Biomedical subjects

Yong-Wan Kim

Publications and source records attributed to Yong-Wan Kim.

11 recordsLinked to original sources

PubMed2005

Array comparative genomic hybridization analysis of uterine leiomyosarcoma.

PURPOSE: Using a genome-wide array-based comparative genomic hybridization (array-CGH), DNA copy number changes in uterine leiomyosarcoma were analyzed. MATERIALS AND METHODS: We analyzed 4 cases of uterine leiomyoma and 7 cases of uterine leiomyosarcoma. The paraffin-fixed tissue samples were microdissected under microscope and DNA was extracted. Array-based CGH and fluorescence in situ hybridization (FISH) were carried out with Genome database (Gene Ontology). RESULTS: Uterine leiomyoma showed no genetic alterations, while all of 7 cases of uterine leiomyosarcoma showed specific gains and losses. The percentage of average gains and losses were 4.86% and 15.1%, respectively. The regions of high level of gain were 7q36.3, 7q33-q35, 12q13-12q15, and 12q23.3. And the regions of homozygous loss were 1p21.1, 2p22.2, 6p11.2, 9p21.1, 9p21.3, 9p22.1, 14q32.33, and 14q32.33 qter. There were no recurrent regions of gain, but recurrent regions of loss were 1p21.1-p21.2, 1p22.3-p31.1, 9p21.2-p22.2, 10q25-q25.2, 11q24.2-q25, 13q12-q12.13, 14q31.1-q31.3, 14q32.32-q32.33, 15q11-q12, 15q13-q14, 18q12.1-q12.2, 18q22.1-q22.3, 20p12.1, and 21q22.12-q22.13. In the high level of gain regions, BAC clones encoded HMGIC, SAS, MDM2, TIM1 genes. Frequently gained BAC clone-encoded genes were TIM1, PDGFR-beta, REC Q4, VAV2, FGF4, KLK2, PNUTL1, GDNF, FLG, EXT1, WISP1, HER-2, and SOX18. The genes encoded by frequently lost BAC clones were LEU1, ERCC5, THBS1, DCC, MBD2, SCCA1, FVT1, CYB5, and ETS2/E2. A subset of cellular processes from each gene was clustered by Gene Ontology database. CONCLUSION: Using array-CGH, chromosomal aberrations related to uterine leiomyosarcoma were identified. The high resolution of array-CGH combined with human genome database would give a chance to find out possible target genes present in the gained or lost clones.

Adult↗

PubMed2005

Protein array consisting of sol-gel bioactive platform for detection of E. coli O157:H7.

Sol-gel-derived bioactive platform was fabricated for detection of pathogenic microbes, E. coli O157:H7. Design flexibility of sol-gel technique and ease of fabrication can fulfill to create the surfaces with structural and chemical features that are compatible with biomaterials such as antibody, enzymes, etc. In this study, the bioactive platform was prepared based on the silica gels, which were produced by hydrolyzing tetraethylorthosilane (TEOS) in ethanol. The mercaptopropyl triethoxysilane (MPTS) was mixed with the TEOS solution for the surface functionalization of bioactive platform. During TEOS hydrolysis, the modified thin film was prepared by sol-gel dip coating. Antibody against E. coli O157:H7 was immobilized with a configuration of protein array using piezo-type dispensing system. Surface morphology of the prepared bioactive platform was analyzed using atomic force microscopy (AFM). The antibody-antigen interaction was investigated with fluorescence microscopy and sandwich type immunoassay using fluorescein isothiocyanate (FITC)-labeled antibody. The results showed that antibody was sequestered within the sol-gel-derived bio-gel due to physical adsorption. The measurement of E. coli O157:H7 was done using the fabricated antibody surface. The fluorescence intensity was proportional to the concentration of E. coli O157:H7, of which the detection limit was 10(2)CFU/ml.

Antibodies, Monoclonal↗

PubMed2005

Adenoviral p53 effects and cell-specific E7 protein-protein interactions of human cervical cancer cells.

We investigated the time-course tumor growth suppression effects of recombinant adenovirus expressing p53 on human cervical cancer cells and cell-specific E7 protein-protein interactions in cell lysates using surface plasmon resonance (SPR) biosensor. Six HPV-infected human cervical cancer cell lines (HPV 16-positive cells, CaSki and SiHa cells; HPV 18-positive cells, HeLa and HeLaS3 cells; and HPV negative C33A and HT3 cells) were used. After infection with AdCMVp53, the cell-specific growth inhibition was studied in vitro and in vivo. Also, we produced the recombinant E7 oncoprotein of HPV 16 type and tested chip-based protein-protein interactions with each cell lysate. For each cervical cancer cell, differential cell growth inhibitions were shown via cell count assay and MTT assay. Note that the same trend in suppression levels was shown in CaSki, HeLa and in SiHa, HeLaS3, respectively. In contrast, infection with AdCMVLacZ showed increased cell growth in a manner similar to the negative control group. The levels of p53 protein were notably expressed in CaSki and HeLa more than in SiHa and HeLaS3 for 4 days. In contrast, p53 expression was continually maintained in C33A and HT3 for 6 days. After transfection AdCMVp53 into CaSki- and SiHa-xenografted nude mice, the size of tumor was remarkably decreased in SiHa cells as compared to AdCMVLacZ transfection. The SPR sensor surface was successfully modified with the recombinant E7 oncoprotein and showed cell-specific interactions between E7 and its target proteins from cell lysates. The anti-tumor effects were accomplished via differential role of p53-specific apoptotic cell death, which is dependent upon the cervical cancer cell line. Also, a molecular level understanding of cell-dependent protein interaction effects of recombinant E7 was shown.

Adenoviridae↗

PubMed2005

In situ fabrication of self-transformable and hydrophilic poly(ethylene glycol) derivative-modified polysulfone membranes.

A self-transformable sulfonated poly(ethylene glycol) acrylate diblock copolymer (PEG-SO3A/OA) entrapped into polysulfone membrane was studied. The asymmetric membrane structure was prepared by a phase inversion process. The induced hydrophilicity by reorientation of diblock copolymer at the interface was evaluated by contact angle measurement, platelet adhesion test, and electron spectroscopy for chemical analysis (ESCA) depth profiling with ion sputtering. Molecular dynamic (MD) simulations as a function of copolymer density were also performed to obtain optimum interfacial structure information. The dependency of water clustering behavior as a hydrophilicity parameter was described in terms of an atom-atom radial distribution function (RDF). The results showed that the sulfonated diblock copolymer enhanced the hydrophilicity and long-term stability more than the copolymer having no hydrophobic block. Also, according to the ESCA, oxygen composition significantly began to decrease along the membrane depth, indicating the reorientation of diblock chains. The copolymer-entrapped surfaces significantly induced the degree of water clustering, and the resulting equilibrium rearrangement of interfacial structure was distinctly dependent upon the density of the copolymer.

Biocompatible Materials↗

PubMed2005

New approaches to pathogenic gene function discovery with human squamous cell cervical carcinoma by gene ontology.

PURPOSE: This study utilized mRNA differential display and the Gene Ontology (GO) analysis to characterize the multiple interactions of a number of genes with gene expression profile involved in squamous cell cervical carcinoma. METHODS: mRNA differential displays were used to identify potential transcripts that were differentially expressed between cervix cancers of 13 patients (invasive cancer stages Ib-IIb) and universal reference RNAs comprised of 17 different normal cervixes. Aberrant bands were excised and used to make cDNA, which was sequenced. DNA sequences were compared to other nucleic acids in the NCBR database for homology. Transcript expression was verified in select samples using RT-PCR and North blotting. The specific functions were correlated with gene expression patterns via gene ontology. RESULTS: Fifty-eight genes were up- or down-regulated above 2-fold and organized into reciprocally dependent sub-function sets depending on the cervical cancer pathway. The GO analysis showed that squamous cell cervical carcinogenesis underwent complete up-regulation of cell cycle, transport, epidermal differentiation, protein biosynthesis, and RNA metabolism. Also, genes belonging to protein metabolism and catabolism activity were significantly up-regulated. In contrast, significant down-regulation was shown in muscle development, cell adhesion, and damaged DNA binding activity. CONCLUSION: The GO analysis can overcome the complexity of the gene expression profile of the squamous cell cervical carcinoma-associated pathway and identify several cancer-specific cellular processes as well as genes of unknown function. Also, GO analysis can serve as a powerful basis for a molecular classification of carcinogenesis.

Apoptosis↗

PubMed2004

Recombinant adenovirus-p53 gene transfer and cell-specific growth suppression of human cervical cancer cells in vitro and in vivo.

PURPOSE: We investigated the time-course expression patterns of p53 and E6 on cervical cancer cells to obtain a molecular level understanding of cell-dependent tumor growth suppression effects of recombinant adenovirus expressing p53 in vitro and in vivo. METHODS: Four human papillomavirus (HPV)-infected human cervical cancer cell lines (HPV 16-positive cells, CaSki and SiHa cells; and HPV 18-positive cells, HeLa and HeLaS3 cells) were used. Also, HPV negative C33A and HT3 cell line that has a mutation on p53 gene were used. After infection with AdCMVp53, the cell growth inhibition was studied via cell count assay, MTT assay, and Neutral red assay. After transfecting AdCMVp53 and AdCMVLacZ into the cancer cells-xenografted nude mice, antitumor effects were investigated for 1 month, respectively. RESULTS: For each cervical cancer cell, IC50 was as follows; CaSki (68.5 multiplicity of infection, or MOI), SiHa (43.5 MOI), HeLa (31 MOI), HeLaS3 (42 MOI), C33A (21 MOI), and HT3 (62 MOI). In particular, complete inhibition of cell growth was observed at 125 MOI in both CaSki and SiHa cells. However, the complete inhibition was detected at 62.5 MOI in HeLa and HeLaS3. In contrast, at these MOI, no suppression of cell growth was observed when cells were infected with recombinant adenovirus expressing beta-gal as a negative control. The levels of p53 protein were notably expressed in CaSki and HeLa more than in SiHa and HeLaS3 on days 2 and 4. However, the p53 was only detected in HeLaS3 on day 6. In contrast, p53 expression was continually maintained in C33A and HT3 during the same periods. After transfection AdCMVp53 into CaSki- and SiHa-xenografted nude mice, the size of tumor was remarkably decreased in SiHa cells as compared to AdCMVLacZ transfection. CONCLUSION: The adenovirus-mediated p53 gene transfection was done effectively in vitro and in vivo. Also, the antitumor effects were accomplished via differential role of p53-specific apoptotic cell death, which is dependent upon the cervical cancer cell line.

Adenoviruses, Human↗

PubMed2004

Searching for pathogenic gene functions to cervical cancer.

OBJECTIVES: Molecular pathology of cervical cancers associated with human papillomavirus (HPV) infection is presently unclear. In an effort to clarify this issue, we investigated gene expression profiles and pathogenic cellular processes of cervical cancer lesions. METHODS: Tissues of 11 patients (invasive cancer stages Ib-IIIa) were investigated by a cDNA microarray of 4700 genes, hierarchical clustering and the Gene Ontology (GO). RESULTS: We identified 74 genes showing a more than 2-fold difference in their expression in at least 8 out of 11 patients. Among these, 33 genes were up-regulated, in contrast, 41 genes were down-regulated. The gene expression profiles were classified into mutually dependent 345 function sets, resulting in 611 cellular processes according to the GO. The GO analysis showed that cervical carcinogenesis underwent complete down-regulation of cell death, protein biosynthesis, and nucleic acid metabolism. Also, genes belonging to nucleic acid binding and structural molecule activity were significantly down-regulated. In contrast, significant up-regulation was shown in skeletal development, immune response, and extracellular activity. CONCLUSIONS: These data suggest that the regulated genes and cellular processes could be further used for predicting prognosis and diagnosis of cervical cancer patients, and further investigation and functional characterization of the identified genes is warranted.

Down-Regulation↗

PubMed2004

Anticancer effects of (-)-epigallocatechin-3-gallate on ovarian carcinoma cell lines.

PURPOSE: A constituent of green tea, (-)-epigallocatechin-3-gallate (EGCG), has been known to possess anti-cancer properties. In this study, we investigated the time-course anticancer effects of EGCG on human ovarian cancer cells to provide insights into the molecular-level understanding of growth suppression mechanism involved in EGCG-mediated apoptosis and cell cycle arrest. METHODS: Three human ovarian cancer cell lines (p53 negative, SKOV-3 cells; mutant type p53, OVCAR-3 cells; and wild type p53, PA-1 cells) were used. The effect of EGCG treatment was studied via cell count assay, cell cycle analysis, FACS, Western blot, and macroarray assay. RESULTS: EGCG exerts a significant role in suppressing ovarian cancer cell growth. Also, EGCG showed growth inhibitory effects in each cell line in a dose-dependent fashion and induced apoptosis and cell cycle arrest. The cell cycle was arrested at the G(1) phase by EGCG in SKOV-3 and OVCAR-3 cells. In contrast, the cell cycle was arrested in the G(1)/S phase arrest in PA-1 cells. EGCG differentially regulated the expression of genes and proteins (Bax, p21, Retinoblastoma, cyclin D1, CDK4, Bcl-X(L)) more than 2-fold, showing a possible gene regulatory role of EGCG. The continual expression in p21WAF1 suggests that EGCG acts in the same way with p53 proteins to facilitate apoptosis after EGCG treatment. And Bax, PCNA, and Bcl-X are important in EGCG-mediated apoptosis. In contrast, CDK4 and Rb are not important in ovarian cancer cell growth inhibition. CONCLUSION: EGCG can inhibit ovarian cancer cell growth through induction of apoptosis and cell cycle arrest as well as regulation of cell cycle-related proteins. Thereby, the EGCG-mediated apoptosis can be applied to an advanced strategy in the development of a potential drug against ovarian cancer.

Antineoplastic Agents, Phytogenic↗

PubMed2004

Comparison of effects of As2O3 and As4O6 on cell growth inhibition and gene expression profiles by cDNA microarray analysis in SiHa cells.

An arsenical compound, As2O3 has been reported to be effective for treating acute leukemia and induce apoptosis in many different tumor cell types. In this study we designed a novel arsenical compound, As4O6, and compared its ability to induce cell growth inhibition as well as gene expression profiles along with As2O3 in HPV16 infected SiHa cervical cancer cells. Both As2O3 and As4O6 induced apoptosis in SiHa cells, as determined by a DNA ladder formation. As4O6 was more effective in suppressing the growth of SiHa cells in vitro, as compared to As2O3. To further compare gene expression profiles between these two drugs, we used a 384 cDNA microarray system. The gene expression profiles were also classified into the Gene Ontology (GO) to investigate apoptosis-related cellular processes. In the case of As2O3, 41 genes were up- or down-regulated at least 2-fold, as compared to non-treatment, whereas, 65 genes were up- or down-regulated by As4O6 treatment. In particular, 27 genes were commonly regulated by both arsenic compounds. The GO analysis also indicated that down-regulation of cell-regulatory functions, such as cell cycle, protein kinase activity and DNA repair, induces an anti-tumor effect. Taken together, these data support that As4O6 could be more effective than As2O3 in inhibiting the growth of HPV16 infected cervical cancer cells. This appears to be mediated through a unique but overlapping regulatory mechanism(s), suggesting that the regulated genes and cellular processes could be used for a new potential drug approach for treating cervical cancer in clinical settings.

Antineoplastic Agents↗

PubMed2003

Targeted cellular process profiling approach for uterine leiomyoma using cDNA microarray, proteomics and gene ontology analysis.

This study utilized both cDNA microarray and two-dimensional protein gel electrophoresis technology to investigate the multiple interactions of genes and proteins involved in uterine leiomyoma pathophysiology. Also, the gene ontology analysis was used to systematically characterize the global expression profiles at cellular process levels. We profiled differentially expressed transcriptome and proteome in six-paired leiomyoma and normal myometrium. Screening up to 17 000 genes identified 21 upregulated and 50 downregulated genes. The gene-expression profiles were classified into mutually dependent 420 functional sets, resulting in 611 cellular processes according to the gene ontology. Also, protein analysis using two-dimensional gel electrophoresis identified 33 proteins (17 upregulated and 16 downregulated) of more than 500 total spots, which was classified into 302 cellular processes. Of these functional profilings, downregulations of transcriptomes and proteoms were shown in cell adhesion, cell motility, organogenesis, enzyme regulator, structural molecule activity and response to external stimulus functional activities that are supposed to play important roles in pathophysiology. In contrast, the upregulation was only shown in nucleic acid-binding activity. Taken together, potentially significant pathogenetic cellular processes were identified and showed that the downregulated functional profiling has a significant impact on the discovery of pathogenic pathway in leiomyoma. Also, the gene ontology analysis can overcome the complexity of expression profiles of cDNA microarray and two-dimensional protein analysis via its cellular process-level approach. Therefore, a valuable prognostic candidate gene with relevance to disease-specific pathogenesis can be found at cellular process levels.

Cell Communication↗

PubMed2002

Effects of organic matrix proteins on the interfacial structure at the bone-biocompatible nacre interface in vitro.

The biocompatibility and potential osteoinductivity of nacre have favored its use as a bone-grafting material. The present study is to investigate the interfacial structure at the bone-nacre interface resulting from organic matrix proteins, which emphasizes the mechanism of bone-bonding ability and biocompatibility of the shell tissues such as nacre and biogenic calcite. To understand the interfacial reaction, the zeta potential measurements, provide for a unique method to quantify the actual state of the interface in situ, were used for synthetic and biogenic calcium carbonate suspensions with respect to pH and the organic matrix as an additive. The zeta potentials and surface charge density show that the organic matrix proteins are main charge regulators, resulting in the stabilized tissue properties as compared with synthetic crystals. Also, in forming calcium carbonate crystals with the additives, the conformation of organic matrix has an important role in the understanding of the newly formed interfacial structure. The result provides the primary role of the organic matrix proteins in controlling the formation of interfacial structure and biocompatibility with bone as well as the stability of biogenic tissues. And it gives a new insight into the usefulness of zeta potential measurement to describe the in vivo interaction between the bone and implants.

Adsorption↗