CLDN6在子宫内膜癌组织中的表达及其与预后、免疫浸润的关系

Expression of Claudin-6 in endometrial carcinoma tissues and its relationship with prognosis and immune infiltration

目的基于TCGA数据库探讨紧密连接蛋白Claudin-6(CLDN6)mRNA在子宫内膜癌中的表达水平及其与预后、免疫浸润的关系。方法下载TCGA数据库中子宫内膜癌数据集,分析CLDN6 mRNA在子宫内膜癌中的表达,探讨子宫内膜癌患者CLDN6 mRNA高表达组和低表达组中位生存时间的差异,子宫内膜癌预后的危险因素采用Cox回归分析,子宫内膜癌组织中CLDN6 mRNA表达与免疫细胞浸润程度的相关性采用Spearman法分析,探讨子宫内膜癌组织中与CLDN6的共表达基因,并进行GO、KEGG富集分析。收集2021年1月至6月就诊于新乡医学院第一附属医院妇产科的20例子宫内膜癌患者的组织,采用免疫组化法验证癌组织及癌旁组织中CLDN6的表达。结果子宫内膜癌组织中CLDN6 mRNA表达水平为1.015(0.276,4.479),正常组织中CLDN6 mRNA表达水平为0.303(0.149,0.613),子宫内膜癌组织中CLDN6 mRNA表达上调(P<0.001)。CLDN6 mRNA低表达组和高表达组中位生存时间为3349 d和2614 d,与CLDN6 mRNA低表达组相比,CLDN6 mRNA高表达组中位生存时间显著缩短(P<0.001)。Cox回归分析证实,残留肿瘤分期R1&R2、组织学分级G3及CLDN6高表达是影响子宫内膜癌患者预后的影响因素。子宫内膜癌组织中CLDN6 mRNA表达与巨噬细胞等浸润程度呈显著正相关(P<0.05),与辅助性T细胞17(Th17)、中性粒细胞、调节性T细胞(Treg)等浸润程度呈显著负相关(P<0.05)。子宫内膜癌中与CLDN6存在显著相关的共表达基因有48个,共表达基因富集的分子功能主要为转录调节,KEGG信号通路主要为Hippo信号通路及分子黏附等。20例子宫内膜癌组织及配对的癌旁组织中,CLDN6在子宫内膜癌组织中高表达11例,中等表达6例,低表达3例,癌旁组织中CLDN6均无表达。CLDN6在子宫内膜癌中主要表达于细胞胞浆中。结论CLDN6高表达与子宫内膜癌不良预后有关,可能通过调控Hippo信号通路促进子宫内膜癌的发生发展。

Objective To investigate the expression level of Claudin-6(CLDN6)mRNA in endometrial carcinoma and its relationship with prognosis and immune infiltration based on TCGA database.Methods The data set of endometrial carcinoma was downloaded from the TCGA database,and the expression of CLDN6 mRNA in endometrial carcinoma was analyzed.The difference of median survival time between the higher and lower expression group of CLDN6 mRNA in endometrial carcinoma patients was compared.The risk factors of prognosis in endometrial carcinoma were analyzed by Cox regression.The correlation between CLDN6 mRNA expression and immune cell infiltration degree in endometrial carcinoma tissues was analyzed by Spearman methods.The co-expression genes of CLDN6 in endometrial carcinoma tissues were analyzed by GO and KEGG enrichment.A total of 20 patients with endometrial carcinoma from the Department of Obstetrics and Gynecology,the First Affiliated Hospital of Xinxiang Medical University between January and June 2021 were enrolled.Immunohistochemical methods were used to verify the expression of CLDN6 in carcinoma tissues and adjacent tissues.Results The expression level of CLDN6 mRNA in endometrial carcinoma tissues and normal tissues was 1.015(0.276,4.479)and 0.303(0.149,0.613).The CLDN6 mRNA was significantly over-expressed in endometrial carcinoma(P0.001).The median survival time of CLDN6 mRNA lower and higher expression group was 3,349 days and 2,614 days,and the median survival time of the CLDN6 mRNA higher expression group was significantly shorter than that of the lower expression group(P0.001).Cox regression analysis confirmed that residual tumor stage R1R2,histological grade G3 and CLDN6 high expression were influencing factors for the prognosis of patients with endometrial carcinoma.The expression level of CLDN6 mRNA in endometrial carcinoma was significantly positively correlated with the infiltration degree of macrophages(P0.05),and significantly negatively correlated with the infiltration degree of T helper cell 17(Th17),neutrophils,regulatory T cell(Treg)(P0.05).There were 48 co-expressed genes significantly related to CLDN6 in endometrial carcinoma.The molecular functions of co-expressed genes were mainly enriched in transcription regulation,and the KEGG signaling pathway were mainly enriched in Hippo signaling pathway and molecular adhesion.Among 20 endometrial carcinoma tissues and paired paracancerous tissues,CLDN6 was highly expressed in endometrial carcinoma tissues in 11 cases,moderately expressed in 6 cases,and low expressed in 3 cases,while no CLDN6 was expressed in paracancerous tissues.CLDN6 is mainly expressed in the cytoplasm of endometrial carcinoma.Conclusions Higher expression of CLDN6 is associated with poor prognosis of endometrial carcinoma and may promote the development of endometrial carcinoma by regulating Hippo signaling pathway.