• Asian-Australasian Journal of Animal Sciences
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• 제22권1호
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• pp.20-25
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• 2009

Xenotransplantation of pig organs into humans is a potential solution for the shortage of donor organs for transplantation. However, multiple immune barriers preclude its clinical application. In particular, the initial type of rejection in xenotransplantation is an acute cellular rejection by host $CD8^+$ cytotoxic T lymphocyte (CTL) cells that react to donor major histocompatibility complex (MHC) class I. The human cytomegalovirus (HCMV) glycoprotein Unique Short (US) 2 specifically targets MHC class I heavy chains to relocate them from the endoplasmic reticulum (ER) membrane to the cytosol, where they are degraded by the proteasome. In this study we transfected the US2 gene into minipig fetal fibroblasts and established four US2 clonal cell lines. The integration of US2 into transgenic fetal cells was confirmed using PCR and Southern blot assay. The reduction of Swine Leukocyte Antigen (SLA)-I by US2 was also detected using Flow cytometry assay (FACS). The FACS analysis of the US2 clonal cell lines demonstrated a substantial reduction in SLA-I surface expression. The level (44% to 76%) of SLA-I expression in US2 clonal cell lines was decreased relative to the control. In cytotoxicity assay the rate of $CD8^+$ T cell-mediated cytotoxicity was significantly reduced to 23.8${\pm}$15.1% compared to the control (59.8${\pm}$8.4%, p<0.05). In conclusion, US2 can directly protect against $CD8^+$-mediated cell lysis. These results indicate that the expression of US2 in pig cells may provide a new approach to overcome the CTL-mediated immune rejection in xenotransplantation.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2001년도 제18차 정기총회 및 학술발표 PROCEEDINGS
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• pp.40-46
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• 2001

The use of pluripotent stem cells has tremendous advantages for various purposes but these cell lines with proven germ-line transmission have been completely established only in the mouse. Embryonic germ (EG) cell lines are also pluripotent and undifferentiated stem cells established from primordial germ cells (PGCs). This study was conducted to establish and characterize the chicken EG cells derived from gonadal primordial germ cells. We isolated gonadal PGCs from 5.5-day-old (stage 28) White leghorn (WL) embryos and established chicken EG cells lines with EG culture medium supplemented with human stem cell factor (hSCF), murine leukemia inhibitory factor (mLIF), bovine basic fibroblast growth factor (bFGF), human interleukin-11 (hIL-11), and human insulin-like growth factor-I (hIGF-I). These cells grew continuously for 4 months (10 passages) on a feeder layer of mitotically active chicken embryonic fibroblasts. These cells were characterized by screening with the Periodic acid-Shiff＇s reaction, anti-SSEA-1 antibody, and a proliferation assay after several passages. As the results, the chicken EG cells maintained characteristics of undifferentiated stem cells as well as that of gonadal PGCs. When cultured in suspension, the chicken EG cells successfully formed an embryoid body and differentiated into a variety of cell types when re-seeded onto culture dish. The chicken EG cells were injected into blastodermal layer at stage X and dorsal aorta of recipient embryo at stage 14 (incubation of 53hrs) and produced chimeric chickens with various differentiated tissues derived from the EG cells. The germline chimeras were also successfully induced by using EG cells. Thus, Chicken EG cells will be useful for the production of transgenic chickena and for studies of germ cell differentiation and genomic imprinting.

• 치과방사선
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• 제28권1호
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• pp.59-71
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• 1998

The radiation-induced apoptosis was studied for two human cancer cell lines (KB cells, RPMI 2650 cells) and the human gingival fibroblast cell line (HGF-1 cells). The single irradiation of 2, 10, 20Gy was done with 241.5 cGylmin dose rate using the /sup 137/Cs MK cell irradiator. The cells were stained with propidium iodide and examined under the fluoro-microscope and assayed with the flow cytometry a day after irradiation. Also, the LDH assay was done to determine the amount of necrotic cells. The obtained results were as follows: 1. On the fluoro-microscope, many fragmented nuclei were detected in the KB, RPMI 2650, and HGF-1 cells after irradiation. 2. On the DNA content histogram obtained from the flow cytometry, the percentages of the pre-Gl peak of the control and 2, 10 and 20Gy irradiation group were 4.5, 55.0, 52.3, and 66.6％ on KB cells, 2.7, 3.3, 31.8, and 32.6％ on RPMI 2650 cells and 2.8, 21.8, 30.4, and 40.2％ on HGF-1 cells respectively. 3. The number of Gl-stage cells was abruptly decreased after 2Gy irradiation on KB cells and 10Gy irradiation on RPMI 2650 cells, But there was a slight decrease without regard to irradiation dose on HGF-1 cells. 4. There was no significantly different absorbance in extracellular LDH assay along the experimental cell lines.

• 대한한의학방제학회지
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• 제22권2호
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• pp.35-43
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• 2014

Objectives : The purpose of this study was to identify antiproliferative effects of Salviae miltiorrhizae Radix(SM) extracts against cancer cell lines. Methods : We used 2 kinds of cancer cell lines such as colon cancer cells(HT-29), human oral epitheloid carcinoma cells(KB). MTT assay was performed to examine the efficacy of SM extracts on the cytostaticity of cancer cells in proportion to time and doses. Apoptosis was evaluated by DNA laddering and DAPI nuclei staining. Results : The MTT absorbances against HT-29 and KB of SM extracts were significantly decresed. DNA ladders could be identified in KB of SM extracts. The morphological change were observed and number of cells were decreased by SM extracts. Conclusions : SM extracts is considered to be effective to induce apoptosis and inhibit cancer cell proliferation.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.294.1-294
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• 1995

No Abstract, See Full Text

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.196.1-196.1
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• 2001

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.201.1-201.1
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• 2001

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2325-2331
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• 2013

Objective: To detect effects of plumbagin on proliferation and apoptosis in non-small cell lung cancer cell lines, and investigate the underlying mechanisms. Materials and Methods: Human non-small cell lung cancer cell lines A549, H292 and H460 were treated with various concentrations of plumbagin. Cell proliferation rates was determined using both cell counting kit-8 (CCK-8) and clonogenic assays. Apoptosis was detected by annexin V/propidium iodide double-labeled flow cytometry and TUNEL assay. The levels of reactive oxygen species (ROS) were detected by flow cytometry. Activity of NF-${\kappa}B$ was examined by electrophoretic mobility shift assay (EMSA) and luciferase reporter assay. Western blotting was used to assess the expression of both NF-${\kappa}B$ regulated apoptotic-related gene and activation of p65 and $I{\kappa}B{\kappa}$. Results: Plumbagin dose-dependently inhibited proliferation of the lung cancer cells. The IC50 values of plumbagin in A549, H292, and H460 cells were 10.3 ${\mu}mol/L$, 7.3 ${\mu}mol/L$, and 6.1 ${\mu}mol/L$ for 12 hours, respectively. The compound concentration-dependently induced apoptosis of the three cell lines. Treatment with plumbagin increased the intracellular level of ROS, and inhibited the activation of NK-${\kappa}B$. In addition to inhibition of NF-${\kappa}B$/p65 nuclear translocation, the compound also suppressed the degradation of $I{\kappa}B{\kappa}$. ROS scavenger NAC highly reversed the effect of plumbagin on apoptosis and inactivation of NK-${\kappa}B$ in H460 cell line. Treatment with plumbagin also increased the activity of caspase-9 and caspase-3, downregulated the expression of Bcl-2, upregulated the expression of Bax, Bak, and CytC. Conclusions: Plumbagin inhibits cell growth and induces apoptosis in human lung cancer cells through an NF-${\kappa}B$-regulated mitochondrial-mediated pathway, involving activation of ROS.

• 대한의생명과학회지
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• 제11권2호
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• pp.175-183
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• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권5호
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• pp.287-293
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• 2009

Cell survival is the result of a balance between programmed cell death and cellular proliferation. Cell membrane receptors and their associated signal transducing proteins control these processes. Of the numerous receptors and signaling proteins, epidermal growth factor receptor (EGFR) is one of the most important receptors involved in signaling pathways implicated in the proliferation and survival of cancer cells. EGFR is often highly expressed in human tumors including oral squamous cell carcinomas, and there is increasing evidence that high expression of EGFR is correlated with poor clinical outcome of common human cancers. Therefore, we examined the antiproliferative activity of gefitinib, epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), in head and neck cancer cell lines. SCC-9, KB cells were cultured and growth inhibition activity of gefitinib was measured with MTT assay. To study influence of gefitinib in cell cycle, we performed cell cycle analysis with flow cytometry. Western blot was done to elucidate the expression of EGFR in cell lines and phosphorylation of EGFR and downstream kinase protein, Erk and Akt. Significant growth inhibition was observed in SCC-9 cells in contrast with KB cells. Also, flow cytometric analysis showed G1 phase arrest only in SCC-9 cells. In Western blot analysis for investigation of EGFR expression and downstream molecule phosphorylation, gefitinib suppressed phosphorylation of EGFR and downstream protein kinase Erk, Akt in SCC-9. However, in EGFR positive KB cells, weak expression of active form of Erk and Akt and no inhibitory activity of phosphorylation in Erk and Akt was observed. The antiproliferative activity of gefitinib was not correlated with EGFR expression and some possibility of phosphorylation of Erk and Akt as a predictive factor of gefitinib response was emerged. Further investigations on more reliable predictive factor indicating gefitinib response are awaited to be useful gefitinib treatment in head and neck cancer patients.