Tahara H, Kuniyasu H, Yokozaki H, Yasui W, Shay J W, Ide T, Tahara E
Department of Cellular and Molecular Biology and First Department of Pathology, Hiroshima University School of Medicine, 1-2-3 Kasumi, Minami-Ku, Hiroshima 734, Japan.
Clin Cancer Res. 1995 Nov;1(11):1245-51.
Recent evidence indicates that telomerase activity may be necessary for cell immortality, which is required for the sustained and indefinite growth of most malignant cells. We analyzed telomerase activity in gastric and colorectal cancers and in gastric and colorectal precancerous lesions to determine whether malignant progression depends on the activation of telomerase and at what stage of carcinogenesis cells have detectable telomerase activity. Telomerase activity was measured by the telomeric repeat amplification protocol assay and was detected in 17 (85%) of 20 primary gastric carcinoma tissues and in 19 (95%) of 20 primary colorectal carcinomas, regardless of tumor staging and histological types. All nodal metastases, peritoneal metastases, and a recurrent gastric cancer tumor were positive. All cell lines established from gastric and colorectal cancers contained telomerase activity. In precancerous lesions, 10 (100%) of 10 colorectal tubular adenomas were telomerase positive, in addition to 3 (23%) of 13 gastric intestinal metaplasias and 1 (50%) of 2 gastric adenomas, whereas the corresponding gastric normal mucosas as well as colorectal mucosas were negative. These results indicate overall that reactivation of telomerase may occur at an early stage of carcinogenesis and may correlate well with malignant progression of gastric cancer. Telomerase activity thus may serve as a powerful additional tool for cancer diagnosis.
最近的证据表明，端粒酶活性可能是细胞永生化所必需的，而细胞永生化是大多数恶性细胞持续和无限生长所需要的。我们分析了胃癌和结直肠癌以及胃癌和结直肠癌癌前病变中的端粒酶活性，以确定恶性进展是否依赖于端粒酶的激活，以及在致癌过程的哪个阶段细胞具有可检测到的端粒酶活性。通过端粒重复序列扩增法检测端粒酶活性，在20例原发性胃癌组织中的17例（85%）以及20例原发性结直肠癌中的19例（95%）检测到端粒酶活性，无论肿瘤分期和组织学类型如何。所有的淋巴结转移、腹膜转移以及一例复发性胃癌肿瘤均呈阳性。所有从胃癌和结直肠癌建立的细胞系都含有端粒酶活性。在癌前病变中，10例大肠管状腺瘤中的10例（100%）端粒酶呈阳性，此外，13例胃黏膜肠化生中的3例（23%）以及2例胃腺瘤中的1例（50%）端粒酶呈阳性，而相应的胃正常黏膜以及结肠黏膜均为阴性。这些结果总体表明，端粒酶的重新激活可能发生在致癌过程的早期，并且可能与胃癌的恶性进展密切相关。因此，端粒酶活性可能作为癌症诊断的一个有力辅助工具。
