正常鼻咽部和鼻咽癌組織之末端酵素活性－初報

Telomerase Activities in Tissues of Normal Nasopharynx and Nasopharyngeal Carcinoma – A Preliminary Report

黃仲鋒(Chung-Feng Hwang) ； 卓忠隆(Chung-Lung Cho) ； 郭士彰(Shih-Chang Kou) ； 黃純真(Shung-Chen Huang) ； 梁雲(Stephen-Wan Leung) ； 黃昭敏(Chao-Ming Huang) ； 蘇志英(Chih-Ying Su)

《中華民國耳鼻喉科醫學雜誌》 34卷2期 (1999/03) Pp. 109-113

https://doi.org/10.6286/1999.34.2.109

摘要

背景：末端染色體（telomere）是一種位於染色體末端的特殊構造，包含有數百到三萬個重複的鹽基，它在人類正常分化的細胞持續分裂老化過程中會逐漸縮短；而末端酵素（telomerase）其功能是合成末端的DNA，本身是一種核酸蛋白質，在生殖細胞及大部份惡性腫瘤組織中都存在。至於鼻咽癌與末端酵素的關係則少有報告。
方法：切片取得18件鼻咽癌及32件組織學正常之鼻咽組織並冷凍在-70°儲存，檢體經病理醫師檢查確定診斷，並以TRAP分析法測定末端酵素活性。
結果：18件鼻咽癌除了1件以外，都表現出末端酵素活性。有趣的是32件無鼻咽癌病灶之鼻咽組織中也有26件可偵測出末端酵素活性。6件無末端酵素活性者，4件是鼻咽癌經放射治療後的組織，2件是取自非病灶側之鼻咽癌病例。
結論：結果顯示末端酵素活性在鼻咽癌是很常見的。由於正常的鼻咽組織存在許多活化的淋巴細胞，而活化的淋巴細胞會表現出末端酵素活性，因此正常的鼻咽組織也可偵測出末端酵素。放射治療後的鼻咽組織由於缺乏活化淋巴系統所以無法發現此酵素活性。因此，我們建議以此酵素研究鼻咽癌時，必須把上述之各種情況列入考量才可減少誤差。

關鍵字

鼻咽癌 ； 末端酵素 ； 淋巴細胞

並列摘要

Background: Telomeres are specialized structures at the ends of chromosomes that consist of a few hundred base pairs to approximately 30 kbp. Reduction in average telomere length has been noted during normal aging in human differentiated cells. Activation of telomerase, a ribonucleoprotein that synthesizes telomeric DNA, is found in germ cells and most malignant tumors. However, there are few reports concerning about the relationship between telomerase activities and nasopharyngeal carcinoma (NPC).
Methods: Tissue Samples from 18 nasopharyngeal carcinomas (NPC) and 28 histologically normal nasopharyngeal tissue samples, which were pathologically confirmed, were obtained as frozen specimens stored at -70°C. The telomerase activity was measured by telomeric repeat amplification protocol (TRAP) assay.
Results: All 18 NPC tissues except one were telomerase-positive. Telomerase activity was detectable in 26 of 32 histologically normal nasopharyngeal tissues. Of the 6 telomerase-negative tissues, four were obtained from post-irradiated, tumor-free nasopharynx and two from non-lesion sides of two NPC patients.
Conclusions: Our results revealed that activation of telomerase activity was frequently present in NPC tissue. Detectable telomerase activities were observed in most normal nasopharyngeal tissues probably because there are many activated lymphocytes that retain telomerase activities. We could not detect telomerase activities in post-irradiated nasopharyngeal tissues whose lymphoid system had been destroyed by irradiation. Therefore, when we study the relationship between NPC and telomerase activities, it is important to take the above phenomenon into consideration.

並列關鍵字

nasophyaryngeal carcinoma ； telomerase ； lymphocyte