【摘要】 目的研究As2O3单用及联用STI571对K562细胞bcr-abl蛋白酪氨酸磷酸化的影响,探讨其抗白血病的分子机制,为As2O3和STI571联合应用治疗CML提供理论依据。方法采用细胞增生实验检测细胞生长;采用Annexin蛳V/PI双染实验、DNA的PI染色及DNA电泳等方法检测细胞凋亡;运用免疫沉淀和Westernblot检测K562细胞bcr蛳abl蛋白酪氨酸磷酸化水平。结果As2O3和STI571明显抑制K562细胞生长,并检测出凋亡细胞群,DNA电泳出现“梯”状条带;bcr蛳Abl蛋白酪氨酸磷酸化水平出现时间剂量依赖性下调。结论As2O3和STI571能诱导K562细胞凋亡和抑制其增生,两药联用具有协同作用,机制似与下调K562细胞bcr-abl蛋白酪氨酸磷酸化有关。更多还原

【Abstract】 Objective To investigate the effects of As2O3 alone and in combination with STI571 on bcr- abl protein tyrosine phosphorylation in K562 cells and their molecular mechanism of antileukemia, to provide theoretical basis for clinical therapy of CML cases. Methods Cell growth was analyzed by the cell proliferation experiment. Apoptosis was analyzed by Annexin- V/PI staining, DNA- PI staining and DNA gel electrophoresis. bcr- abl protein tyrosine phosphorylation was studied by means of immunoprecipition and Western blot. Results After exposure to As2O3 and/or STI571, the growth of K562 cells was inhibited. The population of apoptotic cells could be assayed by flow cytometer. Typical DNA ladder was shown by DNA gel electrophoresis. Tyrosine phosphorylation level of bcr- abl was decreased in a time- and dose- dependent manner. Conclusions As2O3 and STI571 might induce apoptosis of the K562 cells and inhibit its proliferation by downregulating tyrosine phosphorylation of bcr- abl protein. The two drugs have synergistic effect.更多还原