• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.169-179
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• 1997

서론 : Laminin의 수용기로 알려진 Integrin $\alpha6\beta4$의 세포내 표현 정도는 편평상피암을 위시한 여러 악성종양의 전이능력 및 예후와 밀접한 상관관계가 없다고 알려져 있다. 이 Integrin은 Laminin과 같은 세포와 리간드와 결합하면 상피세포의 기저막 지주 구조물인 hemidesmosome의 세포체질 요소(cytoskeletal element)와 연관되어 그 결과 세포의 기저막과 세포내 케라틴을 연결하는 역할을 한다. Integrin $\alpha6\beta4$는 구조적으로 다른 많은 integrin들과 달리 $\beta$4의 세포질내 영역(cytoplasmic domain)이 특징적으로 크다. 이 세포질내 영역 $\beta$4 integrin의 기능은 아직 밝혀지지 않고 있으나 아마 세포 성장의 신호전달 및 악성종양의 특징인 침윤 전이에 관련할 것으로 보아지고 있다. 재료 및 방법: 저자들은 우선 $\beta$4 integrin의 wild type s-DNA와 $\beta$4 세포질내 영역(cytoplasmic domain) 및 $\beta$4의 tyrosine 인산화 반응 부위가 각각 결손된 c-DNA를 PCR을 통하여 합성하여 pRc/CMV 벡터에 삽입한 후 원래 $\beta$4 integrin의 발현이 결집된 인간 방광암 세포에 Calcium phosphate precipitation 방법으로 주입(transfection)시켜 형질변환된 세포를 면역형광법, Flow cytometry 및 Immunoprecipitation 방법으로 클로닝하여 wild type $\beta$4-full length(Clone FL), truncated $\beta$4-cytoplasmic domain(C1one CD), 및 mutated $\beta$4-tyrosine phosphorylation site (Clone M)을 얻었다. 암 세포의 부착 및 침투 능력의 기능적 연구로 모노 클로날 항체와 fibronectin, laminin, Matrigel을 단백질 기질로 사용하였으며 결과 비교를 위하여 pRc/CMV 벡터만 주입시켰던 클로운과 방광암 세포주를 $\beta$4 integrin 음성 대조군으로 또한 이 Integrin의 높은 발현을 보이는 두경부 편평상피암 세포주를 양성 대조군으로 이용하였다. 결과 : 세포부착능력에 있어서 온전한 $\beta$4 cytoplasmic domain이 존재하는 클로운이 laminin에 강한 부착능력을 보였으나 fibronectin의 부착정도는 $\beta$4 integrin의 표현정도와 관계없이 모든 클로운에서 비슷하였다. Matrigel을 투과하는 암세포 침윤 능력에서는 $\beta$4 integrin의 표현이 존재하는 클로운들이 투과 능력이 높았으나 세포외 리간드가 없는 control membrane을 사용하였을 때와 비교하여 투과능력의 차이를 보이지 않았다. 결론 : 유전자 주입(transfection) 방법으로 integrin의 다양한 클로운의 합성이 가능하여 이 Integrin의 암 세포의 부착 및 침투 능력에서의 기능을 규명 할 수 있게 한다. $\beta$4 integrin은 편평상피 암세포의 부착에 있어서 세포외 리간드 laminin과 특이 결합하여 부착 능력을 높이는 중요한 역할을 하며 편평상피 암세포의 침투에 있어서는 $\beta$4 integrin의 표현이 침투 능력을 높이는 역할을 하나 이때에는 laminin과 같은 리간드와의 특이 결합에 의존하지는 않는 것으로 사료된다.

• Journal of Korean Neurosurgical Society
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• v.57 no.5
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• pp.329-334
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• 2015

Objective : To comparatively investigate the expression of several integrins in specimens of human bone metastases and degenerative bone tissue. Methods : Degenerative cancellous tissue was obtained from a sample of human degenerative spine. Thirteen human specimens were obtained from metastatic spine tumors, whose primary cancer was colon cancer (n=3), hepatocellular cancer (n=3), lung cancer (n=4), and breast cancer (n=3). The expression of vimentin and integrins ${\alpha}v$, ${\beta}1$, and ${\beta}3$ was assessed in metastatic and degenerative specimens by immunohistochemistry and real-time reverse transcription-polymerase chain reaction (qRT-PCR). Results : Immunohistochemical staining showed that vimentin and integrin ${\alpha}v$ was broadly expressed in all tissues examined. By contrast, integrin ${\beta}1$ was weakly expressed only in 38.4% (5/13) of tissues. Integrin ${\beta}3$ was consistently negative in all cases examined. qRT-PCR analysis showed that vimentin gene expression was higher in all metastatic specimens, as compared to degenerative bone. The gene expression of integrin ${\alpha}v$ in breast specimen was significantly higher than others (p=0.045). The gene expression of integrin ${\beta}1$ was also higher in all metastatic specimens than in degenerative bone tissue. The gene expression of integrin ${\beta}3$ was variable. Conclusion : Spinal metastatic tumors have mesenchymal characteristics such as increased expression of vimentin. The increased expression of integrin ${\alpha}v$ and ${\beta}1$ in spine metastatic tumors suggests that adhesive molecules such as integrin may have implications for the prevention of spine metastasis.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.55-66
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• 1998

Pathophysiological mechanism of hemorrhagic fever with renal syndrome (HFRS) is not fully understood. Major clinical findings of HFRS patients are widespread hemorrhage, acute renal failure and shock. Basic lesion is vascular injury with microvascular hemorrhage and relatively little inflammation. According to autopsy findings, renal medulla shows focal hemorrhage, tubular necrosis and interstitial mononuclear infiltrates. The predominant cell type in the renal and pulmonary interstitium is a fibroblast and it participates in the healing process at the injury site by secreting a large amount of extracellular matrix proteins. Cultured human lung fibroblasts and Mongolian gerbil fibroblasts were known to be good host cells for the hantaan virus. It is possible that not only the endothelial cell but also the fibroblast is a target of Hantaan virus and the fibroblast might be involved in the pathogenesis and the healing process in HFRS. Integrins are adhesion molecules, and act as receptors for many extracellular matrix proteins. Recently, there are many reports that cell surface integrins influence on some viral infections or reversely viruses influence on the expression of integrins. The ${\alpha}_5{\beta}_1$ integrin is a major receptor for the fibronectin which is an important extracellular matrix protein secreted by fibroblasts. In this study, the role of ${\alpha}_5{\beta}_1$ integrin in the infection of Hantaan virus was examined by using anti-${\alpha}_5{\beta}_1$, integrin, anti-${\alpha}_5$ integrin and anti-${\beta}_1$, integrin antibodies in chicken embryo fibroblasts (CEF) and Mongolian gerbil fibroblasts(MGF). The treatment of anti-${\alpha}_5{\beta}_1$, integrin antibody in CEF reduced the virion titers 26.8% and the amount of nucleocapsid N protein 32.6% when compared with control CEF. When MGF were treated with anti-${\alpha}_5$, anti-${\beta}_1$ and anti-${\alpha}_5{\beta}_1$ integrin antibodies, virion titers were reduced by 26.5%, 29.4% and 28.7% and the amount of nucleocapsid N protein were reduced by 65.2%, 59.7% and 72.6%. These results suggested that ${\alpha}_5{\beta}_1$ integrin might act as a receptor for the Hantaan virus or blocking of ${\alpha}_5{\beta}_1$ integrin influences on the viral replication in CEF and MGF. It is also possible that the blocking of only one subunit of integrin represents similar results in that of whole molecule.

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.592-596
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• 1994

The interaction between fibronectin (FN) and its receptors controls cell attachment and migration, two crucial events during monocyte development and differentiation. To investigate the functional role of FN and its receptor, we have studied adhesion of monocyte to two different regions of FN (38- and 85-kDa domain), as well as the expression of the integrin during monocle differentiation. Anti-integrin Rl subunit antibody completely blocked the attachment of FN-coated latex beads to macrophage, but the effect of anti-integrin u4 antibody was much less significant. Rat monocyte expressed integrin $u4\beta1$ predominantly, while macrophage expressed $\alpha5\beta1$ as analyzed tv flow cvtometer and western blot. From these results, it can be suggested that these two integrins plan different roles during monocyte differentiation.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.102-102
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• 2002

Heparin-bindin epidermal growth factor (HB-EGF) is one of the EGF family to be expressed at the time of implantation in the mouse uterus. Although HB-EGF has been shown to stimulate the development of embryo and uterus in the mouse, its correlation between cell adhesion molecules remains undefined. Integrin $\alpha$$_{ν}$$\beta$$_3$, one of the cell adhesion molecules, is an important mediator of cell-substratum and cell-cell adhesion in implantation. In the present studies, we investigated the effects of HB-EGF on the embryonic development, initiation of implantation and expression of integrin $\alpha$$_{ν}$$\beta$$_3$ in in vitro culture, blocking of HB-EGF, RT-PCR and immunofluores cence analysis. The results showed that HB-EGF significantly improved the developmental rate of hatched embryos (24.1%, p<0.01) and outgrowth embryos (42.5%, p<0.01). On the other hand, this growth factor showed no offset before the hatching embryonic stage. Analysis of RT-PCR showed that HB-EGF upregulated the expression level of integrina $\alpha$$_{ν}$$\beta$$_3$ subunit genes on the preimplantation embryo and outgrowth of blastocyst (120hr and 144hr after hCG injection). Immunofluorescence analysis showed that the integrin $\alpha$$_{ν}$$\beta$$_3$ subunits localized at the pericellular borders and cell-cell contact areas. Increase in fluorescence intensity was observed in the HB-EGF treated embryos. Intrauterine injection of an anti-HB-EGF antiserum at day 3 significantly decreased the number of implantation sites (14.4, p<0.01) and significantly increased the number of recovered embryos(6.4, p<0.05) at day 5. From these results, it imply that HB-EGF improve the embryo development and accelerated the expression of integrin $\alpha$$_{ν}$$\beta$$_3$ in the preimplantation mouse embryos.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.687-694
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• 2008

Background: Although aortic valve sclerosis causes no significant hemodynamic alterations, it is associated with an increased risk of cardiovascular death and myocardial infarction. However, the role of ${\beta}_3$ integrin in aortic valve sclerosis remains unclear. Material and Method: Twenty male New Zealand rabbits were divided into two groups. Group 1 rabbits (n=10) received a normal chow diet, while group 2 (n=10) rabbits received a diet containing 1% cholesterol for 12 weeks. After the rabbits were euthanized, their aortic valves and ascending aortas were excised for analysis. Result: Total serum cholesterol ($2,148.3{\pm}1,012.5\;mg/dL$ versus $53.7{\pm}31.8\;mg/dL$, p<0.05), triglyceride ($240.4{\pm}218.3\;mg/dL$ versus $31.6{\pm}6.4\;mg/dL$, p<0.05), and low density lipoprotein (LDL)-cholesterol($2,065.3{\pm}960.9\;mg/dL$ versus $29.1{\pm}30.9\;mg/dL$, p<0.05) levels were significantly higher in the cholesterol diet group compared with the normal diet group. Myofibroblasts and macrophages were more highly expressed in the aortic valve leaflets of rabbits in the cholesterol diet group than of those in the normal diet group. A real-time polymerase chain reaction revealed decreased ${\beta}_3$ integrin mRNA levels in the hypercholesterolemic aortic valves and aortas. Conclusion: The present study shows that hypercholesterolemia induces aortic valve sclerosis. These findings suggest that alterations in ${\beta}_3$ integrin may playa role in the development of aortic valve sclerosis.

• Journal of Integrative Natural Science
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• v.6 no.4
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• pp.234-243
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• 2013

N-terminal kinase-like (NTKL) protein was initially identified as a protein binding to protein kinase B (PKB, also known as Akt). Though NTKL-BP1 (NTKL-binding protein 1) has been identified as an NTKL binding protein, its functions related to binding have not yet been elucidated. Here, a new alternative spliced variant of NTKL and its association with integrin ${\beta}1$ is described, in addition to the kinase activity of NTKL and its substrate candidates. Although the phosphorylation of the candidates must be further confirmed using other experimental methods, the observation that NTKL can phosphorylate ROCK1, DYRK3, and MST1 indicates that NTKL may act as a signaling protein to regulate actin assembly, cell migration, cell growth, and to facilitate differentiation and development in an integrin-associated manner.

• Animal cells and systems
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• v.8 no.1
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• pp.27-32
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• 2004

Endothellial cells are subjected to hemodynamic shear stress, the dragging force generated by blood flow. Shear stress regulates endothelial cell shape, structure, and function, including gene expression. Since endothelial cells must be anchored to their extracellular matrices(ECM) for their survival and growth, we hypothesized that ECMs are crucial for shear-dependent activation of extracellular signalactivated regulated kinase(ERK) that is important for cell proliferation. Shear stress-dependent activation of ERK was observed in cells plated on two different matrices, fibronectin and vitronectin(the two most physiologically relevant ECM in endothelial cells). We then treated bovine aortic endothelial cells(BAECs) with Arg-Gly-Asp(RGD) peptides that block the functional activation of integrin binding to fibronectin and vitronectin, and a nonfunctional peptide as a control. Treatment of cells with the RGD peptides, but not the control peptide, significantly inhibited ERK activity in a concentration-dependent manner. This supports the idea that integrin adhesion to the ligands, fibronectin and vitronectin, mediates shear stress-dependent activation of ERK. Subsequently, whereas antagonists of vitronectin(LM 609, an antibody for integrin ${\alpha}_{\gamma}$/${\beta}_3$ and XT 199, an antagonist specific for integrin ${\alpha}_{\gamma}$/${\beta}_3$) did not have any effect on shear-dependent activation of ERK, antagonists of fibronectin(a neutralizing antibody for integrin ${\alpha}_5$/${\beta}_1$or ${\alpha}_4$${\beta}_1$ and SM256) had an inhibitory effect. These results clearly demonstrate that mechanoactivation of ERK requires anchoring of endothelial cells to fibronectin through integrins.

• BMB Reports
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• v.50 no.8
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• pp.429-434
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• 2017

Endometriosis is the abnormal growth of endometrial cells outside the uterus, causing pelvic pain and infertility. Furthermore, adhesion of endometrial tissue fragments to pelvic mesothelium is required for the initial step of endometriosis formation outside uterus. $TGF-{\beta}1$ and adhesion molecules importantly function for adhesion of endometrial tissue fragments to mesothelium outside uterus. However, the function of $TGF-{\beta}1$ on the regulation of adhesion molecule expression for adhesion of endometrial tissue fragments to mesothelium has not been fully elucidated. Interestingly, transforming growth factor ${\beta}1$ ($TGF-{\beta}1$) expression was higher in endometriotic epithelial cells than in normal endometrial cells. The adhesion efficiency of endometriotic epithelial cells to mesothelial cells was also higher than that of normal endometrial cells. Moreover, $TGF-{\beta}1$ directly induced the adhesion of endometrial cells to mesothelial cells through the regulation of integrin of ${\alpha}V$, ${\alpha}6$, ${\beta}1$, and ${\beta}4$ via the activation of the $TGF-{\beta}1/TGF-{\beta}RI/Smad2$ signaling pathway. Conversely, the adhesion of $TGF-{\beta}1-stimulated$ endometrial cells to mesothelial cells was clearly reduced following treatment with neutralizing antibodies against specific $TGF-{\beta}1-mediated$ integrins ${\alpha}V$, ${\beta}1$, and ${\beta}4$ on the endometrial cell membrane. Taken together, these results suggest that $TGF-{\beta}1$ may act to promote the initiation of endometriosis by enhancing integrin-mediated cell-cell adhesion.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.38-38
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• 2001

Spermatogonial stem cells은 sperrnatogenesis에서 중요한 역할을 하며, 곡세정관의 기저막에 위치하고 있는 것으로 알려져 있다. 그러나, 그 동안 이 세포에 특이하게 발현되는 marker가 거의 알려져 있지 않아 spermatogonial stem cell의 연구에 많은 어려움을 가져왔다. 최근 일반적인 stem cell이 갖는 특성 중, 기저막과 상호작용을 하는 surface protein으로 integrin이 존재한다는 사실을 이용하여, anti-$\alpha$$_{6}$/ 또는 anti-$\beta$$_1$ integrin항체로 germ cell을 선발하여 정소에 이식한 결과, 높은 효율로 이식세포유래의 정자발생이 가능하다는 결과가 보고되었다 (Shinohara et al., 1999). 한편, 항암제의 일종인 busulfan을 마우스에 투여(40mg/kg)한 후 4-5주가 경과하면 세정관의 기저막에 위치하는 spermatogonia를 제외하고 대부분의 생식세포는 소멸한다 본 실험의 목적은 이러한 사실들을 이용하여 spermatogonial stem cell의 특성을 밝히고, 이 생식세포를 보다 간편하고 손쉽게 선발할 수 있는 시스템을 확립하는데 있다. Busulfan처리 후 5주가 경과된 마우스와 정상적인 13주령의 마우스 testis로부터 세포를 분리한 후 FITC-conjugated anti-IgG를 이용한 면역형광법으로 측정.분석한 결과, 형광표식된 세포비율이 대조군과 비교하여 busulfan을 처리한 경우에서 유의적인 증가를 보였다.(17$\pm$3.8%. 0.7$\pm$0.3% busulfan vs control). 또한, IgG와 결합한 단백질이 존재하는 이들 세포들은 곡세정관의 기저막을 따라 위치하며, 단백질과 복합체를 형성한 IgG는 anti-Ig $G_{2a}$와 반응하지 않는다는 사실을 관찰했다. 이러한 IgG 복합체를 형성한 세포들의 특성을 이용하여, IgG와 반응을 하지 않는 것으로 확인된 이차 항체인 an1i-Ig $G_{2}$와 일차 항체인 anti-$\alpha$$_{6}$ 또는 anti-$\beta$$_1$ integrin항체를 이용하여 측정.분석하였다. Busulfan을 처리한 마우스 정소에서 분리한 세포를 다시 laminin으로 코팅된 dish에서 선발.회수해서, anti-lgG, anti-$\alpha$$_{6}$ 또는 anti-$\beta$$_1$ integrin항체로 각각 표식된 세포비율을 비교하였다. Laminin으로부터 선발.회수한 세포에서는 IgG복합체가 $\alpha$$_{6}$ 또 는 $\beta$$_1$integrin과 거의 같은 수준에서 높은 비율로 표식되었다. 결론적으로, busulfan에 의해 유도된 IgG와 결합가능한 단백질은 $\alpha$$_{6}$나 $\beta$$_1$ integrin과 마찬가지로 immunoglobulin G를 이용하여 spermatogonial stem cell의 선발을 가능하게 했다. 따라서, busulfan처리시 IgG는 미분화된 정조세포의 선발을 위한 하나의 marker로서 사용가능함을 시사한다.다.