乳腺癌易感基因1在家族性甲状腺癌中的表达及临床意义

Expression and clinical significance of BRCA1 in familial thyroid carcinoma

目的探讨家族性甲状腺癌（familial thyroid callcer，FTC）组织中乳腺癌易感基因1（BRCAl）的表达及其与临床病理特征间的关系。方法收集2011年3月至2016年5月在大连大学附属中山医院手术切除的37例FTC标本（家族组）．35例散发性甲状腺癌组织标本（散发组），35例正常甲状腺组织标本（对照组）。分别采用免疫组织化学荧光染色法和实时定量聚合酶联反应技术（RT．PCR）检测各标本BRCAl蛋白及mRNA的表达。结果BRCAlmRNA在家族组中表达为（0．210±0．025），相比散发组（0．943±0．021）和对照组（1．001±0．087）明显下调（P〈0．01）。BRCAl蛋白在家族组中表达阳性率为56．2％（21／37），明显低于散发组（85．7％，30／35）和对照组（94.3％，33／30）（P〈O．05）。BRCAI蛋白的表达程度与FrC的双侧癌、淋巴结转移、侵袭被膜、年龄低于30岁、同家族中超过2例等临床病理特征具有相关性（P〈0．05）。结论BRCAl蛋白及mRNA在FTC组织中低表达，BRCAl蛋白的表达与FTC的病理特征相关，有望成为评估FTC生物学行为的新标志物。

Objective To investigate the expression of BRCA1 in familial thyroid cancer （FI＇C） and the relationship between BRCA1 expression and clinicopathologic features. Methods The expression of BRCA1 protein and mRNA was detected respectively by immunohistochemistry and RT-PCR in 37 FFC tissues,35 spo- radic thyroid carcinoma tissues and 35 normal thyroid tissues. Results BRCA1 mRNA expression was signifi- cantly downregulated in FTC （0.210±0.025） compared with sporadic thyroid carcinoma（0.943±0.021） and nor- mal thyroid tissues （1.001±0.087）（P〈0.01 ）. The positive rate of BRCA1 protein expression was significantly lower in FYC （56.8%, 21/37） than that in sporadic thyroid carcinoma（85.7%, 30/35） and normal thyroid tissues（94.5%, 33/ 35） （P〈0.05）. There was a correlation between BRCA1 protein expression and F＇I＇C clinicopathologic features（P〈 0.05）. FTC patients with lower BRCAI protein expression tended to have higher risk for bilateral carcinoma,lymph node metastasis, capsular invasion, morbidity under 30 years old and more than 2 patients in a family. Conclu- sions The expression of BRCA1 protein and mRNA is downregulated in FTC. BRCA1 protein might serve as a potential biomarker for predicating biological behavior and prognosis of FTC.