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

摘要:

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；Western blot 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、50 μmol/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。

Abstract:

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：MTT 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 μmol/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-7B，mechanism of which may be related with the inhibition of STAT3 activity.