长链非编码RNA BANCR与非小细胞肺癌EGFR-TKI耐药的相关性研究

Correlation of long chain non-coding RNA BANCR and EGFR-TKI drug resistance of nonsmall cell lung cancer

目的:探讨长链非编码RNA BANCR与非小细胞肺癌表皮生长因子受体-酪氨酸激酶抑制剂(epidermal growth factor receptor-tyrosine kinase inhibitor,EGFR-TKI)耐药之间的相关性。方法:选择EGFR 19外显子缺失突变的细胞株PC9以及EGFR-TKI吉非替尼诱导的耐药细胞株PC9/GR进行研究。应用实时荧光定量PCR法(qRT-PCR)检测PC9/GR及PC9细胞中BANCR的表达差异。在PC9/GR细胞中过表达BANCR,应用CCK-8法检测细胞对吉非替尼药物敏感性,克隆形成试验检测细胞增殖能力,流式细胞术检测细胞凋亡情况,Western blot检测上皮间质转化相关蛋白的表达。结果:①BANCR在PC9/GR细胞中显著低表达(P<0.05)。②在PC9/GR细胞中过表达BANCR后,相对于对照组,吉非替尼对PC9/GR细胞的半数抑制浓度(half inhibition concentration,IC50)降低(P<0.05)。过表达BANCR后PC9/GR细胞增殖能力减弱,经吉非替尼处理后细胞凋亡增多(P<0.05)。③Western blot结果显示过表达BANCR的PC9/GR细胞E-钙黏蛋白(E-cadherin)表达水平明显升高,N-钙黏蛋白(N-cadherin)表达水平明显降低(P<0.05)。结论:长链非编码RNA BANCR可诱导细胞凋亡,抑制细胞增殖;过表达BANCR可以增加PC9/GR细胞对吉非替尼的敏感性,逆转其耐药性,其机制可能与调控上皮间质转化有关。

Objective:To explore correlation between long chain non-coding RNA(lncRNA)BANCR and epidermal growth factor receptor-tyrosine kinase inhibitor(EGFR-TKI)drug resistance of non-small cell lung cancer.Methods:Mutated cell strain PC9 with EGFR exon 19 deletion and drug resistant cell strain PC9/GR induced by EGFR-TKI gefitinib were selected for research.Real time fluorescent quantitative PCR(qRT-PCR)was applied to examine expression difference of BANCR in PC9/GR and PC9.BANCR was over expressed in PC9/GR cells and then CCK-8 method was used to examine drug susceptibility of the cells to gefitinib and clone formation assay to examine cell reproductive capacity.Meanwhile,flow cytometry was adopted to examine cell apoptosis and Western blot to check expression of epithelial-mesenchymal transition related proteins.Results:①BANCR was significantly low expressed in PC9/GR cells(P<0.05).②When BANCR was over-expressed in PC9/GR cells,compared with control group,half inhibition concentration(IC50)of gefitinib was reduced(P<0.05),cell reproductive capacity was lowered,and cell apoptosis increased after being handled with gefitinib(P<0.05).③Compared with control group,Western blot showed that expression level of E-cadherin in the PC9/GR cells over-expressed BANCR was significantly elevated and expression level of N-cadherin was remarkably lowered(P<0.05).Conclusion:Long chain non-coding RNA BANCR can induce cell apoptosis and inhibit cell reproduction.Over expressed BANCR can increase sensitivity of PC9/GR cells to gefitinib and thus reverse drug resistance.This mechanism might work through regulating EMT process.