目的 探讨miRNA⁃221（miR⁃221）在非小细胞肺癌（NSCLC）患者血浆外泌体中的表达水平及其 诊断价值。方法 选取2018年12月 至2019年12月来湖北省十堰市国药东风总医院就诊的72例NSCLC患 者为肺癌组，选取同期体检健康人群52例为对照组。全血离心后采用试剂盒分别提取血浆外泌体及其RNA， 通过透射电子显微镜、蛋白印迹技术及纳米粒径技术对血浆外泌体进行鉴定。采用实时定量聚合酶链反应检 测miR⁃221在肺癌组和对照组中的表达水平，比较分析其与肺癌患者临床病理参数关系。选择受试者工作特 征曲线（ROC）分析血浆外泌体miR⁃221对NSCLC的诊断价值。结果 成功分离了血浆外泌体，并进行了鉴定 符合公认的外泌体特征。NSCLC 组血浆外泌体miR⁃221 的表达水平显著高于健康对照组，差异有统计学意义 （P < 0.001）。ROC 曲线下面积（AUC）为0.758（95% CI：0.672 ~ 0.844，P < 0.001），敏感度为 86%，特异度为66%。 结论 血浆外泌体miR⁃221可作为诊断NSCLC的潜在生物学标志物，对NSCLC的临床诊断具有辅助价值。

Objective To explore the expression level and diagnostic value of plasma exosomal miR⁃221 for non⁃small cell lung cancer（NSCLC）. Methods Sera of 72 NSCLC patients（NSCLC group）and 52 healthy controls（healthygroup），there are from December 2018 to December 2019，Dongfeng General Hospital of Sino⁃ pharm，Hubei Shiyan. After centrifugation of whole blood，the exosomes and their RNA were extracted by kit， identification of plasma exosomal by transmission electron microscopy，Western blotting and nanoparticle tracking analysis. The expression of miR⁃221 in lung cancer group and control group was detected by real⁃time quantitative polymerase chain reaction，a comparative analysis of the relationship between them and clinicopathological parame⁃ ters of lung cancer patients. The diagnostic value of exosomal miR⁃221 was evaluated with receiver operating charac⁃ teristic（ROC）curve. Results The plasma exosomes were successfully isolated and identified according to the recognized exosomes characteristics. The expression of miR⁃221 was significantly higher in the NSCLC group than in the healthy control group（P < 0.001）. The area under the ROC curve（AUC）was 0.758（95% CI：0.672～0.844， P < 0.001）. The diagnostic sensitivity was 86%，and the specificity was 66%. Conclusion Plasma exosomal miR⁃ 221 may be a potential biomarker for diagnosis of NSCLC，