• 동의생리병리학회지
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• 제26권4호
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• pp.519-526
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• 2012

Recently, herbal flavonoids have been implicated for anti-cancer therapy. Flavonoids as a commonly known for their anti-oxidant activity, are contained in the herbal medicine as well as root of plants, vegetables, fruits, grains, tea, and wine. Kaempferol, a component of Polygonati rhizoma, a member of the herbal flavonoids, has been studied for anti-hypercholesterol, anti-hypertension and anti-diabetes. It is also known to be effective in anti-cancer therapy for breast, prostate and other type of cancers. However, the anti-cancer therapeutic mechanisms are pooly understood. Here, we investigated the molecular mechanism underlying kaempferol-induced anti-cancer effects using the human liver cancer cell lines, Hep3B, HepG2, and Sk-Hep-1, and human Chang liver cell as a control. As shown by the FACS analysis, measurement of caspase activity, DAPI and trypan blue staining, and DNA fragmentation assay, kaempferol induced apoptosis in the liver cancer cells with the greater potential in Hep3B cells than other liver cancer cells. In addition, we performed microarray analysis to profile the genome-wide mRNA expression regulated by kaempferol. Many of the apoptosis-related genes were significantly induced in kaempferol-treated Hep3B cells, in particular, the genes associated with MAPK cascade. Additionally, kaempferol induced the mRNA expression of genes involved in MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathway, which are all known to trigger apoptosis. Overall, our data suggest that kaempferol has anti-liver cancer effects by inducing apoptosis through the MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathways.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.281.2-281.2
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• 2013

Since heavy metal ions included in water or food resources have critical effects on human health, highly sensitive, rapid and selective analysis for heavy metal detection has been extensively explored by means of electrochemical, optical and colorimetric methods. For example, quantum dots (QDs), such as semiconductor QDs, have received enormous attention due to extraordinary optical properties including high fluorescence intensity and its narrow emission peaks, and have been utilized for heavy metal ion detection. However, the semiconductor QDs have a drawback of serious toxicity derived from cadmium, lead and other lethal elements, thereby limiting its application in the environmental screening system. On the other hand, Graphene oxide (GO) has proven its superlative properties of biocompatibility, unique photoluminescence (PL), good quenching efficiency and facile surface modification. Recently, the size of GO was controlled to a few nanometers, enhancing its optical properties to be applied for biological or chemical sensors. Interestingly, the presence of various oxygenous functional groups of GO contributes to opening the band gap of graphene, resulting in a unique PL emission pattern, and the control of the sp2 domain in the sp3 matrix of GO can tune the PL intensity as well as the PL emission wavelength. Herein, we reported a photoluminescent GO array on which heavy metal ion-specific DNA aptamers were immobilized, and sensitive and multiplex heavy metal ion detection was performed utilizing fluorescence resonance energy transfer (FRET) between the photoluminescent monolayered GO and the captured metal ion.

• Mycobiology
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• 제50권5호
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• pp.366-373
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• 2022

Regulation of proper gene expression is important for cellular and organismal survival, maintenance, and growth. Abnormal gene expression, even for a single critical gene, can thwart cellular integrity and normal physiology to cause diseases, aging, and death. Therefore, gene expression profiling serves as a powerful tool to understand the pathology of diseases and to cure them. In this study, the difference in gene expression in Flammulina velutipes was compared between the wild type (WT) mushroom and the mutant one with clogging phenomenon. Differentially expressed transcripts were screened to identify the candidate genes responsible for the mutant phenotype using the DNA microarray analysis. A total of 88 genes including 60 upregulated and 28 downregulated genes were validated using the real-time quantitative PCR analysis. In addition, proteomic differences between the WT and mutant mushroom were analyzed using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF). Interestingly, the genes identified by these genomic and proteomic analyses were involved in stress response, translation, and energy/sugar metabolism, including HSP70, elongation factor 2, and pyruvate kinase. Together, our data suggest that the aberrant expression of these genes attributes to the mutant clogging phenotype. We propose that these genes can be targeted to foster normal growth in F. velutipes.

• Mycobiology
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• 제51권5호
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• pp.372-378
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• 2023

Lkh1, a LAMMER kinase homolog in the fission yeast Schizosaccharomyces pombe, acts as a negative regulator of filamentous growth and flocculation. It is also involved in the response to oxidative stress. The lkh1-deletion mutant displays slower cell growth, shorter cell size, and abnormal DNA content compared to the wild type. These phenotypes suggest that Lkh1 controls cell size and cell cycle progression. When we performed microarray analysis using the lkh1-deletion mutant, we found that only four of the up-regulated genes in the lkh1-deletion were associated with the cell cycle. Interestingly, all of these genes are regulated by the Mlu1 cell cycle box binding factor (MBF), which is a transcription complex responsible for regulating the expression of cell cycle genes during the G1/S phase. Transcription analyses of the MBF-dependent cell-cycle genes, including negative feedback regulators, confirmed the up-regulation of these genes by the deletion of lkh1. Pull-down assay confirmed the interaction between Lkh1 and Yox1, which is a negative feedback regulator of MBF. This result supports the involvement of LAMMER kinase in cell cycle regulation by modulating MBF activity. In vitro kinase assay and NetPhosK 2.0 analysis with the Yox1T40,41A mutant allele revealed that T40 and T41 residues are the phosphorylation sites mediated by Lkh1. These sites affect the G1/S cell cycle progression of fission yeast by modulating the activity of the MBF complex.

• Journal of Acupuncture Research
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• 제22권3호
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• pp.37-51
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• 2005

비만세포는 염증 및 알레르기 반응과 관련하여 우리 몸에서 주요한 작용을 하는 세포이다. 봉독은 현재까지 진통기전에 관련된 모델로 연구가 진행되어 왔으나, 최근에는 항염증이나 항알러지반응 둥에서 면역세포와 관련 한 연구가 진행 중에 있다. 본 연구는 봉독의 주요성분인 melittin과 MCD Peptide가 비만세포주에서의 유전자 발현에 미치는 영향을 연구함으로써 향후 유전자 언구에 관련한 기초를 제시하고자 하였다. 본 연구에서는 사람의 비만세포주를 이용하여, 세포독성 실험을 거쳐서 얻은 유효농도에서 각각 melittin과 MCD Peptide를 처치하고, 이때 변화하는 유전자의 발현양상을 microarray분석기법을 통하여 정보를 얻었다. 실험적 통계에 의하여 global M이 1 또는 -1 이상인 것을 유의한 것으로 보았을 때, melittin에서는 모두 7개 의 유전자가 항진되고, 8개의 유전자가 어제되었다. MCDP에서는 7개의 유전자가 항진되고 17개의 유전자가 억제되었다. 이들 유전자들이 주로 관련하는 체내의 작용은 세포내에서 단백결합, lymphocyte 기능의 활성화, macrophage 항원관련 및 세포핵의 수용체, GABA A receptor 관련물질, cAMP 반응요소와 연관된 단백질, 보체계 8번 및 B-cell 관련물질, 다낭성 신질환에 관련된 단백물질, 염증관련물질, 혈액응고에 영향을 주는 단백물질등과 연관이 되었다. 이러한 분석결과를 통하여 동복에서의 주요약리작용을 담당하는 melittin과 MCD peptide의 작용기전을 밝히는데 보다 유용한 자료를 얻을 수 있었으며, 향후에 봉독의 주요성분 및 전체봉 독액이 항알레르기반응이나 항염증작용에 미치는 영향에 대한 심도있는 연구가 필요할 것으로 사료된다.

• IMMUNE NETWORK
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• 제11권5호
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• pp.258-267
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• 2011

Background: Current management strategies attempt to diagnose rheumatoid arthritis (RA) at an early stage. Transcription profiling is applied in the search for biomarkers for detecting early-stage disease. Even though gene profiling has been reported using several animal models of RA, most studies were performed after the development of active arthritis, and conducted only on the peripheral blood and joint. Therefore, we investigated gene expression during the initial phase of collagen-induced arthritis (CIA) before the arthritic features developed in the thymus in addition to the peripheral blood and synovium. Methods: For gene expression analysis using cDNA microarray technology, samples of thymus, blood, and synovium were collected from CIA, rats immunized only with type II collagen (Cll), rats immunized only with adjuvant, and unimmunized rats on days 4 and 9 after the first immunization. Arrays were scanned with an Illumina bead array. Results: Of the 21,910 genes in the array, 1,243 genes were differentially expressed at least 2-fold change in various organs of CIA compared to controls. Among the 1,243 genes, 8 encode T-cell receptors (TCRs), including CD3${\zeta}$, CD3${\delta}$, CD3${\varepsilon}$, CD8${\alpha}$, and CD8${\beta}$ genes, which were down-regulated in CIA. The synovium was the organ in which the genes were differentially expressed between CIA and control group, and no difference were found in the thymus and blood. Further, we determined that the differential expression was affected by adjuvant more than Cll. The differential expression of genes as revealed by real-time RT-PCR, was in agreement with the microarray data. Conclusion: This study provides evidence that the genes encoding TCRs including CD3${\zeta}$, CD3${\delta}$, CD3${\varepsilon}$, CD8${\alpha}$, and CD8${\beta}$ genes were down-regulated during the initial phase of CIA in the synovium of CIA. In addition, adjuvant played a greater role in the down-regulation of the CD3 complex compared to CII. Therefore, the down-regulation of TCR gene expression occurred dominantly by adjuvant could be involved in the pathogenesis of the early stage at CIA.

• Molecular & Cellular Toxicology
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• 제4권4호
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• pp.318-322
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• 2008

Obesity is an increasing worldwide health problem that is strongly related to the imbalance of food intake and energy metabolism. It was well-known that several substances in the hypothalamus regulate food intake and energy metabolism. We planned an integrative study to elucidate the mechanism of the development of obesity. Firstly, to find candidate genes with the marvelous effect, the different expression in the hypothalamus between ob/ob and 48-h fasting mice was investigated by using DNA microarray technology. As a result, we found 3 genes [peroxisome proliferator activated receptor, gamma, coactivator 1 alpha (Ppargc1a), calmodulin 1 (Calm1), and complexin 2 (Cplx2)] showing the different hypothalamic expression between ob/ob and 48-h fasting mice. Secondly, a genetic approach on PPARGC1A gene was performed, because PPARGC1A acts as a transcriptional coactivator and a metabolic regulator. Two hundred forty three obese female patients with body mass index (BMI)${\geq}$25 and 285 control female subjects with BMI 18 to<23 were recruited according to the Classification of Korean Society for the Study of Obesity. Among the coding single nucleotide polymorphisms (cSNPs) of PPARGC1A, 2 missense SNPs (rs8192678, Gly482Ser; rs3736265, Thr612Met) and 1 synonymous SNP (rs3755863, Thr528Thr) were selected, and analyzed by PCR-RFLP and pyrosequencing. For the analysis of genetic data, chi-square ($X^2$) test and EH program were used. The rs8192678 was significantly associated with obese women (P<0.0006; odds ratio, 1.5327; 95% confidence interval, 1.2006-1.9568). Haplotypes also showed significant association with obese women ($X^2$=33.28, P<0.0008). These results suggest that PPARGC1A might be related to the development of obesity.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2006년도 Principles and Practice of Microarray for Biomedical Researchers
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• pp.83-89
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• 2006

Cellular functions are carried out by a concerted action of biochemical pathways whose components have genetic interactions. Abnormalities in the activity of the genes that constitute or modulate these pathways frequently have oncogenic implications. Therefore, identifying the upstream regulatory genes for major biochemical pathways and defining their roles in carcinogenesis can have important consequences in establishing an effective target-oriented antitumor strategy We have analyzed the gene expression profiles of human liver cancer samples using cDNA microarray chips enriched in liver and/or stomach-expressed cDNA elements, and identified groups of genes that can tell tumors from non-tumors or normal liver, or classify tumors according to clinical parameters such as tumor grade, age, and inflammation grade. We also set up a high-throughput cell-based assay system (cell chip) that can monitor the activity of major biochemical pathways through a reporter assay. Then, we applied the cell chip platform for the analysis of the HCC-associated genes discovered from transcriptome profiling, and found a number of cancer marker genes having a potential of modulating the activity of cancer-related biochemical pathways such as E2F, TCF, p53, Stat, Smad, AP-1, c-Myc, HIF and NF-kB. Some of these marker genes were previously blown to modulate these pathways, while most of the others not. Upon a fast-track phenotype analysis, a subset of the genes showed increased colony forming abilities in soft agar and altered cell morphology or adherence characteristics in the presence of purified matrix proteins. We are currently analyzing these selected marker genes in more detail for their effects on various biological Processes and for Possible clinical roles in liver cancer development.

• Molecules and Cells
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• 제37권10호
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• pp.734-741
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• 2014

Histone modifications on major transcription factor target genes are one of the major regulatory mechanisms controlling adipogenesis. Plant homeodomain finger 2 (PHF2) is a Jumonji domain-containing protein and is known to demethylate the histone H3K9, a repressive gene marker. To better understand the function of PHF2 in adipocyte differentiation, we constructed stable PHF2 knock-down cells by using the mouse pre-adipocyte cell line 3T3-L1. When induced with adipogenic media, PHF2 knock-down cells showed reduced lipid accumulation compared to control cells. Differential expression using a cDNA microarray revealed significant reduction of metabolic pathway genes in the PHF2 knock-down cell line after differentiation. The reduced expression of major transcription factors and adipokines was confirmed with reverse transcription- quantitative polymerase chain reaction and Western blotting. We further performed co-immunoprecipitation analysis of PHF2 with four major adipogenic transcription factors, and we found that CCATT/enhancer binding protein (C/EBP)${\alpha}$ and C/EBP${\delta}$ physically interact with PHF2. In addition, PHF2 binding to target gene promoters was confirmed with a chromatin immunoprecipitation experiment. Finally, histone H3K9 methylation markers on the PHF2-binding sequences were increased in PHF2 knock-down cells after differentiation. Together, these results demonstrate that PHF2 histone demethylase controls adipogenic gene expression during differentiation.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권4호
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• pp.319-324
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• 2006

Although the sera used in animal cell culture media provide the macromolecules, nutrients, hormones, and growth factors necessary to support cell growth, it could also be an obstacle to the production of recombinant proteins in animal cell culture systems used in many sectors of the biotechnology industry. For this reason, many research groups, including our laboratory, have been trying to develop serum-free media (SFM) or serum-supplemented media (SSM) for special or multi-purpose cell lines. The Chinese hamster ovary (CHO) cell, for example, is frequently used to produce proteins and is especially valuable in the large-scale production of pharmaceutically important proteins, yet information about its genome is lacking. Also, SFMs have only been evaluated by comparing growth patterns for cells grown in SFMs with those grown in SSM or by measuring the titer of the target protein obtained from cells grown in each type of medium. These are not reliable methods of obtaining the type of information needed to determine whether an SFM should be replaced with an SSM. We carried out a cDNA microarray analysis to evaluate MED-3, an SFM developed in our laboratory, as a CHO culture medium When CHO cells were cultured in MED-3 instead of an SSM, several genes associated with cell growth were down-regulated, although this change diminished over time. We found that the insulin-like growth factor (IGF) gene was representative of the proteins that were down-regulated in cells cultured in MED-3. When several key supplements - including insulin, transferrin, ethanolamine, and selenium - were removed from MED-3, the IGF expression was consistently down- regulated and cell growth decreased proportionately. Based on these results, we concluded that when an SFM is used as a culture medium, it is important to supplement it with substances that can help the cells maintain a high level of IGF expression. The data presented in this study, therefore, might provide useful information for the design and development of SFM or SSM, as well as for the design of genome-based studies of CHO cells to determine how they can be used optimally for protein production in pharmaceutical and biomedical research.