Inhibitory effect of sinomenine on lung cancer cells via negative regulation of α7 nicotinic acetylcholine receptor
Inhibitory effect of sinomenine on lung cancer cells via negative regulation of α7 nicotinic acetylcholine receptor
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青藤碱负调控α7烟碱乙酰胆碱受体对肺癌细胞的抑制作用
DOI：
10.1002/jlb.6ma0720-344rrr
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发表时间：
2020-07-29
影响因子：
5.5
通讯作者：
Dong, Yan
中科院分区：
文献类型：
--
作者：
Bai, Shasha;Wen, Wenhao;Dong, Yan
肺癌是全世界癌症死亡的主要原因，发病率高，存活率不到20%。因此，需要新的治疗策略和药物来降低肺癌患者的死亡率。α 7烟碱乙酰胆碱受体（α 7 nAChR）作为尼古丁及其代谢物的受体，是肺癌治疗的潜在靶点。我们前期研究发现青藤碱通过α 7 nAChR发挥抗炎作用，下调该受体的表达，从而增加炎症反应。因此，青藤碱可能是该受体的天然配体。本研究通过测定青藤碱对肺癌A549细胞及荷瘤小鼠的影响，探讨青藤碱是否通过α 7 nAChR对肺癌有抑制作用。分别采用CCK-8法、创面愈合法和流式细胞术进行体外细胞增殖、细胞迁移和细胞凋亡分析。采用异种移植小鼠对青藤碱的体内作用进行了评价。结果表明青藤碱降低了细胞的增殖和迁移能力，但增加了凋亡细胞的比例。青藤碱处理后荷瘤小鼠的肿瘤体积明显小于对照组（p < 0.05）。此外，青叶碱的作用被α - 7 nAChR拮抗剂甲胺和变构调节剂PNU-120596所消除，而毒蕈碱乙酰胆碱受体拮抗剂阿托品预处理后，青叶碱的作用没有发生变化。同时青叶碱在体外和体内抑制α 7 nAChR的表达，以及相关信号分子pERK1/2、ERK1/2和转录因子TTF-1、SP-1的表达。相比之下，青藤碱上调了另一种转录因子Egr-1的表达。甲美胺和PNU限制了这些作用，但阿托品没有。结果提示青藤碱可通过α 7 nAChR负反馈抑制肺癌。
Lung cancer is the leading cause of cancer deaths worldwide, with a high morbidity and less than 20% survival rate. Therefore, new treatment strategies and drugs are needed to reduce the mortality of patients with lung cancer. alpha 7 nicotinic acetylcholine receptor (alpha 7 nAChR), as a receptor of nicotine and its metabolites, is a potential target for lung cancer treatment. Our previous studies revealed that sinomenine plays anti-inflammation roles via alpha 7 nAChR and down-regulates the expression of this receptor, thus increasing the inflammatory response. Hence, sinomenine is possibly a natural ligand of this receptor. In the present study, the effects of sinomenine on lung cancer A549 cells and tumor-bearing mice were determined to investigate whether this alkaloid has an inhibitory effect on lung cancer via alpha 7 nAChR. CCK-8 assay, wound-healing test, and flow cytometry were performed for cell proliferation, cell migration, and apoptosis analysis in vitro, respectively. Xenograft mice were used to evaluate the effects of sinomenine in vivo. Results showed that sinomenine decreased cell proliferation and migration abilities but increased the percentage of apoptotic cells. Tumor volume in tumor-bearing mice was significantly reduced after sinomenine treatment compared with that in the vehicle group mice (p < 0.05). Furthermore, the effects of sinomenine were abolished by the alpha 7 nAChR antagonist mecamylamine and the allosteric modulator PNU-120596, but no change occurred when the mice were pretreated with the muscarinic acetylcholine receptor antagonist atropine. Meanwhile, sinomenine suppressed alpha 7 nAChR expression in vitro and in vivo, as well as the related signaling molecules pERK1/2 and ERK1/2 and the transcription factors TTF-1 and SP-1. By contrast, sinomenine up-regulated the expression of another transcription factor, Egr-1. These effects were restricted by mecamylamine and PNU but not by atropine. Results suggested that sinomenine can inhibit lung cancer via alpha 7 nAChR in a negative feedback mode.