Akt抑制剂MK2206对乳腺癌细胞增殖和凋亡的影响

Effects of Akt inhibitor MK2206 on proliferation and apoptosis of breast cancer cells

目的:研究新型Akt抑制剂MK2206对体外培养的人乳腺癌T47D和MDA-MB-231细胞株增殖和凋亡的影响,并初步探讨其可能的作用机制。方法:以不同浓度的MK2206作用于人乳腺癌T47D和MDA-MB-231细胞,采用MTT法检测细胞的增殖抑制率,FCM法检测细胞的凋亡率,Western印迹法检测细胞中caspase-3、多聚ADP核糖聚合酶(polyADP-ribosepolymerase,PARP)、bcl-2、bax、磷酸化Akt(phosphorate-Akt,p-Akt)和总Akt(total-Akt,T-Akt)蛋白表达水平的变化。结果:0.1、1、10和100nmol/LMK2206作用细胞24h后,可明显抑制T47D和MDA-MB-231细胞的增殖和诱导细胞凋亡,其作用随着药物浓度的增加而增强。MK2206可促进乳腺癌细胞中caspase-3和PARP蛋白剪切,上调bax蛋白表达,下调bcl-2和p-Akt蛋白的表达,且均呈剂量依赖性,但对T-Akt表达却无明显影响。结论:MK2206可抑制乳腺癌T47D和MDA-MB-231细胞的增殖并诱导其凋亡,其机制可能与抑制Akt磷酸化从而阻断PI3K/Akt信号转导途径有关。

Objective：To study the effects of Akt inhibitor MK2206 on the proliferation and apoptosis of human breast cancer cell lines T47D and MDA-MB-231,and to elucidate the possible mechanism of such effects.Methods：Human breast cancer T47D and MDA-MB-231 cells were treated with different concentrations of MK2206,respectively.The inhibitory effect of MK2206 on cell proliferation was examined by MTT assay.The apoptosis rates of T47D and MDA-MB-231 cells induced by MK2206 were detected by flow cytometry（FCM）.The expression levels of caspase-3,poly（ADP-ribose） polymerase（PARP）,bcl-2,bax,phosphorate-AKT（p-AKT） and total Akt（T-Akt） proteins were detected by Western blotting.Results：The proliferation of T47D and MDA-MB-231 cells were inhibited after treatment with MK2206 at 0.1,1,10 and 100 nmol/L for 24 h,respectively.The apoptosis rates of T47D and MDA-MB-231 cells were increased induced by MK2206.The expression levels of caspase-3,PARP and bax proteins were up-regulated,while the expression levels of bcl-2 and p-Akt proteins were down-regulated.All of these effects occurred in a dose-dependent manner.MK2206 had no significant effect on the expression of T-Akt.Conclusion：MK2206 can inhibit the proliferation and induce the apoptosis in human breast cancer cell lines T47D and MDA-MB-231.These effects may be related with the down-regulation of p-AKT and the inhibition of PI3K-Akt signaling pathway.