• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.21-25
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• 2007

Background：Squamous cell carcinoma(SCC)of the palatine tonsils represents approximately 15-23% of all intraoral SCC. The most frequently reported risk factors for oropharyngeal cancer are smoking and alcohol. In a recent overview of HPV and tonsillar squamous cell carcinoma(TC), 51% contained HPV DNA, and HPV-16 being the most frequent type. We aimed to clarify whether HPV directly effects on the oncogenesis and biologic behavior of TC by comparison with infection prevalence, and physical status of virus. Material and Method：We used HPV genotyping DNA chip(Biocore, Korea, Seoul) arrayed by multiple oligonucleotide probes of L1 sequence of 26 types of HPV and HPV genotypes are identified by fluorescence scanner. The copy numbers of HPV E2 and E6 open reading frames(ORF) were assessed using a TaqMan-based 5'-exonuclease quantitative real-time PCR assay. The ratio of E2 to E6 copy numbers was calculated to determine the physical status of HPV-16 viral gene. Results：We observed a significant difference in HPV prevalence between 52 TCs and 69 CFTs(73.1% vs. 11.6%), and most of the HPVs were type 16(87.2%)and non-episomal(94.1%) state. Conclusions：This study regarding HPV infection prevalence and mechanism in the largest population of palatine tonsillar squamous cell carcinoma with chronic follicular tonsillitis revealed significant difference pf HPV prevalence between TC and CFT. Most of HPV were 16 type and integrated or mixed, HPV-16 integration could be directly related to tonsillar carcinogenesis.

• Korean Journal of Head & Neck Oncology
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• v.16 no.1
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• pp.14-19
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• 2000

Objectives: Epstein-Barr virus(EBV) is a B-lymphotrophic virus with a tumorigenic potential. EBV infection has been recognized as the main cause of nasopharyngeal carcinoma and Burkitt's lymphoma. Bcl-2 protein expression is known to be up-regulated by the EBV-latency associated antigen latent membrane protein(LMP). The aim of this study was to determine the incidence of EBV in squamous cell carcinomas of the larynx and the relationship between the presence of EBV and bcl-2 expression. Patients and Methods: From January 1994 to December 1977, 35 patients with primary squamous cell carcinoma of the larynx were studied. EBV genome DNA was surveyed by polymerase chain reaction(PCR) assay and then compared the results of in situ hybridization(ISH) for EBER1 using digoxigenin-tailed oligonucleotide probe. The expression of bcl-2 protein was studied by immunohistochemistry(IHC) using bcl-2 monoclonal antibody. Results: By PCR, EBV genome was detected in 22 of 35(62.9%) squamous cell carcinomas of the larynx. Nineteen of 35 cases(54.3%) showed a positive nuclear staining for EBER1 in tumor cells by ISH. Three cases showed positivity in inflammatory cells by ISH and one of them showed a positive staining of both tumor cells and inflammatory cells. Eighteen of 32 specimens(62.5%) were positive for bcl-2 protein. There was no significant correlations between the presence of EBV DNA and bcl-2 expression. Conclusions: It could be concluded that high incidence of EBV in the laryngeal cancer tissue may indicate a probable role of EBV in the development of laryngeal carcinoma.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.88-92
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• 2005

Aptamer is the single-stranded oligonucleotide which binds to various target molecules such as proteins, peptides, lipids and small organic molecules with high affinity and specificity. DNA aptamers specific for the $17{\beta}-estradiol$ were selected by SELEX (Systematic Evolution of Ligands by EXponential enrichment) process from a random DNA library. These DNA aptamers have a high affinity to $17{\beta}-estradiol$ as an endocrine disrupting chemical. Nanowell and $200{\mu}m$ gold electrode were used as substrate for DNA aptamer immobilization and electrochemical analysis. Especially, nanowell gold electrode was fabricated by e-beam lithography. The size of single nanowell is 130nm and 40,000 nanowells were deposited on one gold electrode. The immobilization method was based on the interaction between the biotinylated aptamer and streptavidin deposited on gold electrode previously. Immobilization procedure was optimized by surface plasma resonance (SPR) and electrochemical analysis. After the immobilization of DNA aptamer on streptavidin modified gold electrode, $17{\beta}-estradiol$ solution was treated on aptamer immobilized gold electrode. The current of gold electrode was decreased by the binding of $17{\beta}-estradiol$ to DNA aptamer immobilized on gold electrode. However, in negative control experiments of 1-aminoanthraquinone and 2-methoxynaphthalene, the current was rarely decreased. And more sensitive data was obtained from nanowell gold electrode comparing with $200{\mu}m$ gold electrode.

• Development and Reproduction
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• v.1 no.2
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• pp.189-202
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• 1997

The hypothalamic peptide GnRH plays a central role in the regulation of the mammalian reproductive axis. Recent studies suggested that GnRH stimulates or inhibits the ovarian steroidogenesis and gametogenesis directly. Our previous report indicated that GnRH gene is expressed in adult rat ovary as well as in hypothalamus and that the expressed GnRH may induce the follicular atresia and apoptosis of ovarian granulosa cells in rat. Therfore, we studied whether GnRH gene is expressed in the mouse fetal ovary, when the germ cells are degenerating by apoptosis during gonad diffeerentiation. Mouse fetal gonads were obtained on the 12, 15,18 and 20th day of gestation from the mother mice superovulated (10 IU PMSG and 10 IU hCG) and mated. The morphological changes of fetal ovaries were examined histochemically by hematoxylin-eosin staining. The fetal sex was confirmed by PCR methods for sexing. RT-PCR methods were used to examine the expression of GnRH gene and the sex steroid hormones were determined by conventional radioimmunoassays. The levels of estradiol (E) and progesterone (P) were increaseduntil 18th day of gestation and then E was decreased just before parturition. The morphological changes of fetal gonadal tissue sections showed the ovarian development and coincided with the result of PCR analysis for sexing using ovary- or testis- specific oligonucleotide primers. Immunoreactive GnRH in placenta was decreased gradually until the end of gestation but fetal brain and ovarian GnRH were increased. The level of GnRH gene expression was increased during fetal ovarian development from 12 till 18th day and decreased suddenly on 20th day just before birth. From these results, it is suggested that ovarian GnRh may play a regulatory role on the germ cell differentiation of fetal ovary.

• Journal of Life Science
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• v.14 no.3
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• pp.521-524
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• 2004

This experiment was carried out to analyze genetic characteristics and to develop the breed specific DNA marker for Cheju-native horse. If this marker contains high repetitive sequences, it is possible to convert a RAPD marker of interest into a single-locus PCR marker called a sequence characterized amplified region(SCAR). Twenty six Cheju-native horse and Fifty thoroughbred genomic DNA were pooled and PCR. were accomplished using 800 random primers. Comparing the pooled DNA from Cheju-native horse and thoroughbred, we found 9 primers which identified markers present in the pooled DNA from breed but absent in the other breed. Among 9 random primers, 6 primers were thoroughbred specific and 3 primers were Cheju-native horse specific. Testing individual horse revealed that 5 marker showed the similar band pattern between Cheju-native horse and Thoroughbred. However, 4 marker were wholly absent in breed while present in the other breed. UBC $126_{3500bp}$, UBC $162_{500bp}$, and UBC $244_{1200bp}$ was detected only Thoroughbred and UBC $562_{560bp}$was detected Cheju-native horse, respectively. After determining of the cloned breed-specific fragment sequence, we designed the SCAR-primers and carried out PCR. Compared to random primer, RAPD-SCAR primer didn't show significantly higher specific band. However, RAPD analysis is useful for genetic characterization of Cheju-native horse.

• Genomics & Informatics
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• v.10 no.1
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• pp.16-22
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• 2012

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by formation of multiple fluid-filled cysts that expand over time and destroy renal architecture. The proteins encoded by the $PKD1$ and $PKD2$ genes, mutations in which account for nearly all cases of ADPKD, may help guard against cystogenesis. Previously developed mouse models of $PKD1$ and $PKD2$ demonstrated an embryonic lethal phenotype and massive cyst formation in the kidney, indicating that $PKD1$ and $PKD2$ probably play important roles during normal renal tubular development. However, their precise role in development and the cellular mechanisms of cyst formation induced by $PKD1$ and $PKD2$ mutations are not fully understood. To address this question, we presently created $Pkd2$ knockout and $PKD2$ transgenic mouse embryo fibroblasts. We used a mouse oligonucleotide microarray to identify messenger RNAs whose expression was altered by the overexpression of the $PKD2$ or knockout of the $Pkd2$. The majority of identified mutations was involved in critical biological processes, such as metabolism, transcription, cell adhesion, cell cycle, and signal transduction. Herein, we confirmed differential expressions of several genes including aquaporin-1, according to different $PKD2$ expression levels in ADPKD mouse models, through microarray analysis. These data may be helpful in $PKD2$-related mechanisms of ADPKD pathogenesis.

• BMB Reports
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• v.40 no.4
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• pp.511-516
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• 2007

A glutathione S-transferase (GST) related to the phi (F) class of enzymes only found in plants has been cloned from the Oryza sativa. The GST cDNA was cloned by PCR using oligonucleotide primers based on the OsGSTF5 (GenBank Accession No. $\underline{AF309382}$) sequences. The cDNA was composed of a 669-bp open reading frame encoding for 223 amino acids. The deduced peptide of this gene shared on overall identity of 75% with other known phi class GST sequences. On the other hands, the OsGSTF5 sequence showed only 34% identity with the sequence of the OsGSTF3 cloned by our previous study (Cho et al., 2005). This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF5 formed a homo-dimer composed of 28 kDa subunit and its pI value was approximately 7.8. The expressed OsGSTF5 displayed glutathione conjugation activity toward 1-chloro-2,4-dinitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy)propane and glutathione peroxidase activity toward cumene hydroperoxide. The OsGSTF5 also had high activities towards the herbicides alachlor, atrazine and metolachlor. The OsGSTF5 was highly sensitive to inhibition by S-hexylGSH, benastatin A and hematin. We propose from these results that the expressed OsGSTF5 is a phi class GST and appears to play a role in the conjugation of herbicide and GPOX activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.51-54
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• 2007

Soybean has a morphological type with a broadened and flattened stem. Fasciation has been suggested as a new gene for soybean research. SSR marker linked to the $\Large f$ locus that controls fasciation phenotype has not identified within 10 cM. A mapping population consisting of 94 $F_2$ progenies was derived from a cross between wild type Clark (FF) and fasciation mutant C32 (${\Large f}{\Large f}$). The phenotype of $F_2$ individual plants was recorded at R2 and R3 growth stage from field. One-thousand 10-mer oligonucleotide RAPD primers and 29 SSR primers selected from the D1b+W of the soybean molecular linkage map were used. A genetic map was constructed from the segregating 35 RAPD, four SSR markers and one phenotypic(wild type/fasciation) marker. The segregation ratios of 3 : 1 observed in the $F_2$ population and the Chi-square values strongly suggest that the fasciation trait is controlled by a single recessive gene. Satt537 marker was linked to $\Large f$ locus at a distance of 9.6 cM. Assignment of the $\Large f$ locus to linkage group D1b+W and identification of markers can be used as an initial step for fine mapping of the $\Large f$ gene.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.110-116
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• 1998

The secY gene of Streptomyces lividans TK24 was cloned by the PCR method with synthetic oligonucleotide primers designed on the basis of the conserved regions of Ll5-secY-adk operon from E. coli, B. subtilis, and M luteus. The deduced amino acid sequences of the SecY are highly homologous to those of other known SecY. It has 46%, 43%, 57%, 44%, 42%,56%, 90% similarity to Escherichia coli, Bacillus subtilis, Micrococcus luteus, Bacillus licheniformis Staphylococcus carnosus, Brevibacterium flavum, Streptomyces scabies, respectively and almost the same with Streptomyces coelicolor, The gene organization of Ll5- SecY-Adk is also similar to those of other bacteria. SecY and Adk are very likely translationally coupled that is overlapping stop codon of SecY and start codon of Adk with one base pair, which is common structure among high GC content strains of gram positive bacteria.

• Biomedical Science Letters
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• v.10 no.2
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• pp.143-151
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• 2004

Matrix metalloproteinases (MMPs) are capable of degrading extracellular matrix, a process that is necessary for angiogenesis, tumor invasion and metastasis. Platelet-activating factor (PAP) increases angiogenesis, tumor growth and metastasis through nuclear factor (NF)-$\kappa$B activation. Based on these facts, the involvement of MMPs in PAF-induced pulmonary metastasis was investigated in murine sarcoma cells, MMSV-BALB/3T3. Messenger RNA expression and enzymatic activity of MMP-9 were assessed by RT-PCR and zymography, and cell migration and metastasis were done for the detection of MMP-9 functional activity. PAP induced mRNA expression and enzymatic activity of MMP-9, and its effects were either inhibited by the PAP antagonist, WEB 2170 or by the NF-$\kappa$B inhibitor, parthenolide, or p65 antisense oligonucleotide in a dose-dependent manner. In addition, PAF induced promoter activity of MMP-9, which was inhibited by WEB 2170, phenanthroline, NAC, PDTC. These results indicate that PAF induces mRNA expression and enzymatic activity of MMP-9 in NF-$\kappa$B dependent manner. Cell migration assay showed that PAF induced MMSV-BALB/3T3 migration, and its effect was significantly inhibited by treatment with phenanthroline. PAF enhanced pulmonary metastasis of murine sarcoma cells, MMSV-BALB/3T3 was also reduced by phenanthroline. These results suggest that PAF-enhanced cell migration and pulmonary metastasis is mediated through the expression of MMP. In conclusion, It is suggested that PAF enhances pulmonary metastasis by inducing MMP-9 expression via the activation of NF-$\kappa$B.