| 摘要: |
| 目的 探讨非小细胞肺癌（NSCLC）免疫检查点分子程序性死亡配体1（PD-L1）的表达及其与miRNA-200家族之间的调控关系，阐明PD-L1在NSCLC中的临床意义及调控机制。方法 选取138例NSCLC患者癌组织及配对的癌旁组织标本，采用免疫组织化学染色检测PD-L1表达，qRT-PCR检测miRNA-200家族（miRNA-200a、miRNA-200b、miRNA-200c、miRNA-429、miRNA-141）的表达水平。培养肺癌A549细胞，通过转染miRNA-200家族5个miRNA模拟物使其过表达，采用蛋白质印迹法检测miRNA-200家族过表达对PD-L1表达的影响，CCK-8实验检测miRNA-200家族过表达对A549细胞增殖活性的影响，荧光素酶报告基因实验验证miRNA-200家族对PD-L1的调控作用。结果 138例NSCLC患者癌组织PD-L1总阳性率为58.7%（81/138），高于癌旁组织（3.6%，5/138），差异有统计学意义（P<0.05）；PD-L1表达水平与患者性别、年龄、肿瘤大小、组织学类型无关，而与淋巴结转移、脉管侵犯、临床TNM分期有关（P均<0.05）。NSCLC癌组织中miRNA-200家族表达水平均低于癌旁组织（P均<0.01），且PD-L1表达阳性的患者具有更低水平的miRNA-200家族表达水平（P均<0.01）。A549细胞过表达miRNA-200家族能下调PD-L1的表达（P均<0.01），且抑制癌细胞增殖活性（P均<0.01）。荧光素酶报告基因实验证实miRNA-200家族直接负调控PD-L1的表达（P均<0.01）。结论 PD-L1高表达预示NSCLC患者预后不良。PD-L1是miRNA-200家族的靶基因，miRNA-200家族表达水平低可能是NSCLC患者高表达PD-L1的重要原因。 |
| 关键词: 非小细胞肺癌 微RNA-200家族 程序性死亡配体1 分子调控机制 免疫治疗 |
| DOI：10.16781/j.0258-879x.2020.07.0780 |
| 投稿时间：2020-05-12修订日期：2020-06-22 |
| 基金项目:国家自然科学基金（81771767，81801580）. |
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| Regulation of programmed death ligand 1 by microRNA-200 family and its clinical significance in non-small cell lung cancer |
| SUN Wei1,BAI Zong-ke2,JIANG Li-hua3,SHAO Xiao-yi1* |
(1. Department of Immunology, School of Medicine, Nantong University, Nantong 226000, Jiangsu, China;
2. School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, Jiangsu, China;
3. Department of Medical Equipment, Eastern Hepatobiliary Surgery Hospital, Naval Medical University(Second Military Medical University), Shanghai 201805, China
*Corresponding author) |
| Abstract: |
| Objective To investigate the expression of the immune checkpoint molecule programmed death ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) and its regulatory relationship with the microRNA-200 (miRNA-200) family, and to elucidate the clinical significance and regulatory mechanism of PD-L1 in NSCLC. Methods NSCLC cancer tissues and matched paracancerous tissues (138 cases) were selected for this study. The PD-L1 expression was detected by immunohistochemistry and the expression levels of miRNA-200 family (miRNA-200a, miRNA-200b, miRNA-200c, miRNA-429, and miRNA-141) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Lung cancer A549 cells were cultured and transfected with five miRNA mimics of miRNA-200 family. The effect of miRNA-200 family mimics on PD-L1 expression and proliferation activity of A549 cells were detected by Western blotting and cell counting kit-8 (CCK-8) assay, respectively. Luciferase reporter gene assay was used to elucidate the regulation of PD-L1 by miRNA-200 family. Results Total positive rate of PD-L1 in 138 NSCLC tissues was 58.7% (81/138), which was significantly higher than that in paracancerous tissues (3.6%, 5/138) (P<0.05). The expression level of PD-L1 was not related to the patients' gender, age, tumor size or histological types, but was closely related to lymph node metastasis, vascular invasion and clinical TNM stage (all P<0.05). The miRNA-200 family was expressed at a low level in NSCLC tissues than that in paracancerous tissues (all P<0.01), and patients with positive PD-L1 expression had significantly lower levels of miRNA-200 family expression (all P<0.01). Overexpression of miRNA-200 family in A549 cells significantly down-regulated PD-L1 and inhibited proliferation activity of cancer cells (all P<0.01). Luciferase reporter gene assay confirmed that the miRNA-200 family directly and negatively regulated the expression of PD-L1 (all P<0.01). Conclusion High expression of PD-L1 in NSCLC indicates poor prognosis. PD-L1 is the target gene of miRNA-200 family, and the low expression of miRNA-200 family may be an important reason for the high expression of PD-L1 in NSCLC. |
| Key words: non-small cell lung cancer microRNA-200 family programmed death ligand 1 molecular regulatory mechanism immunotherapy |
