Human Immunodeficiency Virus-1 Tat 단백에 의한 인간 CD99유전자의 조절기전에 대한 연구

이유진,김예리,이미경,이임순,Lee, Eu-Gene,Kim, Ye-Ri,Lee, Mi-Kyung,Lee, Im-Soon 한국미생물학회 2008 미생물학회지 Vol.44 No.4

HIV에 감염된 환자의 경우 다양한 종류의 암이 발생하는 것으로 알려져 있다. 이러한 암종의 높은 발생률의 원인으로, 감염에 의한 면역세포의 감소 및 결핍과 같은 간접적인 이유 뿐 아니라, HIV 바이러스 단백질의 발현이 직접적으로 병의 발생에 관여한다는 보고가 있다. 본 연구에서는 HIV 환자에서 높게 나타나는 암의 발생에 대한 기전을 이해하기 위하여 HIV-1 Tat 유전자와, 다수의 암 발생과 관련이 있는 세포막단백 CD99와의 관계를 규명하였다. 먼저 CD99의 발현에 미치는 Tat의 영향을 알아보기 위하여 HIV-1 Tat 발현 안정화 세포주를 확립하고 Tat 단백에 의한 CD99 유전자의 발현 양상 변화를 분석하였다. 실험결과 Tat의 발현에 의하여 CD99 유전자의 발현이 활성화되는 것이 관찰되었으며 이와 반대로 STAT3의 발현은 낮아졌다. CD99 프로모터는 CpG 함량이 높기 때문에 Tat 단백이 DNA 메칠화를 통해서 CD99 유전자의 발현을 조절하는지 확인하기 위하여 methylation specific PCR을 수행하였고 Tat의 발현이 높은 곳에서 특이적으로 CD99 프로모터 부위가 탈메칠화되는 것을 발견하였다. Tat 발현 세포에서만 특이적인 발현 차이를 보이는 유전자 분석을 위한 Differentially Expressed Gene keratin 17과 collagen, type IV 증가됨이 확인되었다. 위의 결과는 HIV Tat 단백이 직접 세포 단백들을 조절하여 암을 발생시킬 수 있다는 보고를 뒷받침한다. HIV affects many organ systems. Patients with HIV infection have substantially increased risk of developing various cancers, primarily by opportunistic infection with oncogenic viruses due to their immunocompromised status. However, extensive evidence also indicates that the viral protein, Tat itself, may playas a major factor in the development of AIDS-related neoplasms. The molecular mechanism underlying Tat's oncogenic activity may include deregulation of cellular genes. Therefore, in this study, we examined the effect of HIV-l Tat on CD99 as one of the target cellular genes, which is a well-known tumor marker in several cancers. By using established HeLa clones that are stably expressing Tat, we found that CD99 is upregulated by endogenous Tat, whereas STAT3 is down regulated. Upon the screening of genes differentially expressed between Tat-stable cells and the control cells by using the gene fishing technique, DEG, we detected 3 genes which expression is affected by the presence of Tat. Furthermore, the methylation specific PCR analysis of the stably Tat expressing cell lines revealed that the CD99 promoter is de methylated in the presence of Tat. Taken together, these results open a potential role of CD99 in AIDS-related oncogenesis via epigenetic regulation by HIV-1 Tat.

Linkage Disequilibrium (LD) Mapping and Tagging SNP Selection of C-Fos Induced Growth Factor (Figf) Gene in Korean Population

Kim, Sook,Yoo, Yeon-Kyung,Jang, Hye-Yoon,Shin, Eun-Soon,Cho, Eun-Young,Kim, Eu-Gene,NamKung, Jung-Hyun,Yang, Jun-Mo,Lee, Jong-Eun The Korean Society of Toxicogenomics and Toxicopro 2006 Molecular & cellular toxicology Vol.2 No.1

We performed comprehensive SNP validation and linkage disequilibrium (LD) analysis of the c-fos induced growth factor (Figf) gene in Korean population. Out of 32 SNPs, only 9 SNPs were polymorphic in Korean population. Validated SNPs formed a single extended haplotype block with strong LD through the entire length of the gene. Tagging SNP analysis picked only 2 SNPs to represent most of the genetic variation information of the Figf gene. Our results demonstrate the utility of LD block and tagging SNP analysis for an efficient way of performing a candidate gene based association study.

Quantitative PCR for Etiologic Diagnosis of Methicillin-Resistant Staphylococcus aureus Pneumonia in Intensive Care Unit

( Sun Jung Kwon ),( Taeh Yeon Jeon ),( Dong Wook Seo ),( Moon Joon Na ),( Eu Gene Choi,),( Ji Woong Son ),( Eun Hyung Yoo ),( Chang Gyo Park ),( Hoi Young Lee ),( Ju Ock Kim ),( Sun Young Kim ),( Jae 대한결핵 및 호흡기학회 2012 Tuberculosis and Respiratory Diseases Vol.72 No.3

Background: Ventilator-associated pneumonia (VAP) requires prompt and appropriate treatment. Since methicillin- resistant Staphylococcus aureus (MRSA) is a frequent pathogen in VAP, rapid identification of it, is pivotal. Our aim was to evaluate the utility of quantitative polymerase chain reaction (qPCR) as a useful method for etiologic diagnoses of MRSA pneumonia. Methods: We performed qPCR for mecA, S. aureus-specific femA-SA, and S. epidermidis-specific femA-SE genes from bronchoalveolar lavage or bronchial washing samples obtained from clinically-suspected VAP. Molecular identification of MRSA was based on the presence of the mecA and femA-SA gene, with the absence of the femA-SE gene. To compensate for the experimental and clinical conditions, we spiked an internal control in the course of DNA extraction. We estimated number of colony-forming units per mL (CFU/mL) of MRSA samples through a standard curve of a serially-diluted reference MRSA strain. We compared the threshold cycle (Ct) value with the microbiologic results of MRSA. Results: We obtained the mecA gene standard curve, which showed the detection limit of the mecA gene to be 100 fg, which corresponds to a copy number of 30. We chose cut-off Ct values of 27.94 (equivalent to 1×104 CFU/mL) and 21.78 (equivalent to 1×105 CFU/mL). The sensitivity and specificity of our assay were 88.9% and 88.9% respectively, when compared with quantitative cultures. Conclusion: Our results were valuable for diagnosing and identifying pathogens involved in VAP. We believe our modified qPCR is an appropriate tool for the rapid diagnosis of clinical pathogens regarding patients in the intensive care unit.

MicroRNA Expression Profiles in Korean Non-Small Cell Lung Cancer

( Ji Woong Son ),( Young Jin Kim ),( Hyun Min Cho ),( Soo Young Lee ),( Jin Sung Jang ),( Jin Eun Choi ),( Jung Uee Lee ),( Min Gyu Kang ),( Yu Mi Lee ),( Sun Jung Kwon ),( Eu Gene Choi ),( Moon Jun N 대한결핵 및 호흡기학회 2009 Tuberculosis and Respiratory Diseases Vol.67 No.5

Background: MicroRNAs (miRNAs) play an important role in the regulation of cell proliferation, apoptosis, development and differentiation. Several studies have shown that aberrant expression of miRNAs is involved in cancer development and progression by regulating the expression of proto-oncogenes or tumor suppressor genes. In this study, we investigated miRNA expression profiles in Korean patients with non-small cell lung cancer (NSCLC). Methods: We performed miRNA microarray analysis containing 60∼65 bp oligonucleotide probes representing human 318 miRNAs and validated the results of the microarray with Northern blot analysis or quantitative RT-PCR. Next, we examined the correlation between miRNA expression and the target gene transcriptional profile using a human whole-genome-expression microarray. Results: We showed that 35 miRNAs were expressed differentially in the NSCLCs and corresponding non-malignant lung tissues. We showed that 35 miRNAs were expressed differentially in the NSCLCs and corresponding nonmalignant lung tissues. Thirteen of the 35 differentially expressed miRNAs were newly identified in the present study. Of the 35 miRNAs, 2 (miR-371 and miR-210) were over-expressed in lung cancers, and 33 miRNAs, including miR-145, were under-expressed in lung cancers. miR-99b expression consistently showed a negative correlation with FGFR3 expression. Conclusion: Albeit a small number of patients were examined, these results suggest that miRNA expression profiles in Korean lung cancers may be somewhat different from the expression profiles reported on lung cancers in Western populations. The findings suggest that miR-99b might be a tumor suppressor through its up-regulation of FGFR3.

Quantitative PCR for Etiologic Diagnosis of Methicillin-Resistant Staphylococcus aureus Pneumonia in Intensive Care Unit

Kwon, Sun-Jung,Jeon, Tae-Hyeon,Seo, Dong-Wook,Na, Moon-Joon,Choi, Eu-Gene,Son, Ji-Woong,Yoo, Eun-Hyung,Park, Chang-Gyo,Lee, Hoi-Young,Kim, Ju-Ock,Kim, Sun-Young,Kang, Jae-Ku The Korean Academy of Tuberculosis and Respiratory 2012 Tuberculosis and Respiratory Diseases Vol.72 No.3

Background: Ventilator-associated pneumonia (VAP) requires prompt and appropriate treatment. Since methicillin-resistant Staphylococcus aureus (MRSA) is a frequent pathogen in VAP, rapid identification of it, is pivotal. Our aim was to evaluate the utility of quantitative polymerase chain reaction (qPCR) as a useful method for etiologic diagnoses of MRSA pneumonia. Methods: We performed qPCR for mecA, S. aureus-specific femA-SA, and S. epidermidis-specific femA-SE genes from bronchoalveolar lavage or bronchial washing samples obtained from clinically-suspected VAP. Molecular identification of MRSA was based on the presence of the mecA and femA-SA gene, with the absence of the femA-SE gene. To compensate for the experimental and clinical conditions, we spiked an internal control in the course of DNA extraction. We estimated number of colony-forming units per mL (CFU/mL) of MRSA samples through a standard curve of a serially-diluted reference MRSA strain. We compared the threshold cycle (Ct) value with the microbiologic results of MRSA. Results: We obtained the mecA gene standard curve, which showed the detection limit of the mecA gene to be 100 fg, which corresponds to a copy number of 30. We chose cut-off Ct values of 27.94 (equivalent to $1{\times}10^4$ CFU/mL) and 21.78 (equivalent to $1{\times}10^5$ CFU/mL). The sensitivity and specificity of our assay were 88.9% and 88.9% respectively, when compared with quantitative cultures. Conclusion: Our results were valuable for diagnosing and identifying pathogens involved in VAP. We believe our modified qPCR is an appropriate tool for the rapid diagnosis of clinical pathogens regarding patients in the intensive care unit.

전분의 첨가가 자몽 종자 추출물 DF-100의 항균 활성에 미치는 영향

이유진,김지훈,김영식,정영재,김경범,정종문 수원대학교 기능성생명소재연구소 2003 자연과학연구논문집 Vol.2 No.1

Recent testimonials report grapefruit seed extract DF-100 to be successful in combating a variety of common infectious agents. This study investigated DF-100 for antimicrobial activites at containing 3% corn starch, 3% wheat flour and 0.5~5% starch contents to determine if antimicrobial activity of DF-100 keeps almost constant or is sometimes decreased by the addition of various types of starch. In our study, grapefruit seed extract DF-100 was tested for antibacterial properties against 5 strains. Gram-negative and gram-positive isolates {Escherichia coli, Bacillus cereus, Staphylococcus aureus, Candida albians, and Yeast (be often contaminated strain in confectionery factory)} were introduced into various dilutions of DF-100 (0, 250, 500, 1,000, 2,000, 4,000, 8,000, 16,000 ppm) for determination of antimicrobial activity. The antibacterial effect of the DF-100 appears to suppress the. growth of the 5 strains used for experiment. However, antimicrobial activity of DF-100 was reduced 1/4 to 1/16 when added into foods (such as bread, noodle, and biscuits) containing corn starch, wheat flour, or potato starch. It was evident that the antimicrobial activity DF-100 was decreased by addition of starch.

LB법을 이용한 TCNQ 박막의 물성 및 전기적 특성

金裕振,李榕洙 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

A study on the electrical conduction characteristics of the ultrathin organic films is one of the important factors for the development of molecular electronic devices. The Langmuir- Blodgett(LB) technique has recently been attracted interest as the a method of deposition ultrathin films. We have fabricated N-docosyl-N'-methyl viologen-(TCNQ-)₂(DMVT) anion radical LB film and investigated the physical properties and electrical conduction characteristics. We have measured infrared transmission-reflection spectra. The alkyl chain is found to be well-ordered with the tilt angle of 13˚ to the substrate surface normal and the TCNQ plane is tilted at 76˚ to the surface normal. In ESR spectrum, we confirmed that a half-amplitude linewidth is clearly dependent on both the incident angle and temperature, which indicates conducting species change their electron spin state. The in-plane conductivity of 31 layers is approximately 1.33×10?? S/cm. The ohmic behaviour was observed below 0.6 V and Schottky characteristics was observed in the range of 2.5∼6V, when current-voltage(I-V) characteristics was measured verically.

천연식품 추출 혼합물인 디콜을 이용한 마우스와 랫드에서의 LDL-콜레스테롤, 중성지질 및 체중 감소효과

김지훈,김경범,이유진,정종문 수원대학교 기능성생명소재연구소 2004 자연과학연구논문집 Vol.3 No.1

This study was performed to investigate the effects of natural source extracts, Dechol. The effects of Dechol were investigated an the blood LDL-cholesterol, triglyceride, and body weights in the Sprague Dawley rats, transgenic mice (B6, 129-Ldlr^(tm1Her)), and ICH mice. Hyperlipidemia was induced in SD rats and ICR mice by feeding them with high-fat food. Transgenic mice were tested by feeding them with normal food. All animal experiments were divided into 2 groups. One group was treated in drinking 0.5% Dechol whereas the other group was fed with tap water. Dechol-treated SD rat group could be returned to normal blood LDL-cholesterol level almost in 9 days. ICR mice determination of LDL-cholesterol level showed that the difference after 4 weeks between two groups was 43 mg/dl. Transgenic mice indicated that the blood cholesterol concentration in the subject group was decreasing everyday whereas the one in the control group was increasing, resulting in the difference of 280 mg/dl between two groups just after 20 day-treatment. These results suggest that Dechol may be efficiently used for primary prevention of cardiovascular diseases.

Hpall- Mspl Methylation Microarray를 이용한 비소세포폐암의 DNA Methylation Marker 발굴

권미혜 ( Mi Hye Kwon ),이고은 ( Go Eun Lee ),권선중 ( Sun Jung Kwon ),최유진 ( Eu Gene Choi ),나문준 ( Moon Jun Na ),조현민 ( Hyun Min Cho ),김영진 ( Young Jin Kim ),설혜정 ( Hye Jung Sul ),조영준 ( Young Jun Cho ),손지웅 ( Ji Woo 대한결핵 및 호흡기학회 2008 Tuberculosis and Respiratory Diseases Vol.65 No.6

연구배경: 유전자의 후생적인 변화(epigenetic alteration)는 악성종양의 병인론에 있어서 유전자 변이와 동등한 위치를 점하고 있다. 특히 종양억제 유전자의 전사 촉진(promoter) 부위에 발생하는 비정상적인 메칠화(methylation)는 유전자의 발현을 침묵화(silencing)하고, 결과적으로 유전자의 기능 소실을 일으키게 된다. 저자들은 CpG island와 HpaII site를 가지고 있으며 암화 과정에 관여할 것으로 생각되는 유전자에 대하여 HpaII-MspI methylation microarray를 이용하여 새로운 종양억제 유전자를 발굴하고자 하였다. 방법: 2005년 건양대학교 병원에서 수술한 비 소세포성 폐암 환자 10명에서 폐암조직과 상응하는 암 주변의 정상조직을 얻었으며, HpaII-MspI methylation microarray (Methyl-Scan DNA chip(R), Genomic tree, Inc, South Korea)를 이용하여 21개의 유전자에 대하여 DNA methylation profile을 분석하였다. 각각의 유전자에서 메칠화된 정도를 두 그룹에서 비교하였고, 정상 대조군으로 두 명의 젊고 건강한 기흉 환자에서 수술한 폐 조직에 대하여 methylation profile을 분석하였다. 결과: 21개의 대상 유전자 중 10개의 유전자에서 폐암조직, 폐암 주변 정상 조직, 대조군에서 모두 공통적으로 과메칠화 되었고, 나머지 11개의 유전자 중 APC, AR, RAR-b, HTR1B, EPHA3, CFTR의 6개의 유전자에서 대조군에서 메칠화가 없으며, 폐암조직에서 폐암 주변 정상 조직에 비하여 더 빈번하게 과메칠화 되었다. 결론: HTR1B, EPHA3, CFTR은 비소세포 폐암에서 후생적 변화로 발생하는 새로운 종양억제 유전자의 후보유전자로서의 가능성이 있을 것으로 생각한다. (Tuberc Respir Dis 2008;65:495-503) Background: Epigenetic alterations in certain genes are now known as at least important as genetic mutation in pathogenesis of cancer. Especially abnormal hypermethylation in or near promoter region of tumor suppressor genes (TSGs) are known to result in gene silencing and loss of gene function eventually. The authors tried to search for new lung cancer-specific TSGs which have CpG islands and HpaII sites, and are thought to be involved in carcinogenesis by epigenetic mechanism. Methods: Tumor tissue and corresponding adjacent normal tissue were obtained from 10 patients who diagnosed with non small cell lung cancer (NSCLC) and underwent surgery in Konyang university hospital in 2005. Methylation profiles of promoter region of 21 genes in tumor tissue & non-tumor tissue were examined with HpaII-MspI methylation microarray (Methyl-Scan DNA chip(R), Genomic tree, Inc, South Korea). The rates of hypermethylation were compared in tumor and non-tumor group, and as a normal control, we obtained lung tissue from two young patients with pneumothorax during bullectomies, methylation profiles were examined in the same way. Results: Among the 21 genes, 10 genes were commonly methylated in tumor, non-tumor, and control group. The 6 genes of APC, AR, RAR-b, HTR1B, EPHA3, and CFTR, among the rest of 11 genes were not methyl-lated in control, and more frequently hypermethylated in tumor tissue than non-tumor tissue. Conclusion: In the present study, HTR1B, EPHA3, and CFTR are suggested as possible novel TSGs of NSCLC by epigenetic mechanism.

MicroRNA-23a: A Novel Serum Based Diagnostic Biomarker for Lung Adenocarcinoma

Lee, Yu-Mi,Cho, Hyun-Jung,Lee, Soo-Young,Yun, Seong-Cheol,Kim, Ji-Hye,Lee, Shin-Yup,Kwon, Sun-Jung,Choi, Eu-Gene,Na, Moon-Jun,Kang, Jae-Ku,Son, Ji-Woong The Korean Academy of Tuberculosis and Respiratory 2011 Tuberculosis and Respiratory Diseases Vol.71 No.1

Background: MicroRNAs (miRNAs) have demonstrated their potential as biomarkers for lung cancer diagnosis. In recent years, miRNAs have been found in body fluids such as serum, plasma, urine and saliva. Circulating miRNAs are highly stable and resistant to RNase activity along with, extreme pH and temperatures in serum and plasma. In this study, we investigated serum miRNA profiles that can be used as a diagnostic biomarker of non-small cell lung cancer (NSCLC). Methods: We compared the expression profile of miRNAs in the plasma of patients diagnosed with lung cancer using an miRNA microarray. The data from this assay were validated by quantitative real-time PCR (qRT-PCR). Results: Six miRNAs were overexpressed and three miRNAs were underexpressed in both tissue and serum from squamous cell carcinoma (SCC) patients. Sixteen miRNAs were overexpressed and twenty two miRNAs were underexpressed in both tissue and serum from adenocarcinoma (AC) patients. Of the four miRNAs chosen for qRT-PCR analysis, the expression of miR-23a was consistent with microarray results from AC patients. Receiver operating characteristic (ROC) curve analyses were done and revealed that the level of serum miR-23a was a potential marker for discriminating AC patients from chronic obstructive pulmonary disease (COPD) patients. Conclusion: Although a small number of patients were examined, the results from our study suggest that serum miR-23a can be used in the diagnosis of AC.