• Food Science and Biotechnology
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• 제17권6호
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• pp.1305-1309
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• 2008

Baicalein, one of the major flavonoid in Scutellaria baicalensis, has been known for its effects on proliferation and apoptosis of many tumor cell lines. Most biological effects of baicalein are thought to be from its antioxidant and prooxidant activities. In this report, baicalein was found to induce apoptosis in HL60 human promyelocytic leukemia cell line. Baicalein treatment induced DNA fragmentation and typical morphological features of apoptosis. To elucidate the mechanism of baicalein-induced apoptosis, the activities of the members of caspase family were measured. Interestingly caspase 2, 3, and 6 were significantly activated whereas caspase 1, 8, and 9 were not activated, suggesting selective involvement of specific caspases. Further, treatment with caspase inhibitors also supports the involvement of caspase 2 in apoptosis process. Although it has been reported that baicalein can induce apoptosis through many caspase pathways, the present study indicates that caspase 2 not caspase 9 pathway may be the important step in apoptosis on HL60 cell line.

• 생명과학회지
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• 제21권12호
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• pp.1678-1688
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• 2011

다양한 식용식물에 함유되어 있는 것으로 알려진 phenolic acids의 일종인 p-coumaric acid의 항암활성을 규명하고자, 인체 급성백혈병 T 세포주인 Jurkat T 세포에 대한 p-coumaric acid의 에폽토시스 유도기전을 조사하였다. Jurkat T 세포를 p-coumaric acid (50-$150{\mu}M$)로 처리한 결과, 세포독성, 에폽토시스-관련 DNA fragmentation, 및 pro-apoptotic multidomain Bcl-2 family member인 Bak의 활성화, ${\Delta}{\psi}m$ loss, caspase-9, -3, -7, 및 -8의 활성화, 그리고 PARP 분해 등의 여러 에폽토시스-관련 생화학적 현상들이 농도의존적으로 나타났다. 그러나 이러한 에폽토시스-관련 생화학적 현상들은 Jurkat T 세포에 anti-apoptotic Bcl-2 단백질을 과발현할 경우에는 나타나지 않았다. 또한 p-coumaric acid처리에 의해 유도되는 Jurkat T 세포의 에폽토시스에는 necrosis가 수반되지 않는 것으로 확인되었다. Jurkat T 세포를 pan-caspase inhibitor인 z-VAD-fmk를 전처리할 경우, p-coumaric acid 처리에 의해 유도되는 apoptotic sub-$G_1$ peak는 차단되어 나타나지 않았으나 ${\Delta}{\psi}m$ loss는 여전히 나타났는데, 이는 p-coumaric acid처리에 의한 에폽토시스의 유도에 caspase cascade 활성화가 필수적이며 ${\Delta}{\psi}m$ loss의 downstream 현상임을 나타낸다. 한편, FADD 및 caspase-8을 함께 발현하는 Jurkat T 세포주 A3, FADD-결손 Jurkat T 세포주 I2.1, 그리고 caspase-8-결손 Jurkat T 세포주 I9.2의 p-coumaric acid의 세포독성에 대한 감수성은 서로 유사하게 나타났는데, 이는 p-coumaric acid처리에 의한 에폽토시스의 유도가 Fas와 FasL간의 상호작용에 의해 개시되지 않음을 시사한다. p-Coumaric acid의 세포독성은 Jurkat T 세포에 비해 인체 정상 말초혈액 T 세포에서 훨씬 낮게 나타났다. 이러한 결과들은 p-coumaric acid 처리에 의해 유도되는 Jurkat T 세포의 에폽토시스가 Bak 활성화, ${\Delta}{\psi}m$ loss, caspase-9, -3, -7, 및 -8로 이루어진 caspase cascade의 활성화, 그리고 PARP 분해에 의해 유도되며, 또한 anti-apoptotic 단백질인 Bcl-2의 과발현에 의해서 음성적으로 조절됨을 나타낸다.

• Journal of Ginseng Research
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• 제45권2호
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• pp.295-304
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• 2021

Background: Acute promyelocytic leukemia (APL) is a hematopoietic malignancy driven by promyelocytic leukemia-retinoic acid receptor A (PML-RARA) fusion gene. The therapeutic drugs currently used to treat APL have adverse effects. 20(S)-ginsenoside Rh2 (GRh2) is an anticancer medicine with high effectiveness and low toxicity. However, the underlying anticancer mechanisms of GRh2-induced PML-RARA degradation and apoptosis in human APL cell line (NB4 cells) remain unclear. Methods: Apoptosis-related indicators and PML-RARA expression were determined to investigate the effect of GRh2 on NB4 cells. Z-VAD-FMK, LY294002, and C 87, as inhibitors of caspase, and the phosphatidylinositol 3-kinase (PI3K) and tumor necrosis factor-α (TNF-α) pathways were used to clarify the relationship between GRh2-induced apoptosis and PML-RARA degradation. Results: GRh2 dose- and time-dependently decreased NB4 cell viability. GRh2-induced apoptosis, cell cycle arrest, and caspase3, caspase8, and caspase9 activation in NB4 cells after a 12-hour treatment. GRh2-induced apoptosis in NB4 cells was accompanied by massive production of reactive oxygen species, mitochondrial damage and upregulated Bax/Bcl-2 expression. GRh2 also induced PML/PML-RARA degradation, PML nuclear bodies formation, and activation of the downstream p53 pathway in NB4 cells. Z-VAD-FMK inhibited caspase activation and significantly reversed GRh2-induced apoptosis and PML-RARA degradation. GRh2 also upregulated TNF-α expression and inhibited Akt phosphorylation. LY294002, an inhibitor of the PI3K pathway, enhanced the antitumor effects of GRh2, and C 87, an inhibitor of the TNF-α pathway, reversed NB4 cell viability, and GRh2-mediated apoptosis in a caspase-8-dependent manner. Conclusion: GRh2 induced caspase-dependent PML-RARA degradation and apoptosis in NB4 cells via the Akt/Bax/caspase9 and TNF-α/caspase8 pathways.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3289-3294
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• 2016

Naringin, a bioflavonoid found in Citrus seeds, inhibits proliferation of cancer cells. The objectives of this study were to investigate the mode and mechanism(s) of hepatocellular carcinoma HepG2 cell death induced by naringin. The cytotoxicity of naringin towards HepG2 cells proved dose-dependent, measured by MTT assay. Naringin-treated HepG2 cells underwent apoptosis also in a concentration related manner, determined by annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) employing flow cytometry. Mitochondrial transmembrane potential (MTP) measured using 3,3'-dihexyloxacarbocyanine iodide ($DiOC_6$) and flow cytometer was reduced concentration-dependently, which indicated influence on the mitochondrial signaling pathway. Caspase-3, -8 and -9 activities were enhanced as evidenced by colorimetric detection of para-nitroaniline tagged with a substrate for each caspase. Thus, the extrinsic and intrinsic pathways were linked in human naringin-treated HepG2 cell apoptosis. The expression levels of pro-apoptotic Bax and Bak proteins were increased whereas that of the anti-apoptotic Bcl-xL protein was decreased, confirming the involvement of the mitochondrial pathway by immunoblotting. There was an increased expression of truncated Bid (tBid), which indicated caspase-8 proteolysis activity in Bid cleavage as its substrate in the extrinsic pathway. In conclusion, naringin induces human hepatocellular carcinoma HepG2 cell apoptosis via mitochondria-mediated activation of caspase-9 and caspase-8-mediated proteolysis of Bid. Naringin anticancer activity warrants further investigation for application in medical treatment.

• 대한의생명과학회지
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• 제26권2호
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• pp.57-65
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• 2020

Excessive drinking of alcohol is known to be one of the main causes of various neurological diseases, such as Alzheimer's disease. Scopoletin is known to have anti-inflammatory and antioxidative properties, and to protect nerve cells. This study examined whether scopoletin inhibits the alcohol-induced apoptosis of primary hippocampal neurons, and how scopoletin regulates several factors associated with the caspase-mediated pathway. To achieve this, the cell viability and apoptosis rate of primary hippocampal neurons were measured by Cell Counting Kit-8 and flow cytometry, respectively. Apoptosis-related protein expressions (Bax, Bid, caspase-3, caspase-9, and Poly (ADP-ribose) polymerase (PARP)) were analyzed by Western blotting, and the ANOVA method was used to confirm the significance of the measured results. As a result, scopoletin inhibited the expressions of alcohol-induced apoptosis and apoptosis-related proteins in primary hippocampal neurons. These results suggest that down-regulation of Bid, Bax, and cleaved caspase-9 expression induced by scopoletin down-regulates the expression of cleaved caspase-3, inhibits the expression of cleaved PARP, and finally, inhibits mitochondrial apoptotic pathways. The study suggests that scopoletin is worth developing as a candidate for neuroprotective agent.

• 운동영양학회지
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• 제13권2호
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• pp.109-113
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• 2009

The objective of this study was to compare the effects of a combined treatment consisting of an isoflavone diet and aerobic exercise on the Caspase 9 levels, and Bcl-2 levels during menopause, using 30 S.D ovariectomized rats as a model, over 12 weeks. The ovariectomized rats were divided into 4 experiment groups, with 8 rats in each group, as follows: (1) General diet group (GD, n=8), (2) Isoflavone diet group (ID, n=8), (3) General diet + Exercise group (GEX, n=8), (4) Isoflavone diet + Exercise group (IEX, n=8). The findings of this study were as follows: 1. Combined treatment consisting of an isoflavone diet and regular exercise resulted in a significant reduction in the expression of caspase-9 proteins (p<0.05), and a significant increase in the expression of Bcl-2 proteins (P<0.001). In addition, apoptotic cells were more decreased (p<0.001) in GEX and IEX group. This also suggests that cardiovascular disease in postmenopausal women might be prevented or inhibited to exert positive apoptotic inhibitory effects by increasing Bcl-2 protein expression within aortic tissues during vascular movement and decrease caspase-9 protein.

• 생명과학회지
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• 제27권11호
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• pp.1340-1348
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• 2017

Sanguinarine은 다양한 목적으로 사용되고 있는 Sanguinaria canadensis L.의 뿌리에서 유래된 benzophenanthridine alkaloid 계열 물질중의 하나이다. 그동안 sanguinarine의 다양한 약리학적인 효능이 알려져 왔고, 항암활성에 대한 연구도 여러 암세포들을 대상으로 수행되어 왔다. 그러나 sanguinarine에 의한 암세포의 apoptosis 유도에 대한 현상은 여전히 많은 부분에서 연구의 대상으로 남아 있다. 본 연구는 Hep3B 인체 간암세포를 대상으로 sanguinarine의 항암활성에 대한 추가적인 자료를 제시하기 위하여 수행되었다. 본 논문의 결과에 의하면, sanguinarine은 처리 농도 의존적으로 Hep3B 세포의 증식을 억제하였으며, 이는 apoptosis 유도와 연관성이 있었다. Sanguinarine은 두 가지 apoptosis 경로인 extrinsic 및 intrinsic 경로의 개시 initiator caspase인 caspase-8 및 caspase-9 뿐만 아니라 대표적인 effector caspase인 caspase-3의 활성을 증가시켰고, caspase-3의 기질인 PARP의 분절을 유발하였다. 아울러 sanguinarine은 DR-related 유전자들의 발현을 부분적으로 증가시켰으며, Bcl-2 family에 속하는 pro-apoptotic Bax의 발현을 증가시킨 반면, anti-apoptotic Bcl-2의 발현은 억제시켰다. 또한 sanguinarine은 Bid의 truncation을 촉진하였고, MMP의 소실에 따른 cytochrome c를 미토콘드리아에서 세포질로의 이동을 증가시켰다. 그리고 sanguinarine에 의한 apoptosis 유도 및 세포 증식율 억제 현상이 caspase의 활성을 인위적으로 억제하였을 경우, 모두 사라졌다. 따라서 sanguinarine에 의하여 유도하는 Hep3B 세포의 apoptosis 유발에는 caspase 의존적으로 extrinsic 및 intrinsic 경로가 모두 관여하고 있음을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1771-1779
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• 2015

Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide. Presently, targeted therapy via monoclonal antibodies to specific tumor-associated antigens is being continuously developed. Hep88 mAb has proven to exert tumoricidal effects on the HepG2 cell via a paraptosis-like morphology. To verify the pathway, we then demonstrated downstream up-regulation of caspase-3, caspase-8 and caspase-9, assessingmRNA expression by real-time PCR and associated enzyme activity by colorimetric assay. Active caspase-3 determination was also accomplished by flow cytometry. Active caspase-3 expression was increased by Hep88 mAb treatment in a dose-and time-dependent manner. All of the results indicated that Hep88 mAb induced programmed cell death in the HepG2 cell line from paraptosis-like to apoptosis by downstream induction of caspases. These conclusions imply that Hep88mAb might be a promising tool for the effective treatment of HCC in the future.

• Toxicological Research
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• 제18권2호
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• pp.183-190
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• 2002

The mechanism by which catechin-mediated cytotoxicity against tumor cells remains to be elusive. To elucidate the mechanical mights of anti-tumor effects, (-)epigallocatechin-gallate (EGCG) of catechin was applied to human prostate cancer DU 145 cells. Cell viability was measured by crystal violet staining. Cell lysates were wed to measure the catalytic activity of caspases by using fluorogenic peptide: Ac-DEVD-AMC for caspase-3 protease, Z-IETD-AFC for caspase-8 protease, Ac-LEHD-AFC for caspase-9 protease as substrates. The equal amounts of protein from cell lysate was separated on SDS-PAGE and analyzed by western blotting with anti-Fas antibody, anti-FasL antibody, anti-BCL2 antibody and anti-Bax antibody. (-)EGCG induced the death of DUl45 cells, which was revealed as apoptosis shown by DNA fragmentation. (-)EGCG induced the activation of caspase family cysteine proteases including caspase-3, -8 and -9 proteases in DU145 cells. Also, (-)EGCG increased the expression of Fas and Fas ligand (FasL) protein in DU145 colls. The expression level of BCL2 was decreased in (-)EGCG treated DU145 cells, whereas Bax protein was increased in a time-dependent manner. We suggest that (-)EGCG-induced apoptosis of DU145 cells is mediated by signaling pathway involving caspase family cysteine protease, mitochondrial BCL2-family protein and Fas/FasL.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1833-1837
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• 2015

An aristolactam-type alkaloid, isolated from Orophea enterocarpa, is enterocarpam-III (10-amino-2,3,4,6-tetramethoxyphenanthrene-1-carboxylic acid lactam). It is cytotoxic to various human and murine cancer cell lines; however, the molecular mechanisms remain unclear. The aims of this study were to investigate cytotoxic effects on and mechanism (s) of human cancer cell death in human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells compared to normal murine fibroblast NIH3T3 cells. Cell viability was determined by MTT assay to determine $IC_{10}$, $IC_{20}$ and $IC_{50}$ levels, reactive oxygen species (ROS) production with 2',7'-dichlorohydrofluorescein diacetate and the caspase-3, -8 and -9 activities using specific chromogenic (p-nitroaniline) tetrapeptide substrates, viz., DEVD-NA, IETD-NA and LEHD-NA and employing a microplate reader. Mitochondrial transmembrane potential (MTP) was measured by staining with 3, 3'-dihexyloxacarbocyanine iodide ($DiOC_6$) and using flow cytometry. The compound was cytotoxic to HepG2 and MDA-MB-231 cells with the $IC_{50}$ levels of $26.0{\pm}4.45$ and $51.3{\pm}2.05{\mu}M$, respectively. For murine normal fibroblast NIH3T3 cells, the $IC_{50}$ concentration was $81.3{\pm}10.1{\mu}M$. ROS production was reduced in a dose-response manner in HepG2 cells. The caspase-9 and -3 activities increased in a concentration-dependent manner, whereas caspase-8 activity did not alter, indicating the intrinsic pathway activation. Enterocarpam-III decreased the mitochondrial transmembrane potential (MTP) dose-dependently in HepG2 cells, suggesting that the compound induced HepG2 cell apoptosis via the mitochondrial pathway. In conclusion, enterocarpam-III inhibited HepG2 and MDA-MB-231 cell proliferation and induced human HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway and induction of caspase-9 activity.