非小细胞肺癌患者血清外泌体miR-181a-5p和lncRNA CCAT1表达变化及其临床意义

Expression changes of miR-181a-5p and lncRNA CCAT1 in serum exosomes of patients with non-small-cell lung cancer and their clinical significance

目的探讨非小细胞肺癌(NSCLC)患者血清外泌体微小RNA-181a-5p(miR-181a-5p)、长链非编码RNA(lncRNA)结肠癌相关转录因子1(CCAT1)表达变化及其与患者临床病理特征和预后的关系。方法选择NSCLC患者103例(观察组)、体检健康的志愿者27例(对照组),采集两组外周静脉血,离心留取血清,提取血清外泌体。采用实时荧光定量PCR法检测两组血清外泌体miR-181a-5p、lncRNA CCAT1表达。比较两组外泌体miR-181a-5p、lncRNA CCAT1表达,分析NSCLC患者血清外泌体miR-181a-5p表达与lncRNA CCAT1表达的关系以及二者表达与患者临床病理特征的关系。采用Kaplan-Meier法分析血清外泌体miR-181a-5p、lncRNA CCAT1表达与NSCLC患者5年总体生存率的关系。采用Cox比例风险回归模型分析NSCLC患者预后不良的危险因素。结果观察组血清外泌体miR-181a-5p相对表达量明显低于对照组,血清外泌体lncRNA CCAT1相对表达量明显高于对照组(P均<0.01)。Pearson相关分析显示,NSCLC患者血清外泌体miR-181a-5p相对表达量与lncRNA CCAT1相对表达量呈负相关关系(P<0.01)。NSCLC患者血清外泌体miR-181a-5p、lncRNA CCAT1表达均与肿瘤临床分期、淋巴结转移有关(P均<0.05),而与性别、年龄、吸烟史、肿瘤直径、病理类型、组织分化程度无关(P均>0.05)。103例NSCLC患者治疗后随访2~60个月,无失访病例,随访期间死亡56例,5年总体生存率为45.63%(47/103)。分别以miR-181a-5p、lncRNA CCAT1相对表达量的均数为临界值,将NSCLC患者分为miR-181a-5p低表达者50例与miR-181a-5p高表达者53例、lncRNA CCAT1低表达者54例与lncRNA CCAT1高表达者49例。miR-181a-5p低表达者5年总体生存率明显低于其高表达者,而lncRNA CCAT1低表达者5年总体生存率明显高于其高表达者(P均<0.05)。多因素Cox比例风险回归分析显示,临床分期Ⅲ、Ⅳ期及伴淋巴结转移、血清外泌体miR-181a-5p低表达、血清外泌体lncRNA CCAT1高表达是NSCLC患者预后不良的独立危险因素(P均<0.05)。结论NSCLC患者血清外泌体miR-181a-5p表达下调、lncRNA CCAT1表达上调,二者表达呈负相关关系且与肿瘤临床分期、淋巴结转移和患者预后密切相关。

Objective To study the expression changes of microRNA(miR)-181a-5p and long non-coding RNA(lncRNA)CCAT1 in serum exosomes of patients with non-small-cell lung cancer(NSCLC)and their relationships with clinicopathological features and prognosis of patients.Methods Totally 103 cases of NSCLC patients(observation group)and 27 healthy subjects(control group)were selected.The peripheral venous blood of the two groups was collected,and the serum was retained by centrifugation to extract the serum exosomes.The expression of miR-181a-5p and lncRNA CCAT1 in serum exosomes of the two groups were detected by real-time fluorescence quantitative PCR.The expression levels of serum exosomes miR-181a-5p and lncRNA CCAT1 were compared between the two groups.The relationships between the expression of serum exosomes miR-181a-5p and lncRNA CCAT1,and the relationship between their expression and clinicopathological features of patients with NSCLC were analyzed.Kaplan-Meier method was used to analyze the relationship between the expression of serum exosomes miR-181a-5p and lncRNA CCAT1 and the 5-year overall survival rate of NSCLC patients.Cox proportional hazards regression model was used to analyze the risk factors for poor prognosis of patients with NSCLC.Results The relative expression of miR-181a-5p in serum exosomes of the observation group was significantly lower than that in the control group,and the relative expression of lncRNA CCAT1 in serum exosomes was significantly higher than that in the control group(both P<0.01).Pearson correlation analysis showed that there was a negative correlation between the relative expression of miR-181a-5p and the relative expression of lncRNA CCAT1 in serum exosomes of patients with NSCLC(P<0.01).The expression levels of serum exosomes miR-181a-5p and lncRNA CCAT1 in patients with NSCLC were related to tumor clinical stage and lymph node metastasis(all P<0.05),but not to gender,age,smoking history,tumor diameter,pathological type,or degree of tissue differentiation(all P>0.05).Totally 103 patients with NSCLC were followed up for 2-60 months,and there were no lost cases;56 patients died during the follow-up period.The 5-year overall survival rate was 45.63%(47/103).Taking the average relative expression of serum exosomes miR-181a-5p and lncRNA CCAT1 as the critical value,NSCLC patients were divided into 50 cases of low expression of miR-181a-5,53 cases of high expression of miR-181a-5,54 cases of low expression of lncRNA CCAT1,and 49 cases of high expression of lncRNA CCAT1.The 5-year overall survival rate of patients with low expression of miR-181a-5 was significantly lower than that of patients with high expression,while the 5-year overall survival rate of patients with low expression of lncRNA CCAT1 was significantly higher than that of patients with high expression(all P<0.05).Multivariate Cox proportional hazards regression analysis showed that clinical stage Ⅲ and Ⅳ,lymph node metastasis,low expression of miR-181a-5p and high expression of lncRNA CCAT1 in serum exosomes were independent risk factors for poor prognosis of patients with NSCLC(all P<0.05).Conclusion The expression of miR-181a-5p in serum exosomes of NSCLC patients is down-regulated,and the expression of LncRNA CCAT1 is up-regulated,their expression is negatively correlated,and is closely related to the clinical stage,lymph node metastasis,and patients'prognosis.