出版年:

2002

研究生:

吳明杰

研究生(英文姓名):

Ming-Chiech Wu

論文名稱:

子宮頸癌細胞膨脹活化STAT3蛋白及相關訊息傳遞路徑之研究

英文論文名稱:

Study on cell swelling activation of STAT3 protein and related signal transaduction pathways in cervical cancer SiHa cells.

指導教授:

周振陽 ; 劉校生

指導教授(英文姓名):

Cheng-Yang Chou ; Hsiao-Sheng Liu

學位類別:

碩士

校院名稱:

國立成功大學　

系所名稱:

微生物暨免疫學研究所

學號:

s46891071

學年度:

90

語文別:

英文

論文頁數:

63

關鍵詞:

細胞膨脹 ; 訊息傳導

英文關鍵詞:

cell swelling ; siganl transduction ;
STAT3 ; SiHa

被引用次數:

0

[ 摘要 ]

細胞在進行有絲分裂或受到滲透壓的挑戰，會透過不同的機制正確調節它們的細胞容積。細胞容積的恆定不只是指容積的不變，而且還包含調控細胞功能。調節的容積降低反應是一種經過低張刺激後，細胞容積適應的一種過程。STAT3是一種轉錄因子，活化後會移行到核內去和反應性要素做結合。本實驗，以子宮頸癌細胞，SiHa的整個細胞裂解物或核蛋白來研究STAT3的活化。我們以西方墨點法發現，在未使用Sodium vanadate 〈是一種酪氨酸去磷酸脢的抑制劑〉情況下，低張刺激會造成STAT3酪氨酸位置有磷酸化的現象，而且持續五個小時。免疫螢光染色研究進一步顯示低張可以使STAT3移行至核內。STAT3酪氨酸磷酸化在低張和sodium vanadate 的共同使用下更加提升。 此外，低張也可以引起STAT3絲氨酸磷酸化，和ErK1/2磷酸化。這些現象以西方墨點法使用核萃取物和MEK抑制劑PD98059來確信。而且STAT3絲氨酸的磷酸化可被PKC刺激劑PMA所增強，被PKC抑制劑GF109203X和PD98059所抑制，並且不會受到JAK2的抑制劑, AG490所影響。這些結果顯示低張刺激引發STAT3絲氨酸的磷酸化是經由PKC-Erk-STAT3Ser路徑。

[ 英文摘要 ]

Cells precisely regulate their volume by various mechanisms during mitosis and osmotic challenge. The homeostasis of cell volume not only maintains volume constancy, but also controls cell function. The regulatory volume decrease (RVD) response is the process of volume adaptation observed after a hypotonic stress. STAT3 (signal transducers and activators of transcription 3) is a transcription factor, that translocation into nucleus to bind the responsive element after activation. In this study the hypotonicity-induced STAT3 activation was investigated by using whole cell lysates or nuclear protein of a cervical cancer cell line SiHa. We found that hypoosmolarity (190 ± 5 mOsm/L) resulted in phosphorylation of STAT3 on tyrosine 705 that lasted for five hours in absence of sodium vanadate, a tyrosine phosphatase inhibitor, by western blot analysis. It was further showed that hypoosmolarity induced STAT3 translocation into nucleus by immunoflureorescence study. Tyrosine phosphorylation of STAT3 was further enhanced by the combined use of hypoosmolarity and sodium vanadate. In addition, hypoosmolarity also induced the phosphorylation of STAT3 on serine 727 and ErK (extracellular signal-regulated protein kinase) 1/2. These phenomena were confirmed further by western blotting using nuclear extracts and MEK inhibitor PD 98059. Furthermore, serine phosphorylation of STAT3 was enhanced by PKC stimulator PMA, inhibited by PKC inhibitor GF109203X and PD 98059, and not affected JAK2 inhibitor AG490. These results indicate hypoosmolarity-induced serine phosphorylation of STAT3 is mediated by a PKC-Erk-STAT3Ser pathway.