• Toxicological Research
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• v.18 no.3
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• pp.275-283
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• 2002

Fungal metabolite, gliotoxin is an epipolythiodioxopiperazin (ETP) class and has various roles including immunomodulatory and apoptotic effects. This study was designed to evaluate the mechanism by which gliotoxin exerts the apoptosis on human promyelocytic leukemic HL-60 cells. Herein, we demonstrated that the gliotoxin decreased the cell viability in a time-dependent manner Gliotoxin-induced cell death was confirmed us apoptosis characterized by chromatin condensation and ladder-pattern fragmentation of genomic DNA. Gliotoxin increased the catalytic activities of caspase-3 and caspase-9. Activation of caspase-3 was further confirmed by degradation of procaspase-3 and poly(ADP-ribose) polymerase (PARP) by gliotoxin in HL-60 cells. Furthermore, gliotoxin induced the changes of mitochondrial transmembrane potential (MTP). Antioxidants, including GSH and NAC, markedly inhibited apoptosis with conistent suppression of enzymatic activity of caspase-3, caspase-9, and MTP loss in gliotoxin-treated cells. Taken together, we suggest that gliotoxin function as an oxidant and ploys proapoptotic roles in HL-60 cells via activation of intrinsic caspase cascades as well as mitochondrial dysfunction.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1140-1146
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• 2006

Ceramide analogs are potential chemotherapeutic agents. We report that a ceramide analog induces apoptosis in human prostate cancer cells. The ceramide analog induced cell death through an apoptotic mechanism, which was demonstrated by DNA fragmentation, the cleavage of poly ADP ribose polymerase (PARP), and a loss of membrane asymmetry. Treating the cells with ceramide analog resulted in the release of various proapoptotic mitochondrial proteins including cytochrome c and Smac/DIBLO into the cytosol, and a decrease in the mitochondrial membrane potential. In addition, the ceramide analog decreased the phospho-Akt and phospho-Bad levels. The expression of the antiapoptotic Bcl-2 decreased slightly with increasing Bax to Bcl-2 ratio. These results suggest that the ceramide analog induces apoptosis by regulating multiple signaling pathways that involve the mitochondrial pathway.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.80-80
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• 2002

Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in response to a variety of cytokines. The presence of oncogenic ras has been associated with sustained induction of COX-2, which confers resistance to apoptosis. Contrary to the above notion, we found that MCF10A-ras cells treated with an anti-tumor agent, ET-18-O-$CH_3$, underwent apoptosis as revealed by proteolytic cleavage of poly(ADP-ribose)polymerase, pro-caspase 3 activity, and TUNEL staining, while the same treatment caused an increased expression of COX-2 as well as the elevated production of prostaglandin E$_2$(PGE$_2$).(omitted)

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.62-67
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• 2012

TNF-related apoptosis-inducing ligand (TRAIL) is a promising agent for management of cancer because of its selective cytotoxicity to cancer cells. However, some cancer cells have resistance to TRAIL. Accordingly, novel treatment strategies are required to overcome TRAIL resistance. Here, we examined the synergistic apoptotic effect of apigenin in combination with TRAIL in Huh-7 cells. We found that combined treatment of TRAIL and apigenin markedly inhibited Huh-7 cell growth compared to either agent alone by inducing apoptosis. Combined treatment with apigenin and TRAIL induced chromatin condensation and the cleavage of poly (ADP-ribose) polymerase (PARP). In addition, enhanced apoptosis by TRAIL/apigenin combination was quantified by annexin V/PI flow cytometry analysis. Western blot analysis suggested that apigenin sensitizes cells to TRAIL-induced apoptosis by activating both intrinsic and extrinsic apoptotic pathway-related caspases. The augmented apoptotic effect by TRAIL/apigenin combination was accompanied by triggering mitochondria-dependent signaling pathway, as indicated by Bax/Bcl-2 ratio up-regulation. Our results demonstrate that combination of TRAIL and apigenin facilitates apoptosis in Huh-7 cells.

• Archives of Pharmacal Research
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• v.27 no.12
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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.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.297-301
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• 2004

The purpose of the present study was to investigate the anti-proliferative and apoptotic effects of MCS-C2, a novel analogue of toyocamycin and sangivamycin, in human promyelocytic leukemia (HL-60) cells. When treated with MCS-C2, inhibited proliferation associated with cell cycle arrest and apoptotic induction was found in the HL-60 cells in a concentration-dependent and time-dependent manner. This apoptotic induction was associated with the cleavage of Bid and a release of cytochrome c from mitochondria into the cytosol, followed by the activation of caspase-3 and inactivation of poly (ADP-ribose) polymerase (PARP). However, there was no significant change in any other mitochondrial membrane proteins, such as Bcl-2 and Bax. Consequently, the current findings suggest that the mitochondrial pathway was primarily involved in the MCS-C2-induced apoptosis in the human promyelocytic leukemia HL-60 cells.

• YAKHAK HOEJI
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• v.45 no.5
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• pp.484-490
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• 2001

Mylabris phalerata(MP) is an insect that has been used for the treatment of cancer in oriental medicine. To evaluate the anticancer activity of Mylabris phalerata, We measured the cytotoxicity of Mylabris phalerata solvent fractions such as MC, EA, BuOH and residual layers on U937, human monocytic leukemia cells. Of those fractions BuOH layer of Mylabris phalerata was the most effective with ID$_{50}$ of 140$\mu\textrm{g}$/ml. It effectively caused DNA fragmentation from the concentration of 50$\mu\textrm{g}$/ml, showed apoptotic nucleus by tenets assay and expressed apototic portion stained by Annexin-V. It also induced the activation of caspase-3 and cleavage of the substrate poly (ADP-ribose) polymerase (PARP). These results suggest BuOH layer of Mylabris phalerata exerts anticancer activity by induction of apoptosis via activation of caspase-3 protease.e.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.235-239
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• 2002

It has been reported that lovastatin induced cell death and suppressed proliferation in various cell lines. In this study, we examined whether the cytotoxic effects of lovastatin could be prevented by Bcl-2 or $Bcl-_{XL}$ in C6 glial cells. Overexpression of human Bcl-2 or $Bcl-_{XL}$ prevented lovastatin $(25{\mu}M)-induced$ changes such as DNA fragmentation, chromatin condensation, disruption of cell membrane, and cleavage of poly (ADP-ribose) polymerase. Lovastatin-induced inhibition of cell proliferation was unaffected by Bcl-2 or $Bcl-_{XL}$ overexpression. These results suggest that Bcl-2 and $Bcl-_{XL}$ can prevent lovastatin-induced apoptosis in C6 glial cells, though the inhibition of proliferation remains unaffected by these proteins.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.350-354
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• 2005

The effect of the essential oil obtained from Chrysanthemum boreale Makino on the apoptosis of KB cells was investigated. Cytotoxicity and cellular DNA content were analyzed by MTT assay, flow cytometry, agarose gel electrophoresis, and Hoechst 33258 staining. The caspase-3 and poly (ADP-ribose) polymerase (PARP) proteins were estimated by Western blotting method. The various cytotoxic effects of the essential oil which are hallmarks of apoptosis, including DNA fragmentation, apoptotic body formation, and sub-G1 DNA content, all progressed in a dose-dependent manner. Treatment with an apoptosis-inducing concentration of the essential oil caused rapid and transient induction of caspase 3 activity. Further, the efficacious induction of PARP cleavage and caspase-3 activation was observed at an essential oil concentration of 0.1 and 0.2 mg/mL for 12 hr.

• Natural Product Sciences
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• v.24 no.4
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• pp.293-297
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• 2018

Sasa quelpaertensis Nakai leaves contain a mixture of polysaccharides, amino acids, and polyphenols, which mediate various biological activities. For efficient utilization of its leaf, we reported the preparation procedure for phytochemical-rich extract (PRE) using the leaf residue, which was by-product of hot water extraction. This study was undertaken to evaluate the effects of PRE and its major constituent, p-coumaric acid,on the growth of several human cancer cell lines (MKN-74, MKN-45, SNU-1, SNU-16, and HL-60). The ethyl acetate fraction of PRE and p-coumaric acid significantly inhibited the proliferation of MKN-74 and HL-60 cells, respectively, and induced cell apoptosis, down-regulated Bcl-2 and poly (ADP-ribose) polymerase levels, and up-regulated those of Bax and caspase-3. These results show the potential utility of S. quelpaertensis Nakai leaves in cancer prevention.