甲状腺乳头状微小癌淋巴结转移相关miRNAs的鉴定及机制研究

Modern ultrasound technology and US-guided fine needle aspiration biopsy (US-FNA) are the effective methods to diagnose papillary thyroid micro-carcinoma (PTMC). However, early cervical lymph nodes metastasis（CLNM）which cannot be detected by ultrasound is the major determinant of treatment option and disease prognosis. Studies show that expression of the specific miRNAs is probably associated with PTMC CLNM. Our previous study found that the expressions of 19 miRNAs including miRNA 1270 were associated with CLNM based on the genome wide LNM related miRNAs expression profile of human PTMC with CLNM as well as those without CLNM. The aim of the current project is to testify the correlation between the expression of miRNAs and CLNM in more than 300 PTMCs. We will also investigate that how these 2 or 3 key miRNAs regulate CLNM by cell lines and nude mice model. Furthermore，we will test whether the combination of miRNA expression profile with other molecular markers (RET / PTC, RAS, PAX8/PPARγ and BRAF), sonographic features and US-FNAB can significantly increase the accuracy of CLNM prediction. We hope that the current study will offer clue for preoperative evaluation, early diagnosis of CLNM and treatment option.

现代超声技术及超声引导下细针穿刺抽吸（US-FNAB）是诊断甲状腺乳头状微小癌（PTMC）的有效手段，但是否存在超声不可探测颈部淋巴结转移（CLNM）是决定治疗方案和预后的重要指标。众多研究表明一些特定miRNAs表达水平与肿瘤转移存在功能性相关。本课题组基于对PTMC无/有CLNM标本miRNAs表达谱分析提示miRNA-1270等19个 miRNAs与PTMC-CLNM倾向相关。本研究拟在大样本范围（>300例）验证其在PTMC表达水平及与CLNM的相关性，并通过甲癌细胞株、裸鼠模型阐述关键2-3个miRNAs在甲癌转移过程中的作用及分子机制。在此基础上分析CLNM相关miRNAs与已知分子标记物（RET/PTC、RAS、PAX8/PPARγ和BRAF）预测CLNM的叠加效应，并与超声及US-FNAB联合，优化术前评估流程，为PTMC CLNM早期诊断和治疗方案选择提供可靠依据。

现代超声技术及超声引导下细针穿刺抽吸活检（US-guided fine needle aspiration biopsy, US-FNAB）是诊断甲状腺乳头状癌（papillary thyroid carcinoma，PTC）及淋巴结转移的有效手段，但是否存在超声不可探测的颈部淋巴结转移是影响治疗方案和预后的重要因素。本课题组基于对转移性和非转移性甲状腺乳头状癌组织标本非编码RNAs表达谱分析鉴定，筛选与验证发现miR-324-5p、NONHSAT076754及下游分子FN1等基因在转移性甲状腺癌中的表达水平显著升高。临床小样本量检测miR-324-5p在FNA灌洗液中的相对表达量，结果提示miR-324-5p能够预测低危PTC中的大部分CLNM病例，在一定程度上弥补传统超声在鉴别CLNM中的不足。体外实验提示miR-324-5p具有促进PTC细胞侵袭转移的作用，课题组进而通过生物信息学方法预测、荧光素酶报告实验证实PTPRD为miR-324-5p的下游直接调控分子，进一步研究发现抑制PTPRD能够上调CEBPD表达，并诱导巨噬细胞M2表型。上述分子联合超声特征以及US-FNAB，是否有望为优化术前诊断甲状腺结节及评估LMN流程提出切实方案，仍需大样本验证。