微小RNA-21在顺铂联合5-氟尿嘧啶抑制肺癌细胞株作用中的表达变化

目的探讨顺铂和5-氟尿嘧啶在体外联合用药对肺癌细胞株A549细胞存活率、细胞周期的影响以及在这过程中微小RNA-21(microRNA-21,miR-21)表达水平的变化。方法顺铂和5-氟尿嘧啶单药或联合用药处理肺癌A549细胞后,采用CCK-8法检测细胞存活率;倒置显微镜观察细胞形态变化;流式细胞仪技术检测细胞周期;实时荧光定量PCR检测miR-21的表达变化。结果顺铂和5-氟尿嘧啶单药对A549细胞的抑制作用都具有浓度依赖性,两者联合用药48h后细胞的存活率明显低于单药组(P0.05),并且细胞形态改变更加明显,悬浮、变圆的细胞也更多;顺铂处理A549细胞后,将细胞阻滞于S期和G2期,5-氟尿嘧啶阻滞A549细胞于S期,联合用药后细胞阻滞于S期和G2期;随着顺铂和5-氟尿嘧啶作用浓度的增加,miR-21的表达水平上调,联合用药后miR-21的表达亦上调,但趋势没有顺铂组明显(P0.05)。结论顺铂在体外联合5-氟尿嘧啶对A549细胞存活率的抑制有协同作用,同时可以上调细胞内miR-21表达水平。

Differential expression of miR-21 in the suppression of A549 cells with cisplatin and 5-fluorouracil

Objective To investigate the effect of cisplatin in combination with 5-fluorouracil in vitro on the viabili- ty, cell cycle and miR-21 expression level of A549 cells. Methods The inhibitory effect of cisplatin, 5-fluorouracil, cis- platin in combination with 5-fluorouracil on the viability of A549 cells were tested by CCK-8 assay in vitro. The change of cell morphology was observed with inverted microscope, while cell cycle was assayed by flow cytometry. The expression of miR-21 was measured by real-time quantitative PCR. Results The growth of A549 cells was inhibited by cisplatin in a dose-dependent manner, as well as 5-fluorouracil. The suppression ratio of the combined group treated with cisplatin com- bined with 5-fluorouracil was higher than that of the single drug group（ P〈0. 05） ; The change of cell morphology of combi- nation group was more apparent than that of the monotherapy group, and more suspension and round cells were observed. Cisplatin arrested A549 cell cycle at S and G2 phase. In 5-fluorouracil group, cells were arrested at S phase. In combination group, Gl phase cells decreased while S/G2 phase cells increased. With the increase of the concentration of cisplatin and 5- flaorouracil, the expression level of miR-21 was increased. The expression level of miR-21 in the combination group was al- so increased, but the trend was not obvious as that in monotherapy group（ P〈0. 05）. Conclusions The viability of A549 cells could be inhibited and the expression level of miR-21 might be increased by cisplatin in combination with 5-fluoroura- ell in vitro.