• Environmental Mutagens and Carcinogens
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• v.23 no.2
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• pp.45-50
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• 2003

Biological activities of PAHs are not known although PAHs are considered as carcinogens. Recent industrial society has human widely exposed to PAHs (polynuclear aromatic hydrocarbons) that are comming from the incomplete combustion of organic material as wider spread environmental contaminants. Our laboratory have been studied the effect of PAHs in the human breast cancer MCF-7 cells. In this study, we examined the human breast cancer MCF-7 cells as a new system to evaluate bioactivity of PAHs. We have selected 13 PAHs to examine bioassay using CYP1A1-luciferase reporter gene expression system where CYP1A1 1.6 Kb 5flanking region DNA was cloned in front of luciferase reporter gene and this plasmid was transfected into MCF-7 cells transiently. This cells then used for the study to observe the effect of PAHs. We demonstrated that PAHs induced the CYP1A1 promoter, CYP1A1 mRNA and 7-ethoxyresolufin O-deethylase (EROD) activities in a concentration-dependant manner. None of PAHs that we have tested showed stronger stimulatory effect on CYP1 gene expression than TCDD. Benz(a)anthracene and benzo(b)fluoranthene were weak responders to CYP1A1 promoter activity stimulation, CYP1A1 mRNA and EROD induction in MCF-7 cells and these chemicals seemed to respond less either CYP1A1 mRNA or EROD than CYP1A1 promoter activity. Benzo(k)fluoranthene, chrysene, and dibenzo(a, h)anthracene showed strong response to CYP1A1 promoter activity stimulation, CYP1A1 mRNA increase and also EROD induction in MCF-7 cells. Results of dose response study suggested that two strong responding PAHs, such as benzo(k)fluoranthene and dibenzo(a, h)anthracene might be mediated through Aryl hydrocarbon receptors system in MCF-7 cells.

• IMMUNE NETWORK
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• v.8 no.4
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• pp.137-142
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• 2008

Background: CD11c, also known as integrin alpha x, is one of the optimum markers of dendritic cells. However, the regulation of the CD11c expression in mouse has not been identified yet. In this study, in order to analyze the regulation of CD11c expression, the promoter of CD11c was cloned and characterized. Methods: To identify the promoter portion, various sizes of what are considered to be CD11c promoter fragments was amplified by polymerase chain reaction (PCR), using mouse genomic DNA as a template. After sequence was obtained, these fragments were transfected into various cell lines including mouse dendritic cell lines such as JAWSII and DC2.4 and L929 as control cell line.. The promoter activity of three promoter fragments was measured and compared by luciferase activity in the transfected cells. Results: Three clones with size of 1kb, 3kb and 6kb were obtained from mouse genomic DNA. Flow cytometry analysis of JAWSII cells revealed that 52% of the cells expressed CD11c, which was confirmed by RT-PCR analysis. On the contrary, L929 and DC 2.4 cells did not express CD11c. The CD11c+ JAWSII cells were enriched from 52% to 90% with cell sorter. The comparative luciferase activity analyisis demonstrated that the region responsible for tissue specific expression was contained within -3 kb and the clone with size of 3 kb particularly showed higher luciferase activity than 6 kb and 1 kb clones. Conclusion: The CD11c promoter region containing the region responsible for tissue specificity was successfully cloned and -3 kb region showed the highest activity.

• Molecular & Cellular Toxicology
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• v.4 no.1
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• pp.11-15
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• 2008

The expression of neuronal nitric oxide synthase (nNOS) is regulated by various spliced first exons (exon 1a-1i), sharing differentially common exon 2 in diverse human tissues. The highly complex structure and regulation of human nNOS gene gave limitations of information for the precise mechanism of nNOS regulation. In the present study, we report that the repeats of polymorphic dinucleotides $(GT)^nA(TG)^n$ repeats located in just upstream to the exon 1f in human nNOS gene play suppressive role in transcription, as shown in the characteristics of Z-DNA motif in other genes. In neuronal and trophoblast cells transfected transiently with luciferase construct without dinucleotide repeats at the 5'-flanking region of exon 1f in nNOS gene, the luciferase activity was increased markedly. However, the presence of the dinucleotide repeats dramatically suppressed the luciferase activity to the basal level, and which was dependent on the length of $(GT)^n$ and $(TG)^n$ repeats. More importantly, we found the polymorphisms in the length of dinucleotide repeats in human. Furthermore, we show for the first time here that there is a significant association of the lengths of polymorphic dinucleotide $(GT)^n$ and $(TG)^n$ repeats with the risk of schizophrenia.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.88-99
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• 2008

Objectives: In order to identify the anti-inflammatory and analgesic properties of Salvia miltiorrhiza (Dan-Sam), widely used in Korean traditional medicine, an in vitro screening system was designed using pGL3, a luciferase reporter vector, and the tumor necrosis factor (TNF)-${\alpha}$ and cyclooxygenase (COX)-2 as target genes. Methods: The promoter regions of each gene were generated by PCR using the human chromosome as template DNA, and inserted into pGL3 vector with Kpn I and Hind III. The final construct was transfected into human myelomonocytic leukemia cells (U-937) that could be differentiated and activated by phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). Using this system, the anti-inflammatory and analgesic effects of several herbal extracts regarded to have the medicinal effects of diminishing body heat and complementing Qi were tested. The chemicals PD98059 and berberine chloride were used as controls of the transcriptional inhibitors of TNF-${\alpha}$ and COX-2, respectively. Results: Salvia miltiorrhiza (Dan-Sam) demonstrated significant decrease of TNF-${\alpha}$ and COX-2 mRNA in the in vitro assay system. In MTT assay, Salvia miltiorrhiza (Dan-Sam) did not significantly inhibit the survival and proliferation of human myelomonocytic leukemia cells (U-937). Conclusions: Salvia miltiorrhiza (Dan-Sam) was found to exhibit the significant medicinal properties of anti-inflammatory and analgesic effects.

• Toxicological Research
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• v.20 no.3
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• pp.205-211
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• 2004

Concern that some chemicals in our environment may affect human health by disrupt-ing normal endocrine function has prompted a research on interactions of environmental contaminants with steroid hormone receptor. Toxaphene and chlordane are among the 12 persistent organic pollutants identified by the United Nations Environment Programme as requiring urgent attention. We compared the estrogenic activity of two organochlorine pesticides, toxaphene and chlordane, at estrogen receptor a (ER$\alpha$) and estrogen receptor $\beta$ (ER$\beta$). Human hepatoma cells (HepG2) were transiently transfected with rat ER$\alpha$ or ER$\beta$ plus an estrogen-responsive complement C3-luciferase (C3-Luc) reporter gene. After transfection, cells were treated with various concentrations of toxaphene and chlordane to investigate agonism or antagonism of these chemicals. Both toxaphene and chlordane were potent agonists in HepG2 cells for ER$\alpha$. In contrast, these chemicals had a minimal agonist activity with ER$\beta$ and almost abolished 17$\beta$-estradiol-induced ER$\beta$-mediated activity. Therefore, toxaphene and chlordane behaved as an ER$\alpha$ agonist and an ER$\beta$ antagonist with estrogen-responsive reporter plasmid C3-Luc, and exposure to these organochlorine pesticides could have a crictical effect on normal endocrine function.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.89-89
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• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1Al. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.531-538
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• 2017

This study was performed to investigate the effects of garlic on uncoupling protein 2 (UCP2) transcriptional regulation of UCP2-luciferase transgenic mice fed on a high fat diet to induce obesity. To examine the transcriptional regulation of UCP2, we generated transgenic mice with a UCP2 promoter (-1,830/+30 bp) containing luciferase as a reporter gene. UCP2-luciferase transgenic mice were fed a 45% high-fat diet for 8 weeks to induce obesity. Subsequently, mice were maintained on either a high-fat control diet (TG-CON), or high-fat diets supplemented with 2% (TG-GL2) or 5% (TG-GL5) garlic for a further 8 weeks. Dietary garlic reduced body weight and energy efficiency ratio in the TG-GL5 group, compared to the TG-CON group. Furthermore, garlic supplementation significantly decreased white adipose tissue fat mass and plasma levels of triglycerides, total cholesterol, and leptin in the TG-GL2 and TG-GL5 groups, compared to the TG-CON group. Specifically, UCP2 promoter activity in metabolic tissues such as liver, white adipose tissue, brown adipose tissue, and skeletal muscle was increased by garlic supplementation. These results suggest that dietary garlic was partially associated with an increase of UCP2 transcriptional activity in metabolic tissues for decreasing obesity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6557-6562
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• 2013

Objective: Specific promoters could improve efficiency and ensure the safety of gene therapy. The aim of our study was to screen examples for lung cancer. Methods: The firefly luciferase gene was used as a reporter, and promoters based on serum markers of lung cancer were cloned. The activity and specificity of seven promoters, comprising CEACAM5 (carcinoembryonic antigen, CEA), GRP (Gastrin-Releasing Peptide), KRT19 (cytokeratin 19, KRT), SFTPB (surfactant protein B, SP-B), SERPINB3 (Squamous Cell Carcinoma Antigen, SCCA), SELP (Selectin P, Granule Membrane Protein 140kDa, Antigen CD62, GMP) and DKK1 (Dickkopf-1) promoters were compared in lung cancer cells to obtain cancer-specific examples with strong activity. Results: The CEACAM5, DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB promoters were cloned. Furthermore, we successfully constructed recombinant vector pGL-CEACAM5 (DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB) contained the target gene. After cells were transfectedwith recombinant plasmids, we found that the order of promoter activity from high to low was SERPINB3, DKK1, SFTPB, KRT19, CEACAM5, SELP and GRP and the order for promoters regarding specificity and high potential were SERPINB3, DKK1, SELP, SFTPB, CEACAM5, KRT19 and GRP. Conclusion: The approach adopted is feasible to screen for new tumour specific promoters with biomarkers. In addition, the screened lung-specific promoters might have potential for use in lung cancer targeted gene therapy research.

• Biomedical Science Letters
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• v.13 no.3
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• pp.239-244
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• 2007

Hoxc8 is one of the homeotic developmental control genes regulating the expression of many downstream target genes, through which animal body pattern is established during embryonic development. In previous proteomics analysis, proliferating cell nuclear antigen (PCNA) which is also known as cyclin, has been implied to be regulated by Hoxc8 in F9 murine embryonic teratocarcinoma cell. When the 5' upstream region of PCNA was analyzed, it turned out to contain 20 Hox core binding sites (ATTA) in about 1.17 kbp (kilo base pairs) region ($-520{\sim}-1690$). In order to test whether this region is responsible for Hoxc8 regulation, the upstream 2.3 kbp fragment of PCNA was amplified through PCR and then cloned into the pGL3 basic vector containing a luciferase gene as a reporter. When the luciferase activity was measured in the presence of effector plasmid (pcDNA : c8) expressing murine Hoxc8, the PCNA promoter driven reporter activity was reduced. To confirm whether this reduction is due to the Hoxc8 protein, the siRNA against Hoxc8 (5'-GUA UCA GAC CUU GGA ACU A-3' and 5'-UAG UUC CAA GGU CUG AUA C-3') was prepared. Interestingly enough, siRNA treatment up regulated the luciferase activity which was down regulated by Hoxc8, indicating that Hoxc8 indeed regulates the expression of PCNA, in particular, down regulation in NIN3T3 cells. These results altogether indicate that Hoxc8 might orchestrate the pattern formation by regulating PCNA which is one of the important proteins involved in several processes such as DNA replication and methylation, chromatin remodeling, cell cycle regulation, differentiation, as well as programmed cell death.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.179-179
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• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1A1. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.