MOLECULAR MECHANISMS DISTINGUISH FOLLICULAR ADENOMA/FOLLICULAR CARCINOMA/THYROID

区分滤泡性腺瘤/滤泡性癌/甲状腺的分子机制

• 批准号: 6245438
• 负责人: MARTHA A ZEIGER
• 金额: $ 2.23万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-05 至 1997-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6245438
• 关键词: adenoma; carcinoma; chromosome aberrations; clinical research; denaturing gradient gel electrophoresis; enzyme activity; human subject; loss of heterozygosity; molecular oncology; nucleic acid repetitive sequence; polymerase chain reaction; telomerase; thyroid neoplasm

We examined genomic DNA from 31 follicular neoplasms, 20 follicular carcinomas (FC) and 11 follicular adenomas (FA) for loss of heterozygosity (LOH) using PCR-based microsatellite polymorphisms for all chromosomal arms. Although there was a tendency for FC to exhibit a greater percent LOH on certain chromosomal arms than the FA, there was no statistically significant difference between LOH seen in PA. However, when we examined more closely the follicular neoplasms we found that there was a significant difference between the Hurthle cell variant of follicular carcinoma and Hurthle cell variant of follicular adenoma. We, therefore, further pursued this and found that Hurthle cell carcinomas (RC) had significantly greater chromosomal abnormalities than Hurthle cell adenomas (HA) on chromosomal a=Iq and 2p and that all Hurthle cell neoplasms (HN) had a significantly greater frequency of alterations on chromosomal arm lp compared to normal thyroid glands. In an attempt to further evaluate the role of these genetic alterations in Hurthle cell tumorigenesis, we examined chromosomal arms lp, Iq and 2p in 19 HC and 32 KA. More than 15 primers that flanked CA-repeat regions on each chromosomal arm were radiolabelled. DNA was PCR- amplified using the radiolabelled primers, and PCR products were separated by electrophoresis on 6% denaturing urea-polyacrylamide gels. Allelic loss was recorded if the signal intensity of one allele in informative cases was at least 50% decreased in the tumor DNA as compared to corresponding normal DNA; allelic gain was considered if additional bands were noted. Differences in allelic alterations were significantly greater in HC than HA by Fisher's exact test (p<0.05) at six loci 1p:D1S224,D1S207)(Iq:D1SI660)(2p:D2S1240,D2S1788,D2S1394). These results strongly support the thyroid tumor progression model and implicate chromosomal arms lp,lq,and 2p in the tumorigenesis of Hurthle cell neoplasms. Additional mapping of these regions is needed to further elucidate the underlying molecular genetic mechanisms responsible. Finally, because the differential diagnosis of follicular neoplasms still posed a clinical dilemma without solution, we pursued another molecular market, namely telomerase, to determine whether or not it would distinguish FA from PC. Telomerase activity was detected in 11 of 11 carcinomas, in 5 of 23 benign follicular adenomas and in none of 22 matched normal thyroid tissues. In this series the telomerase assay had a specificity of 74% and a sensitivity of 100%. Because of this preliminary data we have instituted a multi-institutional study looking at telomerase activity in the differential diagnosis of follicular neoplasms. And finally, because of the promising data with Hurthle cell neoplasms, we plan to further map the chromosomal regions that have abnormalities on lp, Iq and 2p in Hurthle cell carcinomas.

我们检测了31例滤泡性肿瘤，20例滤泡性肿瘤， 癌（FC）和11例滤泡性腺瘤（FA）， 杂合性（洛合性），使用PCR为基础的微卫星多态性， 所有的染色体臂。 尽管FC有表现出 在某些染色体臂上的洛缺失百分比大于FA， PA中观察到的洛缺失之间无统计学显著差异。 然而，当我们更仔细地检查滤泡肿瘤时， 发现Hurthle细胞和正常细胞之间 滤泡癌变异型和滤泡癌Hurthle细胞变异型 腺瘤 因此，我们进一步追求这一点，并发现Hurthle 细胞癌（RC）有显着更大的染色体异常 在染色体a=Iq和2 p上， Hurthle细胞肿瘤（HN）的发生率显著高于 与正常甲状腺相比，染色体臂lp上的改变。 为了进一步评估这些基因改变的作用， 在Hurthle细胞肿瘤发生中，我们检查了染色体臂lp，Iq和 19 HC和32 KA中的2 p。 CA重复序列侧翼引物15个以上 对每个染色体臂上的区域进行放射性标记。 DNA是PCR- 使用放射性标记的引物进行扩增，并将PCR产物 通过在6%变性尿素-聚丙烯酰胺凝胶上电泳分离。 如果一个等位基因的信号强度在一个等位基因缺失记录。 信息性病例的肿瘤DNA至少减少50%， 与相应的正常DNA相比;如果 注意到另外的条带。 等位基因改变的差异是 通过Fisher精确检验，HC显著大于HA（p<0.05）， 6个位点：1 p：D1 S224，D1 S207，1 q：D1 SI 660，2 p：D2 S1240，D2 S1788，D2 S1394。 这些结果强烈支持甲状腺肿瘤进展模型， 染色体臂lp、lq和2 p与Hurthle肿瘤发生有关 细胞肿瘤 需要对这些区域进行额外的绘图， 进一步阐明潜在的分子遗传机制 责任 最后，由于滤泡性肿瘤的鉴别诊断 仍然提出了一个没有解决方案的临床困境，我们追求另一个 分子市场，即端粒酶，以确定是否它 将FA与PC区分开来。 11例端粒酶活性阳性 23例良性滤泡性腺瘤中5例， 22个匹配的正常甲状腺组织。 在这个系列中， 特异性为74%，敏感性为100%。 因为如此 初步数据，我们已经建立了一个多机构的研究， 端粒酶活性检测在滤泡性卵巢癌鉴别诊断中的应用 肿瘤。 最后，由于Hurthle细胞的数据很有希望， 肿瘤，我们计划进一步绘制染色体区域， 在Hurthle细胞癌中lp、Iq和2 p的异常。