• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.394-399
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• 2003

The in vitro cytotoxic effects of newly synthesized copper (II) glycinate complex were investigated in two gastric cancer cell lines of SNU484 and SNU638 cells. The complex inhibited the growth and decreased the viability of both gastric cancer cells in a dose-dependent manner. Gastric cancer tells treated with the complex exhibited the features of apoptosis, as demonstrated by fragmentation of chromosomal DNA, activation of caspase-3-like enzyme, and cleavage of poly［ADP-ribose］ polymerase (PARP). With the treatment of copper (II) glycinate complex, the active form of caspase-3 was observed in SNU484 cells, but not in SNU638 cells, indicating that an alternative pathway of apoptosis might have been triggered in SNU638 cells. In conclusion, copper (II) glycinate complex induces apoptosis of SNU484 and SNU638 gastric cancer cells, and it is suggested that novel copper (II) glycinate complex is highly active against human gastric cancer cells.

• Development and Reproduction
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• v.26 no.3
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• pp.99-105
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• 2022

Styrene is the precursor of polystyrene. Human exposure to styrene could occur in occupational and residential settings and via food intake. Styrene is metabolized to styrene-7,8-oxide by cytochrome P450 enzyme. In the present study, we investigated the cytotoxicity mediated by styrene and styrene-7,8-oxide in TM3 testicular Leydig cells in vitro. We first monitored the nuclear fragmentation in Leydig cells after exposure to styrene or styrene-7,8-oxide. Hoechst 33258 cell staining showed that styrene exposure in TM3 Leydig cells did not exhibit nuclear fragmentation at any concentration. In contrast, nuclear fragmentation was seen in styrene-7,8-oxide-exposed cells. These results indicate that cytotoxicity-mediated cell death in Leydig cells is more susceptible to styrene-7,8-oxide than to styrene. Following styrene treatment, procaspase-3 and XIAP protein levels did not show significant changes, and cleaved (active) forms of caspase-3 were not detected. Consistent with the western blot results, the active forms of caspase-3 and XIAP proteins were not prominently altered in the cytoplasm of cells treated with styrene. In contrast to styrene, styrene-7,8-oxide induced cell death in an apoptotic fashion, as seen in caspase-3 activation and increased the expression of XIAP proteins. Taken together, the results obtained in this study demonstrate a fundamental idea that Leydig cells are capable of protecting themselves from cytotoxicity-mediated apoptosis as a result of styrene exposure in vitro. It remains unclear whether the steroid-producing function, i.e., steroidogenesis, of Leydig cells is also unaffected by exposure to styrene. Therefore, further studies are needed to elucidate the endocrine disrupting potential of styrene in Leydig cells.

• Animal cells and systems
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• v.4 no.4
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• pp.381-388
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• 2000

Using a murine T cell hybridoma, activation-induced cell death (AICD) was studied. As an in vitro model system for the AICD, 1 cell hybridoma expressing TCR/CD3 complex was incubated onto the immobilized purified anti-CD3 antibody. The immobilized anti-CD3 antibody induced AICD effectively up to 40%. At 1-100 $\mu$M range of SNP, an exogenous source of nitric oxide (NO), the cell proliferation was not affected, but at 1 mM SNP, cell proliferation was significantly reduced. The AICD of T cell hybridoma was inhibited by exogenous NO at non-cytotoxic concentration, In the cells undergoing AICD, the expressions of caspase-3 and FasL were detected, but not iNOS. Similar result was recognized in the apoptosis induced by dexamethasone, an apoptosis-inducing agent. However, the conversion from the inactive form of caspase-3 (32 kDa) to the active form (17 kDa) was significantly reduced in the cells in AICD induced by anti-CD3 antibody, With the result of increased PARP cleavage in the cells, we propose that another PARP cleavage pathway not involving caspase-3 may function in the anti-CD3 antibody induced AICD in the T cell hybridoma.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.231-243
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• 1998

In the present study, we provide evidence that ginsenoside $Rh_2$ (G-$Rh_2$) as well as staurosporine induces apoptosis of human hepatoma SK-HEP-1 cells by caspase 3-mediated processing of $p21^{WAFI/CIPI}$ in the early stage of apoptosls. Immunoblottings showed that G-$Rh_2$ as well as statrosporine induced the processing of caspase-3 to an active form, pl7. In stable Bcl-2 transfectants however, G-$Rh_2$ induced DNA fragmentation, while staurosporine did not. In the early stage of apoptosis, $p21^{WAFI/CIPI}$ was detected to undergo proteolytic processing specifically conducted by caspase-3. $p21^{WAFI/CIPI}$ translated in vitro was cleaved into a p14 fragment, when incubated with cell extracts obtained from either G-$Rh_2$- or staurosporine-treated cells. Cleavage was equally inhibited in both cases by adding Ac-DEVD-cho, a specific caspase-3 inhibitor, but not by Ac-YVkD-cho, a specific caspase-l inhibitor. Similarly, $p21^{WAFI/CIPI}$ was efficiently leaved by recombinant caspase-3 overexpressed in E. coli. Moreover, the endogenous $p21^{WAFI/CIPI}$ of untreated-cell extracts was also cleaved by recombinant caspase-3. Mutation analysis allowed identification of two caspase-3 cleavage sites, $DHVD^{112}$/L and $SMTD^{149}$/F, which are located within, or near the interaction domains for cyclins, Cdks, and PCNA. Taken together, these results show that G-$Rh_2$ as well as staurosporine increases caspase-3 activity, which in turn directly cleaves $p21^{WAFI/CIPI}$ resulting in elevation of Cdk kinase activity in the early stages of apoptosis. We propose that proteolytic cleavage of $p21^{WAFI/CIPI}$ is a functionally relevant event that allows unleashing the cyclin/Cdk activity from the inhibitor seen in the earlier stage of apoptosis, the event of which may be associated with the triggering mechanism for the execution of apoptosis.

• The Journal of Internal Korean Medicine
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• v.32 no.4
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• pp.565-583
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• 2011

Objectives : This study investigated the biochemical mechanisms of anti-proliferative and pro-apoptotic effects of the water extract of Dan-Seon-Tang (DST) in human leukemia U937 cells. Methods : U937 cells were exposed to DST and growth inhibition was measured by MTT assay. Results : Exposure of U937 cells to DST resulted in the growth inhibition in a concentration-dependent manner. This inhibitory effect was associated with morphological changes and apoptotic cell death such as formation of apoptotic bodies, increased populations of apoptotic-sub G1 phase and induction of DNA fragmentation. The induction of apoptotic cell death in U937 cells by DST was associated with up-regulation of death receptor 4 (DR4) and down-regulation of Bid, surviving and cellular inhibition of apoptosis protein-2 (cIAP-2) expression. DST treatment also induced the proteolytic activation of caspase-3, caspase-8 and caspase-9, and a concomitant degradation of caspase-3 substrate proteins such as poly (ADP-ribose) polymerase (PARP), phospholipase (PLC)-${\gamma}1$, ${\beta}$-catenin and DNA fragmentation factor 45/inhibotor of caspase activated DNAse (DFF45/ICAD). Furthermore, apoptotic cell death by DST was significantly inhibited by caspase-3 specific inhibitor z-DEVD-fmk, demonstrating the important role of caspase-3. Conclusions : These findings suggest that herb prescription DST may be a potential chemotherapeutic agent for the control of human leukemia U937 cells; further study is needed to identify the active compounds.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.286-290
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• 2009

In the course of screening for substances inhibiting apoptosis of U937 human leukemia cells induced by etoposide ($10\;{\mu}g/ml$), Forsythiae fructus, which showed a high level of inhibition, was selected. The regulating compounds were purified from the ethyl acetate extract by silica gel column chromatography and HPLC. The active substance was purified and identified as rengyolone by spectroscopic methods. This compound showed inhibitory activity on caspase-3 induction, a major protease of the apoptosis cascade, with an $IC_{50}$ value of $38.96\;{\mu}M$ after 8 h of etoposide treatment in U937 cells. The expression level of caspase-3 and poly(ADP-ribose) polymerase (PARP) were dose-dependently inhibited by the compound, suggesting that rengyolone inhibits etoposide-induced apoptosis via downregulation of caspases.

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.169-183
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• 2003

Tooth movement by orthodontic force effects great tissue changes within the periodontium, especially by shifting the blood flow in the pressure side and resulting in a hypoxic state of low oxygen tension. The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3El osteoblasts, the main cells in bone remodeling during orthodontic tooth movement. MC3T3El osteoblasts under hypoxic conditions ($2\%$ orygen) resulted in apoptosis in a time-dependent manner as estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pancaspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, Western blot analysis was performed using anti-caspase-3 or -6 antibodies. The 10-kDa protein, corresponding to the active products of caspase-3, and the 10-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which the processing of the full length form of caspase-3 and -6 was evident. While a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, which was typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we observed that pre-treatment with SB203580, a selective p38 mitogen activated protein kinase inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203S80 suppressed caspase-3 and -6-like protease activity by hypoxia up to $50\%$. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAPK -JNK/SAPK or ERK- was either only modestly activated or not at all. These results suggest that p38 MAPK is involved in hypoxia-induced apoptosis in MC3T3El osteoblasts.

• Toxicological Research
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• v.19 no.3
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• pp.197-203
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• 2003

Apicidin, a histone-deacetylase inhibitor, has been successfully used to inhibit the growth of cancer cells. In this study, the apoptotic potential and mechanistic insights of apicidin were investigated in human myeloid leukemia U937 cells. Treatment of U937 cells with apicidin resulted in a decrease of cell viability with apoptotic characteristics, including chromatin condensation and ladder-pattern fragmentation of genomic DNA. Apicidin converted the procaspase-3 protease to catalytically active effector protease, resulting in subsequent cleavage of poly (ADP-ribose) polymerase (PARP) and inhibitor of caspase-activated deoxyribonuclease (ICAD). In addition, apicidin induced the activation of caspase-9 protease and the cytosolic release of mitochondrial cytochrome c with mitochon-drial membrane potential transition. Moreover, apicidin transiently increased the expression of Fas and Fas ligand proteins. Taken together, the results suggest that apicidin induces apoptosis of U937 cells through activation of intrinsic caspase cascades and Fas/FasL system with mitochondrial dysfunction.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.319-324
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• 2003

This study examined the inhibitory effect of extracts of Trichosanthes kirilpwii sorted according to the parts on the growth of HL-60 cells. The growth of HL-60 leukemia cells was markedly inhibited by the treatment of the 80％ methanol extract of roots (10 $\mu\textrm{g}$/mι), stems (50$\mu\textrm{g}$/mι), pips (10$\mu\textrm{g}$/mι), and gourds (100 $\mu\textrm{g}$/mι), or the ethylacetate fraction of leaves (100 $\mu\textrm{g}$/mι). when the HL-60 cells were treated with the extracts of T. kirilpwii sorted according to the parts, DNA fragmentation and sub-G1 hypodiploid cells were observed. Moreover, T. kirilpwii extracts increased the level of the expression of the active form of caspase-3 and the activation of caspase-3 was demonstrated by the cleavage of poly(ADP-ribose) polymerase, a vital substrate of effector caspase. The results suggest that the inhibitory effect of extracts of T. kirilpwii sorted according to the parts on the growth of HL-60 cells seems to arise from the induction of apoptosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1563-1567
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• 2005

Mori Cortex Radicis is distributed in Northwestern China, northern Asia, northern Europe, North America, and Korea. This extracts drops sugar in bloods and inhibits cyclic AMP phophodiesterase. In this study, we investigated whether Mori Cortex Radicis would cause apoptotic death of A549 lung cancer cells. To examine the apoptotic effect of Mori Cortex Radicis, cytotoxicity assay, DNA fragmentation analysis, caspase-3 activity assay, and Western blotting for caspase-3, caspase-9 and poly(ADP-ribose) polymerase (PARP) and cytochrome c were performed. Treatment of cells with Mori Cortex Radicis was shown to induce cell death in a dose-dependent manner. DNA fragmentation was made in response to Mori Cortex Radicis. The active fragments of caspase-3, caspase-9 and PARP were almost completely induced and cytochrome c was released following exposure to Mori Cortex Radicis. To elucidate the apoptotic mechanisms, RT-PCR and Western blot analyses for the expression of Bcl-2, Bu and Cox-2 were carried out. Treatment with Mori Cortex Radicis was expressed the reduction of Bcl-2 and Cox-2 and the induction of Bax. Especially p21 and p53 were increased prior to untreated control, while cyclin E and cyclin D1 decreased in the cytosol. These results suggest that the effect Mori Cortex Radicis is associated with the cell cycle arrest and pro-apoptotic cell death in A549 lung cancer cells.