siRNA沉默BRM增强胰腺癌细胞对吉西他滨敏感性的作用机制研究

Study on the Mechanism of siRNA Silencing BRM Enhancing the Sensitivity of Pancreatic Cancer Cells to Gemcitabine

目的:探讨siRNA沉默BRM增强胰腺癌细胞对吉西他滨敏感性的作用。方法:体外培养人胰腺癌Panc-1细胞,将阴性对照NC和BRM siRNA转染到Panc-1细胞,用RT-PCR和Western Blot法检测Panc-1细胞BRM的表达,以鉴定BRM特异性siRNA沉默效果。用不同浓度的吉西他滨进行干预,检测细胞增殖率,计算半数抑制浓度(IC50),同时检测Panc-1细胞凋亡率和Panc-1细胞中JAK2、STAT3、p-STAT3和Survivin蛋白表达水平。结果: BRM siRNA组Panc-1细胞中BRM mRNA和蛋白表达较空白对照组和NC对照组显著降低(P<0.05);BRM siRNA组吉西他滨对Panc-1细胞增殖的抑制较空白对照组和NC对照组增强(P<0.05),通过计算,空白对照组、NC对照组和BRM siRNA组的IC50分别为5.18ug/mL、5.05ug/mL和3.05ug/mL;给予终浓度为3.0ug/mL的吉西他滨干预,BRM siRNA组Panc-1细胞凋亡率较空白对照组和NC对照组显著增高(P<0.05),STAT3变化不显著(P>0.05),JAK2、p-STAT3和Survivin蛋白表达显著降低(P<0.05)。结论:通过siRNA沉默BRM的表达后可以增加Panc-1细胞对西他滨的敏感性,可能与BRM激活JAK2/STAT3通路促进胰腺癌生长和耐药有关。

Objective: To investigate enhancement of silencing BRM gene by siRNA on the sensitivity of human pancreatic cancer cell line to gemcitabine. Methods: Panc-1 cells from human pancreatic cancer in vitro were cultured. Negative control NC and BRM siRNA were transfected into Panc-1 cells cultured in vitro. The expression of BRM in Panc-1 cells was detected by RT-PCR and Western Blot,so as to identify the silencing effect of BRM-specific siRNA. Different concentrations of gemcitabine were used to detect the cell proliferation rate,and the half-inhibitory concentration (IC50) was calculated. The apoptosis rate of Panc-1 cells and the protein expression levels of JAK2,STAT3,p-STAT3 and Survivin in Panc-1 cells were detected. Results: The expression of BRM mRNA and protein in Panc-1 cells of BRM siRNA group was significantly lower than that of blank control group and NC control group (P<0.05). The inhibition rate of gemcitabine on Panc-1 cell proliferation in BRM siRNA group was higher than that in blank control group and NC control group (P<0.05);The IC50 of the blank control group,the NC control group and the BRM siRNA group were 5.18 ug/mL,5.05 ug/mL and 3.05 ug/mL,respectively;After gemcitabine treatment with the final concentration of 3.0ug/mL,the apoptotic rate of Panc-1 cells in BRM siRNA group was significantly higher than that in blank control group and NC control group (P<0.05),STAT3 was not significantly changed (P>0.05),while the expression of JAK2,p-STAT3 and Survivin protein was significantly decreased (P<0.05). Conclusion: Silencing BRM expression by siRNA can increase the sensitivity of Panc-1 cells to citrate,which may be related to the activation of JAK2/STAT3 pathway by BRM to promote pancreatic cancer growth and drug resistance.