• Toxicological Research
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• 제18권2호
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• pp.183-190
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• 2002

The mechanism by which catechin-mediated cytotoxicity against tumor cells remains to be elusive. To elucidate the mechanical mights of anti-tumor effects, (-)epigallocatechin-gallate (EGCG) of catechin was applied to human prostate cancer DU 145 cells. Cell viability was measured by crystal violet staining. Cell lysates were wed to measure the catalytic activity of caspases by using fluorogenic peptide: Ac-DEVD-AMC for caspase-3 protease, Z-IETD-AFC for caspase-8 protease, Ac-LEHD-AFC for caspase-9 protease as substrates. The equal amounts of protein from cell lysate was separated on SDS-PAGE and analyzed by western blotting with anti-Fas antibody, anti-FasL antibody, anti-BCL2 antibody and anti-Bax antibody. (-)EGCG induced the death of DUl45 cells, which was revealed as apoptosis shown by DNA fragmentation. (-)EGCG induced the activation of caspase family cysteine proteases including caspase-3, -8 and -9 proteases in DU145 cells. Also, (-)EGCG increased the expression of Fas and Fas ligand (FasL) protein in DU145 colls. The expression level of BCL2 was decreased in (-)EGCG treated DU145 cells, whereas Bax protein was increased in a time-dependent manner. We suggest that (-)EGCG-induced apoptosis of DU145 cells is mediated by signaling pathway involving caspase family cysteine protease, mitochondrial BCL2-family protein and Fas/FasL.

• Journal of Life Science
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• 제9권1호
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• pp.58-63
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• 1999

Highly metastatic mouse T-lymphoma CS21 cells can grow in vitro when cocultured with CA12 lymph node stromal cells, but they undergo apoptotic cell death when separated from CA12 stromal cells. It has been found that cysteine and interleukin-7(IL-7) as antiapoptotic soluble factors that produced by CA12 stromal cells. In this study, we report that an ICE family protease is activated in CS21 cells when separated from CA12 stromal cells and cultured alone. Enzyme purification using an avidin affinity column revealed that the involved cysteine protease possessed caspase3-like death protease activity. In addition, when IL-7 was added to CS21 cell culture, the protease activity could not be detected during partial purification of the enzyme. Taken together, these results strongly suggest that the caspase3-like protease activation is suppressed by IL-7 as an antiapoptotic factor that leads to abrogation of apoptosis execution.

• Tuberculosis and Respiratory Diseases
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• 제53권5호
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• pp.485-496
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• 2002

연구 방법 : Nonsteroidal anti -inflammatory drugs (NSAIDs)는 대장앙의 항암 예방약제로 사용되고 었다 지속적으로 NSAIDs를 복용하면 대장암에 걸릴 위험도가 40-50% 감소되는 것으로 알려져 있다. NSAIDs가 대장암에서 종양의 크기를 감소시키는 것에 대한 정확한 기전은 알려져 있지 않으나, 일부 연구자들은 NSAIDs를 고농도로 투여하였을 때 세포 주기를 조절하는 유전자 발현의 변형과 세포고사의 유도로 설명하고 있다. 그러나 폐암에서 NSAIDs의 암 예방효과에 대해 확립 된 바 없어, 저자들은 NCI-H1299 세포주에서 NSAIDs가 세포고사를 유도하는지 알아보고자 하였다. 방 법 : 세포 독성은 MTT 방법으로 측정하였고, 세포고사를 알아보기 위해 유세포 분석과 핵산 염색을 시행하였다. 세포고사의 기전을 알아보기 위해 caspase family의 활성을 측정하였고, 세포고사의 마지막 단계인 PARP와 ICAD의 분절을 westem blot으로 확인하였다. 결 과 : NCI-H1299 세포에서 NaSaL 처리 시 생존율이 농도와 시간에 의존적으로 유의하게 감소하였고, 생존율의 감소는 세포주기에서 $subG_0/G_1$의 증가와 핵산 염색시 핵의 분절의 관찰로서 세포고사가 일어남을 관찰하였다. 10 mM NaSaL 처리 후 caspase-3 protease의 활성은 24시간에 증가하여 30시간에 최고에 이르고 감소하였으나 caspase-6, 8, 9 proteases의 활성은 의미 있는 증가가 없었다. PARP와 ICAD의 분절은 농도와 시간 의존적으로 증가하였다. 결 론 : NCI-H1299 폐암 세포주에서 NaSaL은 caspase-3 protease의 활성을 통하여 유도되었다.

• 생물정신의학
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• 제5권2호
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• pp.219-226
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• 1998

Cytosine arabinoside(AraC) inhibits DNA synthesis and ${\beta}$-DNA polymerase, an enzyme involved in DNA repair. This, a potent antimitotic agent, is clinically used as an anticancer drug with side effect of severe neurotoxicity. Earlier reports suggested that inhibition of neuronal survival by AraC in sympathetic neuron may be due to the inhibition of a 2'-deoxycytidine-dependent process that is independent of DNA synthesis or repair and AraC induced a signal that is triggers a cascade of new mRNA and protein synthesis, leading to apoptotic cell death in cultured cerebellar granule cells. The present study would suggest whether caspase family(ICE/CED-3-like protease) involved in AraC-induced apoptosis pathway of PC12 cells. It was observed that treatment of PC12 cells with AraC led to decrease of viability by MTT assay and morphology changes, which did not suggest that AraC induced apoptosis in PC12 cells. The mRNA of caspase-1/caspase-3 were expressed in PC12 cells constitutively, and AraC did not activate caspase family. These results suggest that caspase-1/caspase-3 may not be required for AraC-induced cell death pathway in PC12 cells.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.1003-1010
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• 2002

Caspase 3, a member of cysteine protease family, is well known as a major apoptosis effector and is involved in cell death as a result of ischemic diseases such as stroke and myocardial infarction, therefore the inhibition of caspase 3 may protect those apoptotic cell damages. During the high-throughput screening of the compounds from the Korea Chemical Bank, berberine derivatives (A and B), an isoquinoline alkaloid, have been identified as potential inhibitors for caspase 3. Based on this finding we carried out molecular modeling study to identify the pharmacophoric elements of berberine structure which interact with a substrate-recognition binding site of caspase 3 and came up with several novel scaffolds. In this report, we will discuss the molecular modeling, syntheses and the enzyme inhibitory activities of these novel compounds.

• 한국영양학회:학술대회논문집
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• 한국영양학회 2000년도 추계학술대회 초록
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• pp.62-62
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• 2000

• 동의생리병리학회지
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• 제18권3호
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• pp.759-766
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• 2004

In the present study, we investigated the effects of aqueous extract of the healthful decoction utilizing Phellinus linteus (HDPL) on the cell growth of human lung carcinoma tumor cell line A549. Exposure of A549 cells to HDPL resulted in growth inhibition and induction of apoptosis in a dose-dependent manner as measured by hemocytometer counts, fluorescence microscopy and flow cytometric analysis. This increase in apoptosis was associated with inhibition and/or degradation of apoptotic target proteins such as poly(ADP-ribose) polymerase (PARP), b-catenin and phospholipase C- 1 (PLC- 1) protein. HDPL treatment induced the down-regulation of anti-apoptotic Bcl-2 expression, an anti-apoptotic gene, however, the level of Bax. a pro-apoptotic gene, was increased by HDPL treatment. In addition, HDPL-induced apoptotis of A549 cells was connected with activation of caspase-3 and caspase-9 protease in a dose-dependent manner, however, the levels of inhibitor of apoptosis proteins family were remained unchanged. Taken together, these results indicated that the anti-proliferative effects of HDPL were associated with the induction of apoptotic cell death through regulation of several major growth regulatory gene products such as Bcl-2 family expression and caspase protease activity, and HDPL may have therapeutic potential in human lung cancer.

• Journal of Nutrition and Health
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• 제35권1호
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• pp.53-59
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• 2002

Green tea has been recognized as a favorite beverage for centuries in Easter and Westers cultures. Recently, anti-tumor effects of green tea constituents have received increasing attention. However, the mechanism of catechin-mediated cytotoxicity against tumor cells remains to be elusive. To elucidate the mechanical insights of anti-tumor effects, (-)epigallocatechin-gallate(EGCG) of catechin was applied to human lung cancer A549 cells. (-)EGCG induced the death of A549 cells, which was revealed as apoptosis in DNA fragmentation assay. (-)EGCG induced the activation of caspase family cysteine proteases including capase-3, -8 and -9 proteases in A549 cells. Furthermore, (-)EGCG increased the phosphotransferase activity of c-Jun N-terminal kinase 1JNK 1), which further induced tole transcriptional activation of activating protein-1(AP-1) in A549 cells. We suggest that (-)EGCG-induced apotosis of A549 cells is mediated by signaling pathway involving caspase family cysteine protease, JNK1 and transcription factor, AP-1.

• BMB Reports
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• 제35권1호
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• pp.116-126
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• 2002

Nitric oxide (NO), synthesized from L-arginine by NO synthases, is a small, lipophilic, diffusible, highly reactive molecule with dichotomous regulatory roles in many biological events under physiological and pathological conditions. NO can promote apoptosis (pro-apoptosis) in some cells, whereas it inhibits apoptosis (anti-apoptosis) in other cells. This complexity is a consequence of the rate of NO production and the interaction with biological molecules such as metal ion, thiol, protein tyrosine, and reactive oxygen species. Long-lasting overproduction of NO acts as a pro-apoptotic modulator, activating caspase family proteases through the release of mitochondrial cytochrome c into cytosol, up-regulation of the p53 expression, and alterations in the expression of apoptosis-associated proteins, including the Bcl-2 family. However, low or physiological concentrations of NO prevent cells from apoptosis that is induced by the trophic factor withdrawal, Fas, $TNF{\alpha}$/ActD, and LPS. The anti-apoptotic mechanism is understood on the basis of gene transcription of protective proteins. These include: heat shock protein, hemeoxygenase, or cyclooxygenase-2 and direct inhibition of the apoptotic executive effectors caspase family protease by S-nitrosylation of the cysteine thiol group in their catalytic site in a cell specific way. Our current understanding of the mechanisms by which NO exerts both pro- and anti-apototic action is discussed in this review article.

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1253-1257
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• 2004

6-Methoxydihydrosanguinarine (6ME), a benzophenanthridine alkaloid derived from the methanol extracts of Hylomecon hylomeconoides, showed a dose-dependent effect at 1-10 ${\mu}M$ on causing apoptotic cell death in HT29 colon carcinoma cells $(IC_{50} = 5.0{\pm}0.2 {\mu}M)$. Treatment of HT-29 cells with 6ME resulted in the formation of internucleosomal DNA fragmentation. Treatment of the cells with 6ME caused activation of caspase-3, -8 and 9 protease and subsequent proteolytic cleavage of poly(ADP-ribose)polymerase. 6ME increased the expression of p53 and Bax and decreased the expression of Bid. These results indicate that p53 and proapoptotic Bcl-2 family proteins might participate in the antiproliferative activity of 6ME in HT29 cells.