• Journal of Nutrition and Health
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• v.36 no.4
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• pp.382-388
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• 2003

(-)-Epigallocatechin-3-gallate (EGCG) is a polyphenolic compound found in peen tea leaves, and has been known to be one of the most potent catechin species which inhibits cell growth most possibly through an apoptotic cell death. We investigated the apoptotic activity of (-)-EGCG on the human myeloid leukemia cell line, HL-60. Our results of MTT test indicated that (-)-EGCG had a significant antiproliferation effect in HL-60 cells with $IC_{50}$/ (50% inhibition concentration) value of 65 $\mu$M. Giemsa statining of HL-60 cells treated with (-)-EGCG (100 $\mu$M) for 6hrs showed a typical apoptosis-specific morphological change including shrinkage of the cytoplasm, membrane blobbing and compaction of the nuclear chromatin. The DNA fragmentation was observed from the agarose gel electrophoresis of cells treated with (-)-EGCG for 3hrs or longer, and was progressed to a greater degree as treatment time increases. Treatment of the cells with (-)-EGCG (100 $\mu$M) resulted in a rapid release of mitochondrial cytochrome c into the cytosol, and a subsequent cleavage of caspase-3 to an active form in a treatment-time dependent manner. (-)-EGCG (100 $\mu$M) also stimulated proteolytic cleavage of poly-(ADP-ribose) polymerase (PARP) to an active form in HL-60 cells. Tlken together, (-)-EGCG appears to induce the apoptosis in human myeloid leukemia cells via a caspase-dependent pathway. These results suggest the possible application of (-)-EGCG, the major active compound in green tea, as an antiproliferative agent for cancer prevention.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.303-307
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• 2003

Tributyltin (TBT) used world-wide in antifouling paints toy ships is a wide-spread environmental pollutant. At low doses, antiproliferative modes of action have been shown to be involved, whereas at higher doses apoptosis seems to be the mechanism of toxicity in reproductive organs by TBT. In this study, we investigated that the mechanisms underlying apoptosis induced by TBT in R2C cell. Effects of TBT on intracellular $Ca^{2+}$ level and reactive oxygen species (ROS) were investigated in R2C cells by fluorescence detector. TBT significantly induced intracellular $Ca^{2+}$ level in a time-dependent manner. The rise in intracellular $Ca^{2+}$ level was followed by a time-dependent generation of reactive oxygen species (ROS) at the cytosol level. Simultaneously, TBT induced the release of cytochrome c from the mitochondrial membrane into the cytosol. Furthermore, ROS production and the release of cytochrome c were reduced by BAPTA, an intracellular $Ca^{2+}$ chelator, indicating the important role of $Ca^{2+}$ in R2C during these early intracellular events. In addition, Z-DEVD FMB, a caspase -3 inhibitor, decreased apoptosis by TBT. Taken together, the present results indicated that the apoptotic pathway by TBT might start with an increase in intracellular $Ca^{2+}$ level, continues with release of ROS and cytochrome c from mitochondria, activation of caspases, and finally results in DNA fragmentation.

• International Journal of Oral Biology
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• v.40 no.4
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• pp.223-228
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• 2015

6-Gingerol exerts anti-tumor effects in various cancer cell models. We evaluated the effect of 6-gingerol on the growth of MCF-7 breast cancer cells and MCF-10A breast epithelial cells to determine whether any growth-inhibitory effects found were attributable to apoptosis, and to elucidate the underlying mechanism of action. 6-Gingerol inhibited the viability of both cell lines in a dose- and time-dependent manner; however, the degree of inhibition was greater in MCF-7 than MCF-10A cells. By flow cytometry, induction of dose- and time-dependent apoptosis was found, and the magnitude of apoptosis was also markedly greater in MCF-7 than MCF-10A cells. Expression of caspase-3 and poly (ADP-ribose) polymerase (PARP) was observed in MCF-7 cells treated with 6-gingerol, and further cleavage of PARP occurred in these cells. We suggest that 6-gingerol induces apoptosis in human breast cancer cells mainly by promoting caspase-3 expression and subsequent degradation of PARP.

• Molecules and Cells
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• v.21 no.2
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• pp.218-223
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• 2006

The effect of poly(ADP-ribosyl)ation on the stability of p53 in SK-HEP1 cells treated with UV light was examined. Intracellular levels of p53 increased in cells treated with a low dose of UV light ($20J/m^2$), whereas they increased but then declined after a higher dose of UV ($100J/m^2$). Intracellular levels of p53 in the UV treated SK-HEP1 cells were dependent on the UV dose. Use of proteasome inhibitors revealed that p53 is degraded by proteasomal proteolysis after high doses of UV light. We present evidence that, at low doses, poly(ADP-ribose)polymerase (PARP) poly(ADP-ribosyl) ates p53 and protects it from proteasomal degradation before caspase-3 is activated, whereas at high doses the cells undergo UV induced apoptosis and PARP is cleaved by caspase-3 before it can protect p53 from degradation. Destabilization of p53 by cleavage of PARP may be important in cell fate decision favoring apoptosis.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1790-1794
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• 2012

Recently, it has been suggested that $p27^{Kip1}$, the cell cycle regulatory protein, plays a pivotal role in the progression of normal differentiation in murine embryonic stem (mES) cells. In the current study, we investigated the role of $p27^{Kip1}$ in the regulation of differentiation and apoptotic induction using Western blotting, quantitative real-time RT-PCR, and small interfering RNA (siRNA) assays and confocal laser scanning microscopic analysis of H9 human ES (hES) cells and H9-derived embryoid bodies (EBs) grown for 10 ($EB_{10}$) and 20 days ($EB_{20}$). Our results demonstrate that the proteins $p27^{Kip1}$ and cyclin D3 are strongly associated with cellular differentiation, and, for the first time, show that up-regulation of $p27^{Kip1}$ protects hES cells from inducing differentiation-associated and caspase 3-dependent apoptosis.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.464-472
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• 2022

The present study was designed to investigate the antiproliferative activity and molecular mechanisms of Bibimbap in HT-29 human colorectal adenocarcinoma cells. Bibimbap extract inhibited the proliferation of HT-29 cells by 50% at a concentration of 10.1±0.17 mg/mL for 48 h. The population of live cells decreased slightly, and the morphology changed with a reduction in cell volume (pyknosis) with Bibimbap. Treatment with 5 mg/mL of Bibimbap resulted in slight cell shrinkage. Furthermore, as the Bibimbap dose increased to 10 mg/mL, these characteristics were more evident, and HT-29 cells exhibited partial detachment by staining with the DNA-binding dye Hoechst 33342. Flow cytometric analysis by Annexin V and PI double staining showed that Bibimbap increased the levels of apoptosis. Analysis of the mechanism of these events showed that Bibimbap-treated cells exhibited a mitochondria-dependent apoptotic pathway through the modulation of caspase-3, caspase-8, caspase-9, and poly-ADP ribose polymerase, as well as Bax and Bcl-2 expression in dose- and time-dependent manners. Consequently, Bibimbap exerts a significant antiproliferative effect on HT-29 human colorectal adenocarcinoma cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.516-523
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• 2006

The mushroom Inonotus obliquue (IO) has been traditionally used for the treatment of gastrointestinal cancer in Russia, Poland, and most of Baltic countries. To explore the possibility that IO has chemoprevention effects, we examined whether or not the aqueous extract of IO inhibits HT-29 cell growth and investigated tile mechanism for this effect. Cells were incubated in the presence of increasing concentrations of the aqueous extract of IO. The extract substantially inhibited the viable HT-29 cell number in a dose-dependent manner and inhibited 5-bromo-2'-deoxyuridine incorporation into DNA of HT-29 cells. Annexin-V staining followed by flow cytometry revealed that the extract induced apoptosis of HT-29 cells in a dose-dependent manner. Western blot analysis of total cell lysates revealed that the extract induced cleavage of caspase-8, -9 and -3 and poly (ADP-ribose) polymerase, but did not affect the protein levels of Bax and Bcl-2. In addition, the extract dose-dependently increased the activity of caspase-8, -9 and -3. We have demonstrated that the aqueous extract of IO inhibits cell proliferation and induces apoptosis in HT-29 cells, which may be mediated by its ability to activate the caspase pathway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1422-1429
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• 2016

Kombucha is a slightly sour beverage fermented by symbiotic micro-organisms, including bacteria and yeasts. In this study, we examined the biological activities of citrus Kombucha (CK) produced by addition of citrus extract to original Kombucha (K). After fermentation for 10 days, radical scavenging activity examined by ABTS and DPPH assays increased by approximately 20% compared to that of K. Moreover, content of total phenolic compounds significantly increased by 60% compared to that of K. Cell proliferation assays utilizing MTT showed that CK treatment significantly inhibited growth of bladder cancer cells, T-24 and 5637, in a dose-dependent manner with $IC_{50}$ values of 4 and 7 mg/mL, respectively. Annexin V staining showed that CK treatment led to apoptosis of cells in a dose-dependent manner. T-24 cells were more sensitive to CK treatment than 5637 cells, as 8 mg/mL of CK resulted in 97% apoptosis of T-24 cells. Western blotting showed that CK treatment led to up-regulation of apoptotic proteins, including caspases-3, -8, -9, and PARP, in bladder cells not in K-treated cells. Taken together, these results demonstrate that CK may be developed as a functional beverage.

• Journal of Life Science
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• v.18 no.6
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• pp.804-813
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• 2008

Cordyceps militaris, the Chinese medicinal fungal genus Cordyceps, is reported to possess many pharmacological activities including immunological stimulating, anti-cancer, anti-virus and anti-infection activities. However, the molecular mechanisms of C. militaris on biochemical actions in cancer have not been clearly elucidated yet. In the present study, we investigated the anti-proliferative activity of the water extract of C. militaris (WECM) in human hepatocellular carcinoma HepG2 cells. It was found that WECM could inhibit the cell growth in a dose-dependent manner, which was associated with morphological changes and apoptotic cell death such as formation of apoptotic bodies and increased populations of apoptotic sub-G1 phase. Apoptotic cell death of HepG2 cells by WECM was connected with a up-regulation of pro-apoptotic Bax expression, tumor suppressor p53 and cyclin-dependent kinase inhibitor p21 (WAF1/CIP1). In addition, WECM treatment induced the proteolytic activation of caspase-3 and a concomitant degradation and/or inhibition of poly (ADP-ribose) polymerase (PARP), ${\beta}-catenin$ and phospholipase $(PLC)-{\gamma}1$ protein. Furthermore, caspase-3 inhibitor, z-DEVD-fmk, significantly inhibited WECM-induced apoptosis demonstrating the important role of caspase-3 in the observed cytotoxic effect. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of C. militaris.

• Tuberculosis and Respiratory Diseases
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• v.56 no.4
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• pp.381-392
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• 2004

Arsenic trioxide($As_2O_3$) was introduced into the treatment of refractory or relapsed acute promyelocytic Ieukemia. Some investigators have reported that arsenic trioxide had induced apoptosis in a variety of solid human tumor cell lines, including non-small cell lung cancer. Non-steroidal anti-inflammatory drugs(NSAIDs) are powerful chemopreventive agents for gastrointestinal cancers and the growth of established tumors are reduced by inducing apoptosis. It's also reported that NSAIDs enhanced tumor response to chemotherapeutic drugs or radiation. In this study, we aimed to determine whether combination of arsenic trioxide with sulindac augmented its apoptotic potential in NCI-H157 human lung cancer cells. The human lung cancer cell line NCI-H157 was treated with arsenic trioxide and sulindac. Cell viability was measured by the MTT assay. Apoptosis was measured by nuclear staining and flow cytometric analysis. The catalytic activity of the caspase families were measured by the fluorogenic cleavage of biosubstrates. The western blotting were also performed to define the mechanical basis of apoptosis. Combination treatment of arsenic trioxide and sulindac decreased the viability of NCI-H157 human lung cancer cells in a dose-dependent manner. The catalytic activity of caspase-3, 8 and 9 proteases were increased after combination treatment. Consistently PARP was cleaved from 116kDa to 85kDa fragments, and the expression of ICAD was decreased by time-dependent manner. Also combination treatment increased the expression of Fas and Fas/L. Combination therapy of arsenic trioxide with sulindac augments cell death and induces apoptosis via the activation of caspase cascade in NCI-H157 human lung carcinoma cells.