Full metadata record
DC Field | Value | Language |
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dc.contributor.advisor | 오억수 | - |
dc.contributor.author | 김보민 | - |
dc.creator | 김보민 | - |
dc.date.accessioned | 2016-08-26T04:08:10Z | - |
dc.date.available | 2016-08-26T04:08:10Z | - |
dc.date.issued | 2016 | - |
dc.identifier.other | OAK-000000120730 | - |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/214228 | - |
dc.identifier.uri | http://dcollection.ewha.ac.kr/jsp/common/DcLoOrgPer.jsp?sItemId=000000120730 | - |
dc.description.abstract | Epithelial-mesenchymal transition (EMT) is a physiological process that epithelial cells acquire the mesenchymal phenotypes including migratory and invasive characteristics. During EMT, epithelial cells lose key phenotypic markers including E-cadherin and cytokeratin 18, and acquire mesenchymal markers, such as N-cadherin and vimentin. Although loss of cytokeratin 18 is known to be a hallmark of EMT, its regulatory role on EMT is not yet fully understood. When MCF10A cells were treated with transforming growth factor-beta1 (TGF-β1), a convenient way to induce EMT, considerable morphological changes (e.g. loss of cell-cell contact) were occurred, but E-cadherin levels were remained unchanged at 24 h after TGF-β1 treatment. In contrast, reduction of intracellular levels of cytokeratin 18 was observed ahead of those of E-cadherin, suggesting an active role of cytokeratin 18 at an early stage of EMT. Consistently, knockdown of cytokeratin 18 using target-specific siRNA resulted in delayed TGF-β1-mediated EMT including E-cadherin downregulation. Furthermore, phosphorylation and nuclear localization of smad2/3, and expression of snail and slug which inhibit E-cadherin expression in epithelial cells, were much reduced in siRNA-mediated cytokeratin 18 knockdown cells in an early response to TGF-β1. Taken together, these results suggest that cytokeratin 18 is necessary for initiation of TGF-β1-induced EMT by regulating smad2/3-mediated expression regulation of snail and slug. ;Epithelial-mesenchymal transition (EMT)는 상피세포가 중간엽세포의 운동성을 획득하게 되는 생리학적 현상을 말한다. EMT가 일어나는 동안, 상피세포는 상피세포의 마커인 E-cadherin과 cytokeratin 18의 발현은 감소하고, 중간엽세포의 마커인 N-cadherin과 vimentin의 발현은 증가한다. Cytokeratin 18의 감소는 EMT의 전형적인 특징으로 알려져 있으나, EMT 조절과 관련된 역할은 자세히 알려진 바가 없다. 유방상피세포주인 MCF10A에 대표적인 EMT 유도물질인 transforming growth factor(TGF-β1)를 처리하였을 때, 세포간 간격이 멀어지는 형태학적 변화가 유도되었으나, 24시간 동안의 TGF-β1 처리로는 E-cadherin의 발현은 변하지 않았다. 반면, 세포 내 cytokeratin 18의 발현 감소는 E-cahderin의 발현 감소보다 선행되는 것이 관찰되었으며, 이를 통해 EMT 초기 단계에서 cytokeratin 18의 능동적인 역할이 제시되었다. 일관하여, target 특이적인 siRNA를 이용한 cytokeratin 18 knockdown은 E-cadherin의 감소 등을 포함하는 TGF-β1에 의해 유도되는 EMT를 지연시키는 결과를 나타냈다. 뿐만 아니라, TGF-β1의 초기반응에서 cytokeratin 18 knockdown에 의해 smad2/3의 인산화, 핵으로의 translocation이 지연되었고, E-cadherin의 발현을 억제하는 snail과 slug의 발현도 억제되었다. 이러한 결과는 cytokeratin 18이 smad2/3을 매개로 하는 snail과 slug의 발현을 조절하여 TGF-β1에 의해 유도되는 EMT의 개시에 필수적임을 제시한다. | - |
dc.description.tableofcontents | I. INTRODUCTION 1 II. MATERIALS AND METHODS 5 1. Materials and antibodies 5 2. Cell Culture and transfection 5 3. RNA extraction and reverse transcription polymerase chain reaction (RT-PCR) 6 4. Immunoblotting 7 5. Knockdown of cytokeratin 18 using siRNA 8 6. Immunofluorescence analysis 8 7. Transwel migration assay 9 8. Nuclear extraction assay 9 9. Statistical analysis 10 III. RESULTS 11 1. TGF-β1 downregulates cytokeratin 18 in early time periods without E-cadherin regulation in breast epithelial cells 11 2. Reduction of cytokeratin 18 expression does not contribute to E-cadherin expression in breast epithelial cell 16 3. Loss of cytokeratin 18 inhibits TGF-β1-induced E-cadherin downregulation 19 4. Cytokeratin 18 regulates TGF-β1-induced upregulation of snail and slug 23 5. Cytokeratin 18 regulates snail and slug expression via smad2/3 signaling pathway 28 IV. DISCUSSION 32 V. REFERENCES 39 국문 초록 46 | - |
dc.format | application/pdf | - |
dc.format.extent | 1254567 bytes | - |
dc.language | eng | - |
dc.publisher | 이화여자대학교 대학원 | - |
dc.subject.ddc | 600 | - |
dc.title | Cytokeratin 18 is necessary for initiation of TGF-β1-induced Epithelial Mesenchymal Transition in Breast Epithelial Cells | - |
dc.type | Master's Thesis | - |
dc.format.page | v, 47 p. | - |
dc.contributor.examiner | 이수영 | - |
dc.contributor.examiner | 이승택 | - |
dc.contributor.examiner | 오억수 | - |
dc.identifier.thesisdegree | Master | - |
dc.identifier.major | 대학원 생명과학과 | - |
dc.date.awarded | 2016. 2 | - |