姜黄素联合KLF8基因siRNA调控JAK2/STAT3信号通路对乳腺癌细胞生长抑制作用的研究

摘要

Objective To investigate the effect of curcumin combined with KLF8 gene siRNA on the growth inhibition of breast cancer cells by regulating of JAK2/STAT3 signaling pathway. Methods Human breast cancer MCF-7 cells were randomly divided into negative control group, KLF8-siRNA group, curcumin group and KLF8-siRNA+curcumin group, AG490 as a AK2/STAT3 signaling pathway inhibitor;CCK-8 kit and flow cytometry were used to detect the cell viability and apoptosis rate after cells were treated for 48 h;JAK2/STAT3 signal pathway of pJAK2 and p-STAT3 and its target gene Cyclin D1and Bcl-2 protein expression were detected by Western blot.Results The expression of KLF8 in MCF-7 cells transfected with KLF8-siRNA was significantly decreased.The cell viability and protein expression of Cyclin D1, Bcl-2, p-JAK2 and p-STAT3 in KLF8-siRNA group and curcumin group were significantly lower than negative.In the control group, higher than KLF8-siRNA+curcumin group, the apoptosis rate was significantly higher than that of the negative control group, lower than KLF8-siRNA+curcumin group (P＜0.05), cells co-treated curcumin, KLF8-siRNA and JAK2/STAT3 signal inhibitor AG490 displayed that cell viability was significantly lower than that of curcumin and KLF8-siRNA, and the apoptosis rate was increased.The expression of Cyclin D1, Bcl-2, p-JAK2 and p-STAT3 was decreased (P＜0.05). Conclusion Down regulation of KLF8 gene expression and curcumin can reduce the activity and induce apoptosis of breast cancer cells by inhibiting of JAK2/STAT3 signaling pathway.The combination of them has stronger effect on cell viability and apoptosis.%目的 探讨姜黄素联合Krüppel样转录因子8(KLF8)基因小干扰RNA(siRNA)调控蛋白酪氨酸激酶2/信号转导与转录因子3(JAK2/STAT3)信号通路对乳腺癌细胞生长抑制的影响.方法 将生长至对数期的人乳腺癌MCF-7细胞随机分为阴性对照组、KLF8-siRNA、姜黄素组和KLF8-siRNA+姜黄素组;CCK-8试剂及流式细胞仪分别检测处理48 h各组细胞的活力及凋亡率;Western blot检测JAK2/STAT3信号通路磷酸化的蛋白酪氨酸激酶2(p-JAK2)和磷酸化的信号转导与转录因子3(p-STAT3)及靶基因细胞周期素D1(Cyclin D1)和B细胞淋巴瘤/白血病-2(Bcl-2)的蛋白表达.结果 转染KLF8-siRNA的MCF-7细胞KLF8的表达明显降低;KLF8-siRNA组和姜黄素组的细胞活力及Cyclin D1、Bcl-2、p-JAK2和p-STAT3的蛋白表达均显著低于阴性对照组,高于KLF8-siRNA+姜黄素组,细胞凋亡率显著高于阴性对照组,低于KLF8-siRNA+姜黄素组(P＜0.05);姜黄素、KLF8-siRNA及JAK2/STAT3信号抑制剂AG490共同处理细胞相对于姜黄素和KLF8-siRNA处理的细胞活力明显降低,凋亡率升高,Cyclin D1、Bcl-2、p-JAK2和p-STAT3的表达降低(P＜0.05).结论 下调KLF8基因表达和姜黄素均能通过抑制JAK2/STAT3信号通路降低乳腺癌细胞活力,诱导细胞凋亡,两者联合对细胞活力及凋亡的影响作用更强.