• 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.

• Animal cells and systems
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• v.5 no.2
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• pp.145-151
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• 2001

p62 is a phosphotyrosine-independent ligand of the SH2 domain of $p56^{Ick}$, a T-cell specific Src family tyrosine kinase. Recently p62 has been shown to interact with a number of proteins, such as $PKC\varsigma$ and ubiquitin, and implicated in important cellular functions such as cell proliferation. Since the two p62 interacting proteins, $p56^{Ick}$ and $PKC\varsigma$, have been reported to play roles in cell death, 1 have addressed the potential role of p62 during apoptosis in Jurkat cells in this study. Herein 1 show that p62 was specifically cleaved into two peptides by a caspase-3-like activity during Fas-receptor mediated apoptosis in Jurkat cells. This cleavage generated two fragments with molecular weights of about 35 kDa that differed in subcellular localizations. The N-terminal cleaved fragment was present in the detergent-insoluble fraction whereas the C-terminal fragment was found in the detergent-soluble fraction. In addition, the C-terminal fragment appeared to be subjected to further degradation as apoptosis prolonged. Moreover, overexpression of p62 in Jurkat cells attenuated the Fas receptor mediated apoptosis, suggesting that p62 is involved in apoptotic signal transduction pathway in lymphocytes.

• Toxicological Research
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• v.19 no.3
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• pp.197-203
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• 2003

Apicidin, a histone-deacetylase inhibitor, has been successfully used to inhibit the growth of cancer cells. In this study, the apoptotic potential and mechanistic insights of apicidin were investigated in human myeloid leukemia U937 cells. Treatment of U937 cells with apicidin resulted in a decrease of cell viability with apoptotic characteristics, including chromatin condensation and ladder-pattern fragmentation of genomic DNA. Apicidin converted the procaspase-3 protease to catalytically active effector protease, resulting in subsequent cleavage of poly (ADP-ribose) polymerase (PARP) and inhibitor of caspase-activated deoxyribonuclease (ICAD). In addition, apicidin induced the activation of caspase-9 protease and the cytosolic release of mitochondrial cytochrome c with mitochon-drial membrane potential transition. Moreover, apicidin transiently increased the expression of Fas and Fas ligand proteins. Taken together, the results suggest that apicidin induces apoptosis of U937 cells through activation of intrinsic caspase cascades and Fas/FasL system with mitochondrial dysfunction.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2001.10a
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• pp.204-207
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• 2001

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2005.11a
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• pp.82-83
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• 2005

• Clinical and Experimental Reproductive Medicine
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• v.46 no.4
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• pp.152-165
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• 2019

Objective: This study aimed to examine the effect of vitrification on apoptosis and survival in human preantral follicles after thawing. Methods: This experimental study was conducted at an acute tertiary care hospital from March 2012 to April 2013. Ovaries were sliced into 5 × 5 × 1-mm pieces and divided into the following three groups: preantral follicle isolation, ovarian tissue vitrification-warming followed by follicle isolation, and immunohistochemistry of fresh ovarian tissue. For statistical analyses, the Student t-test, chi-square test, Kruskal-Wallis test, and Kaplan-Meier survival analysis were used. Results: A total of 161 preantral follicles (70% secondary) were collected from ovarian cortex tissue of six women between 30 and 37 years of age who underwent oophorectomy due to cervical cancer or breast cancer. There were no significant differences in the follicular morphology of fresh preantral follicles and vitrified follicles after thawing. The mean Fas ligand (FasL) mRNA expression level was 0.43 ± 0.20 (relative to β-actin) in fresh preantral follicles versus 0.51 ± 0.20 in vitrified follicles (p= 0.22). The mean caspase-3 mRNA expression level in fresh preantral follicles was 0.56 ± 0.49 vs. 0.27 ± 0.21 in vitrified follicles (p= 0.233). One vitrified-thawed secondary follicle grew and developed to an antral follicle within 6 days of culture. Conclusion: Vitrification did not affect preantral follicle morphology or mRNA expression of the apoptosis markers FasL and caspase-3. Further studies are required to establish whether vitrification affects the outcomes of in vitro culture and the maturation of preantral follicles.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.1
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• pp.29-31
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• 2003

It is well known that different expression of Apo-1/Fas (CD95) plays important roles in various tumors and hepatocellular carcinoma (HCC) pathogenesis. Apo-1/Fas mediated apoptosis is one of the important pathways of apoptosis and is known to mediate apoptotic cell death by fas ligand (FasL). To examine the possible relationship between Apo-1/Fas gene polymorphism and HCC susceptibility, MvaI restriction fragment length polymorphism (RFLP) of Apo-1/Fas gene was examined in 94 Korean HCC patients and 240 control subjects. No statistically significant difference in the genotypic distribution and allelic frequencies was found between the control and the HCC. It is, therefore, concluded that Apo-1/Fas gene polymorphism is not associated with HCC susceptibility. Further studies are needed in order to clarify the relationships between genotypes of Apo-1/Fas gene and HCC pathogenesis.

• Radiation Oncology Journal
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• v.20 no.3
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• pp.246-252
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• 2002

Purpose : It has been recognized that interaction of the Fas : Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. Materials and Method : Mice with mutations in Fas, $MRL/Mpj-Fas^{Ipr}$, and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, $Bcl-X_L,\;and\;Bcl-X_S$ were also analyzed by Western blotting. Results : At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in $MRL/Mpj-Fas^{Ipr}$. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and $MRL/Mpj-Fas^{Ipr}$ mice were $52.3{\pm}7.8\%\;and\;8.0{\pm}8.6\%$, respectively (p<0.05). The expression of apoptosis regulating molecules, p53, $Bcl-X_L\;and\;Bcl-X_S$, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, $Bcl-X_L$ with a peak level of 3.3-fold at 12 h, and $Bcl-X_S$ with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in $MRL/Mpj-Fas^{Ipr}$ mice, the expression levels of p53, Bcl-2, Bax, $BCl-X_L\;and\;BCl-X_S$ showed no significant change. Conclusion : The level of radiation-induced apoptosis was lower in Fas mutated mice, Ipr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the Ipr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.145-149
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• 2003

Background: Apoptosis has been implicated in pathogenesis of various disease. Apo-1/Fas (CD95) is one of the main pathway of apoptosis. To examine the possible relationship between Apo-1/Fas (CD95) and primary knee osteoarthritis, MvaI restriction length polymorphism (RFLP) in human Apo-1/Fas (CD95) gene was assessed. Methods: Genotype and allele frequencies in promoter region in the Apo-1/Fas (CD95) gene were studied by PCR-RFLP in 226 Korean controls and 148 Korean patients with primary knee osteoarthritis. Results: No statistically significant difference in the genotypic distribution and allelic frequencies was found between the control and the knee oateoarthritis patients. But in the severe grade (grade 3, 4) Kellgren-Lawrence score patients, the frequency of $MvaI^*1$ (G) allele was significantly decreased (P=0.0392) and the of $MvaI^*2$ (A) allele frequency was significantly increased (P=0.0473) compared to the normal controls. Conclusion: Apo-1/Fas (CD95) gene polymorphism is a part a determinant factor of severity in knee osteoarthritis, the patients with $MvaI^*2$ (A) allele is more severe radiologic progression. Further substantiation studies are needed in larger patient samples and various other apoptosis related genes to elucidate the mechanism of osteoarthritis, including the Fas ligand gene analysis.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.59-66
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• 2006

Background: CM1 (Centrocyte/-blast Marker I) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on a subpopulation of centroblasts and centrocytes of human germinal center (GC) B cells. Burkitt lymphoma (BL) is a tumor consisting of tumor cells with the characteristics of GC B cell. Previously we reported that CM1 ligation with anti-CM1 mAb induced apoptosis in Ramos $(IgM^{high})$ and Raji $(IgM^{low})$ cells. Methods & Results: In the present study, we observed that CM1 ligation with anti-CM1 mAb induced Fas ligand and Fas expression in Ramos cells, but not in Raji cells. Furthermore, anti-Fas blocking antibody, ZB4, blocked CM1-mediated apoptosis effectively in Ramos cells, but not in Raji cells. Increased mitochondrial membrane permeabilization, which was measured by $DiOC_6$, was observed only in Raji cells. In contrast to no significant change of Bax known as pro-apoptotic protein, anti-apoptotic protein Bcl-2 was significantly decreased in Raji cells. In addition, we observed that CM1 ligation increased release of mitochondrial cytochrome c and upregulated caspase-9 activity in Raji cells. Conclusion: These results suggest that apoptosis induced by CM1-ligation is mediated by Fas-Fas ligand interaction in Ramos cells, whereas apoptosis is mediated by down-regulation of Bcl-2 and subsequent decrease of mitochondrial membrane potential in Raji cells.