論文名稱:

金屬離子催化蛋白水解酶-13在口腔上皮細胞癌化過程之表

 

The Expression of Matrix Metalloproteinase-13 in Malignant Process of Oral Keratinocyte

研究生:

蔣文政  Wen-Cheng Chiang

 

(以作者名查詢陽明大學館藏系統)

 

(以作者名查詢全國圖書書目資訊網)

指導教授:

張國威  Kuo-Wei Chang

        學位類別:

碩士

        學校名稱:

國立陽明大學

系所名稱:

口腔生物研究所

            學號:

39017008

          學年度:

91

          語文別:

中文

          出版年:

92

全文說明:

電子全文

        論文頁數:

86

摘要:

在癌細胞侵襲轉移過程中,蛋白水解酶的角色備受囑目,因癌細胞必須操控蛋白水解酶裂解基底膜以及細胞外基質,以利其侵犯其他組織器官。蛋白水解酶中以金屬離子催化蛋白水解酶(MMPs)的表現在癌細胞侵襲轉移的關係上至為關鍵,亦即在癌細胞侵襲能力擴張之際,MMPs的表現與活性同步升高。先前之刪減雜合術初步研究分析,比較口腔鱗狀上皮細胞癌與非癌配對組織,發現MMP-13異常地過量表現於口腔鱗狀上皮細胞癌,而此一蛋白水解酶於口腔鱗狀上皮細胞癌生成過程之角色仍未明朗。本實驗上首先比較正常口腔角質上皮細胞與口腔鱗狀上皮細胞癌細胞株之MMP-13 mRNA表現量,發現多數癌細胞株中MMP-13 mRNA表現量明顯超過正常口腔角質上皮細胞之表現量。在36組口腔鱗狀上皮細胞癌與非癌配對組織上,探討MMP-13 mRNA表現之差異。結果MMP-13 mRNA在口腔鱗狀上皮細胞癌組織之平均表現量(1.83±0.21)明顯高於非癌配對組織(0.45±0.12)(p<0.0001);在與臨床及病理發現交叉分析顯示,MMP-13 mRNA表現量與患者年齡、腫瘤發生部位、癌細胞介化情形、淋巴結轉移以及癌症分期等並無明顯相關。在MMP-13蛋白表現上,於44例口腔鱗狀上皮細胞癌、16例非癌配對組織以及21例口腔癌前病灶組織上,以免疫組織化學染色法呈現MMP-13表現量。定量分析顯示,口腔鱗狀上皮細胞癌MMP-13強陽性率(100%)明顯高於非癌配對組織(38%)以及口腔癌前病灶組織(24%)(p<0.0001);但非癌配對組織與口腔癌前病灶組織之MMP-13表現並無明顯差異。故MMP-13之表現增加主要發生在由口腔癌前病灶發展至口腔鱗狀上皮細胞癌之階段。在以綠茶含量最多之多酚類-綠茶素(EGCG)處理口腔鱗狀上皮細胞癌細胞株,可見隨著劑量升高,綠茶素抑制MMP-13 mRNA表現以及蛋白產量與活性之效益更形顯著。顯示在某些濃度範圍之綠茶素在口腔癌之化學預防及治療上,可能藉由抑制MMPs之表現與活性進而產生作用。

 

Degradation of basal lamina and stromal extracellular matrix is crucial for invasion and metastasis of malignant cells. This process is initiated by proteinases, and increased proteinases expression or activity has been linked to malignancy and invasion of tumor cells. Studies performed over the last decade have revealed that matrix metalloproteinases (MMPs) play a pivotal role in tumor invasion. Based on our previous subtractive hybridization library observation, and by comparing oral squamous cell carcinoma (OSCC) tissue with non-cancerous matched tissue (NCMT), MMP-13 mRNAs were highly expressed in OSCC tissue. Since the roles of MMP-13 in carcinogenesis were not clearly addressed, this study has extended our previous findings by examining the expression of MMP-13 in oral keratinocytes and OSCC cells both in vitro and in vivo in this study. Initially, the expression of MMP-13 mRNAs were examined in 2 normal human oral keratinocytes (NHOKs) and 3 OSCC cell lines, and the result showed that MMP-13 mRNAs were detected in most OSCC cell lines but not in NHOKs. When OSCC was compared with NCMT from 36 individuals with OSCC, the mean MMP-13 mRNA expression level (1.83 ± 0.21) of OSCC was significantly higher than that of NCMT (0.45 ± 0.12)(p < 0.0001). No significant correlation was found between MMP-13 mRNA expression and clinicopathological features. The expression of MMP-13 protein was investigated on tissue specimens of 44 OSCC, 16 NCMT and 21 oral pre-cancer lesion (OPL) by using immunohistochemistry. There were significant differences between OSCC (MMP-13 ++: 100%) and NCMT (MMP-13 ++: 38%) or OPL (MMP-13 ++: 24%) (p < 0.0001). On the other hand, the difference between OPL and NCMT is not statistically significant. It is deduced that MMP-13 expression was related to OPL develop to OSCC stage. To identify the effect of main green tea polyphenol, EGCG, on MMP-13, RT-PCR, western blot analysis and zymography were performed. It revealed that EGCG reduced the expression of MMP-13 mRNA in higher EGCG concentration (> 5 μM). In addition, the production and activity of MMP-13 were suppressed by EGCG. Therefore, it is tentatively concluded that EGCG might exert chemopreventive or therapeutic effects on neoplasm through suppressing MMPs expression and activity.