探讨早期肺腺癌(lung adenocarcinoma, LUAD)患者血清外泌体miRNA表达谱特征，筛选具有早期诊断价值的微小RNA(microRNA, miRNA)生物标志物。

招募2021年1月至2024年12月受试者255例，I期LUAD患者154例为LUAD组、良性肺结节(benign pulmonary nodules, BPN)患者101例为BPN组。随机分为发现队列、筛查队列、验证队列。采用miRNA测序，与GES137140数据集中差异表达miRNA进行比较，筛选miRNA。通过定量逆转录聚合酶链反应(quantitative reverse transcription-polymerase chain reaction, qRT-PCR)验证差异表达miRNA。使用受试者工作特征曲线(receiver operating characteristic, ROC)判断候选miRNA诊断性能，通过生物信息学分析预测靶基因和相关信号通路。

血清外泌体平均粒径70.0 nm，浓度3.66×10⁸个/ml。发现队列中2组间存在38个重叠DEmiR，包括10个上调DEmiRs和28个下调DEmiRs。与GES137140数据集交叉分析，筛选出7种DEmiR，包括hsa-miR-486-5p、hsa-miR-346、hsa-miR-130b-3p、hsa-miR-183-5p、hsa-miR-18a-3p、hsa-miR-625-5p、hsa-miR-25-3p。筛选队列和验证队列中与对照组和BPN组相比，LUAD组外泌体miR-486-5p、miR-346上调，外泌体miR-130b-3p下调(P<0.05)。miR-486-5p、hsa-miR-346、miR-130b-3p诊断早期LUAD的曲线下面积(area under the curve, AUC)>0.7，敏感度分别为76.00%、88.0%、92.80%，特异度分别为82.86%、59.43%、61.32%。miRNA联合检测AUC为0.956(95%CI：0.921~0.979)，敏感度和特异度达88.0%和90.48%。3种miRNA联合肿瘤标志物诊断AUC可达0.969(95%CI：0.949~0.989)。4种工具分别发现对miR-486-5p、miR-346、miR-130b-3p上280、650和26个靶基因。KEGG分析中JNK信号通路和整合素等术语在血管生成和其他生物学途径中得到富集。

血清外泌体miR-486-5p、miR-346和miR-130b-3p组成的miRNA特征谱在早期LUAD检测中具有良好的诊断性能，可作为早期LUAD的诊断标志物。

To investigate the characteristics of the serum exosomal miRNA expression profile in patients with early-stage lung adenocarcinoma (LUAD) and to screen for microRNA (miRNA) biomarkers with value for early diagnosis.

A total of 255 subjects were enrolled from January 2021 to December 2024, including 154 patients with stage Ⅰ LUAD as the LUAD group, 101 patients with benign pulmonary nodules (BPN) as the BPN group, It was randomly divided into the discovery cohort, the screening cohort and the verification cohort. miRNA sequencing was performed, and differentially expressed miRNAs were screened by comparing them with those in the GES137140 dataset. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to validate the differentially expressed miRNAs. The diagnostic performance of candidate miRNAs was evaluated using receiver operating characteristic (ROC) curves, and target genes and related signaling pathways were predicted through bioinformatics analysis.

The average particle size of serum exosomes was 70.0 nm, with a concentration of 3.66×10⁸ particles/ml. In the discovery cohort, 38 overlapping DEmiRs were identified among the two groups, including 10 upregulated and 28 downregulated DEmiRs. Cross-analysis with the GES137140 dataset screened out seven DEmiRs: hsa-miR-486-5p, hsa-miR-346, hsa-miR-130b-3p, hsa-miR-183-5p, hsa-miR-18a-3p, hsa-miR-625-5p, and hsa-miR-25-3p. In both the screening and validation cohorts, compared with the control and BPN groups, exosomal miR-486-5p and miR-346 were upregulated, and exosomal miR-130b-3p was downregulated in the LUAD group (P<0.05). The area under the curve (AUC) for diagnosing early LUAD was >0.7 for miR-486-5p, hsa-miR-346, and miR-130b-3p, with sensitivities of 76.00%, 88.0%, and 92.80%, and specificities of 82.86%, 59.43%, and 61.32%, respectively. The combined detection of miRNAs yielded an AUC of 0.956 (95%CI: 0.921~0.979), with a sensitivity and specificity of 88.0% and 90.48%. The combination of these three miRNAs with tumor markers achieved an AUC of 0.969 (95%CI: 0.949~0.989). Four tools identified 280, 650, and 26 target genes for miR-486-5p, miR-346, and miR-130b-3p, respectively. KEGG analysis showed enrichment of terms such as the JNK signaling pathway and integrins in angiogenesis and other biological processes.

The miRNA signature composed of serum exosomal miR-486-5p, miR-346, and miR-130b-3p demonstrates good diagnostic efficacy for detecting early LUAD and shows promise as a diagnostic marker for early LUAD.