DC 欄位 | 值 | 語言 |
dc.contributor | 陳瑞華 | zh-TW |
dc.contributor | 臺灣大學:分子醫學研究所 | zh-TW |
dc.contributor.author | 沈哲宏 | zh-TW |
dc.contributor.author | Shen, Che-Hung | en |
dc.creator | 沈哲宏 | zh-TW |
dc.creator | Shen, Che-Hung | en |
dc.date | 2008 | en |
dc.date.accessioned | 2010-05-04T06:49:14Z | - |
dc.date.accessioned | 2018-07-09T01:10:27Z | - |
dc.date.available | 2010-05-04T06:49:14Z | - |
dc.date.available | 2018-07-09T01:10:27Z | - |
dc.date.issued | 2008 | - |
dc.identifier.other | U0001-0108200813521200 | en |
dc.identifier.uri | http://ntur.lib.ntu.edu.tw//handle/246246/178638 | - |
dc.description.abstract | 乳癌激酶是一種非受體型酪胺酸激酶與Src有高度相似性,其蛋白質結構由典型的SH3區塊、SH2區塊以及酪胺酸激酶區所組成。乳癌激酶已於乳癌、黑色素細胞瘤以及大腸癌等癌症中被報導具有高度表現性,也被認為在細胞癌化機轉(oncogenesis)中扮演重要角色。但是目前對於乳癌激酶的活性調控及其所參與的信息傳導路徑,乃至於生物功能的了解均十分有限。因此,探查乳癌激酶所作用的受質與其所參與的信息傳導途徑,能進一步揭開乳癌激酶的生物功能及致癌機轉。在此,我們找到了一新的乳癌激酶受質-p190RhoGAP-A (p190)。乳癌激酶透過磷酸化p190促使p190與p120RasGAP (p120)結合,此蛋白質複合體具有能抑制Rho及活化Ras的能力。乳癌激酶也藉由磷酸化p190抑制Rho及活化Ras,並且刺激細胞移動、促進細胞的侵入行為以及導致細胞增生。此外我們也發現若利用干擾蛋白破壞p190與p120之間的結合,將弱化乳癌激酶調控Rho及Ras的能力,也減弱其對細胞行為及生長的影響,並進一步降低乳癌激酶的致癌性(tumorigenicity)。因此p190在乳癌激酶所作用的信息傳導路徑及於生物功能上扮演重要功能。 | zh-TW |
dc.description.abstract | Breast tumor kinase (Brk), a Src-like nonreceptor tyrosine kinase, is overexpressed in breast cancer and several other cancer types. Our previous study indicates that Brk promotes cell migration and tumor invasion by phosphorylating the focal adhesion protein paxillin. Here, we report the identification of p190RhoGAP-A (p190) as a Brk substrate. Brk phosphorylates p190 at the Y1105 residue both in vitro and in vivo, thereby promoting the association of p190 with p120RasGAP (p120). As a consequence, Brk stimulates p190 and attenuates p120 functions, leading to RhoA inactivation and Ras activation, respectively. In carcinoma cells expressing high levels of Brk, endogenous Brk functions as a key contributor to EGF-induced p190 tyrosine phosphorylation. We present evidence showing that p190 phosphorylation plays essential roles in both migratory and proliferative effects of Brk. Furthermore, disruption of p190 phosphorylation-induced p190/p120 complex in breast cancer cells abolishes not only the abilities of Brk to regulate RhoA and Ras, but also the stimulatory effects of Brk on proliferation, migration, invasion, transformation and tumorigenicity. Together, our findings reveal a previously unknown function of Brk in regulating both RhoA and Ras by phosphorylating p190, and provide evidence for the crucial roles of this Brk-elicited signaling pathway in promoting breast malignancy. | en |
dc.description.tableofcontents | Table of Contents……………………………………………………..02文摘要……………………………………………………………….04bstract………………………………………………………………...05iterature Review…………………………………………………..…06. Mechanisms that control tumor progression……………………………….07. The roles of protein tyrosine kinases in cancers…………………………..08.1 PTK classification ……………………………………………………….08.2 The mechanisms of PTK activity regulation…………………………..10.3 PTK activation in cancers……………………………………………….11. Overview of Brk: expression, regulation and functions……………………13.1 Brk sequence features and domain structure…………………………13.2 Brk expression in normal and cancer tissues…………………………15.3 Brk-mediated signaling pathways and its biological functions………16. Ras and Rho small GTPases………………………………………………...19.1 Overview of small GTPases…………………………………………….19.1.1 Discovery, classification, and structure of small GTPases……19.1.2 The regulation of GTPases activity of small G proteins……….21.2 Ras GTPases…………………………………………………………….23.2.1 Ras family…………………………………………………………..23.2.2 Effectors and functions of Ras……………………………………24.2.3 Ras and cancer…………………………………………………….26.2.3.1 Ras in cell transformation………………………………...27.2.3.2 Ras in tumor cell invasion and metastasis……………...28.2.3.3 Ras in angiogenesis………………………………………29.3 Rho GTPases……………………………………………………………30.3.1 Rho family………………………………………………………….30.3.2 Effectors and functions of Rho GTPases……………………….32.3.3 Rho GTPases and cancer………………………………………..35.3.3.1 Altered Rho GTPases signaling in cancers…………….35lterations of Rho proteins in cancers……………………35lterations of Rho regulators in cancers…………………36lterations of Rho effectors in cancers…………………..37.3.3.2 Rho GTPases in tumorigenesis and tumor metastasis.38 . The cross-talk between Rho and Ras………………………………………41.1 p120RasGAP…………………………………………………………….41.2 p190RhoGAP…………………………………………………………….42.3 The cross-talk between RhoA and Ras………………………………..43xperimental rationale………………………………………………..45rk phosphorylates p190RhoGAP to regulate Rho and Ras and to promote breast carcinoma growth, migration and invasion……..46ntroduction………………………………………………………………………..47aterials and methods…………………………………………………………..51ell culture, transfection and retroviral infection…………………………...51lasmid constructions…………………………………………………………51NA interference………………………………………………………………52ntibodies………………………………………………………………………52ssay for GTP-bound Rho, Rac and Ras…………………………………..53igration and invasion assays……………………………………………….53mmunoprecipitations and GST fusion proteins…………………………….53n vitro kinase assay……………………………………………………………54mmunofluorescence analysis………………………………………………...54oft agar colony formation assay…………………………………………….54umorigenesis in mice…………………………………………………………55esults…………………………………………………………………………….56rk inhibits stress fiber formation and promotes cell spreading…………..56rk interacts with p190 and phosphorylates p190 at Y1105………………57rk stimulates the functions of p190 to inactivate Rho and to active Ras.59rk mediates EGF-induced p190 tyrosine phosphorylation……………….60190 is critical for the migratory and mitogenic effects of Brk……………..62isruption of the p190/p120 complex blocks the tumor promoting activities of Brk in breast cancer cells…………………………………………………64iscussion…………………………………………………………………………66eference……………………………………………………………..71igure………………………………………………………………….88 | en |
dc.format | application/pdf | en |
dc.format.extent | 1621934 bytes | - |
dc.format.mimetype | application/pdf | - |
dc.language | en | en |
dc.language.iso | en_US | - |
dc.subject | 乳癌激酶細胞增生 | zh-TW |
dc.subject | 細胞移動 | zh-TW |
dc.subject | Brk | en |
dc.subject | Cell proliferation | en |
dc.subject | Cell migration | en |
dc.subject.classification | [SDGs]SDG3 | - |
dc.title | 乳癌激酶促進癌細胞生長及移動之機制研究 | zh-TW |
dc.title | The Mechanisms of Breast Tumor Kinase in Promoting Tumor Cell Growth and Migration | en |
dc.identifier.uri.fulltext | http://ntur.lib.ntu.edu.tw/bitstream/246246/178638/1/ntu-97-D92448004-1.pdf | - |
item.languageiso639-1 | en_US | - |
item.grantfulltext | open | - |
item.fulltext | with fulltext | - |
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