塞来昔布联合依维莫司对恶性嗜铬细胞瘤裸鼠移植瘤的抑制作用

The inhibitory effect of everolimus and celecoxib on the implanted rat malignant pheochromocytoma nude mice

目的本研究通过观察环氧合酶2(Cox-2)抑制剂塞来昔布与哺乳动物雷帕霉素靶蛋白(mTOR)抑制剂依维莫司对大鼠嗜铬细胞瘤细胞PC12的裸鼠移植瘤生长的影响,探讨依维莫司对大鼠嗜铬细胞瘤肿瘤生长和血管生成的抑制作用。方法用大鼠嗜铬细胞瘤细胞PC12接种于裸鼠皮下,建立移植瘤模型,15d后将荷瘤裸鼠随机分为4组,每组12只,分别为依维莫司组(依维莫司灌胃1mg/kg)、塞来昔布组(塞来昔布100mg/kg灌胃)、联合组(依维莫司1mg/kg+塞来昔布100mg/kg灌胃)、对照组(生理盐水灌胃10mL/kg),用药3周,第4周后测量裸鼠移植瘤的体积变化以及裸鼠的生存时间,采用免疫组化方法检测肿瘤组织中血管内皮生长因子(VEGF)的表达,采用Western blotting法检测肿瘤组织中VEGF的表达。结果第4周时移植瘤体积:对照组为(4 159.72±651.84)mm3,依维莫司组为(2 816.49±332.05)mm3,塞来昔布组为(4 018.38±527.46)mm3,联合组为(1 035.28±177.30)mm3,联合组与前3组均存在显著性差异(P<0.01)。平均生存时间:对照组(23.3±2.8)d,依维莫司组(36.8±3.6)d,塞来昔布组(26.4±2.4)d,联合组(45.9±4.5)d,用Kaplan-meier,Log-rank方法分析,联合组与前三组的生存函数的差异有统计学意义(P<0.05)。实验组肿瘤组织的VEGF表达明显低于对照组(P<0.05)。结论塞来昔布联合依维莫司对大鼠嗜铬细胞瘤裸鼠移植瘤有明显抑制作用,并可降低肿瘤组织中VEGF的表达。

Objective To investigate the combinational effect of mammalian target of rapamycin （mTOR） inhibitor everolimus and cyclooxygenase-2 （cox-2） inhibitor celecoxib in the implanted malignant pheochromocytoma nude mice and to explore the inhibitory mechanism of them on the tumor growth and angiopoiesis of malignant pheochromocytoma.Methods We created the malignant pheochromocytoma xenograft model by implanting PC12 cells in the left flank of nude mice.After 15 days,nude mice were randomly divided into four groups：the everolimus group （receiving everolimus by gavage at a dose of 1 mg/kg）,the celecoxib group （receiving celecoxib by gavage at a dose of 100 mg/kg）,the combination group （receiving everolimus by gavage at a dose of 1 mg/kg and celecoxib by gavage at a dose of 100 mg/kg） and the control group （treated with NS by gavage at a dose of 10 mL/kg）.After 3 weeks of treatment,we obtained the tumors,and measured the tumor volumes in the 4th week.During this time,we observed the change of tumor volumes and kept a record of the survival time.We detected the expressions of vascular endothelial growth factor （VEGF） by immunohistochemical staining and Western blotting.Results In the 4th week,the tumor size was （2 816.49±332.05）mm3 in the everolimus group,（4 018.38±527.46）mm3 in the celecoxib group,（4 159.72±651.84）mm3 in the control group,（1 035.28± 177.30）mm3 in the combination group.The growth of tumor in the combination group was slower than that in the other three groups,which had a statistical significance （P＜0.01）.The average survival time of the everolimus group,celecoxib group,control group,and the combination group was （36.8 ± 3.6） days,（26.4±2.4） days,（23.3±2.8） days,and （45.9±4.5） days,with statistical significance in these data （P＜0.05）.The expression of VEGF of tumor issues in the combination group was significantly lower than that in the control group （P＜ 0.05）.Conclusions Everolimus combined with celecoxib has a significant effect on the transplanted pheochromocytoma in nude mice and suppresses the expression of VEGF in the tumor tissues.