miR-192、miR-215及ERCC3在NSCLC细胞系A549放疗后的表达变化及意义

Changes in Expression of miR-192,miR-215 and ERCC3 after Radiotherapy and Their Significance in NSCLC A549 Cells

目的探讨非小细胞肺癌细胞系A549放疗后,miR-192、miR-215及ERCC3的表达变化及意义。方法体外常规培养的A549细胞分为对照组、20 Gy剂量放疗组及40 Gy剂量放疗组,采用RT-qPCR检测miR-192和miR-215变化,Western blot检测ERCC3蛋白表达情况。结果 A549细胞受不同剂量(20 Gy和40 Gy)的射线照射后,miR-192、miR-215表达上调。在20 Gy剂量组中,miR-192上调(4.27±0.56)倍,miR-215上调(6.58±0.56)倍。在40 Gy剂量组中,miR-192上调(4.94±0.39)倍,miR-215上调(7.48±0.47)倍。而ERCC3蛋白水平下调,相较于对照组(1.35±0.23),40 Gy剂量组中ERCC3表达量(0.28±0.08)呈5倍下降,与20 Gy组(0.63±0.14)相比,其值约呈2倍下降。结论在非小细胞肺癌中,放疗可上调miR-192和miR-215的表达,下调其下游靶基因ERCC3的表达,从而对放疗后DNA损伤及修复发挥调控作用。

Objective To investigate the changes in the expression of miR-192, miR-215 and ERCC3 after radiotherapy and their significance in non-small cell lung cancer （NSCLC）A549 cells. Methods Cultured A549 cells were divided into three groups： control group,20 Gy treatment group and 40 Gy treatment group. The expression of miR-192 and miR-215 was measured by RT-qPCR and ERCC3 protein expression was measured by western blot. Results The expression of miR-192 was up-regulated（4.27±0.56）fold and（4.94±0.39）fold by 20 and 40 Gy of ionizing radiation（IR）, respectively. The expression of miR-215 was up-regulated （6.58 ±0.56） fold and （7.48±0.47） fold by 20 and 40 Gy of IR, respectively. Compared with control group, the levels of ERCC3 protein expression were respectively down-regulated 2-fold and 5-fold by 20 and 40 Gy of IR （0.63±0.14 and 0.28±0.08 vs 1.35±0.23, respectively）. Conclusion The radiotherapy may decrease the expression of ERCC3 and increase the expression of miR-192 and miR-215 to regulate the process of DNA damage and repair in NSCLC.