摘要目的:探究NPAS2基因在肺腺癌(LUAD)中的表达及其与相关临床参数的关联，分析其对患者总生存期(OS)的影响及在LUAD预后中的预测价值。方法:从癌症基因组图谱数据库(TCGA)中下载LUAD转录组测序及临床资料数据，分析LUAD肿瘤组织与正常肺组织中NPAS2的表达差异。收集LUAD患者肿瘤组织及正常肺组织应用蛋白免疫印迹法(WB)检测NPAS2蛋白表达，并分析TCGA数据库中NPAS2表达与LUAD患者肿瘤分期及OS的关联。通过基因集富集分析(GSEA)挖掘NPAS2潜在的致癌机制。结果:TCGA差异分析显示NPAS2 mRNA在LUAD肿瘤组织1.83(1.01，3.01)中的表达水平高于正常肺组织，0.74(0.49，1.15)，差异有统计学意义( Z＝7.21， P<0.05)；配对分析显示NPAS2 mRNA在LUAD组织1.82(1.37，3.08)中的表达也高于配对的正常肺组织0.76(0.51，1.16)，差异有统计学意义( Z＝5.63， P<0.05)。WB结果显示，NPAS2蛋白在LUAD 0.62(0.40，1.36)中的表达水平高于正常肺组织0.14(0.08，0.58)，差异有统计学意义( Z＝2.71， P<0.05)。在亚组分析中，与T1~2组相比，T3~4组中NPAS2 mRNA高表达的比例更高1.81(1.01，2.92)比2.10(1.29，3.71)( Z＝2.12， P<0.05)；在预后分析中，NPAS2高表达组患者的预后相对较差，与NPAS2 mRNA低表达组比较差异有统计学意义( χ2＝9.66， P<0.05)，Kaplan-Meier plotter数据库显示NPAS2 mRNA高表达LUAD患者预后更差( HR＝2.19， P<0.05)，Cox比例风险模型进行多因素分析表明更高的TNM分期( HR＝2.12， P<0.05)及NPAS2 mRNA高表达( HR＝1.21， P<0.05)预后更差，与NPAS2低表达患者相比，NPAS2高表达患者OS更短( P<0.05)；GSEA基因富集结果显示NPAS2高表达时，肿瘤、小细胞肺癌、细胞外基质受体相互作用、凋亡、白细胞跨内皮迁移、ERBB等通路相关基因显著富集。 结论:NPAS2在LUAD中高表达，并与肿瘤局部浸润和OS相关，可以作为LUAD独立的预后预测因子。

abstractsObjective:To measure the expression level of NPAS2 in lung adenocarcinomas (LUAD) and to explore its potential in predicting the overall survival (OS) and prognosis of LUAD.Methods:Transcriptome sequencing and clinical data of LUAD were downloaded from The Cancer Genome Atlas (TCGA)to detect the differential expressions of NPAS2 in LUAD specimens and normal lung tissues.Expression levels of NPAS2 in LUAD specimens and normal lung tissues we collected by detected by Western blot(WB). The correlation between NPAS2 expression and tumor staging and OS of LUAD patients was identified.The enriched pathways in NPAS2 were predicted by the gene set enrichment analysis (GSEA).Results:TCGA data showed that the mRNA level of NPAS2 in LUAD specimens was significantly higher than that of normal lung tissues (1.83 [1.01, 3.01] vs 0.74[0.49, 1.15], Z=7.21, P<0.05). Matched analysis revealed that the mRNA level of NPAS2 in LUAD specimens was also significantly higher than that of paired normal lung tissues (1.82[1.37, 3.08] vs 0.76[0.507, 1.156], Z=5.63, P<0.05). WB analysis verified the protein level of NPAS2 in LUAD specimens was significantly upregulated than that of normal lung tissues (0.62[0.40, 1.36] vs 0.14[0.08, 0.58], Z=2.71, P<0.05). Subgroup analysis suggested that the proportion of LUAD patients overexpressing NPAS2 was significantly higher in those with tumor staging 3-4 (T3-4) 2.10(1.29, 3.71) than those of T1-2 1.81(1.01, 2.92)( Z=2.12, P<0.05). Prognostic analysis evidenced that LUAD patients with high expression levels of NPAS2 had a significantly worse prognosis compared with those expressing low levels of NPAS2 ( χ2=9.66, P<0.05). Kaplan-Meier survival analysis showed a worse prognosis in LUAD patients overexpressing NPAS2 ( HR=2.19, P<0.05). Consistently, Cox proportional hazards model showed that LUAD patients with more advanced TNM staging ( HR=2.12, P<0.05) and higher expression levels of NPAS2 ( HR=1.21, P<0.05) had a shorter OS.GSEA results revealed that cancer, small cell lung cancer, extracellular matrix receptor interaction, apoptosis, leukocyte transendothelial migration and ERBB signaling pathways were mainly enriched in NPAS2. Conclusions:NPAS2 is highly expressed in LUAD and correlated with local tumor invasion and OS, serving as an independent prognostic predictor of LUAD.