• Journal of Life Science
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• v.21 no.11
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• pp.1549-1557
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• 2011

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis in many types of transformed cells; however, some human hepatocellular carcinoma cells are particularly resistant to the effects of TRAIL. Although genistein, a natural isoflavonoid phytoestrogen, has been shown to have pro-apoptotic activity against human cancer cell lines, little is known about the mechanism of genistein in terms of TRAIL-induced apoptosis. In the present study, it was investigated whether or not combined treatment with genistein and TRAIL synergistically induced apoptosis in Hep3B hepatocarcinoma cells. Results indicate that treatment with TRAIL in combination with nontoxic concentrations of genistein sensitized TRAIL-resistant Hep3B cells to TRAIL-induced apoptosis, which was associated with mitochondrial dysfunction. Further, the inhibition of p38 mitogen-activated protein kinase (MAPK) activation markedly decreased genistein and TRAIL-induced cell viability and apoptosis by enhanced truncation of Bid, increase of pro-apoptotic Bax, decrease of anti-apoptotic Bcl-2, and release of cytochrome c from mitochondria to cytoplasm. Activation of caspases and degradation of poly (ADP-ribose) polymerase induced by the combined treatment was also markedly increased by the inhibition of p38 MAPK, through the mitochondrial amplification step. In conclusion, our data suggest that genistein sensitizes TRAIL-induced-apoptosis via p38 MAPK-dependent pathway.

• Journal of Life Science
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• v.27 no.5
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• pp.545-552
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• 2017

Julbernardia globiflora, a tropical African tree widespread in Miombo woodland, has been used in folk medicine for the treatment of depression and stomach problems. However, the antioxidative and anticancer activities of J. globiflora remain unclear. The objective of this study is to evaluate the antioxidative and anticancer effects of methanol extract of J. globiflora (MEJG) and the molecular mechanism of its anticancer activity in human colon carcinoma HT29 cells. MEJG exhibited significant antioxidative effect with an $IC_{50}$ (concentration at 50% inhibition) value of $1.23{\mu}g/ml$ measuring by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and inhibited cell proliferation in a dose-dependent manner in HT29 cells. We found that MEJG induced apoptosis of HT29 cells with the increase of apoptotic cells and apoptotic bodies using Annexin V staining and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively. The MEJG treatment showed the increase of Fas, a death receptor, and Bax, a pro-apoptotic protein, and the decrease of Bcl-2, an anti-apoptotic protein, resulting in the release of cytochrome c from the mitochondria into the cytosol and activation of caspase-3, -8 and -9. The apoptotic effects of MEJG were confirmed by cleavage of poly (ADP-ribose) polymerase (PARP). Collectively, these results suggest that MEJG may exert the anticancer effect in HT29 cells by inducing apoptosis via both the intrinsic and extrinsic pathways.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.714-720
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• 2008

Cordyceps militaris is a medicinal fungus which has been used for patient suffering from cancer in Oriental medicine. It was previously reported that C. militaris extracts are capable of inhibiting tumor growth and inducing apoptosis; however, the anti-poliferative effects of human cancer cells have been poorly understood. In this study, to elucidate the anti-cancer mechanisms of human cancer cells by treatment with aqueous extract of C. militaris (AECM), we investigated the anti-proliferative effects of AECM in human hepatocarcinoma Hep3B cells. AECM treatment inhibited the growth of Hep3B cells and induced the apoptotic cell death in a concentration-dependent manner such as formation of apoptotic bodies and increased populations of apoptotic-sub G1 phase. The induction of apoptosis by AECM was connected with a proteolytic activation of caspase-3 and caspase-8. and concomitant degradation of poly (ADP-ribose) polymerase (PARP) and ${\beta}$-catenin proteins. Furthermore, caspase-3 inhibitor, z-DEVD-fmk, significantly inhibited AECM-induced apoptosis demonstrating the important role of caspase-3 in the bserved cytotoxic effect. Taken together, these findings suggest that AECM-induced inhibition of human hepatocarcinoma cell proliferation is associated with the induction of apoptotic cell death via activation of caspase-3 and C. militaris may have therapeutic potential in human cancer.

• Tuberculosis and Respiratory Diseases
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• v.76 no.3
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• pp.114-119
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• 2014

Background: Epigallocatechin-3-gallate (EGCG), a major biologically active component of green tea, has anti-cancer activity in human and animal models. We investigated the schedule-dependent effect of EGCG and paclitaxel on growth of NCI-H460 non-small cell lung cancer cells. Methods: To investigate the combined effect of EGCG (E) and paclitaxel (P), combination indices (CIs) were calculated, and cell cycle analysis was performed. For the effect on cell apoptosis, western blot analysis was also performed. Results: CI analysis demonstrated that both concurrent and sequential E ${\rightarrow}$ P treatments had antagonistic effects (CIs >1.0), but sequential P ${\rightarrow}$ E had synergistic effects (CIs <1.0), on the growth inhibition of NCI-H460 cells. In the cell cycle analysis, although paclitaxel induced $G_2/M$ cell cycle arrest and increased the sub-G1 fraction, concurrent EGCG and paclitaxel treatments did not have any additive or synergistic effects compared with the paclitaxel treatment alone. However, western blot analysis demonstrated that sequential P ${\rightarrow}$ E treatment decreased the expression of Bcl-2 and procaspase-3 and increased poly(ADP-ribose) polymerase (PARP) cleavage; while minimal effects were seen with concurrent or sequential E ${\rightarrow}$ P treatments. Conclusion: Concurrent or sequential E ${\rightarrow}$ P treatment had opposite effects to P ${\rightarrow}$ E treatment, where P ${\rightarrow}$ E treatment showed a synergistic effect on growth inhibition of NCI-H460 cells by inducing apoptosis. Thus, the efficacy of EGCG and paclitaxel combination treatment seems to be schedule-dependent.

• Journal of dental hygiene science
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• v.18 no.2
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• pp.76-84
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• 2018

Wet wipes are being increasingly used because of their convenience. Particularly, oral wet wipes are useful for regular cleaning of a baby's mouth after birth. Therefore, the consumption of oral wet wipes has increased over the past few years and a variety of products are commercially available. However, product information on safety is not sufficiently provided and still raises doubts regarding adverse effects. To confirm the safety of wet wipes as an oral hygiene item and provide information for their use, we investigated the cytotoxicity of oral wet wipes and verified the underlying mechanism. The anti-bacterial effect of oral wet wipes was analyzed using the disk diffusion method. The cytotoxic effects of oral wet wipes were observed based on morphological changes using microscopy and determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in gingival epithelial cells and gingival fibroblasts. Evaluation of apoptosis by oral wet wipes was explored using propidium iodide flow cytometric analysis and a terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) assay. Apoptosis-related molecules were also analyzed using western blotting. Five types of oral wet wipes were tested, and two products from Fisher-Price and Dr. Kennedy revealed strong cytotoxic effects on gingiva epithelial cells and gingiva fibroblasts, although they also showed intense anti-bacterial effects on oral bacteria. Cell cycle arrest in the G2/M phase and apoptosis were observed based on treatment of extracts from Fisher-Price and Dr. KENNEDY. Relatively high TUNEL levels, reduction of proliferating cell nuclear antigen and cyclin-dependent kinase 4 expression, and fragmentation of poly (ADP-ribose) polymerase were also elucidated. These results suggest that commercial oral wet wipes could exert cytotoxic influences on oral tissue, although there are anti-bacterial effects, and careful attention is required, especially for infants and toddlers.

• Journal of Life Science
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• v.25 no.2
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• pp.249-255
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• 2015

Schisandrae fructus [Schizandra chinensis (Turcz.) Baillon] is a medicinal herb widely used for treating various inflammatory and immune diseases in East Asian countries. The Schisandrae Semen essential oil (SSeo) from this plant has pharmacological activities, including antioxidant, antimicrobial, and antitumoral activities. Nevertheless, the biological activities and underlying molecular mechanisms of the potential anti-cancer effects of this oil remain unclear. In the present study, we investigated the potential inhibition of apoptosis signaling pathways by SSeo in human leukemia U937 cells and evaluated the underlying molecular mechanism. Exposure to SSeo resulted in a concentration-dependent growth inhibition due to apoptosis, which was verified by DNA fragmentation, the presence of apoptotic bodies, and an increase in the sub-G1 ratio. Induction of apoptotic cell death by SSeo was correlated with the down-regulation of members of the inhibitor of apoptosis protein (IAP) family (including X-linked inhibitor of apoptosis protein (XIAP), cIAP-1, and surviving) and anti-apoptotic Bcl-2, and with up-regulation of death receptor (DR) 4 and DR5, depending on dosage. SSeo treatment also induced Bid truncation, mitochondrial dysfunction, proteolytic activation of caspase-3, -8 and -9, and concomitant degradation of activated caspase-3 target proteins such as poly (ADP-ribose) polymerase. Taken together, these findings suggest that SSeo may be a potential chemotherapeutic agent for use in the control of human leukemia cells. Further studies are needed to identify its active compounds.

• Journal of Life Science
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• v.18 no.3
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• pp.336-343
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• 2008

Histone deacetylases (HDACs) inhibitors have emerged as the accessory therapeutic agents for various human cancers, since they can block the activity of specific HDACs, restore the expression of some tumor suppressor genes and induce cell differentiation, cell cycle arrest and apoptosis in vitro and in vivo. In the present study, we investigated that the effect of trichostatin A (TSA), an HDAC inhibitor, on the cell growth and apoptosis, and its effect on the nuclear factor-kappaB $(NF-{\kappa}B)$ activity in 267B1 human prostate epithelial cells. Exposure of 267B1 cells to TSA resulted in growth inhibition and apoptosis induction in and dose-dependent manners as measured by fluorescence microscopy, agarose gel electrophoresis and flow cytometry analysis. TSA treatment inhibited the levels of IAP family members such as c-IAP-1 and c-IAP-2 and induced the proteolytic activation of caspase-3, -8 and -9, which were associated with concomitant degradation of poly (ADP-ribose)-polymerase, ${\beta}-catenin$ and laminin B proteins. The increase in apoptosis by TSA was connected with the translocation of $NF-{\kappa}B$ from cytosol to nucleus, increase of the DNA binding as well as promoter activity of $NF-{\kappa}B$, and degradation of cytosolic inhibitor of KappaB $(I{\kappa}B)-{\alpha}$ protein. We therefore concluded that TSA demonstrated anti-proliferative and apoptosis-inducing effects on 267B1 cells in vitro, and that the activation of caspases and $NF-{\kappa}B$ may play important roles in its mechanism of action. Although further studies are needed, these findings provided important insights into the possible molecular mechanisms of the anti-cancer activity of TSA.

• Journal of Life Science
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• v.23 no.4
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• pp.518-528
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• 2013

Scutellaria baicalensis, belonging to the family Labiatae, is widely distributed in Korea, China, Mongolia, and eastern Siberia. It has been used in traditional medicine for various diseases, such as dysentery, pyrexia, jaundice, and carbuncles. In addition, S. baicalensis is reported to possess various beneficial pharmacological activities, including anti-inflammatory, antidiabetic, antiviral, antihypertension, antioxidant, and anticancer effects. However, the molecular mechanisms of its anticancer activity have not been clearly elucidated. In the present study, we investigated the proapoptotic effects of ethanol extract of S. baicalensis (EESB) on human renal cell carcinoma Caki-1 cells. The anti-proliferative activity of EESB was associated with apoptosis induction, which was associated with the up-regulation of death receptor 4, the Fas ligand, and Bax and the down-regulation of Bid, XIAP, and cIAP-1 proteins. EESB treatment also induced mitochondrial dysfunction, proteolytic activation of caspase-3, -8, and -9 and degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase, ${\beta}$-catenin, and phospholipase C-${\gamma}1$. However, pretreatment of a pan-caspase inhibitor, z-VAD-fmk, significantly attenuated the EESB-induced apoptosis. Taken together, these findings suggest that EESB may be a potential chemotherapeutic agent. Further studies will be needed to identify the active compounds that confer the anticancer activity of S. baicalensis.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.287-294
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• 2016

The effect of kaempferol (3,5,7,4-tetrahydroxyflavone), a flavonoid compound that was identified in barnyard millet (Echinochloa crus-galli var. frumentacea) grains, on G₂-checkpoint and apoptotic pathways was investigated in human acute leukemia Jurkat T cell clones stably transfected with an empty vector (J/Neo) or a Bcl-xL expression vector (J/Bcl-xL). Exposure of J/Neo cells to kaempeferol caused cytotoxicity and activation of the ATM/ATR-Chk1/Chk2 pathway, activating the phosphorylation of p53 (Ser-15), inhibitory phosphorylation of Cdc25C (Ser-216), and inactivation of cyclin-dependent kinase 1 (Cdk1), with resultant G₂-arrest of the cell cycle. Under these conditions, apoptotic events, including upregulation of Bak and PUMA levels, Bak activation, mitochondrial membrane potential (Δψm) loss, activation of caspase-9, -8, and -3, anti-poly (ADP-ribose) polymerase (PARP) cleavage, and accumulation of apoptotic sub-G₁ cells, were induced without accompanying necrosis. However, these apoptotic events, except for upregulation of Bak and PUMA levels, were completely abrogated in J/Bcl-xL cells overexpressing Bcl-xL, suggesting that the G₂-arrest and the Bcl-xL-sensitive mitochondrial apoptotic events were induced, in parallel, as downstream events of the DNA-damage-mediated G₂-checkpoint activation. Together these results demonstrate that kaempferol-mediated antitumor activity toward Jurkat T cells was attributable to G₂-checkpoint activation, which caused not only G₂-arrest of the cell cycle but also activating phosphorylation of p53 (Ser-15) and subsequent induction of mitochondria-dependent apoptotic events, including Bak and PUMA upregulation, Bak activation, Δψm loss, and caspase cascade activation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.649-659
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• 2011

To examine the anti-cancer effects of Lepidium virginicum L., the anti-proliferative and pro-apoptotic effects of a water extract of L. virginicum leaves (WELVL) and of L. virginicum roots (WELVR) were investigated in HCT116 human colon carcinoma cells. The treatment of HCT116 cells with WELVL and WELVR resulted in the inhibition of growth and morphological changes in a concentration-dependent manner by inducing apoptosis. The growth inhibition and apoptosis induction by WELVR was stronger than that of WELVL thus, we determined that WELVR was the more optimal extract for this study. The increased apoptotic events in HCT116 cells caused by WELVR were associated with an up-regulation of Fas ligand, Bax, and Bad expression, a down-regulation of Bcl-2, Bcl-$_XL$, and Bid expression, and a decrease in the mitochondrial membrane potential (MMP, ${\Delta}{\psi}m$). WELVR treatment induced the proteolytic activation of caspase-3, -8, and -9, and the degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase (PARP), ${\beta}$-catenin, and phospholipase C-${\gamma}1$ (PLC-${\gamma}1$). In addition, apoptotic cell death induced by WELVR was correlated with a down-regulation of inhibitors of the apoptosis protein (IAP) family, such as the X-linked inhibitor of apoptosis protein (XIAP), cIAP-1, and cIAP-2. These findings suggest that the WELVR-induced inhibition of cell proliferation is associated with the induction of apoptotic cell death. WELVR may be a potential chemotherapeutic agent for the control of HCT116 human colon carcinoma cells.