• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2129-2144
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• 2015

Programmed cell death (PCD) or apoptosis is a mechanism which is crucial for all multicellular organisms to control cell proliferation and maintain tissue homeostasis as well as eliminate harmful or unnecessary cells from an organism. Defects in the physiological mechanisms of apoptosis may contribute to different human diseases like cancer. Identification of the mechanisms of apoptosis and its effector proteins as well as the genes responsible for apoptosis has provided a new opportunity to discover and develop novel agents that can increase the sensitivity of cancer cells to undergo apoptosis or reset their apoptotic threshold. These novel targeted therapies include those targeting anti-apoptotic Bcl-2 family members, p53, the extrinsic pathway, FLICE-inhibitory protein (c-FLIP), inhibitor of apoptosis (IAP) proteins, and the caspases. In recent years a number of these novel agents have been assessed in preclinical and clinical trials. In this review, we introduce some of the key regulatory molecules that control the apoptotic pathways, extrinsic and intrinsic death receptors, discuss how defects in apoptotic pathways contribute to cancer, and list several agents being developed to target apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3857-3862
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• 2012

A total of 96 cases of invasive breast ductal carcinoma were examined for immunohistochemical expression of Bax and Bcl-2 in the epithelial tumor cells and endothelial cells of the blood vessels. We also investigated the association between both proteins in the epithelium in relation to tumor characteristics such as tumor size, grade, lymph node involvement, microvessel density (MVD), hormonal receptors expression and c-erbB-2 overexpression. Bax expression showed a significant association between tumor and endothelial cells (p<0.001) while Bcl-2 expression in tumor cells was inversely associated with that in the endothelial cells (p<0.001). Expression of Bcl-2 in tumor cells was strongly associated with expression of estrogen and progesterone receptors (p=0.003 and p=0.004, respectively). In addition, intratumoral MVD was significantly higher than peritumoral MVD (p<0.001) but not associated with Bax or Bcl-2 expression and other tumor characteristics. We concluded that the number of endothelial cells undergoing apoptosis was in direct linkage with the number of apoptotic tumor cells. Anti-apoptotic activity of the surviving tumor cells appears to propagate cancer progression and this was influenced by the hormonal status of the cells. Tumor angiogenesis was especially promoted in the intratumoral region and angiogenesis was independent of anti-apoptotic activity.

• Journal of Life Science
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• v.21 no.12
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• pp.1678-1688
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• 2011

The apoptogenic effect of p-coumaric acid, a phenolic acid found in various edible plants, on human acute leukemia Jurkat T cells was investigated. Exposure of Jurkat T cells to p-coumaric acid (50-$150{\mu}M$) caused cytotoxicity and TdT-mediated dUTP nick-end labeling (TUNEL)-positive apoptotic DNA fragmentation along with Bak activation, ${\Delta}{\psi}m$ loss, activation of caspase-9, -3, -7, and -8, and PARP degradation in a dose-dependent manner. However,these apoptotic events were completely abrogated in Jurkat T cells overexpressing Bcl-2.Under these conditions, necrosis was not accompanied. Pretreatment of the cells with the pan-caspase inhibitor (z-VAD-fmk) could prevent p-coumaric acid-induced sub-$G_1$ peak representing apoptotic cells, whereas it failed to block ${\Delta}{\psi}m$ loss, indicating that the activation of caspase cascade was prerequisite for p-coumaric acid-induced apoptosis as a downstream event of ${\Delta}{\psi}m$ loss. FADD- and caspase-8-positive wild-type Jurkat T cell clone A3, FADD-deficient Jurkat T cell clone I2.1, and caspase-8-deficient Jurkat T cell clone I9.2 exhibited similar susceptibilities to the cytotoxicity of p-coumaric acid, excluding an involvement of Fas/FasL system in triggering the apoptosis. The apoptogenic activity of p-coumaric acid is more potent in malignant Jurkat T cells than in normal human peripheral T cells. Together, these results demonstrated that p-coumaric acid-induced apoptogenic activity in Jurkat T cellswas mediated by Bak activation, ${\Delta}{\psi}m$ loss, and subsequent activation of multiple caspases such as caspase-9, -3, -7, and-8, and PARP degradation, which could be regulated by anti-apoptotic protein Bcl-2.

• Toxicological Research
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• v.22 no.1
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• pp.31-37
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• 2006

It was previously found that melittin inhibited $NF-{\kappa}B$ activity by reacting with signal molecules of $NF-{\kappa}B$ which is critical contributor in cancer cell growth by induction of apoptotic cell death. We here investigated whether melittin inhibits cell growth of human prostate cancer cells through induction of apoptotic cell death, and the possible signal pathways. Melittin ($0{\sim}1\;{\mu}g/ml$) inhibited prostate cancer cell growth in a dose dependent manner. Conversely related to the growth inhibitory effect, melittin increased the induction of apoptotic cell death in a dose dependent manner. Melittin also inhibited DNA binding activity of $NF-{\kappa}B$, an anti-apoptotic transcriptional factor. Consistent with the induction of apoptotic cell death and inhibition of $NF-{\kappa}B$, melittin increased the expression of pro-apoptotic proteins caspase-3, and Bax but down-regulated anti-apoptotic protein Bcl-2. These findings suggest that melittin could inhibit prostate cancer cell growth, and this effect may be related with the induction of apoptotic cell death via inactivation of $NF-{\kappa}B$.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.679-686
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• 2003

Purpose : Ataxia telangiectasia mutated(ATM) is involved in DNA damage responses at different cell cycle checkpoints, and signalling pathways associated with regulation of apoptosis in response to ionizing radiation(IR). However, the signaling pathway that underlies IR-induced apoptosis in ATM cells has remained unknown. The purpose of this study was, therefore, to investigate the apoptotic pathway that underlies IR-induced apoptosis in a CT-26 cells expressing dominant negative ATM (DN-ATM). Methods : We generated a replication-deficient recombinant adenovirus encoding the DN-ATM(Ad/DN-ATM) or control adenovirus encoding no transgene(Ad/GFP) and infected adenovirus to CT-26 cells. After infection, we examined apoptosis and apoptotic pathway by [$^3H$]-thymidine assay, DNA fragmentation, and Western immunoblot analysis. Results : DN-ATM gene served as the creation of AT phenotype in a CT-26 cells as revealed by decreased cell proliferations following IR. In addition, IR-induced apoptosis was regulated through the reduced levels of the anti-apoptotic protein Bcl-2, the increased levels of the apoptotic protein Bax, and the activation of caspase-9, caspase-3, and PARP. Conclusion : These results indicate that the pathway of IR-induced apoptosis in CT-26 cells expressing DN-ATM is mediated by mitochondrial signaling pathway involving the activation of caspase 9, caspase 3, and PARP.

• Journal of Acupuncture Research
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• v.34 no.1
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• pp.1-9
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• 2017

Objectives : We investigated the synergistic effects of bee venom (BV) and natural killer (NK) cells on B16F10 melanoma cell apoptosis mediated by IL-4. Methods : We performed a cell viability assay to determine whether BV can enhance the inhibitory effect of NK-92MI cells on the growth of B16F10 melanoma cells, and western blot analysis to detect changes in the expression of IL-4, $IL-4R{\alpha}$, and other apoptosis-related proteins. EMSA was performed to observe the activity of STAT6. To confirm that the inhibitory effect of BV and NK cells was mediated by IL-4, the above tests were repeated after IL-4 silencing by siRNA (50 nM). Results : B16F10 melanoma cells co-cultured with NK-92MI cells and simultaneously treated by BV ($5{\mu}g/ml$) showed a higher degree of proliferation inhibition than when treated by BV ($5{\mu}g/ml$) alone or co-cultured with NK-92MI cells alone. Expression of IL-4, $IL-4R{\alpha}$, and that of other pro-apoptotic proteins was also enhanced after co-culture with NK-92MI cells and simultaneous treatment with BV ($5{\mu}g/ml$). Furthermore, the expression of anti-apoptotic bcl-2 decreased, and the activity of STAT6, as well as the expression of STAT6 and p-STAT6 were enhanced. IL-4 silencing siRNA (50 nM) in B16F10 cells, the effects of BV treatment and NK-92MI co-culture were reversed. Conclusion : These results suggest that BV could be an effective alternative therapy for malignant melanoma by enhancing the cytotoxic and apoptotic effect of NK cells through an IL-4-mediated pathway.

• International Journal of Oral Biology
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• v.32 no.3
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• pp.113-118
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• 2007

Treatment of oral cancers with chemotherapeutic agents become evaluated as an effective method to reduce cancer cell proliferation. Anti-proliferative and anti-oral cancer activities of momordin I on oral cancer cells were evaluated in this study. Momordin I was originally purified from a natural product, Ampelopsis radix and showed the antiproliferative activity against oral carcinoma, KB cells. Obtained $IC_{50}$ value was approximately $10.4{\mu}g/ml$. Time-and dose-dependent chromosomal DNA fragmentations were observed in momordin I-treated KB cells. Flow cytometry analysis showed time-dependent apoptotic cell appearance after treatment of momordin I. Approximately 18.6% apoptotic cells were observed at 72 hours after $20{\mu}g/ml$ of momordin I treatment. These observation were consistent with the results obtained in DNA fragmentation analysis. These data suggest that momordin I has anti-proliferative effect and induces cell death in KB cells through apoptosis.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.150-154
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• 2008

Butein is a one of polyphenolic compound widely available in numerous plants. It has broad biological activities including antioxidant and anti-inflammatory activities, which contributed to its protective effects against cancer. Evidences that butein influence proliferation of tumor cells make it important to determine how butein affects cell death of various cancers. In this study, we show that butein, a phenolic compound, induces apoptosis in human T lymphoma jurkat cells. We found that treatment of cells with butein increased apoptosis in a dose- and time- dependent manner as determined by staining cells with Annexin V and 7AAD. There was no significant apoptotic cell death when normal lymphocytes and monocytes from healthy donor were treated with butein. We also found caspase-3 activity was increased during butein-induced apoptosis. The buteininduced apoptotic cell death was blocked by the treatment of cells with caspase-3 inhibitor. These results indicate that butein has the potential to provide an effective strategy against cancer with the advantage of being widely avalible.

• YAKHAK HOEJI
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• v.57 no.1
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• pp.18-23
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• 2013

The objective of this study is to evaluate the synergic effects of combined treatment with taurine and cisplatin in human breast cancer, MCF-7 cells. For this study, MCF-7 cells were treated with taurine (5, 10, and 20 mM) and cisplatin (0.5 ${\mu}M$) for 48 and 72 hrs. Co-treatment of cisplatin with taurine decreased cell proliferation more compared with cisplatin alone. Reduced cell proliferation was caused by apoptosis. Therefore we investigated the apoptotic cells. After treatment of cisplatin and taurine, apoptotic cells were slightly increased. Apoptosis-related proteins, cleaved caspases and cytochrome c were increased. The present study suggests that combination treatment of cisplatin with taurine enhance anticancer activity of cisplatin in MCF-7 cells.

• Biomedical Science Letters
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• v.24 no.2
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• pp.134-137
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• 2018

S100A8 and S100A9 are involved in pathogenesis of cancer by induction or inhibition of cancer as well as inflammation. In this study, we investigated the association of S100A8 and S100A9 with pathogenesis of leukemia using human monocytic leukemia cells, THP-1. The expression of TLR4, which is a known receptor of S100A8 and S100A9, was examined by using flow cytometry and Western blotting. THP-1 cells have high surface and cytosol expression of TLR4. S100A8 and S100A9 suppressed the cell survival, and this suppression was found to be associated with apoptosis because they increased the number of apoptotic cells in a dose- and a time-dependent manners. However, S100A8 and S100A9 had no effect on the survival and apoptosis of monocytes isolated from the peripheral blood. We next examined the apoptotic effect of lipopolysaccharide (LPS) and monophosphoryl lipid A (MPLA), which are other ligands of TLR4, in THP-1 cells. Lipopolysaccharide had no effect on cell survival, but MPLA is effective on the cell apoptosis. These results suggest that S100A8 and S100A9 may regulate leukemia cell survival via TLR4, which is an essential receptor in the pro-apoptotic mechanism induced by S100A8 and S100A9. These findings may shed light on development of a possible therapeutic drug for leukemia treatment.