[摘 要] 目的：探讨含溴结构域蛋白1（BRD1）通过调控PI3K/AKT信号通路影响非小细胞肺癌（NSCLC）进展的作用机制。 方法：利用TIMER 3.0数据库评估BRD1作为免疫治疗标志物的预测价值。利用慢病毒体系构建稳定过表达BRD1及N端截短突变体BRD1-ΔN的人肺癌细胞A549和NCI-H1299。采用CCK-8实验、克隆形成实验、划痕愈合实验及Transwell实验检测过表达BRD1/BRD1-ΔN对细胞增殖和迁移能力的影响；流式细胞术和Western blotting检测细胞凋亡水平及凋亡相关蛋白的变化。 RNA-seq筛选受BRD1/BRD1-ΔN影响的信号通路，Western blotting及体外激酶实验验证BRD1/BRD1-ΔN过表达对AKT磷酸化的调控作用。采用AKT抑制剂LY294002处理过表达BRD1/BRD1-ΔN的NCI-H1299细胞，结合功能实验（CCK-8实验、划痕愈合实验）明确过表达BRD1/BRD1-ΔN促进细胞的增殖和迁移是否依赖AKT活化。通过RNA-seq联合KEGG/GSEA分析、免疫共沉淀（Co-IP）、RT-qPCR，鉴定整合素α2（ITGA2）是促进AKT活化的关键分子；通过Co-IP、敲低ITGA2、Western blotting及功能实验明确ITGA2在BRD1调控AKT活化中的具体作用。结果：数据库分析显示，BRD1可作为NSCLC免疫治疗的中等预测标志物 （AUC = 0.625）。过表达BRD1/BRD1-ΔN显著增强了NSCLC细胞的增殖和迁移能力（P < 0.01或P < 0.001），但不影响细胞凋亡及凋亡相关蛋白的表达（均P > 0.05）；RNA-seq分析表明过表达BRD1/BRD1-ΔN主要富集于PI3K/AKT信号通路。Western blotting及体外激酶实验显示，BRD1/BRD1-ΔN过表达不影响AKT上游激酶（PDK1）的磷酸化，也不改变AKT的乙酰化修饰水平 （均P > 0.05）；AKT抑制剂LY294002处理过表达BRD1/BRD1-ΔN细胞，发现BRD1/BRD1-ΔN促细胞增殖和迁移的作用部分依赖AKT的活化；RT-qPCR及Western blotting证实，BRD1过表达可上调ITGA2的mRNA和蛋白水平，敲低ITGA2则可逆转BRD1诱导的AKT激活及细胞增殖和迁移能力的增强。结论：BRD1是NSCLC的一种新型促癌因子，其通过上调ITGA2表达激活AKT信号通路，进而促进肺癌细胞的增殖和迁移。

[Abstract] Objective: To investigate the role of bromodomain-containing protein 1 (BRD1) in the progression of non-small cell lung cancer (NSCLC) and its underlying mechanism through regulation of the PI3K/AKT signaling pathway. Methods: The predictive value of BRD1 as an immunotherapeutic biomarker was assessed using the TIMER 3.0 database. Human NSCLC cell lines A549 and NCI-H1299 stably overexpressing BRD1 or the N-terminal truncated mutant BRD1- ΔN were established using a lentiviral system. CCK-8, colony formation, wound healing, and Transwell assays were used to assess the effects of BRD1/BRD1-ΔN overexpression on cell proliferation and migration. Flow cytometry and Western blotting were used to detect cell apoptosis and the expression of apoptosis- related proteins. RNA-seq was employed to screen the signaling pathways affected by BRD1/BRD1- ΔN overexpression. Western blotting and in vitro kinase assays were used to detect the activation of AKT signaling pathways by overexpressing BRD1/BRD1-ΔN. To determine whether BRD1/BRD1-ΔN promotes cell proliferation and migration in an AKT-dependent manner, the AKT inhibitor · · 619 [[PAGE_INDEX=2 FILE=08b612ef-59ff-47e1-960e-f599d97bfff7.pdf]] 中国肿瘤生物治疗杂志, 2026, 33(6) LY294002 was applied to NCI-H1299 cells overexpressing BRD1/BRD1- ΔN, followed by functional assays (CCK-8 and wound healing). RNA-seq combined with KEGG/GSEA analysis, co-immunoprecipitation (Co-IP), and RT-qPCR were performed to identify and validate integrin alpha-2 (ITGA2) as a key mediator that facilitates AKT activation. Co-IP, lentivirus-mediated ITGA2 knockdown, Western blotting, and functional experiments were then used to clarify the specific role of ITGA2 in BRD1-mediated AKT activation. Results: Database analysis showed that BRD1 could serve as a moderate predictive biomarker for immunotherapy in NSCLC (AUC = 0.625). Overexpression of BRD1/BRD1- ΔN significantly enhanced the proliferation and migration of NSCLC cells (all P < 0.01) without affecting apoptosis or the expression of apoptosis-related proteins (all P > 0.05). RNA-seq analysis indicated that BRD1/BRD1- ΔN overexpression primarily resulted in enrichment of the PI3K/AKT signaling pathway. Western blotting and in vitro kinase assays demonstrated that BRD1/BRD1-ΔN overexpression did not affect the phosphorylation of PDK1, an upstream kinase of AKT, nor alter the acetylation level of AKT (all P > 0.05). Treatment with the AKT inhibitor LY294002 revealed that BRD1/BRD1-ΔN promoted cell proliferation and migration partially through AKT activation. RT-qPCR and Western blotting confirmed that BRD1 overexpression upregulated ITGA2 at both mRNA and protein levels. Silencing ITGA2 reversed BRD1-induced AKT activation and the enhanced cell proliferation and migration. Conclusion: BRD1 is a novel oncogenic driver in NSCLC. It activates the AKT signaling pathway by upregulating ITGA2, thereby promoting the proliferation and migration of lung cancer cells.

[基金项目] 河南省医学科学攻关计划（SBGJ202302092）；河南省重点研发与推广项目（262102310333）