摘要
Enolase為一參與在醣解作用的酵素，負責將2-phosphoglycerate 代謝成phosphoenolpyruvate。醣解作用的目的是將葡萄糖降解，產生末端產物pyruvate；此末端產物進入粒線體後即投入TCA cycle中，因此細胞便能獲得ATP，達成能量生產的目的。 在哺乳類動物中Enolase有三種型態，ㄧ型(ENO1)表現在大多數細胞，二型(ENO3)表現於肌肉細胞，三型(ENO2)則在神經細胞。 Enolase長期以來ㄧ直被定位在能量代謝上，然而由文獻瀏覽我們發現ENO1與癌症的相關性，無論是在DNA、mRNA與蛋白質層次上在癌症中表現量皆有異常之現象。在過去的研究中，對於ENO1在癌症中之角色是正向或是負向影響尚未釐清，分別有文獻指出ENO1可能扮演致癌基因或抑癌基因。在本論文中偵測ENO1於肺癌及食道癌病人組織中的表現量，發現ENO1於肺癌組織中表現量較高，但在食道癌中卻沒有差異。接著將外緣性ENO-1或是ENO-1 shRNA高量表達於細胞中，發現ENO-1特別地只刺激肺癌細胞株的生長，對其他細胞株並無明顯作用，且ENO1刺激細胞生長決定於其細胞內的位置，上述之結果顯示ENO1促進細胞轉型可能具有組織(肺部)特異性。然而，ENO1穩定表現細胞株(H1299)在MTT、colony formation assay、cell cycle regulation和drug sensitivity卻與控制組沒有差異，本論文將針對這部分差異進行討論。
並列摘要
Enolase is a glycolytic enzyme (2-phospho-D-glycerate hydrolyase), catalyzing the biotransformation of ephosphoenolpyruvate from 2-phosphoglycerate. The cellular significance of glycolysis is to decompose glucose, leading to the production of pyruvate, which is then translocated to mitochondria where ATP is generated through a series of biochemical reaction termed tricarboxylic acid cycle (TCA cycle). In mammals, enolase has three isoenzymes, type 1(ENO1) located at most tissues, type 2(ENO3) at muscle and type 3(ENO2) at nervous tissue. Conflictingly, ENO-1 has been reported to be either up- or down-regulated in human cancers. In this thesis, we detected the higher expression level of ENO1 in cancer part of lung cancer tissue, but not esophageal cancer tissues. Afterward exogenous EGFP-ENO1 and ENO1-siRNA were overexpressed in various cell lines. The results showed the transient expressing of ENO1 promotes cell proliferation in lung cancer cell lines (H1299 and H460) and this promotion is largely dependent on subcellular localization of ENO1. These data indicated the role of ENO1 in cell transformation is tissue specific. However, further analysis (MTT, colony formation assay, cell cycle regulation and drug sensitivity) suggested the H1299 ENO1 stable clone did not promote cell transformation.