甲状腺癌组织端粒酶激活与p16基因失活的关系

目的探讨甲状腺癌细胞增殖、分化与端粒酶激活及抑癌基因p16失活（缺失突变）之间可能存在的关系。方法应用TRAP、多重PCR、免疫组化法检测42例甲状腺癌与16例癌旁组织端粒酶活性、P16基因外显子2缺失、P16蛋白表达。结果甲状腺癌组端粒酶活性90．48％，高于癌旁组织（P〈0．01）；甲状腺癌p16基因外显子2纯合缺失率28．57％，相应癌旁组未检出（P〈0．01）；甲状腺癌P16蛋白表达缺失率40．48％，高于癌旁组（P〈0．05）；甲状腺癌P16蛋白表达缺失率高于p16基因外显子2缺失率。结论端粒酶激活与p16基因失活以及P16蛋白表达下调可能是甲状腺癌变过程中的重要分子事件，甲状腺癌中p16基因失活可能是端粒酶激活的一种途径。

Associations of telomerase activity and deletion of p16 gene in thyroid cancer

Objective To study the relation between telomerase activity and deletion of p16 gene in thyroid cancer. Methods Telomerase activity was detected with TRAP , p16 gene deletion with multiplex PCR and p16 protein expression with immunochemical technique in 42 cases of thyroid cancer and 16 cases normal tissues. Results Telomerase activity were significantly increased in cancer tissues （90.48%）compared to normal tissues （ P 〈 0.01 ）;The deletion rates of p16 gene exon 2 were 28.57% in thyroid cancer ,which were not detected in all tumor - adjacent tissues （ P 〈 0.01 ） ; The deletion rate of 16 protein expression in thyroid cancer was increased tissues compared to normal tissues （ P 〈 0.05）;The deletion rate of P16 protein expression in thyroid cancer were 40.48 % higher than deletion rates of p16 gene. Conclusion The activation of telomerase and deletion p16 gene and P16 protein down - expression might occur early in thyroid cancer and play a critical role in carcinogenesis and tumor development. In human thyroid cancer less of p16 gene may be a way of telomerase acti- vation.