• Biomolecules & Therapeutics
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• 제19권2호
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• pp.195-200
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• 2011

Neuronal cell death is a common characteristic feature of a variety of neurodegenerative disorders including Alzheimer's disease and Parkinson's disease. However, there have been no effective drugs to successfully prevent neuronal death in those diseases. In the present study, docosyl cafferate (DC), a derivative of caffeic acid, was isolated from Rhus verniciflua and its protective effects on tBHP-induced neuronal cell death were examined in SH-SY5Y human neuroblastoma cells. Pretreatment of DC significantly attenuated tBHP-induced neuronal cell death in a concentration-dependent manner. DC also significantly suppressed tBHP-induced caspase-3 activation. In addition, DC restored tBHP-induced depletion of intracellular Bcl-2, an anti-apoptotic member of the Bcl-2 family. Furthermore, DC significantly suppressed tBHP-induced degradation of IKB, which retains $NF-{\kappa}B$ in the cytoplasm, resulting in the suppression of nuclear translocation of $NF-{\kappa}B$ and its subsequent activation. Taken together, the results clearly demonstrate that DC exerts its neuroprotective activity against tBHP-induced oxidative stress through the suppression of nuclear translocation of $NF-{\kappa}B$.

• Journal of Chest Surgery
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• 제39권9호
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• pp.668-673
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• 2006

Taxene 계 화학요법제로서 항암치료에 사용되고 있는 docetaxel 은 폐암을 포함한 다양한 종양에서 효과적인 항암 치료제로 사용되고 있다. Docetaxel 에 의한 폐암세포의 사멸 유도 기전은 정확히 알려져 있지 않으며, 기전을 연구하기 위해 docetaxel로 처리한 NCI-H1703 세포의 세포주기 및 형태적 변화를 유세포측정기, 형광현미경, western blot 분석법을 통하여 확인하였다. 그 결과 docetaxel 은 의미 있게 S기를 감소시키고 G2기를 증가시킴으로써 NCI-H1703 세포의 사멸을 증가시켰다. Docetaxel에 노출되었을 때 caspase-3와 caspase-9의 활성이 증가되었다. 이들 결과를 종합해볼때, docetaxel 은 H1703 의 세포사멸 유도 시 caspase-3 의존성 미토콘드리아 관련 세포사멸기전으로 apoptosis를 일으키는 것으로 생각한다.

• BMB Reports
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• 제36권4호
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• pp.337-343
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• 2003

Rhus verniciflua Stokes (RVS) has been used as a traditional herbal medicine. Several earlier studies indicated that an ethanol extract of RVS has both anti-oxidant and anti-tumor properties, although the mechanism for the activity remains to be elucidated. In this report, we prepared a highly purified ethanol extract from RVS, named REEE-1 ($\underline{R}$hus $\underline{e}$thanol $\underline{e}$luted $\underline{e}$xtract-1), and investigated the mechanism involved in its growth-inhibitory effect on the human B and T lymphoma cell lines, BJAB and Jurkat, respectively. Results from tritium uptake proliferation assays showed that the proliferative capacities of both BJAB and Jurkat cells were strongly suppressed in the presence of REEE-1. This was further confirmed through trypan blue exclusion experiments that revealed a dose-dependent decrease in viable cell numbers after REEE-1 treatment. REEE-1-mediated suppression of cell growth was verified to be apoptotic, based on the increase in DNA fragmentation, low fluorescence intensity in nuclei after propidium iodide staining, and the appearance of DNA laddering. In particular, REEE-1 exerted its anti-oxidant activity through the inhibition of hydroxyl radical-mediated degradation by iron ion chelation rather than direct scavenging of hydroxyl radicals. Furthermore, REEE-1 was revealed to be a potential scavenger of superoxide anions. Collectively, our findings suggest that REEE-1 is a natural anti-oxidant that could be used as a cancer chemo-preventive and therapeutic agent.

• 대한바이러스학회지
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• 제30권2호
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• pp.141-150
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• 2000

The effectiveness of noninfectious recombinant adenovirus encoding murine granulocyte-macrophage colony stimulating factor (mGM-CSF) for the treatment of Meth A fibrosarcoma was investigated in syngeneic BALB/C model. Meth A and HeLa cells transduced with the recombinant adenovirus (Ad.mGM-CSF) produced substantial amounts of mGM-CSF, while WEH1164 cells transduced with the virus did not produce mGM-CSF. Mice inoculated subcutaneously with $1{\times}10^6$ Meth A cells, followed by injection of Ad.dE1 as a control, developed large tumors that reached a mean tumor size of 22 mm by day 30. However, tumor development and tumorigenicity were significantly inhibited in mice with a single intratumoral injection of Ad.mGM-CSF at $1{\times}10^8\;pfu$. Histological examination of the tumors injected with Ad.mGM-CSF revealed dense infiltrates of neutrophils, histiocytes, lymphocytes, and eosinophils associated with apoptotic cell death. The results suggest that the recombinant adenovirus encoding GM-CSF have a potential use for cancer gene therapy.

• Molecules and Cells
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• 제38권5호
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• pp.416-425
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• 2015

NF-E2-related factor 2 (Nrf2), a basic leucine zipper transcription factor, has recently received a great deal of attention as an important molecule that enhances antioxidative defenses and induces resistance to chemotherapy or radiotherapy. In this study, we investigated the apoptosis-inducing and Nrf2- upregulating effects of quercetin on malignant mesothelioma (MM) MSTO-211H and H2452 cells. Quercetin treatment inhibited cell growth and led to upregulation of Nrf2 at both the mRNA and protein levels without altering the ubiquitination and extending the half-life of the Nrf2 protein. Following treatment with quercetin, analyses of the nuclear level of Nrf2, Nrf2 antioxidant response element-binding assay, Nrf2 promoter-luc assay, and RT-PCR toward the Nrf2-regulated gene, heme oxygenase-1, demonstrated that the induced Nrf2 is transcriptionally active. Knockdown of Nrf2 expression with siRNA enhanced cytotoxicity due to the induction of apoptosis, as evidenced by an increase in the level of proapoptotic Bax, a decrease in the level of antiapoptotic Bcl-2 with enhanced cleavage of caspase-3 and PARP proteins, the appearance of a sub-$G_0/G_1$ peak in the flow cytometric assay, and increased percentage of apoptotic propensities in the annexin V binding assay. Effective reversal of apoptosis was observed following pretreatment with the pan-caspase inhibitor Z-VAD. Moreover, Nrf2 knockdown exhibited increased sensitivity to the anticancer drug, cisplatin, presumably by potentiating the oxidative stress induced by cisplatin. Collectively, our data demonstrate the importance of Nrf2 in cytoprotection, survival, and drug resistance with implications for the potential significance of targeting Nrf2 as a promising strategy for overcoming resistance to chemotherapeutics in MM.

• 대한수의학회지
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• 제53권1호
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• pp.11-17
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• 2013

In this study, to understand the pathogenesis of new rabbit hemorrhagic disease virus (RHDVa) serotype, we carried out to administrate RHDVa to rabbits, and to examine sequential electron microscopic changes and relationship between pathogenesis and apoptosis. TUNEL-positive cells began to be observed from 24 hours after inoculation (HAI) and the number of positive cells was slightly increased with the course of time. Whereas marked increase of positive cells was seen in the liver from the rabbits died acutely. Typical viral particles with cup-like projections and a diameter of 30~40 nm were detected in homogenized liver samples and tissues at 36 and 48, and 48 HAI, respectively. Ultrastructurally, glycogen deposition was observed from the first stage of hepatocellular degeneration by RHDVa infection and then, swelling and disruption of cristae of mitochondria by viral particles, swelling of smooth endoplasmic reticulum, vacuoles and vesicles were detected. Condensation, margination and fragmentation of chromatin were observed in degenerative hepatocytes at 36 and 48 HAI, indicating apoptotic bodies. These data offer that hepatocytic apoptosis by RHDV infection could be closely related with mitochondrial impairment in the hepatocytes.

• Applied Biological Chemistry
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• 제44권1호
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• pp.1-6
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• 2001

본 연구에서는 Ttichoplusia ni 세포의 apoptosis 유도 및 억제 현상의 기초연구를 수행하였다. Apoptosis 유도제로 알려진 hygromycin B에 의한 세포 성장 저해는 $200\;{\mu}/ml$의 수준에서부터 나타났고, $400\;{\mu}/ml$ hygromycin B를 처리한 세포에서는 배양 후 2일부터 DNA가 분절되어지는 것을 확인할 수 있었다. 그러나 dexamethasone과 sodium butyrate를 첨가시 세포성장은 저해되었지만 DNA 분절현상이 보이지 않아 apoptosi의 유발여부를 확인할 수 없었다. 그리고 caspase 기능억제제의 apoptosis 지연효과를 보기 위해 $200\;{\mu}/ml$ hygromycin B로 apoptosis를 유발한 상태에서 Ac-DEVD-CHO를 첨가하여 세포성장을 비교해 본 결과 이 저해제에 의해 약 36%정도 apoptosis가 억제되었음을 확인하였다. N-acetylcysteine의 경우도 apoptosis지연 효과가 있었다. Bcl_계에 속하는 anti-apoptotic 유전자의 발현연구로서 apoptosis 저해 단백질인 bcl-2 유전자를 곤충세포에 형질전환시킨 후 이 단백질이 한시적으로 발현되는 것을 western blot분석법으로 확인하였으며 apoptosis가 지연된 곤충세포주의 개발이 가능하다는 결론을 보였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권1호
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• pp.7-12
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• 2006

Telomerase activation is detected in most cancerous cells; hence, telomerase is a highly selective target for cancer therapy, which plays an important role in the apoptotic process. We have previously reported that the ginseng saponin metabolite, Compound K (20-O-D-glucopyranosyl-20(S)-protopanaxadiol, IH901), inhibits cell proliferation by inducing apoptosis and cell cycle arrest at the $G_1$ phase. The present study investigated the regulation of telomerase activity in Compound K treated U937 cells. Compound K treatment caused a reduction in telomerase activity and down-regulated the human telomerase reverse transcriptase (hTERT) gene, resulting in the decreased expressions of its protein, and of the c-Myc and Spl proteins (transcription factors of hTERT). These results indicate that the anticancer activity of Compound K could be mediated by inhibition of the telomerase activity.

• 대한본초학회지
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• 제26권3호
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• pp.65-73
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• 2011

Objectives : The present study was evaluated the protective roles of Spatholobi Caulis in hepatotoxic rats due to APAP overdose. Methods : In experiments, rats were orally administrated with the aqueous extract of Spatholobi Caulis (SCE; 50, 100 mg/kg) for 4 days and then, orally gavage with APAP (1.2 g/kg) to induce acute liver damage. Results : Oral injection of APAP caused severe hepatic injury. Plasma ALT, AST and LDH levels were significantly elevated, but SCE significantly decreased ALT, AST and LDH to the normal level. In histopathological analysis, peripheral hemorrhage around portal triads and central necrosis around central veins were founded after APAP treatment. However, these histopathological changes were recovered by SCE pretreatment. SCE also decreased the percentage of generative hepatic regions (%/$mm^2$ hepatic parenchyma), the numbers of inflammatory cells (cells/$mm^2$ hepatic parenchyma) and the number of degenerative hepatic cells (N/100 hepatic cellls) which were significantly elevated after APAP injection. Furthermore, SCE down-regulated the contents of hepatic MDA and up-regulated hepatic GSH. SCE also inhibited the decrease in the expression of pro-caspase-3 by APAP treatment. Conclusions : Collectively, these data indicate that SCE protected APAP-induced hapatic damages through antioxidative and anti-apoptotic process. These findings the significant therapeutic potential of SCE during APAP-induced liver injury.

• Animal cells and systems
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• 제12권2호
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• pp.69-75
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• 2008

The tumor suppressor and transcription factor p53 is a key modulator of cellular stress responses, and can trigger apoptosis in many cell types including neurons. In this study, we have shown that Microtubule-associated protein 1B(MAP1B) light chain interacts with tumor suppressor p53. MAP1B is one of the major cytoskeletal proteins in the developing nervous system and essential in forming axons during elongation. We also demonstrate that both p53 and MAP1B-LC1 interact in the nucleus in HEK 293 cells. Indeed, we show that the MAP1B-LC1 negatively regulates p53-dependent transcriptional activity of a reporter containing the p21 promoter. Consequently, MAP1B light chain binds with p53 and their interaction leads to the inhibition of doxorubicin-induced apoptosis in HEK 293 cells. Furthermore, these examinations might be taken into consideration when knock-down of MAP1B-LC1 is used as a cancer therapeutic strategy to enhance p53's apoptotic activity in chemotherapy.