• 생명과학회지
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• 제15권3호
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• pp.323-331
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• 2005

남미지역에서 자생하는 Tabebuia avellanedae라는 나무의 수피에서 동정된 quinone계 물질이며, DNA topoisomeras억제제로 알려진 $\beta-lapachone$의 항암작용에 관한 부가적인 자료를 얻기 위하여 인체 간암(HepG2) 및 방광암(T24)세포를 대상으로 조사한 결과 다음과 같은 결과를 얻게 되었다. MTT assay 및 flow cytometry 분석 등의 결과에서, $\beta-lapachone$의 처리에 따라 조사된 두 가지 암세포에서 $\beta-lapachone$처리 농도의존적으로 암세포의 심한 형태적 변형이 동반되면서 암세포의 증식이 억제되었으며, 생존율이 저하되었고 이는 apoptosis유발과 상관성이 있음을 알 수 있었다. $\beta-lapachone$처리에 의한 두 암세포의 증식억제는 종양억제 유전자 p53 및 Cdk inhibitor p21의 발현과는 큰 연관성이 없음을 RT-PCR 및 Western blot analysis를 통하여 확인하였다. 그러나 전사조절인자 Sp-1 및 세포증식 주요조절인자인 PCNA의 단백질 발현은 $\beta-lapachone$처리에 따라 매우 감소되었으며, telomere조절에 중요한 인자들의 선택적 발현 저하 현상도 관찰되었다. 이상의 결과들은 인체 암세포에서 $\beta-lapachone$의 항암작용을 이해하는 중요한 자료가 될 것이며, $\beta-lapachone$과 유사한 화학적 구조 및 성질을 가지는 항암제 후보물질들의 항암기전 비교 및 항암제 개발을 위한 기초 자료로서 응용될 것이다.

• 생명과학회지
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• 제24권7호
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• pp.769-776
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• 2014

Anisomycin은 Streptomyces griseolus에 의하여 생성되는 항생제의 일종으로 flagecidin으로도 알려져 있으며, ribosomal 28S subunit에 결합함으로서 단백질의 생성을 억제하는 것으로 알려져 있다. TRAIL은 ligand로서의 death receptor와의 결합을 통하여 세포의 apoptosis를 유발하는 것으로 알려져 있으나, 많은 암세포에서는 이미 TRAIL에 대한 저항성을 획득하여 TRAIL 유도 apoptosis를 회피하는 능력을 가지고 있다. 본 연구에서는 TRAIL 저항성 Hep3B 간암세포를 대상으로 anisomycin이 TRAIL 매개 apoptosis를 촉진 시킬 수 있는지의 여부를 조사하였다. 본 연구의 결과에 의하면, 단독 처리 조건에서 Hep3B 세포의 증식에 유의적인 영향을 미치는 않았던 anisomycin과 TRAIL의 동시 처리는 anisomycin 처리 농도 의존적으로 세포의 증식을 시켰으며, 이는 caspase 활성화를 통한 apoptosis 유발 증가와 연관성이 있음을 확인하였다. 특히 siRNA를 이용한 Hep3B 세포의 인위적인 Bid 발현의 차단은 anisomycin과 TRAIL 동시 처리군에 비하여 apoptosis 유발능이 더욱 증대시켜 TRAIL 연관 Bid의 truncation을 통한 미토콘드리아 의존적 apoptosis 유발 과정을 anisomycin이 효과적으로 촉진시켰음을 보여주었다. 따라서 본 연구의 결과는 anisomycin과 TRAIL의 동시 처리는 TRAIL 저항성 암세포의 사멸을 촉진시킬 수 있는 효과적인 방법임을 의미한다.

• IMMUNE NETWORK
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• 제2권1호
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• pp.53-59
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• 2002

Background: Clinical observations and laboratory studies have supported an immune basis for most acquired aplastic anemias, with the majority of patients responding to immunosuppressive therapy. Fas, a member of the tumor necrosis factor (TNF) receptor superfamily is a critical downregulator of cellular immune responses. Proinflammatory cytokines like interferon gamma (IFN-${\gamma}$) and TNF-${\alpha}$ can induce Fas expression and render hematopoietic progenitor cells susceptible to Fas-induced growth suppression and apoptosis. Methods: In order to investigate the involvement of apoptosis in the pathogenesis of aplastic anemia (AA), we measured the expression of Fas antigen and caspase-3 on bone marrow (BM) mononuclear cells (MNCs) of AA in the presence or absence of IFN-${\gamma}$, TNF-${\alpha}$, or macrophage inflammatory protein 1-${\alpha}$ (MIP-$1{\alpha}$). Results: We confirmed that AA BM MNCs were more apoptotic and highly expressed Fas antigen than normal donors. Stimulation by IFN-${\gamma}$, TNF-${\alpha}$, or MIP-$1{\alpha}$ increased Fas antigen and caspase-3 expression in AA BM MNCs than BM MNCs of normal donors. Anti-Fas monoclonal antibody enhanced IFN-${\gamma}$, TNF-${\alpha}$, or MIP$1{\alpha}$ mediated caspase-3 expression in BM MNCs of normal donors. Among these three cytokines, IFN-${\gamma}$ enhanced apoptosis most strongly via Fas-caspase-3 pathway. Conclusion: These results suggest that Fas signal pathway may play a role in the pathophysiology of aplastic anemia and negative hematopoietic regulators like IFN-${\gamma}$ can induce apoptosis of bone marrow progenitors in part by Fas induction.

• Journal of Acupuncture Research
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• 제31권1호
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• pp.111-119
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• 2014

Objectives : I investigated whether Bee Venom can synergistically strengthen the cytotoxic effects of NK-92 cells, enhancing the inhibition of the growth of Lung Cancer Cells including A549 and NCI-H460 through induction of death receptor dependent extrinsic apoptosis and NO generation in the Nitro-oxide pathway. Methods : Bee Venom inhibited cell proliferation of A549 or NCI-H460 Human Lung Cancer Cells as well as NK-92 Cells. Moreover, when they were co-punctured with NK cells and concomitantly treated by 3 ${\mu}g/ml$ of Bee Venom, more influence was exerted on inhibition of proliferation of A549 or NCI-H460 Human Lung Cancer Cells than BV or NK cell co-culture alone. Results : The expression of Fas, TNFR2, DR3, DR6 in A549 Lung Cancer Cells was significantly increased by co-culture of NK-92 cells and treatment of 3 ${\mu}g/ml$ of Bee Venom, compared to co-culture of NK-92 cells alone, whereas the expression of Fas, TNFR2, DR6 in NCI-H460 Lung Cancer Cells was significantly increased by co-culture of NK-92 cells, representing no synergistic effects in the co-culture of NK-92 cell and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom. Coincidently, caspase-8, a expression of pro-apoptotic proteins in the extrinsic apoptosis pathway demonstrated same results as the above. Meanwhile, In NO generation, there is little change of NO generation in co-culture of NK-92 cells with A549 cells as well as the co-culture of NK-92 cell with them and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom, whereas increase of NO generation was shown in co-culture of NK-92 cells with NCI-H460 cells as well as the co-culture of NK-92 cell with them and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom, although synergistic effects by Bee Venom was not found. Conclusions : These present data provide that Bee Venom could be useful candidate compounds to enhance lung cancer growth inhibiting ability of NK-92 cells through DR expression and the related apoptosis.

• 한국식품영양과학회지
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• 제43권12호
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• pp.1827-1834
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• 2014

천년초 에탄올 추출물이 인체 대장암 세포 HT-29의 세포사멸에 미치는 영향과 기능성 식품 소재로서의 가능성을 시사하고자 본 연구를 수행하였다. 연구 내용은 천년초의 일반성분 분석과 천년초 에탄올 추출물의 처리 농도에 따른 인체대장암 세포의 증식과 세포사멸 현상을 비교 관찰하고 항암효과의 가능성을 확인하고자 하였다. 천년초 분말의 일반성분 분석을 진행한 결과 탄수화물의 함량과 마그네슘 등의 양이온의 함량이 높았고 Na/K의 비율과 P:Ca의 비율이 매우 낮았다. 천년초 70% 에탄올, 메탄올, 열수 추출물을 0.25, 0.5, 1, 2 mg/mL의 농도로 HT-29 세포에 48시간 처리하고 WST를 이용한 세포 생존율을 측정한 결과는 모든 군에서 세포증식이 억제되었으며(P<0.05), 특히 에탄올 추출물이 농도 의존적으로 유의한 효능을 보였다. Hoechst 33342 & PI로 이중으로 핵을 염색해서 세포사를 관찰한 결과 시료농도가 증가할수록 apoptotic body가 증가하였으며, 특히 1 mg/mL의 농도 이상에서 급격히 증가하여 2 mg/mL에서는 세포사를 관찰할 수 있었다. Annexin V & PI double staining을 통하여 저농도(0.25~0.5 mg/mL) 시료 처치군에서는 전반적으로 apoptosis의 비율이 증가하였고 고농도(1~2 mg/mL)로 처리한 군에서는 dead cell이 84.7%, 89.3% 나타나 세포가 세포 사멸과정을 거쳐 세포괴사로 진행된 것으로 추측되었다. 또한 comet assay를 통해 용매 대조군에 비해 1~2 mg/mL 농도에서 유의하게 DNA가 분절되었음을 확인하였다(P<0.05). 따라서 천년초 에탄올 추출물은 인체 유래 대장암 세포 HT-29의 세포증식을 억제하고 항산화 효과가 있는 것으로 나타나 천년초의 항암 가능성을 보여 주었으나, 확실한 효과와 기전을 파악하기 위하여 심도 있는 연구가 필요로 된다.

• International Journal of Oral Biology
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• 제40권2호
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• pp.63-69
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• 2015

Curcumin (diferuloylmethane), a constituent of turmeric powder derived from the rhizome of Curcuma longa, has been shown to inhibit the growth of various types of cancer cells by regulating cell proliferation and apoptosis. However, a need exists to design more effective analogs because of curcumin's poor intestinal absorption. EF-24 (diphenyl difluoroketone), the monoketone analog of curcumin, has shown good efficacy in anticancer screens. However, the effects of curcumin and EF-24 on salivary gland epidermoid carcinoma cells are not clearly established. The main goal of this study was to investigate the effects of curcumin and EF-24 on cell growth and induction of apoptosis in human salivary gland epidermoid carcinoma cells. Our studies showed that curcumin and EF-24 inhibited the growth of HTB-41 cells in a dose- and time-dependent manner, and the potency of EF-24 was > 34-fold that of curcumin. Treatment with curcumin or EF-24 resulted in nuclear condensation and fragmentation in HTB-41 cells, whereas the control HTB-41 cell nuclei retained their normal regular and oval shape. Curcumin and EF-24 promoted proteolytic cleavages of procaspase-3/-7/-9, resulting in an increase in the amount of cleaved caspase-3/-7/-9 in the HTB-41 cells. Caspase-3 and -7 activities were detected in viable HTB-41 cells treated with curcumin or EF-24. These results suggest that the curcumin and EF-24 inhibit cell proliferation and induce apoptosis in HTB-41 human salivary gland epidermoid carcinoma cells, and that they may have potential properties as an anti-cancer drug therapy.

• 생명과학회지
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• 제20권7호
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• pp.1121-1126
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• 2010

활성산소에 의해 유도되는 산화적 스트레스가 노화와 관련된 각종 퇴행성 신경질환의 원인으로 밝혀짐에 따라 본 연구에서는 활성산소종인 $H_2O_2$가 유도하는 강력한 산화적 스트레스로부터 신경세포를 보호하는 물질을 탐색하기 위하여 하고초 추출물(PSE)에 관하여 연구하였다. PC12 세포를 이용하여 MTT reduction assay, LDH release assay 및 colony formation assay 등 여러 가지 생물학적인 assay를 통하여 PSE의 세포 보호효과를 확인하였다. 그리고 광학 현미경을 이용한 형태학적 변화 관찰에서도 $H_2O_2$ 처리군에 비해 높은 세포 보호효과를 확인할 수 있었으며, Hoechst 33342 염색과 세포주기 분석을 통하여 PSE의 높은 apoptosis 억제효과를 확인할 수 있었다. 이상의 결과로부터 하고초는 $H_2O_2$에 의해 유도된 세포독성으로부터 PC12 세포손상을 강력하게 억제하는 효과가 있다는 것을 확인할 수 있었으며, 퇴행성 신경질환에 대한 새로운 치료제로서의 가능성을 제시하였다.

• Molecules and Cells
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• 제37권11호
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• pp.785-794
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• 2014

Mitophagy, a cellular process that selectively targets dysfunctional mitochondria for degradation, is currently a hot topic in research into the pathogenesis and treatment of many human diseases. Considering that hypoxia causes mitochondrial dysfunction, which results in cell death, we speculated that selective activation of mitophagy might promote cell survival under hypoxic conditions. In the present study, we introduced the Regulator of calcineurin 1-1L (Rcan1-1L) to initiate the mitophagy pathway and aimed to evaluate the effect of Rcan1-1L-induced mitophagy on cell survival under hypoxic conditions. Recombinant adenovirus vectors carrying Rcan1-1L were transfected into human umbilical vein endothelial cells and human adult cardiac myocytes. Using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay and Trypan blue exclusion assay, Rcan1-1L overexpression was found to markedly reverse cell growth inhibition induced by hypoxia. Additionally, Rcan1-1L overexpression inhibited cell apoptosis under hypoxic conditions, as detected by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) apoptosis assay. Meanwhile, the mitochondria-mediated cell apoptotic pathway was inhibited by Rcan1-1L. In contrast, knockdown of Rcan1-1L accelerated hypoxia-induced cell apoptosis. Moreover, Rcan1-1L overexpression significantly reduced mitochondrial mass, decreased depolarized mitochondria, and downregulated ATP and reactive oxygen species production. We further delineated that the loss of mitochondrial mass was due to the activation of mitophagy induced by Rcan1-1L. Rcan1-1L overexpression activated autophagy flux and promoted translocation of the specific mitophagy receptor Parkin into mitochondria from the cytosol, whereas inhibition of autophagy flux resulted in the accumulation of Parkin-loaded mitochondria. Finally, we demonstrated that mitochondrial 1permeability transition pore opening was significantly increased by Rcan1-1L overexpression, which suggested that Rcan1-1L might evoke mitophagy through regulating mitochondrial permeability transition pores. Taken together, we provide evidence that Rcan1-1L overexpression induces mitophagy, which in turn contributes to cell survival under hypoxic conditions, revealing for the first time that Rcan1-1L-induced mitophagy may be used for cardioprotection.

• The Korean Journal of Physiology and Pharmacology
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• 제4권1호
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• pp.47-54
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• 2000

Transition metal ions including $Se^{2+},\;Cd^{2+},\;Hg^{2+}\;or\;Mn^{2+}$ have been thought to disturb the bone metabolism directly. However, the mechanism for the bone lesion is unknown. In this study, we demonstrated that MC3T3E1 osteoblasts, exposed to various transition metal ions; selenium, cadmium, mercury or manganese, generated massive amounts of reactive oxygen species (ROS). The released ROS were completely quenched by free radical scavengers-N-acetyl cysteine (NAC), reduced glutathione (GSH), or superoxide dismutase (SOD). First, we have observed that selenium $(10\;{\mu}M),$ cadmium $(100\;{\mu}M),$ mercury $(100\;{\mu}M)$ or manganese (1 mM) treatment induced apoptotic phenomena like DNA fragmentation, chromatin condensation and caspase-3-like cysteine protease activation in MC3T3E1 osteoblasts. Concomitant treatment of antioxidant; N-acetyl-L-cysteine (NAC), reduced-form glutathione (GSH), or superoxide dismutase (SOD), prevented apoptosis induced by each of the transition metal ions. Catalase or dimethylsulfoxide (DMSO) has less potent inhibitory effect on the apoptosis, compared with NAC, GSH or SOD. In line with the results, nitroblue tetrazolium (NBT) stain shows that each of the transition metals is a potent source of free radicals in MC3T3E1 osteoblast. Our data show that oxidative damage is associated with the induction of apoptosis in MC3T3E1 osteoblasts following $Se^{2+},\;Cd^{2+},\;Hg^{2+}\;or\;Mn^{2+}$ treatment.

• Biomolecules & Therapeutics
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• 제28권5호
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• pp.443-455
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• 2020

The thioredoxin (Trx) system plays critical roles in regulating intracellular redox levels and defending organisms against oxidative stress. Recent studies indicated that Trx reductase (TrxR) was overexpressed in various types of human cancer cells indicating that the Trx-TrxR system may be a potential target for anti-cancer drug development. This study investigated the synergistic effect of auranofin, a TrxR-specific inhibitor, on sulforaphane-mediated apoptotic cell death using Hep3B cells. The results showed that sulforaphane significantly enhanced auranofin-induced apoptosis by inhibiting TrxR activity and cell proliferation compared to either single treatment. The synergistic effect of sulforaphane and auranofin on apoptosis was evidenced by an increased annexin-V-positive cells and Sub-G1 cells. The induction of apoptosis by the combined treatment caused the loss of mitochondrial membrane potential (ΔΨm) and upregulation of Bax. In addition, the proteolytic activities of caspases (-3, -8, and -9) and the degradation of poly (ADP-ribose) polymerase, a substrate protein of activated caspase-3, were also higher in the combined treatment. Moreover, combined treatment induced excessive generation of reactive oxygen species (ROS). However, treatment with N-acetyl-L-cysteine, a ROS scavenger, reduced combined treatment-induced ROS production and apoptosis. Thereby, these results deduce that ROS played a pivotal role in apoptosis induced by auranofin and sulforaphane. Furthermore, apoptosis induced by auranofin and sulforaphane was significantly increased through inhibition of the phosphoinositide 3-kinase (PI3K)/Akt pathway. Taken together, the present study demonstrated that down-regulation of TrxR activity contributed to the synergistic effect of auranofin and sulforaphane on apoptosis through ROS production and inhibition of PI3K/Akt signaling pathway.