摘要
目的:探讨雷帕霉素(rapamycin,RAPA)对不同肿瘤细胞Bax/Bcl-2和活性caspase-3表达的影响及其可能的机制。方法:采用RAPA处理肺腺癌A549细胞、人成神经细胞瘤SH-SY5Y细胞和人骨肉瘤MG63细胞后,MTT法检测细胞的相对增殖率,蛋白质印迹法检测细胞中Bcl-2、Bax和活性caspase-3的表达以及细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)和Akt活性的变化;RAPA联合ERK抑制剂U0126或PD98059以及联合Akt抑制剂wortmannin处理MG63和SH-SY5Y细胞后,分别用MTT法和蛋白质印迹法检测细胞的相对增殖率和Bcl-2、Bax、活性caspase-3的表达。结果:在A549细胞中,RAPA上调细胞Bax/Bcl-2和活性caspase-3的表达(P<0.05),细胞的相对增殖率下降(P<0.05)。在MG63细胞中,RAPA通过ERK上调Bcl-2和Bax的表达,Bax/Bcl-2和活性caspase-3的表达以及细胞的相对增殖率无明显变化;ERK抑制剂U0126或PD98059逆转RAPA导致的Bcl-2上调,联合RAPA作用后细胞中Bax/Bcl-2和活性caspase-3的表达上调(P<0.05),细胞的相对增殖率降低(P<0.05)。在SH-SY5Y细胞中,RAPA通过Akt上调Bcl-2的表达,Bax/Bcl-2降低(P<0.05),细胞的相对增殖率上升(P<0.05);Akt抑制剂wortmannin逆转RAPA导致的Bcl-2上调,联合RAPA作用后细胞中Bax/Bcl-2和活性caspase-3的表达上调(P<0.05),细胞的相对增殖率降低(P<0.05)。结论:RAPA在不同肿瘤细胞中可能通过调节不同的激酶影响Bax/Bcl-2和活性caspase-3的表达。
Objective： To investigate the effects of RAPA （rapamycin） on expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 in different types of tumor cells, and to explore the possible mechanism. Methods： Human lung adenocarcinoma A549 cells, human neuroblastoma SH-SY5Y cells and human osteosarcoma MG63 cells were treated with RAPA. The relative proliferative rates of cells were determined by MTT assay. The expression levels of Bcl-2, Bax and activated caspase-3 and the changes in activity of ERK （extracellular signal-regulated kinase） and Akt （protein kinase B） were examined by Western blotting. The relative proliferative rates and the expression levels of Bcl-2, Bax and activated caspase-3 in MG63 and SH-SY5Y cells after treatment with RAPA in combination with ERK inhibitor U0126 or PD98059 or RAPA in combination with Akt inhibitor wortmannin were examined by MTT and Western blotting, respectively. Results： The expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 were up-regulated （P 〈 0.05） and the relative proliferative rate was decreased in A549 cells after treatment with RAPA （P 〈 0.05）. The expression levels of Bax and Bcl-2 were up-regulated in MG63 cells after treatment with RAPA through the regulation of ERK, however, the expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 as well as the relative proliferative rate had no changes. ERK inhibitors U0126 or PD98059 reversed the RAPA-induced up-regulation of Bcl-2 expression in MG63 cells. The expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 were increased（P 〈 0.05） in MG63 cells after treatment with ERK inhibitor in combination with RAPA, while the relative proliferative rate was decreased （P 〈 0.05）. The expression level of Bcl-2 was up-regulated in SH- SY5Y cells after treatment with RAPA through the regulation of Akt, while the expression ratio of Bax/ Bcl-2 was down-regulated （P 〈 0.05）, and the relative proliferative rate was increased （P 〈 0.05）. Akt inhibitor wortmannin reversed the RAPA-induced up-regulation of Bcl-2 expression in SH-SY5Y cells. The expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 were increased （P 〈 0.05） in SH-SY5Y cells after treatment with RAPA in combination with Akt inhibitor, and the relative proliferative rate was decreased （P 〈 0.05）. Conclusion： The effects of RAPA on the expression ratio of Bax/Bcl-2 and the expression of activated caspase-3 in different types of tumor cells may be through regulation of different kinases.
出处
《肿瘤》
CAS
CSCD
北大核心
2013年第2期138-143,163,共7页
Tumor
