요법으로 사용하여 반응율, 생존율 및 부작용등을 검토하였다. 대상 및 방법 : 소세포폐암으로 진단받은 후 1차 화학요법 3주기 시 행후 반응이 없었던 9예와 1차 화학요법 6 주기 완료 후 재발한 10 예, 총 19예를 대상으로 topotecan (hycamtin$^{(R)}$, Glaxo-Smith-Kline, USA) 1.5mg/$m^2$을 매 3주 간격으로 첫 1일부터 5일까지 5일간 30분간에 걸쳐 정맥 투여를 총 6주기 실시하여, 3주기와 6주기후에 반응을 측정하였고, 생존율은 Kaplan-Meier법으로 구하였고, 비교군끼리의 생존율 비교는 Log-rank 검정하였다. 결 과 : 전 대상군에서의 반응율은 26.3% (5/19, CR 2, PR 3, SD 3, PD 11) 이었고, 중앙생존기간은 24주였으며, 1차화학요법의 무반응군 (9예)과 반응군(10예)의 반응율은 각각 22.2%(2/9, PR 2, SD 3, PD 4), 30%(3/10, CR 2, PR 1, PD 7)이었고, 중앙생존기간은 각각 17주, 24주였으며, 1차 화학요법 완료 3개월 이내와 3개월 이후에 재발한 refractory군(6 예)과 sensitive군 (4예)의 반응율은 각각 16.6%(1/6, CR 1, PD 5),50%(2/4, CR 1, PR 1, PD 2)이었고, 중앙생존기간은 각각 14주, 39주였고, 제한기(9예)와 확장기 (10예)의 반응율은 각각 44.4% (4/9, CR 2, PR 2, SD 1, PD 4),10.0%(1/10, PR 1, SD 2, PD 7)이었고 중앙생존기간은 각각 36 주로서 대사예가 적어 통계적 유의성에 이르지는 못하였으나 1차요법 반응군, 1차요법후 늦게 재발한 sensitive군, 제한기의 반응율 및 생존율이 비교적 양호하였다. Topotecan의 유의할 만한 독성 부작용은 전 90주기의 화학요법중 빈혈 grade III 1예, 백혈구 감소증 grade III 6 예, IV 4 예, 혈소판 감소증 grade III 1 예, IV 1예 였으며 구토는 grade III 1예였다. 결 론 : 소세포폐암의 2차 화학요법으로서 topotecan 단독요법은 반응율 26.3%, 중앙생존기간은 24주였으며, 1차 화학요법에 반응을 보인군, 1차 화학요법 완료후 늦게 재발한 군, 제한기의 반응율 및 생존율이 양호하였으며, 더 나아가 다른 2차 화학요법과의 임상대조 시험이 있어야겠다.