TUMOR DEVELOPMENT AND TELOMERASE ACTIBITY IN HUMAN COLORECTAL TUMORS

端粒酶维持染色体末端端粒的不稳定性，对肿瘤的发生和细胞的永生化起着重要的作用。我们探讨了端粒酶在结直肠癌发生发展中的作用机制。应用端粒重复序列扩增技术对13例结直肠癌、9例早期癌、32例进展期结直肠癌、5例转移性结直肠癌和30例正常大肠黏膜进行端粒重复序列扩增。端粒酶阳性率和平均活性在正常粘膜分别为13.3%和18.0，腺瘤分别为15.4%和29.9%，早期癌分别为77.8%和65.8%，进展期分别为93.8%和97.0%，转移瘤分别为100%和161.3。肿瘤直径大于6 cm，分化较差的癌和粘液癌(p=0.009，0.001)，侵犯固有肌的癌(p=0.08)活性较高。端粒酶活性取正常粘膜平均活性的两倍作为肿瘤标记物。其灵敏度为0.89，特异度为0.98，准确度为0.93。端粒酶在肿瘤的发生发展中起着重要作用，被认为是一种有用的肿瘤标志物。

Telomerase keeps instability of chromosomes with telomere in terminals of them and plays a important role for development of carcinomas and immortality of cells. We investigated a mechanism of telomerase-expression in carcinogenesis of colorectal carcinomas. Thirteen adenomas, nine carcinomas in early stage, 32 carcinomas in progressive stage, five metastatic tumors, and 30 normal mucosae resected surgically from the patients with colorectal cancer were examined with the telomeric repeat amplification protocol. The results of the positivity and mean activity of telomerase are 13.3% and 18.0 in normal mucosae, 15.4%, 29.9 in adenomas, 77.8%, 65.8 in carcinomas in early stage, 93.8%, 97.0 in carcinomas in progressive stage, and 100%, 161.3 in metastatic tumors. High activity was shown in carcinomas whose diameter is larger than six cm, in poorly defferentiated carcinomas and mucus carcinomas (p=0.009,0.001 respectively), in carcinomas invades proprial muscle (p=0.08). Telomeraseactivity was cut off by the two times of mean activity of normal mucosae and calculated as a tumor marker. Its sensitivity is 0.89, its specificity 0.98, and its accuracy 0.93. Telomerase plays a important role for carcinogenesis and development of carcinomas as well as it is considered as a useful tumor marker.