• Molecules and Cells
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• v.37 no.3
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• pp.264-269
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• 2014

The molecular interaction between tumor suppressor p53 and the anti-apoptotic Bcl-2 family proteins plays an essential role in the transcription-independent apoptotic pathway of p53. In this study, we investigated the binding of p53 DNA-binding domain (p53DBD) with the anti-apoptotic Bcl-2 family proteins, Bcl-w, Mcl-1, and Bcl-2, using GST pull-down assay and NMR spectroscopy. The GST pull-down assays and NMR experiments demonstrated the direct binding of the p53DBD with Bcl-w, Mcl-1, and Bcl-2. Further, NMR chemical shift perturbation data showed that Bcl-w and Mcl-1 bind to the positively charged DNA-binding surface of p53DBD. Noticeably, the refined structural models of the complexes between p53DBD and Bcl-w, Mcl-1, and Bcl-2 showed that the binding mode of p53DBD is highly conserved among the anti-apoptotic Bcl-2 family proteins. Furthermore, the chemical shift perturbations on Bcl-w, Mcl-1, and Bcl-2 induced by p53DBD binding occurred not only at the p53DBD-binding acidic region but also at the BH3 peptide-binding pocket, which suggests an allosteric conformational change similar to that observed in Bcl-$X_L$. Taken altogether, our results revealed a structural basis for a conserved binding mechanism between p53DBD and the anti-apoptotic Bcl-2 family proteins, which shed light on to the molecular understanding of the transcription-independent apoptosis pathway of p53.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.72-74
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• 2004

In this study, we used a inductively coupled plasma (ICP) source for etching $Al_2O_3$ thin films because of its high plasma density, low process pressure and easy control bias power. $Al_2O_3$ thin films were etched using $Cl_2/BCl_3$, $N_2/Cl_2/BCl_3$, and Ar/$Cl_2/BCl_3$ plasma. The experiments were carried out measuring the etch rates and the selectivities of $Al_2O_3$ to $SiO_2$ as a function of gas mixing ratio, rf power, and chamber pressure. When $Cl_2$ 50% was added to $Cl_2/BCl_3$ plasma, the etch rate of the $Al_2O_3$ films was 118 nm/min. We also investigated the effect of gas addition. In case of $N_2$ addition, the etch rate of the $Al_2O_3$ films decreased while $N_2$ was added into $Cl_2/BCl_3$ plasma. However, the etch rate increased slightly as Ar added into $Cl_2/BCl_3$ plasma, and then further increase of Ar decreased the etch rate. The maximum etch rate was 130 nm/min at Ar 20% in $Cl_2/BCl_3$ plasma, and the highest etch selectivity was 0.81 in $N_2$ 20% in $Cl_2/BCl_3$ plasma. And, we obtained the results that the etch rate increases as rf power increases and chamber pressure decreases. The characteristics of the plasmas were estimated using optical emission spectroscopy (OES).

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.962-974
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• 1998

Background: Alteration of p53 tumor suppressor genes is most frequently identified in human neoplasms, including lung carcinoma. It is well known that bcl-2 oncoprotein protects cells from apoptosis. Recent studies have demonstrated that bcl-2 expression is associated with favorable prognosis for patients with non-small cell lung carcinoma. However, the precise biologic role of bcl-2 in the development of these tumors is still obscure. p53 and bcl-2 have important regulatory influence in the apoptotic pathway and thus their relationship is of interest in tumorigenesis, especially lung cancer. Purpose: The author investigated to know the prognostic significance of the expression of p53 and bcl-2 in radically resected non-small cell lung cancer. Method: 84 cases of formalin-fixed paraffin-embedded blocks from resected primary non-small cell lung cancer from 1980 to 1994 at Hanyang University Hospital were available for both clinical follow-up and immunohistochemical staining using monoclonal antibodies for p53 and bcl-2. Results : The histologic classification of the tumor was based on WHO criteria., and the specimens included 45 squamous cell carcinomas(53.6%), 28 adeonocarcinomas(33.3%) and 11 large cell carcinomas(13.1 %). p53 immunoreactivity was noted in 47 cases of 84 cases(56.0%). bcl-2 immunoreactivity was noted in 15 cases of 84 cases(17.9%). The mean survival duration was $64.23{\pm}10.73$ months in bcl-2 positive group and $35.28{\pm}4$. 39 months in bcl-2 negative group. The bcl-2 expression was significantly correlated with survival in radically resected non-small cell lung cancer patients(p=0.03). The mean survival duration was $34.71{\pm}6.12$ months in p53 positive group and $45.35{\pm}6.30$ months in p53 negative group(p=0.21). The p53 expression was not predictive for survival. There was no correlation between combination of the different status of p53 and bcl-2 expression in our study. Conclusions : The interaction and the regulation of new biologic markers, such as those involved in the apoptotic pathway, are complex. bcl-2 overexpression is a good prognostic factor in non-small cell lung cancer and p53 expression is not significantly associated with the prognostic factor in non-small cell lung cancer.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1200-1205
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• 1998

Background: Lung cancer formation is a multistage process involving activation of protooncogene and inactivation of tumor suppressor genes. We evaluate the significance of cyclin D1, p53, bcl-2 gene mutations in patients with curatively resected stage IIIA non-small cell lung cancer(NSCLC). Material and Method: One hundred consecutive cases of stage IIIA lung cancers from patients operated on curatvely between 1990 and 1995 for which adequate paraffin blocks and clinical history were available. Immunohistochemical studies were performed on the representative tissue sections from each case by the labelled streptovidin- biotin method. Sections for cyclin D1, p53, Bcl-2 immunostaining were pretreated in a microwave oven for 10 to 20 minutes in citrate buffer before immunostaining. The overnight incubation with NCL-cyclin D1-GM for cyclin D1, with clone DO-7 for p53, with clone 124 for bcl-2 was done. Mean follow-up was 24.1 months (range 2-84 months) after operation. Result: One hundred cases of lung cancers were composed of 56 cases of squamous cell carcinoma, 37 cases of adenocarcinoma, 5 cases of adenosquamous cell carcinoma, and 2 cases of large cell carcinoma. The 5-year survival was 32.1%. The positive expression rate of cyclin D1 was 35%, p53 was 56%, and bcl-2 was 17%. But there were no correlation between cyclin D1, p53, Bcl-2 protein expression and survival. Conclusion: These observation indicate that cyclin D1, p53, bcl-2 protein overexpression might be implicated in the oncogenesis of non-small cell lung carcinomas but they have no usefulness as a prognostic marker.

• Herbal Formula Science
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• v.31 no.4
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• pp.253-264
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• 2023

Objectives : Bambusae Caulis in Liquamen (BCL), a traditional herbal medicine, is a distilled product of condensation from the burning of fresh bamboo stems. We previously identified the anti-oxidant capacity of BCL in hepatocytes and suggested that BCL is a promising therapeutic candidate for treating oxidative stress-induced hepatocellular damage. Despite the importance of the role played by Kupffer cells in liver disease, the efficacy of BCL on Kupffer cells is unclear. Therefore, this study aimed to determine whether BCL could suppress LPS-induced inflammation and LPS+ATP-induced inflammasomes in Kupffer cells. Methods : We used ImKCs, a murine immortalized Kupffer cell line to examined whether BCL inhibited LPS-induced inflammation response and oxidave stress. And, we prepared a total of 18 L of BCL, purchased from Bamboo Forest Foods Co., Ltd. (648 Samdari, Damyang-eup, Damyang-gun, Jeollanam-do, Republic of Korea), was concentrated using a decompression concentrator. Result : The LPS-induced release of inflammatory cytokines was abolished by BCL treatment. Also, BCL treatment suppressed the LPS+ATP-induced expression of inflammasome proteins (NLRP3, IL-1, and IL-18), and inhib β ited the release of IL-1 . BCL decreased LPS-or LPS+ATP-induc β ed reactive oxygen species production. In addition, BCL increased nuclear translocation of Nrf2 and the expression of HO-1 in a time-dependent manner. Conclusion : These results suggest the efficacy of BCL with respect to its anti-inflammatory and anti-inflammasome effects mediated by Nrf2 in Kupffer cells.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.564-570
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• 2005

In the present study, the protective effects of Bcl-2 over-expression in a suspension culture (without any adaptation) and spent medium (low nutrient and high toxic metabolite conditions) were investigated. In the suspension culture without prior adaptation, the viability of the control cell line fall to 0% by day 7, whereas the Bcl-2 cell line had a viability of 65%. The difference in the viability and viable cell density between the Bcl-2 and control cell lines was more apparent in the suspension culture than the static culture, and became even more apparent on day 6. Fluorescence microscopic counting revealed that the major mechanism of cell death in the control cell line in both the static and suspension cultures was apoptosis. For the Bcl-2 cell lines, necrosis was the major mode of cell death in the static culture, but apoptosis became equally important in the suspension culture. When the NS0 6A1 cell line was cultured in spent medium taken from a 14 day batch culture, the control cell line almost completely lost its viability by day 5, whereas, the Bcl-2 still had a viability of 73%. The viable cell density and viability of the Bcl-2 cell line cultivated in fresh medium were 2.2 and 2.7 fold higher, respectively, than those of the control cultures. However, the viable cell density and viability of the Bcl-2 cultivated in the spent medium were 8.7 and 7.8 fold higher, respectively, than those of the control cultures. Most of the dead cells in the control cell line were apoptotic; whereas, the major cell death mechanisms in the Bcl-2 cell line were necrotic.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6289-6292
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• 2015

Purpose: To determine the biological behaviour of common odontogenic cystic lesions by analysing and comparing bcl-2 expression amongst them. Materials and Methods: Our study covered 90 formalin fixed paraffin embedded tissue samples: 26 primary cases each of radicular cysts (RC), dentigerous cysts (DC) and odontogenic keratocysts (OKC) and 12 of recurrent OKCs. Bcl-2 expression was analysed immunohistochemically and data analysis was accomplished using SPSS version 17.0. Means were taken for age while for gender and site of the lesions frequencies and percentages were determined. The Chi-square test was applied to evaluate any statistically significant difference of bcl-2 expression in these lesions and p value of ${\leq}0.05$ was taken as significant. Results: All the recurrent OKCs showed a strong positivity for bcl-2 that was absent in all of its primary cases (p value<0.05). Although variation in expression of bcl-2 was not found to be statistically significant between RC and DC, however, it became significant when all primary cases of these common odontogenic lesions were compared. Conclusions: Recurrent OKC showed comparatively a more aggressive behaviour than their primary counterparts and also from RC and DC. Bcl-2 proved to be a valuable adjunct in determining aggressive biological behaviour of odontogenic lesions.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1250-1259
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• 2007

Bambusae Caulis in Liquamen(BCL) has been commonly prescribed for stroke patients in the traditional Oriental medicine. So this study is aims to investigate the anti-apoptotic and neuroprotective effects of Bambusae Caulis in Liquamen(BCL) manufactured by different production process on the focal ischemia induced by intraluminal filament insertion in rats. The focal ischemia was induced by intraluminal filament insertion into middle cerebral artery. The animals were divided into four groups (n=15 in each group). The ischemia induced and not treated group : Control group, the ischemia induced and oral medication of the three kinds of BCL : BCL-A group, BCL-B group, BCL-C group. BCL-A was produced by heating at a low temperature$(250^{\circ} C)$ in electric kiln and filtering. BCL-B was produced by heating at a high temperature$(900^{\circ} C{\sim}1,000^{\circ}C)$ in yellow earth kiln and refining and filtering. BCL-C was produced by heating at a low temperature$(400^{\circ} C)$ yellow earth kiln and no refining and filtering. The anti-apoptotic and neuroprotective effects of the oral medication of BCL were observed by Bax, BCL-2, cytochrome c, mGluR5, cresyl violet and ChAT-stain. Our study suggests that BCl-A(was produced by heating at a low temperature in electric kiln and filtering) and BCL-C(was produced by heating at a low temperature in yellow earth kiln and no refining and filtering) show anti-apoptotic and neuroprotective effects on the focal ischemia induced by intraluminal filament insertion in rats and BCL-C is more effective than BCL-A.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.144-149
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• 2008

Despite versatile activity (cancericidal, antimicrobial, hypoxia inducible factor (HIF) inhibition, immune deactivation of DNA bis-intercalation agent, echinomycin, its specific mechanism has been elusive. Of these novel mechanisms, we reported that using human colon cancer cells (HT-29), apoptotic machinery induced by echinomycin might be dependent of caspase-3 pathway. Despite a partial enlightenment of prototypic signal path triggered by echinomycin, the role of Bcl-2 in this signaling pathway is unclear. To address this issue, we explored whether or not echinomycin would overcome the anti-apoptotic impact of Bcl-2 in HT-29 cells by the controlled Bcl-2 overexpression. Prior to this proof, we confirmed that echinomycin induces mitochondrial depolarization, then triggering the mitochondrial pathway of apoptosis with an involvement of upstream cas-pases-3. Transiently transfection with inactive Bax-DNA failed to prevent echinomycin-induced apoptosis in HT-29 cells. To dissect the role of Bcl-2 in echinomycin-induced apoptosis, HT-29 cells were transiently transfected with Bcl-2 DNA for overexpression and then treated with echinomycin for 24h. Combined analyses of DNA fragmentation and flow cytometric analysis clearly verified that echinomycin-induced apoptosis was drastically attenuated by Bcl-2 overexpression, whereas a control vector rarely affected echinomycin-induced apoptosis. Collectively, these data verify that Bcl-2 regulates echinomycin-induced apoptosis in HT-29 cells. To my knowledge, this is the first evidence that of diverse, structured minor groove binders (MGB), the prototypic echinomycin might control the apoptotic signaling via Bcl-2-mitochondrial pathway.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.3
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• pp.161-168
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• 2011

Purpose: The odontogenic keratocysts demonstrated a high recurrence rate and a biologically aggressive nature. This might be due to unknown factors inherent in the epithelium or enzymatic activity in the fibrous wall. Bcl-2 protein is characterized by its ability to inhibit apoptosis. The aim of this study was to evaluate the expression and distribution of bcl-2 in the OKCs, its possible relationship with the tumorous characteristics, such as the aggressive nature and high recurrence rate, and its usefulness to differentiate OKCs from dentigerous cysts. Materials and Methods: Formalin fixed paraffin-embedded tissue sections of 53 OKCs, and 44 dentigerous cyst were immunohistochemically analyzed quantitatively for the immunoreactivity of the bcl-2 protein with i-solution. Results: More Bcl-2 expression was observed in the OKCs (mean34.387%) than dentigerous cyst (mean11.144%) with statistical significance (P<0.001). Seventeen and 15 of the 32 OKCs in this study showed positivity in the basal layer and basal/suprabasal layers, respectively. In dentigerous cyst, 2 of 3 showed positivity in the basal cell layer. Conclusion: Considering that bcl-2 over expression may lead to the increased survival of epithelial cells, this study demonstrated a possible relationship between the aggressive nature of OKC and the intrinsic growth potential of its lining epithelium. Furthermore, the basal/suprabasal distribution of bcl-2 positive cells was observed in some OKCs, which might have a significant impact on the behavior of cysts. The bcl-2 expression of OKCs can be useful for differentiating OKCs from dentigerous cysts.