• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1039-1045
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• 2007

Glioblastoma multiforme (GBM) is the most frequently occurring brain cancer. Although the existence of cancer stem cells (CSCs) in GBM has been established, there is little evidence to explain the link between CSCs and chemoresistance. In this study, we investigated that only a few cells of A172 and established GBM2 survived after 1,3-bis(2chloroethyl)-1-nitrosourea (BiCNU) exposures and these sur-vived cells resist the subsequent BiCNU treatment. In addition, these BiCNU-resistant small pop-ulations derived from GBM cells increased the phosphorylations of Erk and Akt and highly expressed CD133 stem cell surface marker. Furthermore, we observed that the BiCNU-resistant cancer cells de-rived from GBM have grown tumors when transplanted into severe combined immuno-deficient (SCID) mouse brain. These results demonstrate that BiCNU-resistant subpopulation cells derived from GBM have cancer stem-like cell properties. Therefore, it may provide provide further evidence that CSCs in GBM have chemotherapeutic drug resistance.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.61-65
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• 2018

Our experiment studied that grafted stem cells reduced behavioral deficiency in rodent animal models of clip compressive surgery inducing spinal cord infarction. Our research proved the effect of embryonic stem cells to the spinal cord infarction caused by compressing T9-10 with an aneurysm clip, focusing the application of grafted stem cells for reduction of infarction and regeneration of spinal cord nervous injury. Therefore, our research suggests manifest results that implantation of mouse embryonic stem cell could show behavioral improvement after severe spinal cord damage. Therefore, mouse embryonic stem cell (mESC) could be useful application for the method in neurological injury. Conclusively, stem cell implant therapy may enhance the effectiveness of stem cell implant for central nervous system injury.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.5-12
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• 2008

Objectives : Showing that Bong-Han corpuscles(BHC) are suppliers of the stem cells in adulthood, and the Bong-Han ducts(BHD) are transportation routes of stem cells. Methods : BHC and BHD were obtained from the internal organ-surfaces of rats. The sliced BHC and BHD were immunostained with various stem cell markers. Extracellular matrices were also analyzed by immunohistochemistry. Result : The presence of mesenchymal stem cells was confirmed by the expression of Integrin beta 1, Collagen type 1 and Fibronectin. But CD54 was not expressed. The hematopoietic stem cell marker, Thy 1 was strongly expressed. BHDs showed Collagen type 1, Fibronectin, and vWF expression. Conclusion : Both hematopoietic and mesenchymal stem cell markers were expressed strongly in BHC similarly as in bone marrow. An endothelial cell marker(vWF) demonstrated the possibility of the stem cell transportation routes of BHD.

• Development and Reproduction
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• v.14 no.2
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• pp.43-50
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• 2010

Recently induced pluripotent stem (iPS) cells are derived from somatic cells by ectopic expression of several transcription factors (reprogramming factors) using technology of somatic cell reprogramming. iPS cells are able to selfrenew and differentiate into all type of cells in the body similarly to embryonic stem cells. Because iPS cells have advantages that can avoid immune rejection after transplantation and ethical issues unlike embryonic stem cells, research on iPS has made significant progress since the first report by Yamanaka in 2006. Nevertheless of many advantages of iPS, safer methods to introduce reprogramming factors into somatic cells must be developed due to safety concerns regarding viral vectors, and safer reprogramming factors to substitute the oncogenes should be evaluated for clinical application of iPS. Here we discuss the recent progress in reprogramming factors in embryonic stem cells, oocytes, and embryos, and discuss further research for finding new, more reliable and safer reprogramming factors.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.271-271
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• 2004

본 실험은 TGF-a를 처리하여 분화가 유도된 인간배아 줄기세포를 파킨슨 동물모델에 이식하여 숙주세포에서의 생존 및 이식효과를 검토하고자 실시하였다. TGF-a로 분화된 세포의 이식효과를 판정하고자 배양시 TGF-a처리군과 처리하지 않은 군으로 나누어 분화를 유도한 인간배아 줄기세포를 hoechst33342로 표지 하여 병변 유발과 동일한 방법으로 동측 선조체내에 4×10⁴개/2ul가 되도록 이식하고(이식 위치: AP 0.7, ML 2.0, DV3.4) 이식 후 2, 4주에서 행동학적 변화를 관찰하고 4주에 동물을 희생시켜 4% PFA를 이용하여 뇌 조직을 고정하고 뇌 조직은 40㎛ 두께로 동결 절편을 만들어 면역조직화학염색을 시행하여 신경세포로의 분화 및 TH 발현 여부를 관찰하였고 분화의 표지물질로 nestin, NF200, GFAP, TH를 사용하여 형태학적 변화를 관찰하였다. (중략)

• Journal of Science and Technology Studies
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• v.15 no.1
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• pp.181-214
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• 2015

This study analyzed the characteristics of the politics of technoscience and governance in South Korea, taking advantage of the policy changes on the stem cell research after Hwang's affair. In spite of generally accepted conventional wisdom that stem cell research had been suffering 'crisis' after the Hwang's affair, South Korea succeeded in developing the first and the largest stem cell product in the world. However, considering the fact that the stem cell research capabilities and technological competitiveness of Korea have been assessed as relatively low compared to the development performance, there is a need to extrapolate how such result could be achieved. To answer these questions, we analyzed changes in the R&D expenditure before and after the scandal and verified the 'crisis of stem cell research' following the reduction of financial support from government. From the analysis of literature on the policy reports and news, we described the process of discourse changes in policy and analyzed the characteristics of the politics of technoscience and governance of stem cell research. This study emphasized that the government R&D and regulation policy play the key roles in the development of stem cell research rather than in the technological competitiveness in South Korea. Furthermore, this study argued that democratic governance still does not work under the policy conditions that technocratic decision-making of stem cell research fails to learn from the Hwang's affairs.

• Journal of Life Science
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• v.25 no.6
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• pp.724-731
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• 2015

Mesenchymal stem cells (MSCs) are characterized by their multipotency capacity, which allows them to differentiate into diverse cell types (bone, cartilage, fat, tendon, and neuron-like cells) and secrete a variety of trophic factors (ANG, FGF-2, HGF, IGF-1, PIGF, SDF-1α, TGF-β, and VEGF). MSCs can be easily isolated from human bone-marrow, fat, and umbilical-cord tissues. These features indicate that MSCs might be of use in stem-cell therapy. However, MSCs undergo cellular senescence during long-term expansion, and this is accompanied by functional declines in stem-cell potency. In the human body, because of their senescence and declines in their microenvironmental niches stem cells fail to maintain tissue homeostasis, and as a result, senescent cells accumulate in tissues. This can lead to age-related diseases, including degenerative disorders and cancers. Recent studies suggest that the number of histone modifications to stem cells’ genomes and aberrant alterations to their DNA methylation increase as stem cells progress into senescence. These epigenetic alterations have been partly reversed with treatments in which DNA methyltransferase (DNMT) inhibitors or histone deacetylase (HDAC) inhibitors are introduced into replicative senescent-MSCs. This review focuses on epigenetic alteration in replicative senescent-MSCs and explains how epigenetic modifications are widely associated with stem-cell senescences such as differentiation, proliferation, migration, calcium signaling, and apoptosis.

• The Science & Technology
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• v.35 no.4 s.395
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• pp.20-21
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• 2002

포천중문의대 차병원 세포유전자연구소의 연구팀은 국내 처음으로 쥐의 배아 줄기세포를 살아있는 쥐의 뇌에 이식하여 손상된 뇌신경의 기능을 회복시킬 수 있는 뇌세포를 만드는데 성공했다. 이 연구팀은 쥐실험과 같은 연구과정을 사람에게 적용하는 실험을 하기 위해 오는 5월 '줄기세포치료이식센터'를 완공할 계획이다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.809-815
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• 2016

In this paper, the electrical values of resistance, current, and voltage condition of reactivity is analyzed by applying the direct current (DC) voltage in medium for stem cell regeneration treatment. The voltage response by medium is related to electrical stimulation in the process of induction of differentiation for stem cell and the differentiation condition can be checked depending on the response of voltage condition. If the voltage level is lower in reacting response of a medium, the stem cell stimulation condition is stable, and if the voltage changing level is higher, the stem cell stimulation condition is unstable and a considerable loss will be resulted in the differentiation process. In this research, the optimization of electrical stimulation condition is expected for possible stem cell regeneration treatment.

• Journal of Life Science
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• v.32 no.6
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• pp.468-475
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• 2022

The functional distinction between stem and progenitor cells is well established in several tissues, particularly in the blood. There, hematopoietic stem cells preserve their self-renewal potential and reconstitution ability in the bone marrow niche. Bone marrow represents a unique setting in which to examine how stroma influences tissue function. It was the setting in which the experimental definition of a niche was first provided in mammalian stem cell biology and where clear evidence for non-cell-autonomous oncogenesis was first defined. The relationship between bone and blood is ancient as all animals since the divergence of fish that have bones and blood, make blood in their bones. This long coevolution engendered complex interrelationships, including the first proposed and first experimentally defined niche for stem cells in mammals. Multiple bone marrow stromal cell types serve as regulators of hematopoiesis, and the dysfunction of some causes myelodysplasia and leukemia. However, no comprehensive atlas of stromal subpopulations exists. Therefore, we think these data point to something of importance, such as how the needs and challenges of the organism become translated down to distinct cell types that critically govern specific functions within tissues and do so at the level of a single molecule. We think this will be of broad interest to those focusing on systems biology and the physiology of organisms, particularly those seeking a molecular basis for understanding cell and tissue behavior. We summarized the current and emerging concepts of hematopoietic stem cells and bone marrow niche.