• Biomolecules & Therapeutics
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• v.14 no.1
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• pp.30-35
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• 2006

Tissue-type plasminogen activator (t-PA) is a multidomain serine protease containing two kringle domains, TK1-2. Previously, Pichia-derived recombinant human TK1-2 has been reported as an angiogenesis inhibitor although t-PA plays an important role in endothelial and tumor cell invasion. In this work, in order to improve in vivo efficacy of TK1-2 through elimination of immune reactivity, we mutated wild type TK1-2 into non-glycosylated form (NE-TK1-2) and examined whether it retains anti-angiogenic activity. The plasmid expressing NE-TK1-2 was constructed by replacing $Asn^{l17}\;and\;Asn^{184}$ with glutamic acid residues. After expression in Pichia pastoris, the secreted protein was purified from the culture broth using S-sepharose and UNO S1-FPLC column. The mass spectrum of NE-TK1-2 showed closely neighboring two peaks, 19631.87 and 19,835.44 Da, and it migrated as one band in SDS-PAGE. The patterns of CD-spectra of these two proteins were almost identical. Functionally, purified NE-TK1-2 was shown to inhibit endothelial cell migration in response to bFGF stimulation at the almost same level as wild type TK1-2. Therefore, the results suggest that non-glycosylated NETK1-2 can be developed as an effective anti-angiogenic and anti-tumor agent devoid of immune reactivity.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.261-264
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• 2002

CHO (Chinese hamster ovary) cells were transfected with plasmids containing both cis-acting HRE (hypoxia response element) and CMV-promoter that controls tissue-type plasminogen activator (t-PA). CHO cells with HRE produced 16.2 fold higher t-PA concentration than CHO cells without HRE. It was noted that hypoxia strongly induced CHO cell apoptosis. which resulted in decrease of cell viability and protein production. In this study. by introducing Bcl-2, anti-apoptotic gene, we tried to recover cell viability and increase the protein production. When batch culture of both control cells without transfection of Bcl-2 and cells transfected with Bcl-2 were performed in the absence of CoCl ι hypoxia mimic condition. the cells with Bcl-2 were effected specific cell growth rates, maximum cell density. Immunoblotting assay showed Bcl-2 was recombinant with HRE dependent t- P A expression cassette, and their expression level was depended on hypoxia. By introducing Bcl-2, both cell viability and maximum cell density could be increased.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.516-524
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• 1997

Background : Cancer invasion and metastasis require the dissolution of the extracellular matrix in which several proteolytic enzymes are involved. One of these enzymes is the urokinase-type plasminogen activator(u-PA), and plasminogen activator inhibitors(PAI-1, PAI-2) also have a possible role in cancer invasion and metastasis by protection of cancer itself from proteolysis by u-PA. It has been reported that the levels of u-PA and plasminogen activator inhibitors in various cancer tissues are significantly higher than those in normal tissues and have significant correlations with tumor size and lymph node involvement. Here, we measured the concentration of plasma u-PA and PAI-1 antigens in the patients with lung cancer and compared the concentration of them with histologic types and staging parameters. Methods : We measured the concentration of plasma u-PA and PAI-1 antigens using commercial ELISA kit in 37 lung cancer patients, 21 benign lung disease patients and 24 age-matched healthy controls, and we compared the concentration of them with histologic types and staging parameters in lung cancer patients. Results : The concentration of u-PA was $1.0{\pm}0.3ng/mL$ in controls, $1.0{\pm}0.3ng/mL$ in benign lung disease patients and $0.9{\pm}0.3ng/mL$ in lung cancer patients. The concentration of PAI-1 was $14.2{\pm}6.7ng/mL$ in controls, $14.9{\pm}6.3ng/mL$ in benign lung disease patients, and $22.1{\pm}9.8ng/mL$ in lung cancer patients. The concentration of PAI-1 in lung cancer patients was higher than those of benign lung disease patients and controls. The concentration of u-PA was $0.7{\pm}0.4ng/mL$ in squamous cell carcinoma, $0.8{\pm}0.3ng/mL$ in adenocarcinoma, 0.9ng/mL in large cell carcinoma, and $1.1{\pm}0.7ng/mL$ in small cell carcinoma. The concentration of PAI-1 was $22.3{\pm}7.2ng/mL$ in squamous cell carcinoma, $22.6{\pm}9.9ng/mL$ in adenocarcinoma, 42 ng/mL in large cell carcinoma, and $16.0{\pm}14.2ng/mL$ in small cell carcinoma. The concentration of u-PA was 0.74ng/mL in stage I, $1.2{\pm}0.6ng/mL$ in stage II, $0.7{\pm}0.4ng/mL$ in stage IIIA, $0.7{\pm}0.4ng/mL$ in stage IIIB, and $0.7{\pm}0.3ng/mL$ in stage IV. The concentration of PAI-1 was 21.8ng/mL in stage I, $22.7{\pm}8.7ng/mL$ in stage II, $18.4{\pm}4.9ng/mL$ in stage IIIA, $25.3{\pm}9.0ng/mL$ in stage IIIB, and $21.5{\pm}10.8ng/mL$ in stage IV. When we divided T stage into T1-3 and T4, the concentration of u-PA was $0.8{\pm}0.4ng/mL$ in T1-3 and $0.7{\pm}0.4ng/mL$ in T4, and the concentration of PAI-1 was $17.9{\pm}5.6ng/mL$ in T1-3 and $26.1{\pm}9.1ng/mL$ in T4. The concentration of PAI-1 in T4 was significantly higher than that in T1-3. The concentration of u-PA was $0.8{\pm}0.4ng/mL$ in M0 and $0.7{\pm}0.3ng/mL$ in M1, and the concentration of PAI-1 was $23.6{\pm}8.3ng/mL$ in M0 and $21.5{\pm}10.8ng/mL$ in M1. Conclusions : The plasma levels of PAI-1 in lung cancer were higher than benign lung disease and controls, and the plasma levels of PAI-1 in T4 were significantly higher than T1-3. These findings suggest involvement of PAI-1 with local invasion of lung cancer, but it should be confirmed by the data on comparison with pathological staging and tissue level in lung cancer.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.695-703
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• 2006

The dissolved oxygen level of any cell culture environment has a critical effect on cellular metabolism. Specifically, hypoxia condition decreases cell viability and recombinant protein productivity. In this work, to develop CHO cells producing recombinant protein with high productivity, mammalian expression vectors containing a human tissue-type plasminogen activator (t-PA) gene with hypoxia response element (HRE) were constructed and stably transfected into CHO cells. CHO/2HRE-t-PA cells produced 2-folds higher recombinant t-PA production than CHO/t-PA cells in a $Ba^{2+}-alginate$ immobilized culture, and 16.8-folds in a repeated batch culture. In a non-aerated batch culture of suspension-adapted cells, t-PA productivity of CHO/2HRE/t-PA cells was 4.2-folds higher than that of CHO/t-PA cells. Our results indicate that HRE is a useful tool for the enhancement of protein productivity in mammalian cell cultures.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.257-260
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• 2002

Dissolved oxygen level of cell culture media has a critical effect on cellular metabolism, which governs specific productivity of recombinant proteins and mammalian cell growth However, in the cores of cell aggregates or cell-immobilized beads, oxygen level frequently goes below a critical level. Mammalian cells have a number of genes induced in the lower level of oxygen, and the genes contain a common cis-acting element (-RCGTG-), hypoxia response element (HRE). By binding of hypoxia inducible factor-l (HIF-I) to the HRE, promoters of hypoxia inducible genes are activated, which is a survival mechanism. In this work, to develop a CHO cell capable of producing recombinant proteins in immobilization and high density cell culture efficiently, mammalian expression vectors containing human tissue-type plasminogen activator (t-PA) gene controlled by HRE were constructed and stably transfected into the CHO cells. In $Ba^{2+}$ -alginate immobilization culture, CHO/pCl/dhfr/2HRE-t-PA cells produced 2 folds higher recombinant t-PA activity than CHO/pCl/dhfrlt-PA cells without $CoCl_2$ treatment. Furthermore, in repeated fed batch culture, productivity of t-PA in immobilized CHO/pCI/dhfr/2HRE-t-PA cells was 121 ng/ml/day, total production of 0.968 mg/day at 11 days culture while CHO/pCIIdhfrlt-PA cells was 22.8 ng/ml/day. All these results indicate that HRE is very useful for the enhancement of protein productivity in mammalian cell cultures.

• Journal of Ginseng Research
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• v.22 no.3
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• pp.216-221
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• 1998

We examined the anti-invasive activity of ginsenosides Rhl, Rha on the highly metastatic HT1080 human fibrosarcoma cell line. In vitro invasion assay showed ginsenoside Rhr reduced tumor cell invasion through a reconstituted basement membrane in a transwell chamber more than ginsenoside Rh1. Significant down-regulation of matrix metalloproteinase-9 (MMP-9) by ginsenosides Rh, and Rh2 was detected by Northern blot analysis. However, the expression of MMP-2 was not affected by Rh, and Rhr. The expression of tissue inhibitor of metalloproteinase-2 (TIMP-2) was increased by Rhl after 0.5, 1 or 3 day-treatment but reduced after 6 day-treatment. However, the expression of TIMP-2 was not changed by treatment with Rh2. Plasminogen activator inhibitor (PAI) and urokinase-type plasmlnogen activator (uPA) were not changed by treatment with Rh1 and Rh2 for 3 and 6 days. Quantitative gelatin-based zymography confirmed a markedly reduced expression of MMP-9 but MMP-2 after treatments with ginsenosides Rhl and Rha. These results suggest that down-regulation of MMP-9 contributes to the anti-invasive activity of ginsenosides Rhl and Rhr in the HT1080 cells.

• Reproductive and Developmental Biology
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• v.30 no.2
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• pp.135-141
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• 2006

The present study was conducted to investigate the effects of cumulus cells and porcine follicular fluid (pFF) on plasminogen activator (PA) activity and oocytes maturation in vitro in the pig. The cumulus-oocyte complexes (COCs) and denuded oocytes (DOs) were incubated in NCSU-23 medium with or without 10% pFF for 0, 24, or 48 hr. In the presence of cumulus cells, the proportions of oocytes matured to metaphase-II stage were significantly (P<0.05) higher in medium with pFF than without pFF (69.8 vs. 37.7%, respectively). When COCs and DOs were cultured in the presence of pFF, tissue-type PA (tPA), urokinase-type PA (uPA), and tPA-PA inhibitor (tPA-PAI) were observed in COCs, and PA activities were higher at 48 hr than 24 hr. When COCs and DOs were cultured in the absence of pFF, tPA and tPA-PAI were observed in COCs, and PA activities were increased as duration of culture increased. No PA activities were detected in DOs regardless of pFF supplementation. When porcine oocytes were cultured in the presence of pFF for 24 and 48 hrs, the activities of tPA-PAI, tPA, and uPA were observed in both COCs and DOs. In medium of absence of pFF, PA activities were observed in oocytes with cumulus cells only. On the other hand, three plasminogen-dependent lytic bands (tPA-PAI, tPA, and uPA) were observed in pFF cultures. Particularly uPA activity was higher than the other kinds of PA activity. When oocytes and cumulus cells were separated from porcine COCs at 0 hr of culture, tPA-PAI, tPA, and uPA were detected in cumulus cells at 48 hr of culture, but no PA activities were in DOs. The presence of pFF and cumulus cells in maturation medium stimulated not only nuclear and cytoplasmic maturation in porcine COCs, but also PA production by cumulus cells and COCs. It is possible that PAs produced by cumulus cells migrated through the gap junction between oocyte and cumulus cells. These results suggest that porcine oocytes have no ability to produce PA themselves.

• Reproductive and Developmental Biology
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• v.32 no.2
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• pp.89-95
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• 2008

The present study was undertaken to identify changes of plasminogen activators (PAs) in porcine oviductal epithelial cells (POECs) during the estrous cycle classified with post-ovulatory stages (Post-Ov), early to mid-luteal stages (Early-mid L) and pre-ovulatory (Pre-Ov) stages. The urokinase-type plasminogen activator (uPA) was only observed on day 5 and day 7 of culture in the POECs on all the estrous cycles and gradually increased according to increasing culture times, but not Early-mid L. In POECs-conditioned medium, uPA, tissue-type (tPA) and tPA-PA inhibitor (tPA-PAI) activity were observed at all culture times during estrous cycles. The uPA activity of POECs-conditioned medium on Post-Ov stage were significantly (p<0.05) decreased during prolonged cultures. On the other hand, the tPA activity of POECs-conditioned medium at Post-Ov stage was significantly (p<0.05) higher on day 5 than compared to the other days. Although was higher on day 1 at Post-Ov stage, the tPA-PAI activity of POECs-conditioned medium was significantly (p<0.05) higher on day 7 at all stage than that of day 5 of the culture. Taken together, these results suggest that uPA, tPA and tPA-PAI are produced by POECs, and the variations of the PAs activity are regulated in the different stages of the estrous cycle.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.333-340
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• 1999

Background: Plasminogen activator inhibitor-1(PAI-1) is known as the primary physiological inhibitor of tissue-type plasminogen activator(t-PA) in the plasma, and is present within the atherosclerotic vessels. Increased plasma levels of PAI-1 are one of the major disturbances of the hemostatic system in patients with diabetes and/or hypertension, and may have multiple interrelations with the important risk factors in the development of atherosclerosis. This study was performed to determine whether altered gene expression of PAI-1 occurs within the arterial wall, and thereby potentially contributing to the increase of cardiovascular risks associated with diabetes and/or hypertension. Material and Method: The aortic vascular smooth muscle cells of the rat were exposed to 22 mM glucose, angiotensin II, and insulin increased PAI-1 mRNA expression with the use of Northern blotting were examined. Also examined were the effects of 22 mM glucose, angiotensin II and insulin on the growth of the rat's aortic smooth muscle cells by using MTT assay. Result: Twenty-two mM glucose treatment increased the PAI-1 mRNA expression in a time- and dose-dependent manner. Aniotensin II treatment synergistically increased the glucose-induced PAI-1 mRNA expression. In contrast, addition of insulin attenuated the increase of 22 mM glucose and angiotensin II induced PAI-1 mRNA expression. Furthermore, treatment of 22 mM glucose, angiotensin II and insulin resulted in a significant increase in cell numbers. This study demonstrated that 22 mM glucose and angiotensin II have a synergistic effect in stimulating the PAI-1 mRNA expression and in the cell growth of the rat's aortic smooth muscle cells. Conclusion: Elevation of glucose and angiotensin II may be important risk factors in impairing fibrinolysis and developing atherosclerosis in diabetic patients.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1214-1222
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• 1998

Background : The intrapleural hypofibrinolysis is caused by mainly excessive concentration of pleural plasminogen activator inhibitor-1 antigen(PAI-1 Ag), which binds tissue type plasminogen activator. In pleural inflammation induced by sclerosing agents for pleurodesis, levels of pleural PAI-1 antigen increase in relation to decreasing D-dimer levels. It has been known that the pleural mesothelial cells have the capability of secreting PAI-1 Ag in response to inflammation in vivo. Therefore, we estimated whether pleural inflammation changes the balance between fibrinolytic and coagulative properties in exudative pleural effusions. Method : The thirty cases was included in our study. We determined the pleural levels of glucose, lactic dehydrogenase(LDH), pH and the counts of white blood cell(WBC), polymorpho leukocyte(PMN), lymphocyte as the parameters of pleural inflammation and cellular components of pleural fluid. The plasma level of fibrinogen in fluid and the neutrophil count in blood were determined. The levels of D-dimer, PAI-1 Ag and thrombinantithrombin III complex(TAT) were determined by ELISA(Behring, Marburg, Germany). Result : The causes of pleural effusion were as following : tuberculous in 14 cases, malignant in 10 cases and parapneumonic in 6 cases. The levels of pleural D-dimer, PAI-1 Ag and TAT was significantly higher than that of plasma(p<0..001). The severity of pleural inflammation did not correlated with pleural D-dimer, PAI-1 Ag, TAT and their plasma levels. But the level of pleural TAT correlated with pleural WBC and lymphocyte count. Conclusion : We found that the severity of pleural inflammations did not correlated with pleural D-dimer, PAI-1 Ag, TAT and the possibility of local production of PAI-1 antigen is present.