荷包牡丹碱对人肺癌A549细胞生长及端粒酶活性的抑制作用

目的探讨荷包牡丹碱对人肺癌A549细胞生长的抑制作用及其作用机制。方法 A549细胞加入荷包牡丹碱0～200μmol.L-1分别作用24,48和72 h,MTT法测定A549细胞的生长抑制作用。荷包牡丹碱0～20μmol.L-1作用72 h,端粒重复序列扩增(TRAP)法测定端粒酶活性。变温紫外法检测荷包牡丹碱9μmol.L-1对端粒酶G-四链体的稳定作用。结果荷包牡丹碱25,50,100和200μmol.L-1作用细胞72 h后的抑制率分别为33.4%,88.2%,88.6%和89.4%,明显高于正常对照组细胞(P<0.05),并具有量效(r=0.906,P<0.05)和时效(r=0.949,P<0.05)性。与正常对照组相比,荷包牡丹碱5,10,15和25μmol.L-1可有效抑制A549细胞端粒酶的活性(P<0.05),相对TRAP端粒酶活性从正常对照组的1.471±0.102分别降低为1.093±0.054,1.013±0.016,0.554±0.034,0.365±0.081(P<0.05)。荷包牡丹碱9μmol.L-1使G-四链体的熔点值从正常对照组的48℃提高到54℃。结论荷包牡丹碱可以通过稳定G-四链体结构,抑制端粒酶活性,有效抑制人肺腺癌细胞A549的生长。

Inhibitory effect of dicentrine on human lung cancer cell line A549 proliferation and on telomerase activity

OBJECTIVE To investigate inhibitory effect of dicentrine on human lung cancer cell line A549 and its mechanism. METHODS Growth inhibition of dicentrine 0-200 μmol·L^-1 on human lung cancer cell line A549 was examined by MTT colorimetric assay. Inhibitory effect of dicentrine 0-20 mol·L^-1 on telomerase was examined by telomerase repeat amplification protocol(TRAP). Moreover, the anti-tumor mechanism of dicentrine 9 μmol·L^-1 was explored by using UV-vis spectra experiment to examine G-quadruplex stability. RESULTS The inhibitory effect of the dicentrine on A549 cells increased in a concentration (r=0.906) and time-dependent (r=0.949) manner(P<0.05), tumor inhibitory rates of dicentrine 25, 50, 100, 200 μmol·L^-1 on A549 tumor were 33.4% , 88.2%, 88.6% and 89.4% at 72 h, respectively. Dicentrine could significantly decreased telomerase activity(P<0.05); from results of G-quadruplex stability experiments, the quadruplex structure showed increasing T_m values with dicentrine, value of T_m from 48℃ up to 54℃. CONCLUSION ]Dicentrine can significantly decrease telomerase activity by stabilizing G-quadruplex structure. Accordingly, it can significantly inhibit the proliferation of A549 cells.