• Journal of Gastric Cancer
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• 제3권2호
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• pp.80-83
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• 2003

Purpose: Evidence exists that dysregulation of apoptosis is involved in the pathogenesis of cancer development. Fasassociated death domain (FADD) protein, an adaptor protein of death receptors, is a critical regulatory component of the extrinsic cell- death pathway that exerts its pro-apoptotic effect upon binding with death receptors. Expression of the FADD protein has not been reported in stomach cancer. The aim of this study was to explore the expression status of the FADD protein in stomach cancers. Materials and Methods: In the current study, we analyzed the expression of the FADD protein in 60 advanced stomach cancer by using immunohistochemistry and a tissue microarray approach. Results: Immunopositivity (defined as $\geq\30\%$) was observed for the FADD protein in 23 ($38\%$) of the 60 cancers. Normal gastric mucosal cells showed expression of the FADD protein. Conclusion: Taken together, these results indicate that decreased expression of the FADD protein is a frequent event in stomach cancers and suggest that to avoid apoptosis, stomach cancer cells in vivo may need loss of FADD expression, which might contribute to tumor development.

• Journal of Acupuncture Research
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• 제31권2호
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• pp.87-98
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• 2014

Objectives : We investigated whether snake venom toxin(SVT) from Vipera lebetina turanica sensitizes HT29 human epithelial colorectal cancer cells to tumor necrosis factor(TNF)-related apoptosis-inducing ligand(TRAIL) induced apoptosis in cancer cells. Methods : Cell viability assay was used to assess the inhibitory effect of TRAIL on cell growth of HT29 human colorectal cancer cells. And 6-diamidino-2-phenylindole(DAPI), terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay(TUNEL) staining assay were used to evaluate cell-apoptosis. Western blot analysis were conducted to observe apoptosis related proteins and death receptor. To assess whether the synergized inhibitory effect of SVT and TRAIL on reactive oxygen species(ROS) generation was reversed by strong anti-oxidative agent. Results : SVT with TRAIL inhibited HT29 cell growth different from TRAIL alone. Consistent with cell growth inhibition, the expression of TRAIL receptors; Expression of death receptor(DR)4 and DR5 was significantly increased and intrinsic pro-apoptotic cleaved caspase-3, -9 was subsequently increased together with increase of Bax/Bcl-2 ratio and extrinsic pro-apototic caspase-8 was also activated. In addition, the expression of anti-apoptotic survival proteins, a marker of TRAIL resistance(eg, cFLIP, survivin, X-linked inhibitor of apoptosis protein(XIAP) and Bcl-2) was suppressed by the combination treatment of SVT and TRAIL. Pretreatment with the ROS scavenger N-acetylcysteine abolished the SVT and TRAIL-induced upregulation of DR4 and DR5 expression and expression of the intrinsic pro-apoptotic caspase-3 and-9. Conclusion : The collective results suggest that SVT facilitates TRAIL-induced apoptosis in $HT_{29}$ human epithelial colorectal cancer cells through up-regulation of the TRAIL receptors; DR4 and DR5 and consecutive induction of bilateral apoptosis via regulating apoptosis related proteins.

• 동의생리병리학회지
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• 제25권5호
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• pp.816-822
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• 2011

Kaempferol, a component of Polygonati rhizoma, is one of the herbal flavonoids, which is used in therapeutic agent for anti-hypercholesterol, anti-hypertension and anti-diabetes. And it is also known to be effective in anti-cancer therapy for breast, prostate and other type of cancers. However, the anti-cancer therapeutic mechanisms are pooly understood. To address molecular mechanism underlying kaempferol-induced anti-cancer effects, we determined the effect of kaempferol on cell growth of the lung cancer cell lines, A549, H1299 and H460. From the FACS analysis, measurement of caspase activity, DAPI and tryptophan blue staining, and DNA fragmentation assay, we found that kaempferol induces apoptosis and H460 cells are most sensitive among the tested cell lines. In addition, we performed microarray to identify the genome-wide expression profiling regulated by kaempferol. Lots of cell cycle-related genes were under-expressed, whereas the genes related to TGF-beta/SMAD pathway were over-expressed in kaempferol-treated H460 cells. Additionally, kaempferol also increased expression levels of apoptosis related genes such as death receptors, FAS, TRAIL-R and TNF-R, and casepase-8 and caspase-10. Overall, our results suggest that kaempferol promotes anti-lung cancer therapeutic effects by inducing G1 arrest and apoptosis through TGF-beta/SMAD pathway and death receptors/caspase pathway, respectively.

• Reproductive and Developmental Biology
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• 제29권2호
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• pp.101-108
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• 2005

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a well-known inducer of apoptotic cell death in many tumor cells. 1RAIL is expressed in human placenta, and cytotrophoblast cells express 1RAIL receptors. However, the role of TRAIL in human placentas and cytotrophoblast cells is not. well understood. In this study a trophoblast cell line, JEG-3, was used as a model system to examine the effect of TRAIL. on key intracellular signaling pathways involved in the control of trophoblastic cell apoptosis and survival JEG-3 cells expressed receptors for 1RAIL, death receptor (DR) 4, DR5, decoy receptor (OcR) 1 and DeR2. Recombinant human TRAIL (rhTRAIL) did not have a cytotoxic effect determined by MIT assay and did not induce apoptotic cell death determined by poly-(ADP-ribose) polymerase cleavage assay. rhTRAIL induced a rapid and transient nuclear translocation of nuclear $factor-{\kappa}B(NF-{\kappa}B)$ determined by immunoblotting using nuclear protein extracts. rhTRAIL rapidly activated extracellular signal-regulated protein kinase (ERK) 1/2 as determined by immnoblotting for phospho-ERK1/2. However, c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38MAPK) and Akt (protein kinase B) were not activated by rhTRAIL. The ability of 1RAIL to induce $NF-{\kappa}B$ and ERK1/2 suggests that interaction between TRAIL and its receptors may play an important role in trophoblast cell function during pregnancy.

• 생명과학회지
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• 제15권3호
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• pp.505-512
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• 2005

신경흥분독성과 간질발작발현은 glutamate 수용체활성과 연관이 있다고 알려져 있다. a-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA), kainate 수용체에 대한 glutamate 활성을 포함하는 다양한 기전을 가진 항전간제인 Topiramate는 신경보호작용을 가진다는 증거가 제시되어 Topiramate가 간질발작 후 해마의 glutamate 수용체 발현에 미치는 효과를 관찰하였다. 흰쥐에 kainate를 복강 내 주사하여 간질중첩증을 유발시킨 후 Topiramate를 1주일 주사하였다 Apop tag in situ detection kit를 이용하여 세포손상을 관찰한 결과 kainate 유발 간질중첩증 1주일 후 해마의 CA1, CA3에서 심각한 세포사를 보였으나, Topiramte 처리 군에서는 세포사가 현저히 감소하였다. 간질중첩증 이후 NMDA 수용체 아형 1,2a, 2b 발현이 현저히 증가했으나 Topiramate 처치에 의해 NMDA수용체의 발현에는 뚜렷한 변화가 없었다. AMPA수용체에서는 GluR1이 간질중첩증 이후 현저히 상향 조정되었고 GluR2는 현저히 하향조정 되었다 Topiramate 1주일 처리 시 간질중첩증으로 인해 변화된 CluR1과 GluR2의 발현이 역전되었다. 결론적으로 Topiramate는 간질중침증에 의한 CluR1/CluR2 발현비의 증가로 유발되는 흥분성 신경세포사를 억제시킴으로써 신경보호작용이 있는 것으로 보인다.

• BMB Reports
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• 제35권1호
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• pp.67-86
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• 2002

Three routes have been identified triggering neuronal death under physiological and pathological conditions. Excess activation of ionotropic glutamate receptors cause influx and accumulation of $Ca^{2+}$ and $Na^+$ that result in rapid swelling and subsequent neuronal death within a few hours. The second route is caused by oxidative stress due to accumulation of reactive oxygen and nitrogen species. Apoptosis or programmed cell death that often occurs during developmental process has been coined as additional route to pathological neuronal death in the mature nervous system. Evidence is being accumulated that excitotoxicity, oxidative stress, and apoptosis propagate through distinctive and mutually exclusive signal transduction pathway and contribute to neuronal loss following hypoxic-ischemic brain injury. Thus, the therapeutic intervention of hypoxic-ischemic neuronal injury should be aimed to prevent excitotoxicity, oxidative stress, and apoptosis in a concerted way.

• The Korean Journal of Physiology and Pharmacology
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• 제19권1호
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• pp.1-7
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• 2015

Our previous study has shown berberine prevents damage to the intestinal mucosal barrier during early phase of sepsis in rat through mechanisms independent of the NOD-like receptors signaling pathway. In this study, we explored the regulatory effects of berberine on Toll-like receptors during the intestinal mucosal damaging process in rats. Male Sprague-Dawlay (SD) rats were treated with berberine for 5 d before undergoing cecal ligation and puncture (CLP) to induce polymicrobial sepsis. The expression of Toll-like receptor 2 (TLR 2), TLR 4, TLR 9, the activity of nuclear factor-kappa B ($NF-{\kappa}B$), the levels of selected cytokines and chemokines, percentage of cell death in intestinal epithelial cells, and mucosal permeability were investigated at 0, 2, 6, 12 and 24 h after CLP. Results showed that the tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-6 (IL-6) level were significantly lower in berberine-treated rats compared to the control animals. Conversely, the expression level of tight junction proteins, percentage of cell death in intestinal epithelial cells and the mucosal permeability were significantly higher in berberine-treated rats. The mRNA expression of TLR 2, TLR 4, and TLR 9 were significantly affected by berberine treatment. Our results indicate that pretreatment with berberine attenuates tissue injury and protects the intestinal mucosal barrier in early phase of sepsis and this may possibly have been mediated through the TLRs pathway.

• BMB Reports
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• 제47권9호
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• pp.488-493
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• 2014

Adaptor protein FADD forms the death inducing signaling complex (DISC) by recruiting the initiating caspases-8 and -10 through homotypic death effector domain (DED) interactions. Cellular FLICE-inhibitory protein (c-FLIP) is an inhibitor of death ligand-induced apoptosis downstream of death receptors, and FADD competes with procaspase-8/10 for recruitment for DISC. However, the mechanism of action of FADD and c-FLIP proteins remain poorly understood at the molecular level. In this study, we provide evidence indicating that the death effector domain (DED) of FADD interacts directly with the death effector domain of human c-FLIP. In addition, we use homology modeling to develop a molecular docking model of FADD and c-FLIP proteins. We also find that four structure-based mutants (E80A, L84A, K169A and Y171A) of c-FLIP DEDs disturb the interaction with FADD DED, and that these mutations lower the stability of the c-FLIP DED.

• 생명과학회지
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• 제31권10호
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• pp.954-959
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• 2021

세포 사멸은 항상성을 유지하기 위해 세포군을 조절하는 중요한 메커니즘이며 시스테인 단백질분해효소 중 하나인 카스파제는 세포 사멸 경로의 중요한 중재자이다. Caspase-8은 세포외 자극에 의해 시작되는 외인성 세포자멸 경로의 개시자 카스파제이다. Caspase-8에는 보존된 도메인인 N-말단의 두개의 죽음 이펙터 도메인(DED)과 C-말단의 2개의 촉매 도메인을 가지며, 이는 이러한 외인성 세포자멸 경로에 중요하게 작용한다. 외인성 세포멸사 경로에서, TNF 슈퍼패밀리인 죽음 수용체는 세포 외부로부터의 죽음 수용체 특이적 리간드의 결합에 의해 활성화된다. 활성화된 죽음 수용체가 어댑터 단백질인 Fas-associated death domain 단백질(FADD)을 모집한 후, 죽음 수용체와 FADD의 죽음 도메인(DD)이 서로 결합하고 죽음 수용체와 결합한 FADD가 caspase-8의 전구체 형태인 procaspase-8을 모집한다. FADD와 procaspase-8의 죽음 이펙터 도메인은 서로 결합하고 FADD에 결합된 procaspase-8은 prodomain의 절단에 의해 활성화된다. 이 죽음 수용체-FADD-caspase-8 복합체는 세포사멸 유도 신호복합체(DISC)라고 한다. 세포 FLICE 억제 단백질(c-FLIPs)은 세포사멸을 억제하는 역할과 촉진하는 역할을 모두 수행하여 caspase-8의 활성화를 조절하고 caspase-8 활성화는 caspase-3와 같은 작동자 카스파제를 활성화를 시킨다. 마지막으로 활성화된 작동자 카스파제는 DNA 분해, 핵 응축, 세포막 수포 및 카스파제 기질의 단백질 분해에 작용하여 세포사멸을 완료한다.

• Journal of Acupuncture Research
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• 제31권1호
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• pp.121-130
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• 2014

Objectives : I investigated whether bee venom inhibit cell growth through enhancement of death receptor expressions in the human lung cancer cells, NCI-H460. Methods : Bee venom(1-5 ${\mu}g/ml$) inhibited the growth of NCI-H460 lung cancer cells by the induction of apoptotic cell death in a dose dependent manner. Results : Consistent with apoptotic cell death, expression of TNF-R1, TNF-R2, FAS, death receptors(DR) 3, 4, 5 and 6 was increased in the cells. Expression of DR downstream pro-apoptotic proteins including Caspase-8, -3, -9 was upregulated and Bax was concomitantly overwhelmed the expression of Bcl-2. NF-kB were inhibited by treatment with bee venom in NCI-H460 cells through TNF response change led by TNF-R1 and TNF-R2. Conclusions : These results suggest that bee venom should exert anti-tumor effect through induction of apoptotic cell death in NCI-H460 human lung cancer cells via enhancement of death receptor expression, and that bee venom could be a promising agent for preventing and treating lung cancer.