IL-1 beta 抑制臍靜脈內皮細胞遷移之分子機轉

The molecular mechanisms underlying IL-1 beta-induced human umbilical vein endothelial cells migration inhibition

許睿奇(Jui-Chi Hsu)

指導教授 ： 李文森

臺北醫學大學/醫學院/醫學科學研究所/碩士(2009年)

https://doi.org/10.6831/TMU.2009.00123

摘要

本篇論文的主旨是在探討IL-1β抑制血管內皮細胞遷移之分子機轉。在過去的文獻中指出，血管增生現象在許多生理及病理現象中都扮演相當重要的角色。例如當腫瘤形成時，為了從活體中得到大量養分以及進行物質交換，腫瘤會釋放出血管增生因子與周邊血管上的接受器結合，促使血管內皮細胞向腫瘤的方向進行遷移，並且逐漸形成新生之血管。而針對控制癌症的血管增生現象，成為目前治療癌症很重要的方向。由於血管增生的過程，伴隨著許多生長因子及細胞激素的釋放，如VEGF及IL-1β。因此本實驗室利用人類臍帶靜脈內皮細胞(human umbilical vein endothelial cell, HUVEC)來探討IL-1β對血管增生的影響。我們首先給予IL-1β處理二十四小時後，利用西方點墨法以及反轉錄-聚合酶連鎖反應實驗證實Thy-1在蛋白質或是在RNA層級都會有大量表現。進一步進行了創傷修復實驗，給予IL-1β處理二十四小時後，遷移之內皮細胞數目有明顯的減少現象。而本實驗室先前在細胞實驗中也發現在Thy-1過度表現時，內皮細胞遷移受到了明顯的抑制。所以推測IL-1β可能是藉由增加Thy-1來抑制細胞遷移。接著我們針對訊息傳遞相關蛋白質進行西方點墨法實驗，發現到PKC family之PKC δ有明顯的增加。PKCδ蛋白質會因為其在細胞內之表現聚集位置不同而產生不同的效應，我們發現到分布於細胞膜的PKCδ，其表現量在給與IL-1β的組別中，有明顯上升的情況。此外，我們藉由Gö6976以及Röttlerin等PKC抑制劑的作用，利用西方點墨法和微血管形成實驗證實，IL-1β所造成的內皮細胞遷移及管腔形成的抑制現象，主要是藉由PKCδ-mediated pathway所造成。我們同時使用RNA干擾的技術將內皮細胞中的Thy-1 mRNA knockdown後，進行西方點墨法和細胞遷移的實驗，結果發現由IL-1β誘導增加之Thy-1被knockdown後，IL-1β抑制細胞遷移的現象明顯的回復，證明Thy-1在抑制細胞遷移扮演一重要角色。綜合以上實驗結果我們可以發現，IL-1β會藉由PKC δ-mediated pathway增加Thy-1 蛋白質的表現，並且達到抑制細胞遷移的現象，也藉由未知的分子路徑抑制血管內皮細胞之血管構造形成。

關鍵字

血管增生 ； 細胞遷移

並列摘要

It has been recognized that angiogenesis is required in many physiological and pathological conditions. For instance, in the development of tumor, in order to get more nutrients, tumor cells promote vessel formation through the expression of angiogenic molecules in the microenvironment. The understanding that the growth of tumors depends on the acquisition of a blood supply has led to the development of new therapies strategy for cancer based on inhibition of angiogenesis. It has been known that several growth factors and cytokines were released during angiogenesis, such as VEGF and IL-1 beta. The aim of this thesis study is to examine the molecular mechanisms underlying IL-1 beta-induced human umbilical vein endothelial cells migration inhibition. To gain this purpose, we treated HUVEC with IL-1 beta. Our data demonstrated that after 24 hours IL-1 beta treatment up-regulated the expression of Thy-1 mRNA and protein, activated PKC delta and inhibited HUVEC migration and capillary-like tube formation. Moreover, we found that treatment of HUVEC with PKC delta inhibitor, Röttlerin, dramatically reversed the IL-1 beta-induced inhibition of cell migration and tube formation. Knockdown Thy-1 protein by transfection of Thy-1 siRNA into HUVEC partially reversed the IL-1 beta-induced inhibition of cell migration. Taken together, our data suggest that IL-1 betanmight induce migration inhibition in HUVEC though up-regulation of Thy-1 molecule via a PCK delta-dependent pathway.

並列關鍵字

IL-1 beta ； angiogenesis ； PKC ； migration

參考文獻

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