环状RNA circ-FOXM1降低克唑替尼对肺癌细胞抑制效果的作用机制研究

A study on the mechanism of circular RNA circ-FOXM1 reducing the inhibitory effect of crizotinib on lung cancer cells

目的探讨环状RNA circ-FOXM1降低克唑替尼对肺癌细胞抑制效果的作用机制。方法构建克唑替尼耐药肺癌细胞株H2228/CR。采用实时荧光定量聚合酶链式反应(qRT-PCR)法检测circ-FOXM1在BEAS-2B、H2228、H2228/CR细胞中的表达。将H2228细胞分为circ-FOXM1过表达组和过表达对照组。将H2228/CR细胞分为circ-FOXM1沉默组和沉默对照组。采用四甲基偶氮唑蓝(MTT)法检测细胞的半抑制浓度(IC_(50))。经克唑替尼干预处理后,采用流式细胞术检测各组细胞的凋亡率,采用Transwell实验检测各组细胞迁移数,采用Western blot实验检测各组细胞磷酸化的磷脂酰肌醇3激酶(p-PI3K)、磷脂酰肌醇3激酶(PI3K)、磷酸化的蛋白激酶B(p-AKT)、蛋白激酶B(AKT)的表达水平。结果H2228/CR细胞circ-FOXM1表达水平高于H2228细胞,H2228细胞circ-FOXM1表达水平高于BEAS-2B细胞,差异有统计学意义(P<0.05)。克唑替尼对过表达组细胞的IC_(50)显著高于过表达对照组细胞(P<0.05)。克唑替尼对沉默组细胞的IC_(50)显著低于沉默对照组细胞(P<0.05)。经克唑替尼干预处理后,过表达组的细胞凋亡率低于过表达对照组,细胞迁移数、p-PI3K/PI3K比值、p-AKT/AKT比值均高于过表达对照组,差异有统计学意义(P<0.05)。沉默组的细胞凋亡率高于沉默对照组,细胞迁移数、p-PI3K/PI3K比值、p-AKT/AKT比值均低于沉默对照组,差异有统计学意义(P<0.05)。结论circ-FOXM1可能通过激活PI3K/AKT信号通路降低克唑替尼对肺癌细胞的抑制效果。

Objective To explore the mechanism of circular ribonucleic acid(cricRNA)circ-FOXM1 reducing the inhibitory effect of crizotinib on lung cancer cells.Methods A crizotinib-resistant lung cancer cell line H2228/CR was constructed.Quantitative real-time polymerase chain reaction(qRT-PCR)was used to detect the expressions of circ-FOXM1 in BEAS-2B,H2228 and H2228/CR cells.H2228 cells were divided into circ-FOXM1 overexpression group and overexpression control group.H2228/CR cells were divided into circ-FOXM1 silencing group and silencing control group.The half maximal inhibitory concentration(IC_(50))of the cells was detected by using methyl thiazolyl tetrazolium(MTT)assay method.After the intervention of crizotinib,the apoptosis rate of the cells in each group was detected by flow cytometry,and the number of cell migration in each group was detected by Transwell assay.The expression levels of phosphorylated phosphatidylinositol 3 kinase(p-PI3K),phosphatidylinositol 3 kinase(PI3K),phosphorylated protein kinase B(p-AKT)and protein kinase B(AKT)in the cells of each group were detected by using Western blot assay.Results The expression level of circ-FOXM1 in the H2228/CR cells was higher than that in the H2228 cells,and the expression level of circ-FOXM1 in the H2228 cells was higher than that in the BEAS-2B cells,and the differences were statistically significant(P<0.05).The IC_(50) of crizotinib in the cells of the overexpression group was significantly higher than that in the cells of the overexpression control group(P<0.05).The IC_(50) of crizotinib in the cells of the silencing group was significantly lower than that in the cells of the silencing control group(P<0.05).After the intervention of crizotinib,the apoptosis rate in the overexpression group was lower than that in the overexpression control group,and the number of cell migration,p-PI3K/PI3K ratio and p-AKT/AKT ratio in the overexpression group were higher than those in the overexpression control group,and the differences were statistically significant(P<0.05).The apoptosis rate in the silencing group was higher than that in the silencing control group,and the number of cell migration,p-PI3K/PI3K ratio and p-AKT/AKT ratio in the silencing group were lower than those in the silencing control group,and the differences were statistically significant(P<0.05).Conclusion Circ-FOXM1 may reduce the inhibitory effect of crizotinib on lung cancer cells by activating PI3K/AKT signaling pathway.