• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1063-1067
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• 2007

The Bcl-2 family proteins play critical roles in regulation of apoptosis, and the balanced interaction of pro- and anti-death members is a key factor in determining the cell fate. Noxa, a BH3-only Bcl-2-family member, has been originally identified as a target gene of p53. To understand the mechanism by which human Noxa (hNoxa) regulates the cell death, we screened the hNoxa binding partner using the yeast two hybrid screening and found that anti-death protein Mcl-1 binds to hNoxa. The binding of hNoxa to Mcl-1 was confirmed by immunoprecipitation in human colon cancer cell line HCT 116 cells. Mcl-1 significantly inhibited the hNoxa-induced cell death in HCT 116 cells. During the cell death induced by hNoxa, Mcl-1 protein was degraded. Its degradation was inhibited by z-VAD-fmk, a pancaspase inhibitor, suggesting caspase is responsible for Mcl-1 degradation in response to hNoxa. Together, the results indicate that hNoxa binds to Mcl-1 that is degraded by cas-pases during hNoxa-induced cell death.

• Korean Journal of Pharmacognosy
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• v.47 no.3
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• pp.197-203
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• 2016

Decursin is a major component of the root of Angelica gigas(Umbelliferae), which has been traditionally used in Korea as a tonic and to treat anemia, hemiplegia, and women's diseases. The objective of this study is to identify the anti-cancer mechanism induced by decursin on apoptosis of human leukemia and lymphoma cells. Cytotoxicity of decursin on U937, HL-60, MOLT-4, THP-1 cells showed the significant effects. First of all, $IC_{50}$ of decursin on four cell lines was 27.1, 32.4, 17.4, $15.1{\mu}M$, respectively. So $IC_{50}$ in THP-1 cells was the smallest among 4 cell lines treated with decursin($15.1{\mu}M$). In order to understand the apoptosis-mechanism by decursin, we examined the gene expression of bcl-2(anti-apoptotic), bax(pro-apoptotic) and p53(tumor suppressor)after treating the THP-1 cells with decursin(10, 50 and $100{\mu}M$). It was found bcl-2 gene was decreased dose dependently, the expression level of bax gene of THP-1 cells treated with $100{\mu}M$ of decursin was about 3 times higher than those of control, and p53 gene was increased In the same concentration($100{\mu}M$), p53 gene was increased dose dependent manner. In protein express, bcl-2 and p53 protein showed a tendency to decrease. bax was increased about 4 fold. Therefore decursin is a useful chemotherapeutic agent against leukemia.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.759-766
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• 2004

In the present study, we investigated the effects of aqueous extract of the healthful decoction utilizing Phellinus linteus (HDPL) on the cell growth of human lung carcinoma tumor cell line A549. Exposure of A549 cells to HDPL resulted in growth inhibition and induction of apoptosis in a dose-dependent manner as measured by hemocytometer counts, fluorescence microscopy and flow cytometric analysis. This increase in apoptosis was associated with inhibition and/or degradation of apoptotic target proteins such as poly(ADP-ribose) polymerase (PARP), b-catenin and phospholipase C- 1 (PLC- 1) protein. HDPL treatment induced the down-regulation of anti-apoptotic Bcl-2 expression, an anti-apoptotic gene, however, the level of Bax. a pro-apoptotic gene, was increased by HDPL treatment. In addition, HDPL-induced apoptotis of A549 cells was connected with activation of caspase-3 and caspase-9 protease in a dose-dependent manner, however, the levels of inhibitor of apoptosis proteins family were remained unchanged. Taken together, these results indicated that the anti-proliferative effects of HDPL were associated with the induction of apoptotic cell death through regulation of several major growth regulatory gene products such as Bcl-2 family expression and caspase protease activity, and HDPL may have therapeutic potential in human lung cancer.

• Development and Reproduction
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• v.14 no.2
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• pp.83-89
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• 2010

Apoptosis is a crucial mechanism for the proper regulation of homeostasis. BCL-2 family proteins are key molecules which control cellular survival and apoptosis. MCL-1 (myeloid cell leukemia-1) is a pro-survival member of BCL-2 family that promotes the survival of cells, and is highly expressed in diverse cancers including ovarian cancer, leukemia, and cervical cancer. Previously we identified IEX-1 (immediate early response gene X-1) as a binding partner of MCL-1. In the present study, we demonstrated that overexpression of IEX-1 induced apoptosis of ovarian cancer cells. Moreover, IEX-1 significantly attenuated the pro-survival function of MCL-1 in these cells. Also, IEX-1-induced cell death activity was able to be modulated by changes in the expression level of MCL-1. Thus, these results suggest that both IEX-1 and MCL-1 modulate each other's function controlling cellular survival and death and the inhibitory activity of IEX-1 toward MCL-1 may be applied for the development of chemotherapeutics.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3131-3138
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• 2016

Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.89-96
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• 2002

The importance of apoptosis in normal development and pathogenesis has been well recognized, and explosive progress towards dissecting its commitment step has been made during the past decade. Mitochondria, Apaf-1, caspase, and bcl-2 family members play central roles in the commitment step. However, it is still unclear how upstream cell survival pathways regulate apoptosis. It is also unknown whether the bcl-2 family members have any effect on the upstream survival pathways. We have demonstrated that the anti-apoptotic gene product bcl-2 greatly induces expression of the tissue inhibitor of metalloproteinase-1 (TIMP-1) in human breast epithelial cells. Surprisingly, we found that TIMP-1, like bcl-2, is a potent inhibitor of apoptosis induced by a variety of stimuli. Functional studies indicate that TIMP-1 inhibits a classical apoptotic pathway mediated by caspases, and that focal adhesion kinase (FAK)/Pl 3-kinase and mitogen activated protein kinase (MAPK) are critical for TIMP- 1 -mediated cell survival. We also showed specific association of TIMP-1 with the cell surface. Consistently, a 150-H)a surface protein was identified in MCF10A cells that specifically binds TIMP-1. Taken together, we hypothesize that TIMP-I binding on the cell surface induces a cell survival pathway that regulates the common apoptosis commitment step. The results of these studies will address a new paradigm in the regulation of apoptosis by an extracellular molecule TIMP-1, and also greatly enhance our understanding of TIMP-1's pleiotropic activity in many physiological and pathological processes. This information may also be useful in designing more rational therapeutic interventions aimed at modulating the anti-apoptotic activity of TIMP-1 .

• YAKHAK HOEJI
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• v.45 no.4
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• pp.426-430
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• 2001

Cells are eliminated in a variety of physiological settings by apoptosis, a genetically encoded process of cellular suicide. Bak, a member of the Bcl-2 protein family, accelerates apoptosis by an unknown mechanism. We have found a novel cDNA encoding a 101 amino acid protein possessing a Bak-like in our full-length cDNA bank. Bak-like shares the conserved domains BHI and 2 with other proapoptotic proteins but lacks the BH3 domain. Bak-like is expressed in a wide variety of tissues. Like Bak, Bak-like gene product primarily enhances apoptotic cell death following an appropriate stimulus.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2133-2139
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• 2014

4-Methylsulfinyl-3-butenyl isothiocyanate (MTBITC) found in the radish (Raphanus sativus L.), is a wellknown anticancer agent. In this study, the mechanisms of the MTBITC induction of cell apoptosis in human A549 lung cancer cells were investigated. Our PI staining results showed that MTBITC treatment significantly increased the apoptotic sub-G1 fraction in a dose-dependent manner. The mechanism of apoptosis induced by MTBITC was investigated by testing the change of mitochondrial membrane potential (${\Delta}{\Psi}m$), the expression of mRNAs of apoptosis-related genes by RT-PCR, and the activities of caspase-3 and -9 by caspase colorimetric assay. MTBITC treatment decreased mitochondrial membrane potential by down-regulating the rate of Bcl-2/Bax and Bcl-xL/Bax, and activation of caspase-3 and -9. Therefore, mitochondrial pathway and Bcl-2 gene family could be involved in the mechanisms of A549 cell apoptosis induced by MTBITC.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.43-50
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• 2013

Palmitic acid (PAM), one of the most common saturated fatty acid (SFA) in animals and plants, has been shown to induce apoptosis in exocrine pancreatic AR42J cells. In this study, we investigated cellular mechanisms underlying protective effects of oleic acid (OLA) against the lipotoxic actions of PAM in AR42J cells. Exposure of cells to long-chain SFA induced apoptotic cell death determined by MTT cell viability assay and Hoechst staining. Co-treatment of OLA with PAM markedly protected cells against PAM-induced apoptosis. OLA significantly attenuated the PAM-induced increase in the levels of pro-apoptotic Bak protein, cleaved forms of apoptotic proteins (caspase-3, PARP). On the contrary, OLA restored the decreased levels of anti-apoptotic Bcl-2 family proteins (Bcl-2, Bcl-xL, and Mcl-1) in PAM-treated cells. OLA also induced up-regulation of the mRNA expression of Dgat2 and Cpt1 genes which are involved in triacylglycerol (TAG) synthesis and mitochondrial ${\beta}$-oxidation, respectively. Intracellular TAG accumulation was increased by OLA supplementation in accordance with enhanced expression of Dgat2 gene. These results indicate that restoration of anti-apoptotic/pro-apop-totic protein balance from apoptosis toward cell survival is involved in the cytoprotective effects of OLA against PAM-induced apoptosis in pancreatic AR42J cells. In addition, OLA-induced increase in TAG accumulation and up-regulation of Dgat2 and Cpt1 gene expressions may be possibly associated in part with the ability of OLA to protect cells from deleterious actions of PAM.

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.17-23
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• 2005

In the present study, we expected the anti-tumor effect by combined treatment of arsenic trioxide and interferon (IFN)-${\alpha}$ on murine Lewis lung carcinoma (LL2) cells through in vivo study. As a experimental model, LL2 cells ($1{\times}10^{6}$/mouse) were injected subcutaneously into the back region of mice. When the tumor volume reached $100mm^3$, mice were treated with 1 mg/kg arsenic trioxide, 50000 IU IFN-${\alpha}$, or arsenic trioxide and IFN-${\alpha}$. The development of tumor cells was significantly inhibited by combined treatment with arsenic trioxide and IFN-${\alpha}$. In arsenic trioxide and IFN-${\alpha}$ treated group, apoptotic index was reached a peak valve at 48 hr after the treatment and it was restored to approximately the control level at 8 days. Also, positive signals of Bax and Bad were increased at 48 to 96 hr and decreased at 8 day. Whereas, positive cells of Bcl-2 were steadily decreased at 12 to 48 hr and restored to the background level at 8 days. Our data showed that immunoreactivity of Bcl-2 was decreased at 12 to 48 hr, while positive signals of Bax and Bad were increased in accordance with apoptotic index at these times. In conclusion, our results suggest that the combined treatment with arsenic trioxide and IFN-${\alpha}$ significantly inhibited the growth of LL2 tumor cells and induced apoptosis through the up and down-regulation of Bcl-2 gene family.