• Biomolecules & Therapeutics
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• 제15권3호
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• pp.137-144
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• 2007

Although lovastatin, a competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMGCoA) reductase, has been shown to have anti-cancer actions, the effect on human hepatoma cells was not investigated. Moreover, the exact mechanism of this action is not fully understood. In this study we investigated the mechanism by which lovastatin induces apoptosis using HepG2 human hepatoblastoma cells. Lovastatin induced apoptotic cell death in a dose-dependent manner in the cells, assessed by the flow cytometric analysis. Treatment with mevalonic acid, a precursor of cholesterol, did not significantly suppress the lovastatin-induced apoptosis. Lovastatin induced a rapid and sustained increase in intracellular $Ca^{2+}$ concentration. Treatment with EGTA, an extracellular $Ca^{2+}$ chelator did not significantly alter the lovastatin-induced intracellular $Ca^{2+}$ increase and apoptosis, whereas intracellular $Ca^{2+}$ reduction with BAPTA/AM and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8) completely blocked these actions of lovastatin. In addition, the lovastatin-induced apoptosis was significantly reduced by a calpain inhibitor, a broad spectrum caspase inhibitor z-VAD-fmk and inhibitors specific for caspase-9 and caspase-3 (z-LEHD-fmk and z-DEVD-fmk, respectively), but not by an inhibitor specific for caspase-8 (z-IETD-fmk). Collectively, these results suggest that lovastatin induced apoptosis of HepG2 hepatoma cells through intracellular $Ca^{2+}$ release and calpain activation, leading to triggering mitochondrial apoptotic pathway. These results further suggest that lovastatin may be valuable for the therapeutic management of human hepatoma.

• 약학회지
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• 제59권1호
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• pp.17-22
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• 2015

In this study, we examined the effect of acacetin on the apoptosis induction of HeLa human cervical cancer cells. The results showed that acacetin inhibited the cell viability and induced apoptosis, leading to PARP cleavage and activation of caspase-9, -3, and -7. Moreover, acacetin-induced apoptosis was attenuated by a broad caspase inhibitor, z-VAD-fmk. Also, acacetin resulted in a loss of mitochondria membrane potential. Taken together, our results demonstrate that the induction of apoptosis by acacetin in HeLa cells is associated with caspase activation via the mitochondria pathway.

• 대한의생명과학회지
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• 제26권3호
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• pp.179-185
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• 2020

Adenine, a purine base, is a structural component of essential biomolecules such as nucleic acids and adenine nucleotides. Its physiological roles have been uncovered. Adenine suppresses IgE-mediated allergy and LPS-induced inflammation. Although adenine is known to inhibit lymphocyte proliferation, the effect of adenine to melamoma cells is not reported. Here, we investigated the growth inhibitory effects of adenine on B16-F10 mouse melanoma cells. Adenine suppressed the proliferation of B16-F10 cells in dose-dependent manner with the maximal inhibitory dose of 2 mM. Adenine treatment induced cell death molecular markers such as PARP and caspase 3 cleavages. Pan-caspase inhibitor z-VAD dramatically rescued the cell death molecular markers, cell proliferation recovered marginally. These results provide the possibility of adenine to be used as an anti-tumor agent.

• Archives of Pharmacal Research
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• 제26권11호
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• pp.937-942
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• 2003

Nitric oxide(NO) induces apoptosis in human osteoblasts. Treatment with exogenous NO donors, SNAP (S-Nitroso-N-acelylpenicillamine) and SNP (sodium nitroprusside), to MG-63 osteoblasts resulted in apoptotic morphological changes, as shown by a bright blue-fluorescent condensed nuclei and chromatin fragmentation by fluorescence microscope of Hoechst 33258-staining. The activities of caspase-9 and the subsequent caspase-3-like cysteine proteases were increased during NO-induced cell death. Pretreatment with Z-VAD-FMK (a pancaspase inhibitor) or Ac-DEVD-CHO (a specific caspase-3 inhibitor) abrogated the NO-induced cell death. The NO donor markedly activated JNK, a stress-activated protein kinase in the human osteoblasts. This study showed that the inhibition of the JNK pathway markedly reduced NO-induced cell death. But neither PD98059 (MEK inhibitor) nor SB203580 (p38 MAPK inhibitor) had any effect on NO-induced death. Taken together, these results suggest that JNK/SAPK may be related to NO-induced apoptosis in MG-63 human osteoblasts.

• 약학회지
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• 제43권3호
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• pp.385-390
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• 1999

Camptothecin (CPT) has been known to induce apoptosis in various cancer cell lines. To examine the intracellular apoptotic death signal initiated by CPT, we investigated the possible connection between caspase-3 activation and GSH depletion during CPT-induced apoptosis in HL-60 cells. Treatment of cells with $1{\;}{\mu}M$ CPT induced PARP cleavage accompanied by DNA fragmentation. z-VAD-fmk, a caspase-3 inhibitor, blocked the CPT-induced DNA fragmentation. Pretreatment of cells with N-acetylcysteine, a precursor of GSH biosynthesis, failed to inhibit CPT-induced PARP celavage and DNA gragmenatation. No significant changes in GSH depletion is not essential for caspase activation during CPT-induced apoptosis. We also investigated whether CPT-induced apoptosis is associated with changes of the levels of Bax and Bcl-2, two proteins involved in the control of apoptosis. Bcl-2 levels exhibited a late decrease compared with the kinetics of DNA fragmentation, whereas Bax levels increased more rapidly after CPT treatment. These results suggest that Bax plays more important role than Bcl-2 in inducing DNA fragmentation and may function upsteam of proteolytic activation of caspase-3 pathway in CPT-induced apoptosis.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.319.1-319.1
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• 2002

Yomogin. an eudesmane sesquiterpene isolated from Artemisia princeps, was found to induce apoptosis in human promyelocytic leukaemia, HL -60 cell with characteristic apoptotic features like nuclear condensation, apoptotic body formation, flipping of membrane phosphatidylserine, release of mitochondrial cytochrome c and caspase-8. -9. and -3 activation. Furthermore. early yomogin-induced cytochrome c release was not affected by the caspase inhibitor Z-VAd fmk and preceded loss of mitochondrial membrane potential. The results suggest that induction of apoptosis by yomogin may provide a pivotal mechanism for their cancer chemopreventive function.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.316.2-316.2
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• 2002

Manassantin B classified into dineolignans have been isolated from Saururus chinensis Manassantin B was found to induce apoptosis in human promyelocytic leukaemia HL -60 cells with characteristic apoptotic features like increase of nucleosomalladder. apoptotic body ormation. flipping of membrane phosphatidylserine. Manassantin B induced FAS and FAS ligand expression, and activated caspase 8 which cleaved bid to tbid in cytosol. The release of cytochrome c to sytosol was accompanied with decrease of bcl-2 protein and incresase of tbid and bax protein in mitochondria. Released xytochrome c activated caspase 9 and-3. but these effects were completely attenuated by the treatment of broad caspses ingibitor. Z-VAD fmk. These results indicate that manassatin B induce apoptosis through upregulation of FAS. caspase family and mitochondria-related proteins.

• 생명과학회지
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• 제25권8호
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• pp.849-860
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• 2015

본 연구에서는 한약재로 널리 사용되는 건칠, 유근피 및 신석 추출물의 항암 활성을 조사하였다. 생쥐 유래 정상세포(RAW 264.7 대식세포 및 C2C12 근아세포)에서는 건칠, 유근피 및 신석 단독 및 복합 처리에 의하여 유의적인 세포생존율의 억제 현상은 관찰 할 수 없었다. 그리고 건칠, 유근피 및 신석의 복합 처리는 단독 처리군에 비하여 AGS 위암세포의 생존력을 유의적으로 억제하였으나, 폐암(A549), 대장암(HCT116), 간암(Hep3B) 및 방광암(T24) 세포에서는 그 효과가 미비하였다. 아울러 이러한 AGS 위암세포 선택적 생존 억제력은 apoptosis 유도와 밀접한 연관성이 있음을 염색질의 응축 현상, DNA 단편화 및 annexin-V 염색에 의한 flow cytometry 분석을 통하여 확인하였다. 건칠, 유근피 및 신석의 복합 처리는 Fas 및 Fas legand의 발현을 증가시켰으며, XIAP, cIAP-1 및 survivin과 같은 IAP family 단백질과 anti-apoptotic Bcl-xL의 발현은 저하시켰다. 복합 처리는 또한 mitochondrial membrane potential의 손실과 caspases (-3, -8 및 -9)의 활성에 PARP 단백질의 분절화를 유도하였다. 그러나 이러한 복합 처리에 의한 AGS 세포에서 관찰된 세포독성 및 apoptosis 유도 효과는 pan-caspases inhibitor인 z-VAD-fmk의 선처리에 의하여 차단되었다. 이상의 결과는 건칠, 유근피 및 신석의 복합 처리에 의한 AGS 위암세포 선택적 apoptosis 유도가 caspase 의존적으로 일어나고 있음을 보여주는 결과이며, in vivo 모델을 이용한 후속 연구가 진행되어야 할 것이다.

• 생명과학회지
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• 제23권9호
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• pp.1118-1125
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• 2013

감귤류에 많이 함유되어 있는 naringenin은 항암화학요법제로서 중요한 가능성을 가지고 있으나 항암활성에 대한 분자생물학적 기전에 대해서는 명확히 밝혀져 있지 않다. 본 연구에서는 인체 혈구암세포인 U937 세포에서 naringenin이 유발하는 항암효과 및 항암기전을 조사하였다. Naringenin 처리에 의한 U937 세포의 증식억제는 apoptosis 유발과 연관성이 있었으며, 이러한 현상은 caspases 활성화와 밀접한 관련이 있었다. 그러나 pan-caspase inhibitor인 z-VAD-fmk의 선처리에 의하여 U937 세포에서 naringenin이 유발하는 apoptosis가 억제되는 것으로 나타났으므로 caspases가 apoptosis 유발의 중요한 조절자라는 것을 알 수 있었다. 또한 U937 세포에 naringenin을 처리하였을 경우 pro-apoptotic Bcl-2 및 anti-apoptotic Bax의 발현에는 아무런 변화가 나타나지는 않았지만 Bcl-2가 과발현된 U937/Bcl-2 세포에서 naringenin에 의한 apoptosis가 억제되었다. 하지만 small-molecule Bcl-2 inhibitor인 HA14-1 및 naringenin을 같이 처리하였을 경우에는 XIAP 발현감소, Bid 단편화 및 caspase-3 활성화를 통하여 다시 apoptosis가 유발되었다. 따라서 HA14-1 및 naringenin에 의한 apoptosis 상승효과는 death receptor-mediated apoptosis pathway를 경유한다는 것을 제시하는 결과이다.

• 생명과학회지
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• 제17권8호통권88호
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• pp.1063-1067
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• 2007

Bcl-2 family 단백질은 세포사 조절에 매우 중요한 역할을 하며 세포사 촉진 Bcl-2 family 단백질과 세포사 억제 Bcl-2 family 단백질 사이의 균형적인 상호작용이 세포의 운명을 결정하는 주요인자이다. Bcl-2 family 단백질 중 하나인 Noxa 단백질은 p53 에 의한 전사되는 단백질로 처음 발견되었다. Noxa 단백질이 어떻게 세포사를 조절하는지를 이해하기 위해 Yeast two-hybrid 방법을 통해 Noxa 단백질과 결합하는 파트너 단백질을 검색하였고 이를 통해 세포사 억제 단백질 중 하나인 Mcl-1를 발견하였다. 사람 대장암 세포주인 HCT 116에서 Noxa 단백질과 Mcl-1 단백질이 결합하는 것을 면역침전 방법을 통하여 확인하였다. HCT 116 세포주에서 Mcl-1 단백질 과다발현은 Noxa에 의한 세포사 유도를 크게 억제하였다. Noxa 단백질 과다발현에 의한 세포사 과정에서 Mcl-1 단백질이 분해되는 것을 발견하였고 이는 caspase 억제제인 z-VAD-fmk에 의해서 억제되었다. 이는 Mcl-1 단백질이 cas-pase에 의해서 분해되는 것으로 간주된다. 결론적으로, Noxa와 Mcl-1의 결합은 세포사 과정 중 caspase에 의한 Mcl-1 단백질 분해를 유도를 매개할 수 있을 것으로 추측된다.