• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2259-2263
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• 2008

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.1-5
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• 2002

A fusion protein, consisting of a human epidermal growth factor (hEGF) as the recognition domain and human angiogenin as the toxin domain, can be used as a targeted therapeutic against breast cancer cells among others. The fusion protein was expressed as inclusion body in recombinant E. coli, and when the conventional, solution-phase refolding process was used the refolding yield was very low due to severe aggregation. It was probably because of the opposite electric charge at a neutral pH resulting from the vastly different pI values of each domain. The solid-phase refolding process that exploited the ionic interactions between ionic exchanger surface and the fusion protein was tried, but the adsorption yield was also very low, below $ 30\%$, regardless of the resins and pH conditions used. Therefore, to provide a higher ionic affinity toward the solid matrix, six lysine residues were tagged to the N-terminus of the hEGF domain. When heparin-Sepharose was used as the matrix, the adsorption capacity increased 2.5-3 times to about $88\%$. Besides the intrinsic affinity of angiogenin to heparin, the poly-lysine tag provided additional ionic affinity. And the subsequent refolding yield increased nearly 13-fold, from ca. $4.8\%$ in the conventional refolding of the untagged fusion protein to $63.6\%$. The process was highly reproducible. The refolded protein in the column eluate retained RNase bioactivity of angiogenin.

• Journal of Life Science
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• v.24 no.4
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• pp.337-342
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• 2014

Resveratrol (RSV), a natural polyphenolic compound, is a modulator for cell division and cell migration, and has diverse beneficial properties. Angiogenin (ANG) and vascular endothelial growth factor (VEGF) are considered to be important mechanisms for cell proliferation, angiogenesis, the formation of tubular structures, and migration. In this study, we investigated whether RSV has a migratory effect in HeLa cells. When cells were treated with $0{\sim}50{\mu}M$ of RSV for 24 hr, the expression of ANG and VEGF was significantly increased in a dose dependent manner measured by real-time PCR. Similarly, we performed time dependent experiments for $50{\mu}M$ RSV treated cells and identified the optimized time at 24 hr. The increased expression in RSV treated cells was confirmed by Western blot analysis. To examine the toxic effects of RSV at the determined conditions, MTT assays were performed. The viabilities were unchanged for $0{\sim}50{\mu}M$ RSV treated cells, while they decreased at $100{\mu}M$ RSV. To examine the effect of migration in RSV treated cells, we performed a wound-healing assay. The migratory rates were significantly enhanced in the RSV treated group. In this study, we found that RSV induces an increase in the expression of migration factors ANG, VEGF, and enhances cell migration for the determined conditions.

• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.229-230
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• 2015

신생혈관 형성은 기존에 존재하는 혈관으로부터 새로운 혈관을 형성하는 기작으로 정상 세포에서 상처 치유, 세포의 발생 및 성장에 관여한다고 알려져 있다. 더 중요한 것은 이 기작이 암의 성장 및 전이에서도 매우 중요한 역할을 하고 있다는 사실이다. 특히, 엔지오제닌(Angiogenin)이 신생혈관형성을 촉진하는 것으로 알려져있다. 이러한 주요 물질을 최신 바이오칩 기술 중 하나인 액적 기반 미세유체 시스템을 활용하여 1 나노리터 수준의 시료 내에 존재하는 엔지오제닌을 정량하는 기술을 개발함으로써 현재 일반적으로 사용되고 있는 정량 기술에 비해 시간뿐만 아니라 비용을 절감할 수 있음을 보여주었다. 이외에도 본 연구에서 개발한 액적 기반 미세유체 시스템 기술은 수은과 같은 중금속의 검출도 가능하기 때문에 환경 센서로의 활용 가능성을 보여준다.

• BMB Reports
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• v.44 no.11
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• pp.699-704
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• 2011

Nitric oxide (NO) is a critical biological mediator involved in numerous diseases. However, the short lifetime of this molecule in biological conditions can make its study in situ complicated. Here, we review some recent results on the role of NO in angiogenesis, obtained using a biocompatible microelectrode array. This simple system allowed for the quick and easy quantification of NO released from cells grown directly on the surface of the sensor. We have used this technology to demonstrate that angiogenin induces NO release, and to partially elucidate its intracellular transduction pathway.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.43-43
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• 1996

Bovine angiogenin (bAng) is a potent blood vessel inducing protein purified from cow milk. Fluorescence spectroscopy has been used to study the interaction of bAng with actin in 50 mM Tris-HCl, pH 7.5, and 1 mM CaCl$_2$ at 25$^{\circ}C$. Actin contains four tryptophans but bAng contains no tryptophans. A 50% decrease in intrinsic fluorescence accompanied formation of the bAng/actin complex. (omitted)

• BMB Reports
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• v.29 no.4
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• pp.353-358
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• 1996

Bovine angiogenin (bAng) is a potent blood vessel inducing protein purified from cow In ilk. fluorescence spectroscopy has been used to study the interaction of bAng with actin in 50 mM Tris-HCl pH 7.5, and 1 mM $CaCl_2$ at $25^{\circ}C$. Actin contains four tryptophans but bAng contains no tryptophans. A 50% decrease in intrinsic fluorescence accompanied formation of the bAng/actin complex. By contrast, the interaction of RNase A, a homologous protein to bAng, with actin results in about 10% quenching of the fluorescence. Fluorescence titration experiments were performed by adding increasing concentrations of bAng (0~1.0 ${\mu}M$) to a constant concentration of actin (0.1 ${\mu}M$), and the dissociation constant $K_d$ for the bAng/actin complex and the stoichiometry n were measured as $20{\pm}1$ nM and $1.0{\pm}0.1$ respectively. These results suggest that the interaction between bAng with actin is specific and that quenching of actin fluorescence has occurred in the bAng/actin complex. The bAng binding sites of actin are discussed in the results of this study, and we propose that Trp-80 in the small domain of bovine actin is responsible for the bAng/actin binding.

• KSBB Journal
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• v.17 no.2
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• pp.153-157
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• 2002

A fusion protein, consisting of a human epidermal growth factor as the recognition domain and human angiogenin as the toxin domain, can be used as a targeted therapeutic against breast cancer cells among others. The fusion protein was expressed as an inclusion body in recombinant E. coli, yet when the conventional solution-phase refolding process was used the refolding yield was very low due to severe aggregation, probably because of the opposite surface charge resulting from the vastly different pl values of each domain. Accordingly the solid-phase refolding process, which exploits the ionic interactions between a solid matrix and the protein, was tried, however the ionic binding yield was also very low regardless of the resins and pH conditions used. Therefore, to provide a higher affinity toward the solid matrix, six Iysine residues were tagged to the N-terminus of the hEGF domain. When cation exchange resins, such as heparin- or CM-Sepharose, were used as the matrix, the adsorption capacity increased 2.5~3-fold and the subsequent refolding yield increased nearly 15-fold compared to the conventional process. A similat result was also obtained when an Ni-NTA metal affinity resin was used.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.197-203
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• 2001

A fusion protein, consisting of human epidermal growth factor as a recognition domain and human angiogenin as a toxin domain, can be used as a targeted therapeutic against breast cancer cells among others. The fusion protein was expressed as inclusion body in recombinant E. coli, and when the conventional, solution-phase refolding process was used the refolding yield was very low due to severe aggregation, probably due to the opposite surface charge due to vastly different pI values of each domain. Solid-phase refolding process exploiting ionic interactions between the solid matrix and the protein was tried, but the ionic binding yield was very low regardless of the resins and pH conditions used. To provide higher affinity toward the solid matrix, six lysine residues were tagged to the N -terminus of the hEGF domain When the cation exchange resins such as heparin- or CM-Sepharose were used as the matrix, the adsorption capacity increased 2.5-3 times and the subsequent refolding yield increased nearly IS times compared to the conventional process.

• Korean Journal of Acupuncture
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• v.26 no.2
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• pp.27-38
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• 2009

Objectives: Rheumatoid arthritis (RA) is a chronic autoimmune disease, principally characterized by synovial inflammation of the joints. We previously reported the effect of acupuncture for RA, but the mechanism is still unclear. Various factors such as oxidative stress and angiogenesis were involved in the pathogenesis of RA, and recently, it has also been reported that cytokines also play a major role in RA. Thus, we investigated whether acupuncture could induce any changes in the levels of cytokines including vascular endothelial growth factor (VEGF), angiogenin and epidermal growth factor (EGF) as well as erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), and rheumatoid factor (RF) in the sera of RA patients. Methods: The forty three patients who met the American College of Rheumatology (ACR) criteria for RA recruited. The acupuncture group (n=21) underwent 14 sessions of partially individualized acupuncture treatment for 6 weeks, and the control group had no treatment (n=13) over the same periods. We evaluated ESR, CRP and RF. In addition, to find out the mechanism of acupuncture, we assessed the changes of the cytokine activities using protein cytokine array in the sera of the patients. Results: Acupuncture significantly decreased the levels of ESR and CRP, but RF were not changed after 6-week acupuncture treatments. Moreover, acupuncture reduced the levels of VEGF, angiogenin and EGF in the sera of the patients. Interestingly, they were related with angiogenesis, which is an important process in the pathogenesis of RA. The levels of oncostatin, interleukin(IL)-$1{\alpha}$, IL-8, leptin, monocyte chemotactic protein-1, macrophage-derived chemokine, macrophage inflammatory proteins-1, platelet-derived growth factor BB and RANTES were not changed significantly. Conclusions: The effect of acupuncture for reliving RA symptoms can be partially explained by inhibition of angiogenesis factors in the sera of the RA patients.