摘要
目的明确前列腺素E2(PGE2)在肺癌脑转移过程中的作用,并探讨阿司匹林(PGE2抑制剂)降低肺癌脑转移的可能机制。方法体外细胞培养,放射免疫法测定给予阿司匹林(8mmol/L)后不同时间点肺癌细胞培养液中PGE2质量浓度的变化;将肺癌细胞和阿司匹林(8mmol/L)加入Transwell构建的体外血脑屏障模型上室后,Western blot法动态检测脑微血管内皮细胞内occludin蛋白的表达水平;通过辣根过氧化物酶检测体外血脑屏障模型的通透性改变,Hemocytometer法计数通过体外血脑屏障模型的肺癌细胞数。建立肺癌脑转移动物模型,观察阿司匹林对裸小鼠肺癌脑转移发生率的影响。结果在细胞水平上研究发现,给予阿司匹林后,肺癌细胞培养液内PGE2质量浓度降低,于阿司匹林作用120min时降至最低。模型中脑微血管内皮细胞occludin蛋白的表达于阿司匹林作用后增加,且于阿司匹林作用120min时增加程度最大。与此同时,模型中血脑屏障通透性和肺癌细胞透过血脑屏障的数量亦于给予阿司匹林120min时降至最低值。动物模型观察发现,阿司匹林可以明显降低肺癌脑转移的发生率(P<0.05)。结论阿司匹林可以降低肺癌脑转移的发生,其作用机制可能为阿司匹林抑制肺癌细胞释放PGE2,进而上调紧密连接蛋白occludin的表达,从而降低了血脑屏障的通透性。
Objective To determine the effect of prostaglandin E2 （PGE2） on brain metastasis of lung cancer, and to explore the possible mechanism of aspirin （PGE2 inhibitor） reducing brain metastasis of lung cancer. Methods Radioimmunoassay was performed to measure the expression level of PGE2 in cell supernatant collected from cells treated with or without aspirin （8 mmol/L） at different time points. After establishing in vitro blood-brain barrier （BBB） model using Transwell, lung cancer cells was added to upper chamber of transwell and was then treated with aspirin （8 mmol/L）. Western blot was used to examine the expression of occludin protein in brain microvascular endothelial cells. The permeability changes of BBB model in vitro were determined using horseradish peroxides. The number of lung cancer cells passing through BBB model in vitro was counted with Hemocytometer. Effect of aspirin on brain metastasis of lung cancer was observed in nude mice in the animal level. Results PGE2 level decreased and reached minimum level 120 min after aspirin treatment in lung cancer cells culture fluid. Occludin expression increased and reached maximum level 120 min after aspirin treatment in brain microvascular endothelial cells. At the same time, permeability of BBB and number of lung cancer cells passing through BBB also reached the lowest value 120 min after aspirin treatment. Aspirin significantly reduced the incidence of brain metastasis of lung cancer in animal model. Conclusion Aspirin reduced occurrences of the brain metastasis of lung cancer in animal model, which may be caused by inhibition of PGE2 released by lung cancer cells and upregulation of occludin expression therefore leading to decrease in BBB permeability.
出处
《四川大学学报（医学版）》
CAS
CSCD
北大核心
2017年第6期857-861,共5页
Journal of Sichuan University(Medical Sciences)
基金
国家自然科学基金(No.81101912)
河北省高等学校科学技术研究项目(No.ZD20160082)
河北省中医药管理局中医药类科研项目(No.2014195)
河北省卫生厅科学研究基金项目(No.20170901)资助
