基于TCGA数据库挖掘甲状腺乳头状癌淋巴结转移相关的突变基因及其机制探讨

Search of the mutated genes related to lymph node metastasis of papillary thyroid carcinoma based on TCGA database and explore its mechanisms

目的:挖掘并筛选与甲状腺乳头状癌(papillary thyroid carcinoma,PTC)淋巴结转移相关的突变基因及其潜在的机制。方法:从TCGA数据库获得377例PTC患者的测序数据及完整的临床资料,并分为淋巴结转移组(LM,n=212)与无淋巴结转移组(NLM,n=165)。利用R语言(v3.6.2)对转移组特有的突变基因进行富集分析。采用String在线软件绘制蛋白互作网络,Cytoscape软件筛选网络中的核心基因。在UALCAN网站上验证基因表达量与淋巴结转移之间的关系。利用荧光实时定量PCR测定候选基因在细胞系中mRNA的表达量。结果:一共筛选出1197个仅在LM组发生突变的基因,它们主要富集在黏着连接、细胞黏附分子(cell adhesion molecules,CAMs)通路。CAMs通路的核心基因ITGB1与VCAN的表达量与淋巴结转移相关。与正常甲状腺细胞系相比,VCAN基因在PTC细胞系TPC-1和B-CPAP中mRNA的表达量较高,尤其是B-CPAP细胞系。结论:CAMs通路可能是PTC淋巴结转移相关机制之一,其中VCAN基因可能是潜在的分子标志物。

Objective:To search and screen mutated genes and underlying mechanisms related to lymph node metastasis of papillary thyroid carcinoma(PTC).Methods:The sequencing data and complete clinical data of 377 patients with PTC from the TCGA database were obtained and divided it into two groups:The lymph node metastasis group(LM,n=212)and the non-lymph node metastasis group(NLM,n=165).R language(v3.6.2)was used for enrichment analysis of the specific mutated genes in LM group.String online software was used to draw the protein interaction network,and Cytoscape software was used to screen the core genes in the network.The association of gene expression level and lymph node metastasis was examined on the UALCAN website.RT-qPCR analysis was implemented to determine the mRNA expression level of candidate genes in cell lines.Results:A total of 1197 mutated genes which were seen in LM group exclusive were screened out,and they were mainly enriched in the adherens junction and cell adhesion molecules(CAMs)pathways.The expression level of ITGB1 and VCAN,the core genes of CAMS pathway,were related to lymph node metastasis.Compared with the normal thyroid cell lines,the expression level of VCAN was much higher in PTC cell lines(TPC-1,B-CPAP),especially in B-CPAP.Conclusion:CAMs pathway may be one of the mechanisms related to lymph node metastasis of PTC,and VCAN may be potential molecular marker.