臺灣博碩士論文加值系統

端粒在為持真核細胞染色體的穩定性上扮演著一個重要的角色, 對於細胞
長期的0生存能力 也是不可或缺的. 由於線性染色體的末端無法完整的複
製 [ 末端複製問題 ], 端粒會隨著正常細胞一次次的分裂而越來越短,
最後倒至細胞停止生長. 然而, 大多數不死性細胞株 仍就為持著穩定的
端粒長度, 顯示可能有補償末端複製問題的機轉存在. 端粒酵素是一種
核糖核酸蛋白質酵素, 它可以在染色體複製時在染色體末端加上重複序
列. 藉由加上重複 端粒序列 [ TTAGGG ], 末端複製問題即可解決, 並為
持著穩定的端粒長度, 使得細胞可以無限制的分裂. 也因此, 端粒酵素的
活化在腫瘤細胞進入不死化的過程中扮演著重要的角 色.
在本研究中, 我們以 TRAP-ELISA 方法來偵測人類尿路上皮癌的端粒酵素
活性. 結果 再 36 個表淺性癌組織中有 33 個被證明含端粒酵素活性 [
佔 91.7% ]; 侵入性癌組織方面, 36 個中有 35 個含端粒酵素的活性 [
佔 97.2% ]. 如果不考慮癌細胞的侵犯程度, 75 個癌組織有 71 個可偵
測到端粒酵素活姓 [ 佔 94.7% ]. 相反的, 26 個正常腎組織端粒酵素活
性呈陰性反應 [ 佔 0% ], 然而卻發現, 26 個位於膀胱癌旁的外表正常
膀胱黏膜之組織中有 11 個含端粒酵素的活性 [ 佔 42.3% ]. 此外本研
究中, 於 7 例屬於發炎性 反應伴隨再生的組織, 其中 3 例之端粒酵素
活性為陽性, 綜合以上結果顯示, 端粒酵素於癌病發生的早期便可能已被
活化. 另外, 8 個轉移或增生性淋巴腺組織全含有端粒酵素之 活性 [ 佔
100% ], 並且有 7 個的 [ 佔 87.5% ] 活性比其相對之組織更高, 根具
此結果吾人認為腫瘤組織中, 具高強度端粒酵素的細胞可能較頃向於佔優
勢,並容易造成細胞的轉移.
偵測端粒酵素活性也許針對早期腫瘤發生, 或對再發性腫瘤診斷是一種非
常有效的生 物指標. 然而, 是否可利用尿路組織沖洗液內脫落細胞之端
粒酵素活性的偵測, 去分析尿 路腫瘤的發生呢? 吾人結果發現, 於 36
例膀胱腫瘤沖洗液檢體中, 有 7 例為陽性反應 (敏感度為 87.5% ). 然
而在 3 例腎臟細胞癌之逆行性輸尿管導管沖洗檢體中, 只有 1 例 呈陽
性反應 ( 敏感度為 33.3 % ). 此外, 在 6 例非尿路腫瘤的病人中, 端
粒酵素活性都無法測得 ( 特異性達 100% ). 上述結果顯示, 藉測定端粒
酵素活性, 來診斷及追蹤尿路 上皮癌的發生是一種有效的方法.

Telomerase have a vital role in maintaining chromosome
stability and areessential for long term cellular viability.
Since the very ends of linear chromosome cannot replicate,
telomerase shorten in normal somatic cells eventually resulting
in growth inhibition. However, most immortal cell lines maintain
stable telomeres indicating that mechanism(s) exist to
compensate forthe end replication problem. Telomerase is an
RNA-dependent nucleoprotein enzyme capable of adding short
repetitive telomeric sequences to the end of the chromosome.
This addition of TTAGGG repeat compensates for the end
replicationproblem and stabilizes the length of telomeres,
allowing the cells to divide indefinitely. Thus,the activation
of telomerase activity had been proposed to be an important step
in the immortalization processof tumor cells. In the present
study, telomerase activity in urothelial cancer patients was
examined by using the TRAP(telomeric repeat amplification
protocol)-ELISA assay. Telomerase activity was demostrated in
33 of 36 superficial tumors (91.7%)and in 35 of 36 invasive
tumors(97.2%). Considering superficial tumors and invasive tumor
together, telomerase activity was detected in 71 tumor samples
from 75 patients (94.7%).In contrast, none of the 26 normal
kidney tissues displayed telomerase activity.However, 11 of 26
(42.3%) normal bladder tissues obtained from adjacent to
primarybladder tumors showed weak telomerase activity. In this
study, telomerase activationwas also detected in 3 of 7 (43%)
inflammatory lesions with cellular regeneration.These results
together show that telomerase activation may occur in the
earlystages of carcinogenesis. Furthermore, eight lymph nodes
exhibited telomeraseactivity (100%) and 7 of them (87.5%) showed
higher activity as compared to theirprimary tumors. This
suggests that a high level of telomerase activity may confera
propensity to dominate in a tumor tissue and may be requisite
for metastasis. Based upon the high percentage of telomerase
activity in urothelial cancertissues, it is reasonable to
propose the telomerase activity may be a useful marker for the
detection of early primary or recurrent urothelial tumors. Can
urothelial tumors be detected by assaying the telomerase
activity from exfoliatedcells in washing fluids? The results of
this study showed that telomerase could bedetected in 34 of the
36 bladder washing fluids (94.4% sensitivity) and in 7of the 8
(87.5% sensitivity) retrograde ureter catheterization and
irrigationfluids in urothelial cancer patients. Whereas,
telomerase activity was detectedin exfoliated cells from washing
fluid in only 1 of 3 renal cell carcinomas (33.3% sensitivity).
It was not detected in washing fluids from 6 individualswho were
free of urothelial tumors (100% specificity). These findings
suggestthat measuring telomerase activity in exfoliated cells
would be useful in thedoagnosis and follow-up of patients with
urothelial tumors.