This study aimed at investigating the crucial mechanisms underlying non-small cell lung cancer (NSCLC). NSCLC-related microarray data GSE27262 were downloaded from Gene Expression Omnibus, including 7 NSCLC 1a samples, 18 NSCLC 1b samples, and their matched normal samples. The common differentially expressed genes (DEGs) between NSCLC 1a and NSCLC 1b samples were identified, followed by protein-protein interaction (PPI) network construction, functional enrichment analysis, and weighted gene co-expression network analysis (WGCNA). Further, the key DEGs were confirmed based on the lung adenocarcinoma (LUAD) data from the Cancer Genome Atlas (TCGA) database, followed by clinical prognostic analysis. There were 802 (NSCLC 1a) and 734 (NSCLC 1b) DEGs identified. By intersection analysis, we obtained 255 upregulated and 97 downregulated common DEGs. Upregulated DEGs were significantly enriched in the plasma membrane and extracellular region, whereas the downregulated DEGs were significantly enriched in the cytoskeleton and cell cycle process. Topoisomerase (DNA) II alpha (TOP2A) and cyclin B1 (CCNB1) were hub nodes in the PPI network. Based on WGCNA, 5 modules were obtained. In the module MEgreen, DEGs were significantly enriched in cytokine-cytokine receptor interaction and focal adhesion. Notably, 1797 DEGs were identified based on the LUAD data from the TCGA database; among them, 285 DEGs were common DEGs identified from GSE27262 data. Upregulation of TOP2A and CCNB1 was correlated with poor survival of patients. The hub genes and key pathways identified in this study are helpful for a comprehensive knowledge of the molecular mechanisms of NSCLC.

中文翻译：

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与非小细胞肺癌相关的潜在机制的调查。

本研究旨在研究非小细胞肺癌 (NSCLC) 的关键机制。NSCLC相关微阵列数据GSE27262从Gene Expression Omnibus下载，包括7个NSCLC 1a样本、18个NSCLC 1b样本及其匹配的正常样本。确定了NSCLC 1a和NSCLC 1b样本之间的常见差异表达基因（DEG），然后进行蛋白质-蛋白质相互作用（PPI）网络构建、功能富集分析和加权基因共表达网络分析（WGCNA）。此外，根据癌症基因组图谱 (TCGA) 数据库中的肺腺癌 (LUAD) 数据确认了关键的 DEG，然后进行了临床预后分析。鉴定出 802 个（NSCLC 1a）和 734 个（NSCLC 1b）DEG。通过交叉分析，我们获得了 255 个上调和 97 个下调的常见 DEG。上调的DEGs在质膜和细胞外区域显着富集，而下调的DEGs在细胞骨架和细胞周期过程中显着富集。拓扑异构酶 (DNA) II α (TOP2A) 和细胞周期蛋白 B1 (CCNB1) 是 PPI 网络中的枢纽节点。基于WGCNA，获得了5个模块。在 MEgreen 模块中，DEG 在细胞因子-细胞因子受体相互作用和粘着斑方面显着富集。值得注意的是，基于 TCGA 数据库中的 LUAD 数据识别了 1797 个 DEG；其中，285个DEG是从GSE27262数据中识别出的常见DEG。TOP2A 和 CCNB1 的上调与患者的不良生存相关。本研究鉴定的枢纽基因和关键通路有助于全面了解NSCLC的分子机制。