循环肿瘤细胞和外泌体miR-21检测在肺磨玻璃样病变诊断中的应用

Application of detection of circulating tumor cells and exosome miR-21 in diagnosis of lung ground glass opacity

目的:评价循环肿瘤细胞(CTC)联合外泌体miR-21检测方法用于肺磨玻璃样病变(GGO)临床诊断的实用性和可行性,为GGO的诊断提供依据。方法:按照GGO诊断标准和排除标准筛选出70例患者,均进行胸腔镜下肺段切除,术后病理诊断为肺癌的患者为病例组(n=24),术后病理诊断为良性病变的患者为对照组(n=46)。术前所有患者通过免疫磁珠负向富集方法从外周血中捕获CTC,采用肿瘤特异性叶酸配体-寡核苷酸偶合物标记捕获的CTC,同时检测同一标本的外泌体,纯化鉴定外泌体,检测患者血清外泌体miR-21表达水平。利用受试者工作特征(ROC)曲线评价CTC和外泌体miR-21对GGO患者的诊断效能。结果:病例组患者CTC阳性率高于对照组(P<0.05)。病例组和对照组不同病理类型患者CTC阳性率比较差异无统计学意义(P>0.05)。纯化样品具备外泌体特征。病例组患者血清外泌体miR-21表达水平高于对照组(P<0.05)。CTC的ROC曲线下面积(AUC)为0.891,外泌体miR-21的AUC为0.711,均具有较好的特异性。二者联合检测的灵敏度和特异度分别为85.64%和86.79%。结论:CTC结合外泌体miR-21检测可以应用于早期肺癌的临床诊断,其灵敏度和特异度较高。

Objective:To evaluate the practicability and feasibility of detection of circulating tumor cells(CTC)combined with exosome miR-21 in the diagnosis of ground glass opacity(GGO),and to provide the evidence for the diagnosis of GGO.Methods:Seventy patients were selected according to the diagnostic and exclusion criteria of GGO.All the patients underwent thoracoscopic segmentectomy.The patients diagnosed as lung cancer after operation were regarded as case group(n=24),and the patients diagnosed as benign lesion after operation were regarded as control group(n=46).Before operation,CTC was captured from the peripheral blood by negative enrichment of immunomagnetic beads.CTC was labeled with tumor-specific folate ligand-oligonucleotide conjugate.The exosomes of the same specimen were detected,purified and identified,and the expression levels of serum exosome miR-21 of the patients in two groups were detected.The diagnostic efficacies of CTC and exosome miR-21 in the GGO paitents were evaluated by ROC curves.Results:The positive rate of CTC in the patients in case group was higher than that in control group(P<0.05).There were no significant differences in the positive rates of CTC between the patients with different pathological types in case group and control group(P>0.05).The purified samples showed exosome characteristics.The expression level of serum exosome miR-21 in the patients in case group was higher than that in control group(P<0.05).The area under ROC curve(AUC)of CTC was 0.891,and the AUC of exosome miR-21 was 0.711,which showed good specificity.The sensitivity and specificity of the combined detection were 85.64% and 86.79%,respectively.Conclusion:The detection of CTC combined with exosome miR-21 can be used in the clinical diagnosis of early lung cancer with high sensitivity and specificity.