STAT3特异性抑制剂STA-21对乳腺癌MCF-7B细胞增殖及凋亡的影响

Effects of specific inhibitor of STAT3:STA-21 on the proliferation and apoptosis of breast cancer MCF-7B cells

目的:探讨信号传导与转录活化因子3(signal transducers and activators of transcription 3,STAT3)特异性抑制剂STA-21对乳腺癌MCF-7B细胞增殖及凋亡的影响。方法:空白组为单独培养MCF-7B细胞,实验组采用不同浓度STA-21作用于乳腺癌MCF-7B细胞后,用MTT法观察STA-21对MCF-7B细胞生长抑制的作用;流式细胞仪检测细胞周期及凋亡;Westernblot检测MCF-7B细胞P-STAT3、STAT3、细胞周期蛋白D1(CyclinD1)、Bcl-xl蛋白的表达。结果:MCF-7B细胞经各浓度STA-21(10、30、50μmol/L)作用后,其细胞增殖的抑制率及细胞凋亡率较空白组明显增加(P=0.000);流式细胞仪检测发现STA-21可导致MCF-7B细胞阻滞于G1期;Western blot结果显示与空白组相比,STA-21可降低MCF-7B细胞P-STAT3、CyclinD1、Bcl-xl蛋白的表达(P=0.000),但对STAT3蛋白的表达基本无影响(P=0.367)。结论:STA-21可在一定程度上抑制MCF-7B细胞的增殖及促进凋亡,其作用机制可能与抑制STAT3活性有关。

Objective：To investigate the effects of STA-21,a specific inhibitor of signal transducers and activators of transcription 3 （STAT3） on the proliferation and apoptosis of breast cancer MCF-7B cells. Methods ：MTY assay was applied to observe the inhibi- tion of STA-21 on growth of MCF-7B cells after MCF-7B cells being treated with different concentrations of STA-21. Apoptosis and cell cycle of MCF-7B cells were examined by flow cytometry（FCM）. Expressions of P-STAT3, STAT3, CyclinD1 and Bcl-xl protein in MCF-7B cells were detected by Western blot. Results：After cells being exposed to different concentrations （ 10,30,50 ~mol/L）of STA-21, inhibitory rate and apoptotic rate were increased markedly（P=0.000）. It was showed by FCM assay that STA-21 could inhibit the MCF-7B cells at G1 phase. Meanwhile,STA-21 could reduce the expressions of P-STAT3, CyclinD1 and Bcl-xl protein（P=0.000）, but STA-21 exerted no effect on STAT3 protein（P=0.367）. Conclusions：Our study demonstrates that STA-21 can inhibit prolifer- ation and promote apoptosis of MCF-TB, mechanism of which may be related with the inhibition of STAT3 activity.