| Abstract: | 碳酸酐 (carbonic anhydrase; CA)是一種含鋅離子的金屬酵素。其中包含許多不同的異構。而存在於細胞質的CA I, CA II和CA III被發現廣泛存在於肝細胞及其他不同組織中。本研究主要在評估CA I, CA II和CA III於肝癌及乳癌中表現的程度和腫瘤細胞侵犯的角色。本研究分別利用CA活性分析法、西方墨點分析法和RT-PCR等方法，分析60個肝癌和60個乳癌患者手術後癌瘤組織及週邊正常組織其CA的活性、蛋白質的表現形態及mRNA的差異性表現。結果發現，在60個肝癌患者其CA活性和蛋白表現在腫瘤部位都顯著低於週邊正常組織(P<0.01)，而mRNA層次也是顯著下降(P<0.001)；另外，利用免疫組織化學分析法(immunohistochemistry)也證實在腫瘤部位的CA I, CA II和CA III的蛋白質表現也是有顯著的下降。我們更進一步發現在肝癌組織中其TMN stage與CA II蛋白表現有顯著的相關性(P<0.001)。而在60個乳癌患者中，我們發現其CA活性在腫瘤部位比週邊正常組織卻有顯著的上升(P<0.01)；CA II的蛋白表現和CA活性一樣在腫瘤部位有顯著的上升(P<0.001)。而CA I和CA III的蛋白質表現則是有意義的下降(P<0.01)。而在mRNA層次也是和蛋白質表現有相同的結果。另外我們更進一步探討乳癌組織中CA活性與其臨床上一些數據的相關性分析。結果發現CA活性和腫瘤大小有顯著的相關性(R= 0.48; P<0.05)，而其CA活性也隨著腫瘤期數的上升而上升。因此，本研究發現在肝癌及乳癌的腫瘤組織中，CA活性及其CA I, CA II和CA III的蛋白表現及mRNA層次有不同的表現。我們推論在肝癌腫瘤部位的CA I, CA II和CA III減少，可能有助於癌細胞的活動性進而有利於腫瘤成長與轉移。另外我們也發現CA在不同癌組織中的表現會隨著組織的不同而有所差異，這些不同的變化可以提供我們在不同癌症治療上的一個新的思維。
英文摘要 Cytosolic carbonic anhydrases (CAs), including CAI, CAII and CAIII are presented in normal hepatocytes. This study was aimed to investigate the expression status of CAs in hepatocellular carcinomas (HCC) and breast cancer and the role of tumor progression. The activity, protein expression pattern and messenger RNA of cytosolic CA were analyzed by CA activity analysis, Western blotting and RT-PCR in 60 human hepatocellular carcinomas and 60 human breast cancer surgical specimens. The result shows that in each of 60 HCC, CA activity and protein expression in tumor area is significantly lower than that of paired adjacent normal tissues (P<0.01), and mRNA expressions in tumor areas are also reduced (P<0.001). Furthermore, the immunohistochemical studies have further confirmed this reduction of CAI, CAII and CAIII protein expression in tumor areas. There is a statistically significant reduction in the expression of cytosolic CAII in poorly differentiated cancer (P < 0.001). Furthermore, in 60 breast cancer patients, the result showed that CA activity and CA II protein expression in tumor area was significantly higher than that of paired adjacent normal tissues (P < 0.01), while the CA I and CA III protein expression was lower (P < 0.001). Furthermore, further linear regression analysis has showed that the tumor size positively correlated with CA activity in tumor tissue samples (R=0.48, P<0.05). In addition, further statistical analysis for clinic pathological parameters revealed that CA activity was significantly increased in patients with metastasis (P <0.05). CA activity in tumor tissue might reflect the severity of invasion of breast cancer and various CA inhibitors might be selectively used as potential anti-metastasis agents according to tumor size. |
