甲状腺乳头状癌组织中线粒体DNA含量的变化

 目的 探讨线粒体DNA（mtDNA）含量变化在甲状腺乳头状癌发生中的作用及其意义。方法 应用TaqMan实时荧光定量聚合酶链反应检测29例甲状腺乳头状癌，14例甲状腺腺瘤，11例结节性甲状腺肿及其配对正常甲状腺组织的mtDNA含量变化，并结合甲状腺乳头状癌主要临床病理参数进行分析。结果 （1）29例甲状腺乳头状癌中mtDNA相对含量为224.13±217.24；配对癌旁正常甲状腺组织mtDNA相对含量为88.69±44.06，明显高于癌旁正常甲状腺组织（P＜0.01）。与癌旁正常甲状腺组织相比，甲状腺乳头状癌中mtDNA含量增加、无明显变化和减少的比例为21：2：6。（2）25例甲状腺良性病变中mtDNA相对含量为129.48±105.27；配对瘤旁正常甲状腺组织mtDNA相对含量为89.44±29.75。甲状腺良性病变mtDNA含量与瘤旁正常甲状腺组织无显著差异，但低于甲状腺乳头状癌组（P＜0.05）。（3）甲状腺良性病变中，甲状腺腺瘤和结节性甲状腺肿的mtDNA含量差别无统计学意义。（4）甲状腺乳头状癌的mtDNA含量变化与患者年龄、肿瘤大小、淋巴结转移等临床病理参数无关（P＞0.05）。结论 mtDNA含量增加与甲状腺乳头状癌发生有关，但与其临床病理参数未见相关性，是肿瘤发生的早期事件。

Determination of mtDNA content in papillary thyroid carcinoma by TaqMan real-time fluorescent quantitative PCR

Objective To elucidate the relationship between thyroid tumorigenesis and the mtDNA content alterations. Methods The mtDNA content in 54 pairs of normal and thyroid neoplasm samples were examined by TaqMan quantitative real-time polymerase chain reaction analysis, including 29 papillary thyroid carcinomas, 14 thyroid adenomas and 11 nodular goiters. and further to explore the possible correlations of the mtDNA content in papillary thyroid carcinoma (PTC) with clinicopathologic parameters. Results The relative mtDNA content was increased in the PTC samples compared to their normal thyroid tissues taken from the same individual (224.13±217.24 vs. 88.69±44.06; P<0.01), also, mtDNA content in PTC samples was higher than that in the benign thyroid lesions（224.13±217.24 vs. 129.48±105.27; P<0.05）. However, no significant difference was observed in mtDNA content between the benign thyroid lesions and matched normal tissues, nor between the thyroid adenoma and nodular goiter （all P>0.05）. We further analyzed the mtDNA content in 29 paired tumor and normal DNA from patients with PTC. Our results showed that of the 29 pairs, 21 (72.41%) had increased mtDNA content in the tumor samples, 6 (20.69%) harbored less mtDNA content in the tumor and 2 (6.90%) did not show any difference between the normal and the tumor DNA. Additionally, mtDNA content changes in PTC samples did not correlate with any clinical pathological features such as age, tumor size, lymph node metastasis, nor conclusive stage （all P>0.05）. Conclusions The findings indicate that mtDNA content increased during thyroid cancer development，the increase might occur in the early stages of thyroid tumorigenesis.The role of mtDNA content changes in carcinogenesis warrants further investigation.