• IMMUNE NETWORK
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• 제1권1호
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• pp.77-86
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• 2001

Background: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell. Methods: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. Results: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patients captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. Conclusion: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제22권4호
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• pp.373-382
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• 2000

Individual genetic susceptibilities to cancers may result from several factors including differences in xenobiotics metabolism to chemical carcinogens, DNA repair, altered oncogenes and suppressor genes, and environmental carcinogen exposures. Among them, genetic polymorphisms of metabolizing enzymes to chemical carcinogens have been recognized as a major important host factors in human cancers. They have two main types of enzymes: the phase I cytochrome P-450 mediating enzymes (CYPs) and phase II conjugating enzymes. The purpose of this study is to determine the frequencies of genotypes of phase I (CYP1A1 and CYP2E1) and phase II (NAT2) metabolizing enzymes in healthy control and head and neck cancer patients of Korean and to identify the relative high risk genotypes of these metabolizing enzymes to head and neck cancer in Korean. The author has analyzed 132 head and neck cancer patients and 113 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results were as following; 1. The frequencies of genotypes of CYP1A1, CYP2E1 and NAT2 in healthy control were as following; CYP1A1 exon 7 polymorphism; Ile/Ile: Ile/Val: Val/Val = 59.3%: 36.3%: 4.4% CYP2E1 Pst I polymorphism, C1/C1: C1/C2: C2/C2 = 61.1%: 32.1%: 6.2% NAT2 polymorphism; F/F: F/S: S/S = 43.4%: 48.7%: 8.0% 2. In analysis of phase I enzyme, Val/Val genotype in CYP1A1 exon 7 polymorphism and C2/C2 genotype in CYP2E1 Pst I polymorphism were associated with relative high risks to head and neck cancers (Odds' ratio: 2.09 and 1.37, respectively). 3. Among the genotypes of NAT2 enzyme polymorphism, S/S genotype of NAT2 enzyme had 1.03 times of relative risk to head and neck cancers. 4. In combined genotyping of CYP1A1, CYP2E1, and NAT2 enzymes polymorphisms, the patients with Val/Val and C1/C1, C2/C2 and fast acetylator, and Val/Val and fast acetylator had higher relative risks than the patients with each baseline of combined genotypes (Odds' ratio: 2.82, 1.98 and 2.1, respectively). These results suggest the combined genotypes of Val/Val and C1/C1, C2/C2 and fast acetylator, and Val/Val and fast acetylator were more susceptible to head and neck cancers in Korean. And genotyping of metabolizing enzymes could be useful for predicting individual susceptibility to head and neck cancer.

• 사상체질의학회지
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• 제9권2호
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• pp.163-173
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• 1997

본 연구는 사상의학의 객관화 및 그 임상활동에 관한 유용한 자료를 제공함을 목적으로, 사상체질진단법에 의해서 분류된 태음인, 소양인, 소음인 그룹에 대하여 현재 유전적 분석 연구에 많이 사용되는 Amp-FLP법을 이용하여 VNTR인 MCT118(D1S80)과 STR중 3종의 locus (THO1, vWA, CSF1PO)를 대상으로 alleledistribution을 조사 작성하였다. 그리고 이러한 결과들은 Chi-square test를 통하여 통계학적인 유의성이 검토되었다. MCT118과 THO1은 각 체질별 집단의 특이성을 대변할 만한 유의적인 요소가 없는 것으로 나타났으나, vWA의 경우는 각 체질집단 중 소양인(0.002056)과 소음인($2.41{\times}10^{-10}$) 집단이 유의수준인 0.05보다 현저히 낮은 p-value를 나타내었다. 또한, CSFIPO에서도 소음인 집단이 $4.65{\times}10^{-17}$의 매우 낮은 p-value를 나타내었다. 따라서, 유의성 있는 차이를 보여준 vWA와 CSF1PO의 경우, 충분한 크기의 표본을 가지고 유전자 분석을 실시하여 위와 통일한 결과를 얻는다면 체질간 유전적 차이를 보여주는 지표로 사용될 수 있을 것으로 기대된다.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.86-86
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• 2003

Research has been in progress for more than a decade to production of useful proteins by genetic modification in cattle. However, the levels of protein production in transgenic cattle have been reported very low. To enhance protein production in transgenic animal, we tried homologous recombination to donor cells for production of transgenic clone cattle through nuclear transfer procedure. Thus, we constructed the two targeting vectors of human thrombopoietin (TPO) at bovine $\beta$-casein locus using homologous recombination with 13.6 kb and 9.6 kb homology. In two targeting vectors, positive selection was through the neomycin resistance gene and negative selection was by the diphtheria toxin (DT). Gene targeting was attempted in bovine embryonic fibroblasts (bEF) and bovine ear skin fibroblasts (bESF). To determine the most appropriate concentration of neomycin for bEF and bESF, G4l8 resistance was confirmed by culturing the cells in various concentrations of the drug and both of the cells were optimally selected at $900 \mu g/ml$ of neomycin. The transfected bEF and bESF by the targeting vectors were colonized efficiently at the ratio of DNA to transfection reagent such as $4 \mu g$:2 ${mu}ell$ and $1 \mu g$:$2 \mu l$. Comparing number of healthy clones from passage 4 to passage 8, bESF (17%) persist in culture for much longer than bEF (6%). The two gene-targeted bESF clones of 30 random-integrated clones with 9.6 kb homology length were confirmed, however, nothing was out of 72 random integration clones with 13.6 kb homology length, The DT also worked more efficiently in clones transfected with the vector of 9.6 kb homology length. Our data suggests that the choice of donor cell for long culture period should be considered to obtain targeted cell clone, and the gene-targeting frequency and the DT working efficiency are dependent on the length of target homology.

• 한국식품영양과학회지
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• 제38권10호
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• pp.1317-1323
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• 2009

당유자 과피(GGP) 80% 에탄올 추출물을 4종의 암세포에 (피부암, 대장암, 유방암 및 혈액암) 처리하여 증식 억제 활성을 측정한 결과, 혈액암 HL60 세포에서 높은 증식 억제 활성을 보였다. 이에 CGP 추출물이 HL60 세포에 대한 apoptosis 유도에 따른 세포 증식 억제 활성을 조사하였다. Apoptosis 유도의 첫 단계인 막 투과성을 측정한 결과, confocal image와 flow cytometry에서 CGP를 처리하였을 때 탈분극 현상에 따른 막 투과성이 증가하였고 세포내 핵을 hoechst 33342를 이용하여 염색하였을 때 apoptosis가 일어났을 때 나타나는 전형적인 형태의 apoptotic body가 농도 의존적으로 증가하는 것을 확인할 수 있었으며 flow cytometry를 통하여 세포 주기를 측정하였을 때 DNA-hypodiploid 형태의 sub-G1가 CGP 농도 의존적으로 증가하는 것을 확인할 수 있었다. Apoptosis 유도 기전을 western blot으로 측정한 결과를 보면, CGP 추출물을 혈액암 HL60 세포에 처리하였을 때 Bcl family의 anti-apoptotic Bcl-2 단백질의 감소와 pro-apoptotic Bax 단백질의 증가로 인하여 하위 기전인 caspase-3가 활성화되었으며, 이 활성화로 인하여 apoptosis 유도에 직접적으로 관여하는 PARP 단백질을 활성화시키면서 apoptosis를 유도하였다. 따라서 당유자 과피는 항암과 관련되어진 기능성식품 및 소재 개발 원료로서 개발이 가능하리라고 사료된다.

• BMB Reports
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• 제45권9호
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• pp.532-537
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• 2012

P18, a member of the INK4 family of cyclin-dependent kinase inhibitors, is a tumor suppressor protein and plays a key cell survival role in a variety of human cancers. Under pathophysiological conditions, the INK4 group proteins participate in novel biological functions associated with neuronal diseases and oxidative stress. Parkinson's disease (PD) is characterized by loss of dopaminergic neurons, and oxidative stress is important in its pathogenesis. Therefore, we examined the effects of PEP-1-p18 on oxidative stress-induced SH-SY5Y cells and in a PD mouse model. The transduced PEP-1-p18 markedly inhibited 1-methyl-4-phenyl pyridinium-induced SH-SY5Y cell death by inhibiting Bax expression levels and DNA fragmentation. Additionally, PEP-1-p18 prevented dopaminergic neuronal cell death in the substantia nigra of a 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine-induced PD mouse model. These results indicate that PEP-1-p18 may be a useful therapeutic agent against various diseases and is a potential tool for treating PD.

• BMB Reports
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• 제42권7호
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• pp.444-449
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• 2009

Different neurodegenerative disorders like prion disease, is caused by protein misfolding conformers. Reverse-transfected cytosolic prion protein (PrP) and PrP expressed in the cytosol have been shown to be neurotoxic. To investigate the possible mechanism of neurotoxicity due to accumulation of PrP in cytosol, a PrP mutant lacking the signal and GPI (CytoPrP) was introduced into the SH-SY5Y cell. MTT and trypan blue assays indicated that the viability of cells expressing CytoPrP was remarkably reduced after treatment of MG-132. Obvious apoptosis phenomena were detected in the cells accumulated with CytoPrP, including loss of mitochondrial transmembrane potential, increase of caspase-3 activity, more annexin V/PI-double positive-stained cells and reduced Bcl-2 level. Moreover, DNA fragmentation and TUNEL assays also revealed clear evidences of late apoptosis in the cells accumulated CytoPrP. These data suggest that the accumulation of CytoPrP in cytoplasm may trigger cell apoptosis, in which mitochondrial relative apoptosis pathway seems to play critical role.

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.101-108
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• 2000

자궁내막증은 흔한 부인과적 질병이며 여성 불임의 한 원인이 되나 그 발생 원인에 대하여서는 아직 논란의 여지가 많다. 최근 월경혈의 역류에 의하여 자궁내막증이 생긴다는 가설이 가장 유력한데 자궁내막증 환자가 정상여성에서보다 역류되는 월경혈의 양이 많거나 침습성이 강한 것이 자궁내막증의 발생원인이 될 수 있다는 이론들이 소개되었다. Pleitrophin (PTN)이나 midkine(MK)은 성장 및 분화에 관여하는 인자로서 여러 종류의 악성 종양에서 그 발현이 보고되어있으며 종양화 (carcinogenensis), 맥관형성 (angiogenesis), plasminogen activator의 활성화 증가 등에 관여한다고 보고된 바 있다. 이에 자궁내막증 환자의 자궁 내막과 대조군의 자궁내막에서 PTN과 MK mRNA의 발현의 차이를 quantitative competitive RT PCR로 비교하였다. 그 결과 자궁내막증 환자의 황체기 자궁내막에서 대조군의 자궁내막에 비하여 PTN과 MK의 발현이 높게 나타났다. 이러한 PTN과 MK의 발현의 증가로 자궁내막증 환자의 자궁내막이 복강 내에서 더욱 쉽게 맥관형성을 하고 성장이 촉진되어 자궁내막증이 발생될 것으로 생각되어 PTN과 MK가 자궁내막증의 초기 발생과정에 관여할 가능성이 있다.

• 한국가축번식학회지
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• 제22권4호
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• pp.419-424
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• 1998

토끼 수정란의 전핵에 MT-hGH 유전자를 주입하고 핵이식 기법으로 형질전환 복제수정란의 생산효율과 PCR 검색으로 복제수정란에서 유전자존재 여부를 조사한 바 다음과 같은 결론을 얻었다. 1. MT-hGH 유전자를 주입하여 8- 및 16- 세포기로 자란 수정란을 공핵란으로 사용하여 핵이식을 실시하였던 바, 세포융합률은 각각 60.0%, 62.8% 로 비슷하였으나 정상수정란을 공급핵으로 사용한 80.4% 보다 유의적으로 낮은 융합률을 보였다. 그러나 이들 복제수정란의 체외발달률은 처리군간에 유의적인 차이는 인정되지 않았다. 2. 유전자 주입 후 8- 및 16- 세포기로 자란 수정란의 할구를 이용하여 핵이식으로 복제하고 체외에서 배반포까지 자란 수정란을 PCR -screening으로 유전자를 검출한 결과, 각각 23% 와 33% 의 유전자 양성 수정란을 감별하였다.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보학 국제심포지엄
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• pp.129-137
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• 2001

We used cDNA microarrays to assess gene expression profiles in 60 human cancer used in a drug discovery screen by the National Cancer Institute. Using these data, we linked bioinformatics and chemoinformatics by correlating gene expression and drug activity pattens in the NCI60 lines. Clustering the cell lines on the basis of gene expression yielded relationships very different from those obtained by clustering the cell lines on the basis of their response to drugs. Gene-drug relationships for the clinical agents 5-fluorouracil and L-asparaginase exemplify how variations in the transcript levels of particular genes relate to mechanisms of drug sensitivity and resistance. This is the first study to intergrate large databases on gene expression and molecular pharmacology.