人肺腺癌细胞系中SIRT1表达与奈达铂敏感性的关系

Expression of SIRT1 in human lung adenocarcinoma cells and its relation to the susceptibility of NDP

目的探讨5株人肺腺癌细胞系HCC827、H1650、H1975、A549和H1299中沉默信息调节因子1(Sirtuin 1,SIRT1)与奈达铂(Nedaplatin,NDP)药物敏感性的关系。方法采用实时定量PCR及western blot检测5株人肺腺癌细胞系SIRT1 m RNA及蛋白质表达水平;NDP作用于细胞后,用CCK-8法检测细胞活力并计算半数生长抑制浓度值(the half growth inhibition concentration,IC50);通过si RNA干扰技术下调A549、H1299、H1650和H1975细胞系中SIRT1的表达,采用CCK-8法和流式细胞术分别检测NDP对细胞存活率和细胞凋亡的影响。结果与HCC827细胞(m RNA和蛋白质相对表达量分别为1.00和0.11±0.02)相比,H1650、H1975、A549和H1299细胞中SIRT1 m RNA(分别为4.53±0.74、3.11±0.64、15.76±2.28和18.09±1.17)和蛋白质表达水平(分别为0.23±0.03、0.21±0.02、0.52±0.11和0.56±0.08)均明显上调,差异有统计学意义(F分别为122.10和26.50,P<0.01);A549和H1299细胞对NDP的敏感性[IC50值分别为(7.38±1.59)μmol/L和(8.14±1.43)μmol/L]明显高于HCC827、H1650和H1975细胞[IC50值分别为(26.16±4.35)μmol/L、(22.29±3.26)μmol/L和(24.41±2.58)μmol/L],差异有统计学意义(F=30.86,P<0.01)。A549和H1299细胞转染并经NDP处理后,si SIRT1组细胞存活率明显高于NC组(F分别为235.10和39.20,P<0.01),细胞凋亡率明显低于NC组(t分别为7.29和6.68,P<0.05);而在H1650和H1975细胞中,si SIRT1组细胞存活率明显低于NC组(F分别为185.40和60.09,P<0.01),细胞凋亡率明显高于NC组(t分别为6.15和31.36,P<0.01)。结论在SIRT1高表达的A549和H1299细胞中SIRT1表达增加了细胞对NDP敏感性,而SIRT1中表达的H1650和H1975细胞中SIRT1表达降低了细胞对NDP的敏感性,提示在人肺腺癌细胞中SIRT1可能在铂类耐药发挥双重作用。

Objective To investigate the expression of Situin 1（ SIRT1） in 5 strains of human lung adenocarcinoma cell lines,including HCC827,H1650,H1975,A549 and H1299,and its relation to the susceptibility of nedaplatin（ NDP）. Methods The SIRT1 m RNA and protein levels in 5 strains of human lung adenocarcinoma cells were detected by real-time quantitative PCR and Western blot,respectively. The viability of cells treated with NDP was detected by the CCK-8 method and the half growth inhibition concentration（ IC50） was calculated. After the expressions of SIRT1 in A549,H1299,H1650 and H1975 cells were down-regulated by the si RNA interference,the effects of NDP on the viability and apoptosis of these cells were determined by the CCK-8 method and flow cytometry,respectively.Results The expression levels of SIRT1 m RNA（ 4.53 ± 0.74,3.11 ± 0.64,15.76 ± 2.28 and 18.09 ± 1.17） and protein（ 0.23 ± 0.03,0.21 ± 0.02,0.52 ± 0.11 and 0.56 ± 0.08） in H1650,H1975,A549 and H1299 cells were significantly higher than that in HCC827 cells（ 1.00 for SIRT1 m RNA and 0.11 ± 0.02 for SIRT1 protein,F = 122.10 and 26.50,respectively,P〈0.01）.The susceptibility of A549 and H1299 cells to NDP [IC50=（ 7.38 ± 1.59） and（ 8.14 ± 1.43） μmol/L,respectively]was significantly higher than that of HCC827,H1650 and H1975 cells [IC50=（ 26.16±4.35）,（ 22.29±3.26） and（ 24.41 ± 2.58）,respectively,F =30.86,P〈0.01].The survivals of A549 and H1299 cells transfected by si SIRT1 and treated with NDP were significantly higher than that in the NC group（ F = 235.10 and 39.20,respectively,P〈0.01）,and the apoptotic rates were the reverse（ t = 7.29 and 6.68,respectively,P〈0.05）. However,the survivals of H1650 and H1975 cells transfected by si SIRT1 and treated with NDP were significantly lower than that in the NC group（ F = 185.40 and 60.09,respectively,P〈0.01）,and the apoptotic rates were the reverse（ t = 6.15 and31.36,respectively,P〈0.01）.Conclusion The expression of SIRT1 in A549 and H1299 cells with high expression of SIRT1 increases their susceptibility to NDP,while that in H1650 and H1975 cells with moderate expression of SIRT1 decreases their susceptibility to NDP,indicating that SIRT1 may play dual roles in the resistance of human lung adenocarcinoma cells to platinum.