• Journal of Life Science
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• v.21 no.8
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• pp.1109-1119
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• 2011

In the present study, the pro-apoptotic effects of methanol extract of Prunus mume fruits (MEPM) in human leukemia U937 cells were investigated. It was found that exposure to MEPM resulted in growth inhibition in a concentration-dependent manner by inducing apoptosis. The induction of apoptotic cell death in U937 cells by MEPM was correlated with a down-regulation of inhibitor of apoptosis protein (IAP) family, such as X-linked inhibitor of apoptosis protein (XIAP) and survivin, anti-apoptotic Bcl-2, up-regulation of FasL and cleavage of Bid. MEPM treatment also induced the proteolytic activation of caspase-3, caspase-8 and caspase-9, and degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase (PARP) and ${\beta}$-catenin. In addition, apoptotic cell death induced by MEPM was significantly inhibited by z-DEVD-fmk, a caspase-3 specific inhibitor, which demonstrates the important role of caspase-3 in the apoptotic process by MEPM in U937 cells. Taken together, these findings suggest that P. mume extracts may be a potential chemotherapeutic agent for the control of human leukemia cells and further studies will be needed to identify the active compounds.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3293-3299
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• 2015

Background: Arm protein lost in epithelial cancers, on chromosome X (ALEX) is a novel subgroup within the armadillo (ARM) family, which has one or two ARM repeat domains as opposed to more than six-thirteen repeats in the classical Armadillo family members. Materials and Methods: In the study, we explore the biological functions of ALEX1 in breast cancer cells. Overexpression of ALEX1 and silencing of ALEX1 were performed with SK-BR3 and MCF-7 cell lines. Cell proliferation and colony formation assays, along with flow cytometry, were carried out to evaluate the roles of ALEX1. Results: ALEX1 overexpression in SK-BR3 breast cancer cells inhibited proliferation and induced apoptosis. Furthermore, depletion of ALEX1 in MCF-7 breast cancer cells increased proliferation and inhibited apoptosis. Additional analyses demonstrated that the overexpression of ALEX1 activated the intrinsic apoptosis cascades through up-regulating the expression of Bax, cytosol cytochrome c, active caspase-9 and active caspase-3 and down-regulating the levels of Bcl-2 and mitochondria cytochrome c. Simultaneouly, silencing of ALEX1 inhibited intrinsic apoptosis cascades through down-regulating the expression of Bax, cytosol cytochrome c, active caspase-9, and active caspase-3 and up-regulating the level of Bcl-2 and mitochondria cytochrome c. Conclusions: Our data suggest that ALEX1 as a crucial tumor suppressor gene has been involved in cell proliferation and apoptosis in breast cancer, which may serve as a novel candidate therapeutic target.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.413-424
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• 2013

Korean Red Ginseng extract (KRGE) is a traditional herbal medicine utilized to prevent endothelium dysfunction in the cardiovascular system; however, its underlying mechanism has not been clearly elucidated. We here examined the pharmacological effect and molecular mechanism of KRGE on apoptosis of human umbilical vein endothelial cells (HUVECs) in a serum-deprived apoptosis model. KRGE protected HUVECs from serum-deprived apoptosis by inhibiting mitochondrial cytochrome c release and caspase-9/-3 activation. This protective effect was significantly higher than that of American ginseng extract. KRGE treatment increased antiapoptotic Bcl-2 and Bcl-$X_L$ protein expression and Akt-dependent Bad phosphorylation. Moreover, KRGE prevented serum deprivation-induced subcellular redistribution of these proteins between the mitochondrion and the cytosol, resulting in suppression of mitochondrial cytochrome c release. In addition, KRGE increased nitric oxide (NO) production via Akt-dependent activation of endothelial NO synthase (eNOS), as well as inhibited caspase-9/-3 activities. These increases were reversed by co-treatment of cells with inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) and pre-incubation of cell lysates in dithiothreitol, indicating KRGE induces NO-mediated caspase modification. Indeed, KRGE inhibited caspase-3 activity via S-nitrosylation. These findings suggest that KRGE prevents serum deprivation-induced HUVEC apoptosis via increased Bcl-2 and Bcl-$X_L$ protein expression, PI3K/Akt-dependent Bad phosphorylation, and eNOS/NO-mediated S-nitrosylation of caspases. The cytoprotective property of KRGE may be valuable for developing new pharmaceutical means that limit endothelial cell death induced during the pathogenesis of vascular diseases.

• Journal of Life Science
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• v.31 no.10
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• pp.954-959
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• 2021

Apoptosis is an important mechanism that regulates cellular populations to maintain homeostasis, and the caspases, a family of cysteine proteases, are key mediators of the apoptosis pathway. Caspase-8 is an initiator caspase of the extrinsic apoptotic pathway, which is initiated by extracellular stimuli. Caspase-8 have two conserved domains, N-terminal tandem death effector domains (DED) and C-terminal two catalytic domain, which are important for this extrinsic apoptosis pathway. In extrinsic apoptosis pathway, death receptors which members of TNF superfamily are activated by binding of death receptor specific ligands from cell outside. After the activated death receptors recruit adaptor protein Fas-associated death domain protein (FADD), death domains (DD) of death receptor and FADD bind to each other and FADD combined with death receptor recruits procaspase-8, a precursor form of caspase-8. The DED of FADD and procaspase-8 bind to one another and FADD-bound procaspase-8 is activated by cleavage of the prodomain. This death receptor-FADD-caspase-8 complex called death inducing signaling complex (DISC). Cellular FLICE-inhibitory proteins (c-FLIPs) regulate caspase-8 activation by acting both anti- and pro-apoptotically, and caspase-8 activation initiates the activation of executioner caspases such as caspase-3. Finally activated executioner caspases complete the apoptosis by acting critically DNA degradation, nuclear condensation, plasma membrane blebbing, and the proteolysis of certain caspase substrates.

• Development and Reproduction
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• v.15 no.2
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• pp.113-120
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• 2011

BCL-2 family essential proteins to play a pivotal role to perform in apoptosis signaling pathways and essential proteins for the regulation of cell death. BCL2L10 protein is a member of BCL-2 family and it regulates both anti-apoptotic and pro-apoptotic function of specific tissue or cell line. BCL2L10 of function and expression is not reported in ovary cell lines. In this study we reported that BCL2L10 were significant expression of KGN cell line. Ectopic expression of BCL2L10 induced cell death, and its cells killing effect was blocked by pan-caspase inhibitor of the Z-VAD-fmk. Ectopic expression of BCL2L10 protein led to the activation of caspase 9 and caspase 3, suggesting apoptotic cell death, and confocal microscopic analyses showed that BCL2L10 was partially localized in mitochondria. Thus, we provide a novel function of BCL2L10 in KGN cells, which was involved in the intrinsic cell death pathway.

• Journal of Life Science
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• v.17 no.11
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• pp.1596-1600
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• 2007

Bee venom is used to treat inflammatory diseases in Korean traditional medicine and has been known to inhibit proliferation and induce apoptosis in cancer cells. However, the molecular mechanisms involved in bee venom-induced apoptosis are still uncharacterized in human lung cancer cells. In the present study, we investigated the effects of bee venom on the apoptosis of A549 human lung epithelial cancer cells. Treatment of bee venom inhibited the cell viability and induced apoptosis in a concentration-dependent manner as measured by hemocytometer counts, fluorescence microscopy and flow cytometry analysis. Bee venom-induced apoptosis in A549 cells was associated with a marked inhibition of anti-apoptotic Bcl-2 expression without significant changes in the levels of Bax and Bcl-xL. Bee venom treatment also inhibited the levels of IAP family members such as cIAP-1 and cIAP-2 and induced the proteolytic activation of caspase-3 and caspase-9. Although further studies are needed, the present results suggest that apoptotic signals evoked by bee vemon in A549 cancer cells may converge caspases activation through a down-regulation of Bcl-2 rather than an up-regulation of Bax. These findings provide important insights into the possible molecular mechanisms of the anti-cancer activity of bee vemon in human cancer cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.187-192
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• 2006

Herbal medicines have been utilized to treat a variety of diseases, including cancer. Several species of the family rubiaceae have been reported to have antitumor activity. In this study, we report the cytotoxicity and antitumor activity exhibited dy the methanol extracts prepared from Rubia radix (RRME), Uncaria gambir (UGME) and Oldenlandia diffusa (ODME) (family: Rubiaceae) against human promyleloid leukemia cell line, HL-60. The cytotoxicity of RRME (2~20 ${\mu}g/ml$), UGME (20~200 ${\mu}g/ml$) and ODME (20~200 ${\mu}g/ml$) were assessed dy the MTT reduction assay. IC50 values for RRME, UGME and ODME were 11.0, 99.5 and 106.1 ${\mu}g/ml$, respectively. When the HL-60 cells were treated with RRME (10 ${\mu}g/ml$), UGME (120 ${\mu}g/ml$) and ODME (140 ${\mu}g/ml$) for 24 h, several apoptotic characteristics such as DNA fragmentation and morphologic changes were observed. Furthermore, flow cytometric analysis was peformed to determine the percent of apoptotic cells. The poupulation of sub-G1 hypodiploid cells was increased 37.49% in RRME treatment, 12.49% in UGME treatment and 7.21% in ODME treatment compared with untreated control cells (2.64%). To further confirm apoptotic cell death, we assayed caspase-3, -8 and -9 activities in RRME, UGME and ODME-treated cells. After treatment of RRME, UGME and ODME for 12 h, caspase-3, -8 and -9 activities significantly increased.compared to untreated control cells. These results show that RRME, UGME and ODME induced apoptotic cell death in HL-60 cells and may have a possibility of potential antitumor activities.

• 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.

• Journal of Nutrition and Health
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• v.35 no.1
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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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.216-224
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• 2011

Capsosiphon fulvescens is well-known green sea algae that, in recent years, has been proposed as a potential anticancer drug. In this study, we found that C. fulvescens glycoprotein (Cf-GP) had pro-apoptotic effects on human gastric carcinoma cells. By SDS-PAGE, we confirmed that C. fulvescens extract contained a glycoprotein. Using H33342 staining, we found that the Cf-GP caused cell death in a does-dependent manner, while an MTS assay showed decreased cellular viability due to induction of apoptosis. To determine the effect of Cf-GP on apoptosis-related cellular events, cells were treated with Cf-GP and the expression of several apoptosis-related protein was determined by Western blotting. Our results indicate that Cf-GP activated both a caspase cascade and PARP, which is a substrate of caspase-3, caspase-8 and the Bcl-2 family proteins. In addition, we assessed caspase-3, and -8 activation and annexin V staining. Our results revealed a cell cycle arrest, itself leading to an increased percentage of sub-G1 cells. Our findings indicate that Cf-GP may be a source of bio-functional material with therapeutic effects on human gastrointestinal cancer.