摘要
目的 本文研究ST2 32 5对HER2 /neu受体的下游信号转导途径的抑制作用及其对乳腺癌BT4 74细胞周期的影响。方法 免疫印迹法检测蛋白表达量和磷酸化蛋白量的变化 ;流式细胞术检测细胞周期的分布。结果 ST2 32 5抑制BT4 74细胞HER 2 /neu受体的自身磷酸化 ,IC50 为 8 7μmol·L-1,对HER2 /neu的表达没有任何影响。ST2 32 5抑制BT4 74细胞磷酸化的MAPK和AKT。ST2 32 5处理BT4 74细胞 2 4h后 ,流式细胞仪分析可见细胞周期停止于G1期 ;Westernblot法检测呈现在在ST2 32 5处理后 ,细胞中p2 7上调 ,Rb的高磷酸化状态下降 ,CyclinD1蛋白水平下降。 结论 ST2 32 5能抑制乳癌BT4 74细胞HER2 /neu受体酪氨酸激酶信号转导途径 ,诱导乳腺癌细胞BT4 74停止于G1期 ,且与 p2 7上调、Rb的高磷酸化状态下降、CyclinD1蛋白水平下降有关。
Aim The aim of this study is to determine effect of ST2325 on HER2/neu tyrosine kinase signal pathway and cell cycle in breast cancer BT474 cells. Methods Protein expression was detected with immunoblot analysis. Cell cycle distribution was examined using flow cytometry.Results ST2325 inhibited tyrosine phosphorylation of HER-2/neu in a dose-dependent manner with half maximal inhibition occurring at a concentration of 8.7 μmol·L -1 without reduced HER-2/neu receptor protein expression. Activation of MAPK and AKT, downstream molecules of HER-2/neu-mediated signal transduction pathway was inhibited following exposure to ST2325. After BT474 cells were treated with different concentrations of ST2325 for 24 h, the results of flow cytometry analysis showed cell cycle arrest in G 1 phase. Western blot assay showed up-regulation of p27 protein expression and decrease of hyperphosphorylated Rb and cyclin D1 protein expression.Conclusions ST2325 inhibits HER2 tyrosine kinase phosphorylation and induces G 1 arrest in BT474 cells. Cell cycle arrest in G 1 is associated with p27 up-regulation, decrease of cyclin D1 protein and hyperphosphorylated Rb.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2004年第12期1361-1365,共5页
Chinese Pharmacological Bulletin
基金
国家自然科学基金资助项目
No 3 0 1710 92
广东省自然科学基金资助项目
No 0 13 12 6
