血清外泌体Glypican-1在乳腺癌中的表达水平及临床应用价值

Expression level and clinical application value of human serum exosomal Glypican-1 in breast cancer

目的探讨乳腺癌血清外泌体Glypican-1(GPC-1)的表达水平及其临床应用价值。方法选择河北医科大学第四医院确诊的乳腺癌48例和乳腺良性占位18例,同期健康体检者17名作为健康对照组;采用聚乙二醇8000沉淀法提取血清外泌体,使用透射电镜和蛋白印迹对外泌体形态和分子表型进行鉴定;Western blot检测各组血清外泌体GPC-1表达水平;采用受试者工作特征(receiver operating characteristic,ROC)曲线评价血清外泌体GPC-1对乳腺癌的诊断效能;以最佳截断值0.961将乳腺癌组分为GPC-1阳性组和GPC-1阴性组,分析其与临床特征的关系;采用Wilcoxon秩和检验分析乳腺癌组治疗前后血清外泌体GPC-1表达变化;以病理诊断为金标准,采用Kappa一致性检验评价血清外泌体GPC-1、血清肿瘤标志物、超声、钼靶射线四种诊断方法对乳腺癌的诊断价值。结果乳腺癌组血清外泌体GPC-1表达水平[1.065(0.501)]高于乳腺良性占位组[0.652(0.117)]和健康对照组[0.625(0.139)],差异有统计学意义(H=32.051,P<0.05);ROC曲线下面积为0.900(95%CI:0.833~0.967),最佳截断值0.961,能够有效筛查乳腺癌患者;乳腺癌组中GPC-1阳性在不同TNM分期、淋巴结浸润和Ki-67高表达组间差异有统计学意义(P均<0.05);乳腺癌组治疗前血清外泌体GPC-1表达水平[1.065(0.501)]高于治疗20 d后血清外泌体GPC-1表达水平[0.844(0.195)],差异有统计学意义(Z=856.0,P=0.006);血清外泌体GPC-1检测方法的Kappa值为0.485>0.4,与病理检查比较一致性中等,且优于其他三种检测方法。结论乳腺癌组血清外泌体GPC-1表达上调,且与多个不良临床特征相关,并在治疗后显著下降,具备作为乳腺癌诊断和治疗效果评价指标的潜力。

Objective To explore the expression level of serum exosomal Glypican-1(GPC-1)in patients with breast cancer and its clinical application value.Methods A total of 48 patients diagnosed with breast cancer,and 18 patients diagnosed with benign breast mass in the Fourth Hospital of Hebei Medical University were selected.Another 17 healthy subjects undergoing physical examination during the same period were selected as healthy control group.Serum exosomes were extracted by polyethylene glycol 8000 precipitation method,and the morphology and molecular phenotype of exosomes were identified by transmission electron microscopy and western blotting.Western blotting was used to detect the expression level of serum exosomal GPC-1 in each group.Receiver operating characteristic(ROC)curve was used to evaluate the diagnostic efficacy of serum exosomal GPC-1 for breast cancer.With the best cut-off value of 0.961,the breast cancer group was divided into GPC-1 positive group and GPC-1 negative group,to analyze the relationship between GPC-1 and clinical characteristics.The Wilcoxon rank sum test was used to analyze the changes of serum exosomal GPC-1 expression in breast cancer group before and after treatment.Taking pathological diagnosis as the gold standard,Kappa consistency test was used to evaluate the diagnostic value of four diagnostic methods,serum exosomal GPC-1,serum tumor markers,B-ultrasound,and mammography,for breast cancer.Results The expression level of serum exosomal GPC-1 in the breast cancer group[1.065(0.501)]was higher than that of the benign breast mass group[0.652(0.117)]and the healthy control group[0.625(0.139)],and the difference was statistically significant(H=32.051,P<0.05).The area under the ROC curve(AUC)was 0.900(95%CI:0.833-0.967),and the optimal cut-off value was 0.961,which could be used to effectively screen breast cancer patients.GPC-1 positivity in breast cancer group was significantly correlated with TNM stage,lymph node invasion and Ki-67 high expression(all P<0.05).The expression level of serum exosomal GPC-1 in the breast cancer group before treatment[1.065(0.501)]was higher than that at 20 d after treatment[0.844(0.195)],and the difference was statistically significant.The Kappa value of the serum exosomal GPC-1 detection method was 0.485>0.4,which was moderately consistent with pathological examination and was superior to the other three detection methods.Conclusion The expression of serum exosomal GPC-1 in the breast cancer group is up-regulated,which is associated with multiple adverse clinical characteristics,and significantly decreases after treatment.Therefore,it has the potential to be used as an index for the diagnosis and treatment of breast cancer.