摘要
目的:观察他克莫司(FK506)对5氟尿嘧啶(5FU)诱导肝癌SMMC7721细胞凋亡的影响,并对其机制进行初步探讨。方法:体外培养人肝癌细胞株SMMC-7721;应用流式细胞仪检测5FU及联合FK506对细胞凋亡和细胞周期的影响;TransAMNF-κB核转录因子活性检测试剂盒检测NFκBp65活性;细胞免疫组织化学检测NFκBp65激活后入核情况;免疫印迹分析CyclinD1蛋白表达差异。结果:5-FU可诱导肝癌细胞凋亡,其作用随浓度的增加而增强(P<0.05);随着5-FU用药浓度的增加,S期细胞比例和细胞增殖指数(PI)也增加;5-FU可激活NFκB而入核,CyclinD1蛋白的表达逐渐增强。FK506预处理增强了5-FU诱导SMMC7721细胞凋亡的作用,同时S期细胞比例和PI也减少;FK506预处理可抑制NF-κB入核,并可下调CyclinD1基因的表达。结论:FK506能够协同5FU诱导肝癌细胞株凋亡,增强肝癌细胞株对5-FU的敏感性,这种作用可能是通过抑制NFκB活性进而下调CyclinD1基因的表达,导致G0/G1期停滞而实现。
Objective:To investigate the influence of tacrolimus on fluorouracil-induced apoptosis of hepatocellular carcinoma. Methods: SMMC-7721 cells used in the experiment were cultured in vitro. Flow cytometry (FCM) was used to examine the effects of 5-FU (with or without FK506) on the apoptosis and cell cycle of SMMC-7721 cells. Cyclin D 1 protein was estimated by Western blot, and nuclear factor-κB(NF-κB) activity of SMMC-7721 cells was measured by immunohistochemistry and an ELISA-based method. Results: 5-FU induced apoptosis in a concentration-dependent manner at all experimental concentrations in SMMC-7721 cells(P<0.05). The percentage of G 0/G 1-phase cells and proliferation index (PI) increased with the concentration of 5-FU. 5-FU increased Cyclin D 1 protein levels and the activity of NF-κB. Pretreatment with FK506 for 2 hours markedly enhanced the effect of 5-FU in inducing apoptosis. Furthermore, FK506 also inhibited NF-κB activity and decreased protein and mRNA levels of Cyclin D 1. Conclusion: These results demonstrate that FK506 can enhance 5-FU's effect in inducing apoptosis of SMMC-7721 cells. The synergic effect might be associated with G 0/G 1-phase stasis caused by inhibiting nuclear factor-κB activity through downregulating over-expression of Cyclin D 1.
出处
《第二军医大学学报》
CAS
CSCD
北大核心
2005年第6期663-666,共4页
Academic Journal of Second Military Medical University
