• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.1
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• pp.121-124
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• 2008

The caspase family proteins play an important role in programmed cell death (apoptosis). To date, the expression profiles of the caspase family genes in Bombyx mori (Bm) are poorly known. In this study, we examined the expression profiles of two novel Bm caspase family genes (ice-2 and ice-5), the potential change of the mitochondrial membrane and the morphology in Bm cells after stimulation of ultraviolet (UV) irradiation. The results showed the potential change of the mitochondrial membrane occurred at 5 hours after UV irradiation treatment. Analysis of fluorescent quantitative RT-PCR demonstrated that both the ice-2 and ice-5 might be involved in UV induced apoptosis in Bm cells. Notably, after UV irradiating, expression pattern of ice-2 and ice-5 were remarkably different. The ice-2 gene was highly expressed at two time points, 0.5 and 5 hours after UV stimulating, while the expression level of ice-5 only peaked at 5 hours after UV stimulating. It indicated that apoptosis induced by UV irradiation was involved in the mitochondrial pathway and the two isoforms of Bm ice may act but play different role during the apoptosis of Bm cells.

• Toxicological Research
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• v.18 no.2
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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.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.450-464
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• 2004

Background : The FHIT (fragile histidine triad) gene is a frequent target of deletions associated with abnormal RNA and protein expression in lung cancer. Previous studies have shown FHIT gene transfer into lung cancer cell line lacking FHIT protein expression resulted in inhibition of tumor cell growth attributable to the induction of apoptosis and reversion of tumorigenecity. However, the mechanism of the tumor suppressor activity of the FHIT gene and the cellular pathways associated with its function are not completely understood. Methods : To gain insight into the biological function of FHIT, we compared the NCI-H358 cell line with its stable FHIT transfectants after treatment with cisplatin or paclitaxel. We investigated the effects of FHIT gene expression on cell proliferation, apoptosis, and activation of caspase system and Bcl-2 family. The induction of apoptosis was evaluated by using DAPI staining and flow cytometry. Activation of caspases and Bcl-2 members was evaluated by Western blot analysis. Results : A significantly increased cell death was observed in FHIT transfectants after cisplatin or paclitaxel treatment and this was attributable to the induction of apoptosis. Remarkable changes in caspases and Bcl-2 family were observed in the transfected cells as compared with the control cells after treatment with paclitaxel. Activation of caspase-3 and caspase-7 was markedly increased in cells expressing FHIT. Expression level of Bcl-2 and Bcl-xL protein was significantly decreased and that of Bax and Bad protein was significantly increased in the transfected cells. Conclusion : FHIT gene delivery into lung cancer cells results in enhanced apoptosis induced by treatment with cisplatin or paclitaxel. The data suggest that apoptosis in FHIT-expressing cells could be related to activation of caspase pathway and Bcl-2 family.

• Food Science and Biotechnology
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• v.17 no.6
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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.

• Korean Journal of Biological Psychiatry
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• v.5 no.2
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• pp.219-226
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• 1998

Cytosine arabinoside(AraC) inhibits DNA synthesis and ${\beta}$-DNA polymerase, an enzyme involved in DNA repair. This, a potent antimitotic agent, is clinically used as an anticancer drug with side effect of severe neurotoxicity. Earlier reports suggested that inhibition of neuronal survival by AraC in sympathetic neuron may be due to the inhibition of a 2'-deoxycytidine-dependent process that is independent of DNA synthesis or repair and AraC induced a signal that is triggers a cascade of new mRNA and protein synthesis, leading to apoptotic cell death in cultured cerebellar granule cells. The present study would suggest whether caspase family(ICE/CED-3-like protease) involved in AraC-induced apoptosis pathway of PC12 cells. It was observed that treatment of PC12 cells with AraC led to decrease of viability by MTT assay and morphology changes, which did not suggest that AraC induced apoptosis in PC12 cells. The mRNA of caspase-1/caspase-3 were expressed in PC12 cells constitutively, and AraC did not activate caspase family. These results suggest that caspase-1/caspase-3 may not be required for AraC-induced cell death pathway in PC12 cells.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.145-163
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• 2002

Objectives: The purpose of this investigation was to evaluate the effects of Woohwangcheongsim-won and to study the mechanism for neuronal death protection in hypoxia with Embryonic day 20 (E20) cortical cells of a rat (Sprague Dawley). Methods: E20 cortical cells were dissociated in neurobasal media and grown for 14 days in vitro (DIV). On 14 DIV, Woohwangcheongsim-won was added to the culture media for 24 hrs or 72 hrs. On 17 DIV, cells were given a hypoxic shock and further incubated in normoxia for another three days. On 20 DIV, Woohwangcheongsim-won's effects for neuronal death protection were evaluated by LDH assay, propidium iodide stain and phospho-H2AX immunostain and the mechanisms were studied by Bcl-2, Bak, Bax, caspase family, PKCα, ca1pain I. Results & Conclusions : 1. This study indicated that Woohwangcheongsim-won's effects for neuronal death protection in hypoxia were confirmed by LDH assay, propidium iodide stain and phospho-H2AX immunostain in culture method of Embryonic day 20(E20) cortical neuroblasts. 2. Woohwangcheongsim-won's mechanisms for neuronal death protection in hypoxia are to reduce the membrane damage fraction, to restrain DNA truncate, to restrain inflow of cytochrome c into cellularity caused by Bak diminution, to reduce the caspase cascade intiator caspase-8 and the effector caspase-3, to reduce the calpain I activity and to increase PKCand its activity in the membrane fraction. (J Korean Oriental Moo 2002;23(3):145～163)

• Journal of Life Science
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• v.27 no.11
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• pp.1340-1348
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• 2017

Sanguinarine is a benzophenanthridine alkaloid derived from the roots of Sanguinaria canadensis L., which is used for the purpose of treating various diseases. Although studies of anticancer activities have been performed using various cancer cell lines, the phenomenon of inducing apoptosis in cancer cells by using sanguinarine requires more research. Therefore, this study investigated the anti-cancer activities and related mechanisms of sanguinarine used with Hep3B human hepatocellular carcinoma cells in terms of the regulation of apoptosis. Sanguinarine inhibited the proliferation of Hep3B cells in a concentration-dependent manner, which was associated with the induction of apoptosis. Sanguinarine also increased the activity of caspase-3, which is a typical effector caspase, and the activities of caspase-8 and caspase-9, which are key when initiating extrinsic and intrinsic apoptosis pathways, respectively. In addition, sanguinarine increased the expression of death receptor-related genes and pro-apoptotic BAX, which belongs to the Bcl-2 family, while suppressing the expression of anti-apoptotic Bcl-2. Sanguinarine promoted the truncation of Bid and enhanced the release of cytochrome c from the mitochondria to the cytoplasm due to a loss of mitochondrial membrane potential. Furthermore, the reduction of a survival rate that was induced by sanguinarine and the induction of apoptosis disappeared with the inhibition of artificial caspase activity. Therefore, the results of the study indicated that sanguinarine-induced apoptosis in Hep3B cells involves both extrinsic and intrinsic pathways; such apoptosis is a caspase-dependent phenomenon.

• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.719-723
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• 2014

Caspases are a family of cysteine proteases that play an important role in the apoptotic pathway. Caspase-6 is an apoptosis effector that cleaves a variety of cellular substrates. The active form of the enzyme is required for use in research. However, it has been difficult to obtain sufficient quantities of active caspase-6 from Escherichia coli. In the present study, we constructed a caspase-6 with a 23-amino-acid deletion in the pro-domain. This engineered enzyme was expressed as a soluble protein in E. coli and was purified using affinity resin. In vitro enzyme assay and cleavage analysis revealed that the engineered active caspase-6 protein had characteristics similar to those of wild-type caspase-6. This novel method can be a valuable tool for obtaining active caspase-6 that can be used for screening caspase-6-specific substrates, which in turn can be used to elucidate the function of caspase-6 in apoptosis.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.1003-1010
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• 2002

Caspase 3, a member of cysteine protease family, is well known as a major apoptosis effector and is involved in cell death as a result of ischemic diseases such as stroke and myocardial infarction, therefore the inhibition of caspase 3 may protect those apoptotic cell damages. During the high-throughput screening of the compounds from the Korea Chemical Bank, berberine derivatives (A and B), an isoquinoline alkaloid, have been identified as potential inhibitors for caspase 3. Based on this finding we carried out molecular modeling study to identify the pharmacophoric elements of berberine structure which interact with a substrate-recognition binding site of caspase 3 and came up with several novel scaffolds. In this report, we will discuss the molecular modeling, syntheses and the enzyme inhibitory activities of these novel compounds.

• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.255-263
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• 2019

Glycyrrhizae radix is one of the most frequently prescribed ingredients in Oriental medicine, and Glycyrrhizae radix extract has been shown to exert anti-cancer effects. However, the cellular and molecular mechanisms of programed cell death (apoptosis) by Glycyrrhizae radix are poorly defined. In the present study, it was examined the molecular mechanisms of apoptosis by water extracts of Glycyrrhizae radix (GRW) in human bladder T24 cancer cells. It was found that GRW could inhibit the cell growth of T24 cells in a concentration-dependent manner, which was associated with the induction of apoptotic cell death, as evidenced by the formation of apoptotic bodies, DNA fragmentation and increased populations of annexin-V positive cells. The induction of apoptotic cell death by GRW was connected with an up-regulation of pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic proteins (Bcl-2 and Bcl-xL), and inhibition of apoptosis family proteins (XIAP, cIAP-1 and cIAP-2). In addition, apoptosis-inducing concentrations of GRW induced the activation of caspase-9, an initiator caspase of the mitochondrial-mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of PARP. GRW also induced apoptosis via a death receptor-mediated extrinsic pathway by caspase-8 activation, resulting in the down-regulation of total Bid and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. Taken together, the present results suggest that GRW may be a potential chemotherapeutic agent for the control of human bladder cancer cells.