Department of Respiratory and Critical Care Medicine, Xuzhou Hospital Affiliated to Xuzhou Medical University, Xuzhou Central Hospital, Xuzhou, China.
Department of Respiratory and Critical Care Medicine, The Xuzhou School of Clinical Medicine of Nanjing Medical University, Xuzhou, China.
J Investig Med. 2024 Jan;72(1):57-66. doi: 10.1177/10815589231207801. Epub 2023 Dec 12.
This study intended to delineate the mechanism and functional role of integrin α2 (ITGA2) in non-small-cell lung cancer (NSCLC) cell immune escape. Bioinformatics analysis was utilized to analyze ITGA2 expression in NSCLC tissues, and correlations between ITGA2 expression and patient survival time, ITGA2 expression and programmed cell death ligand 1 (PD-L1; CD274) expression, and ITGA2 expression and CD8+ T-cell infiltration. Quantitative real-time polymerase chain reaction detected ITGA2 expression. Transmission electron microscopy was applied to examine the morphology of exosomes, and western blot measured CD9, CD63, and PD-L1 levels. CCK-8 measured cell viability. Cell toxicity experiment measured the killing effect of CD8+ T cells on cancer cells. Enzyme-linked immunosorbent assay assessed secretion levels of interleukin-2, interferon-gamma, tumor necrosis factor-alpha, and PD-L1 expression in exosomes. Immunohistochemistry detected ITGA2, CD8, and PD-L1 expression in patient tissue samples. ITGA2 was highly expressed in NSCLC, and Pearson correlation analysis showed a negative correlation of ITGA2 with CD8+ T-cell infiltration and a positive correlation of ITGA2 with PD-L1 expression. Cell experiments showed that silencing ITGA2 hindered NSCLC cell progression and increased levels of CD8+ T-cell secretory factors. Further mechanism studies found that ITGA2 reduced CD8+ T-cell-mediated antitumor immunity via the increase in PD-L1 expression. Clinical sample testing unveiled that ITGA2 was upregulated in NSCLC tissues. PD-L1 upregulation was seen in exosomes separated from patient blood, and correlation analysis showed a positive correlation of exosomal PD-L1 expression in blood with ITGA2 expression in tissues. This study displays a novel mechanism and role of ITGA2 in NSCLC immune escape, providing directions for the clinical therapy of NSCLC patients.
本研究旨在描绘整合素α2（ITGA2）在非小细胞肺癌（NSCLC）细胞免疫逃逸中的机制和功能作用。利用生物信息学分析方法分析 NSCLC 组织中 ITGA2 的表达，以及 ITGA2 表达与患者生存时间、ITGA2 表达与程序性死亡配体 1（PD-L1；CD274）表达、ITGA2 表达与 CD8+T 细胞浸润的相关性。采用实时定量聚合酶链反应检测 ITGA2 的表达。透射电子显微镜用于观察外泌体的形态，Western blot 检测 CD9、CD63 和 PD-L1 水平。CCK-8 检测细胞活力。细胞毒性实验检测 CD8+T 细胞对癌细胞的杀伤作用。酶联免疫吸附试验评估外泌体中白细胞介素-2、干扰素-γ、肿瘤坏死因子-α和 PD-L1 表达的分泌水平。免疫组织化学检测患者组织样本中 ITGA2、CD8 和 PD-L1 的表达。ITGA2 在 NSCLC 中高表达，Pearson 相关性分析显示 ITGA2 与 CD8+T 细胞浸润呈负相关，与 PD-L1 表达呈正相关。细胞实验表明，沉默 ITGA2 可阻碍 NSCLC 细胞的进展并增加 CD8+T 细胞分泌因子的水平。进一步的机制研究发现，ITGA2 通过增加 PD-L1 的表达来降低 CD8+T 细胞介导的抗肿瘤免疫。临床样本检测显示，ITGA2 在 NSCLC 组织中上调。从患者血液中分离的外泌体中观察到 PD-L1 的上调，相关性分析显示血液中外泌体 PD-L1 的表达与组织中 ITGA2 的表达呈正相关。本研究揭示了 ITGA2 在 NSCLC 免疫逃逸中的新机制和作用，为 NSCLC 患者的临床治疗提供了方向。
