siRNA靶向抑制CDCA5基因表达对人肝癌HepG2细胞增殖及凋亡的影响

目的 探讨小干扰RNA（siRNA）靶向抑制细胞分裂周期相关蛋白5（CDCA5）基因表达对人肝癌HepG2细胞株增殖及凋亡的影响。方法 优化siRNA转染条件，将3条靶向抑制CDCA5基因的siRNA载体片段（序列1、2和3）分别高效转染人肝癌HepG2细胞（A、B和C组），并设阴性对照组（NC组）及空白组。免疫印迹法检测转染72h各组CDCA5蛋白的表达水平。CCK-8法检测转染24、48、72、96、120h各组细胞的增殖能力，Annexin V-FITC／PI 双标记流式细胞术检测各组转染48h的凋亡情况。结果 A、B和C组的CDCA5蛋白水平均低于NC组和空白组（P＜0.05），其中B组的表达率最低，抑制率最高，达89.3％，故选择序列2进行后续实验。自转染48h起，B组的相对增殖率均低于NC组和空白组（P＜0.05）；B组转染72h的相对增殖率为（66.58±2.58）％，均低于其他观察时间点（P＜0.05）。B组转染48h的早期和晚期凋亡率分别为（17.43±2.31）％和（22.37±2.21）％，均高于NC组和空白组（P＜0.05）。 结论 通过siRNA能够降低HepG2细胞的CDCA5表达水平，有效抑制HepG2细胞的增殖并促进其凋亡。

Influence of CDCA5-siRNA on proliferation and apoptosis of human hepatocarcinoma cell line HepG2

Objective To investigate influence of CDCA5 small interfering RNA（CDCA5-siRNA） on proliferation and apop- tosis of human hepatocarcinoma cell line HepG2. Methods The HepG2 cells were divided into siRNA groups （A, B and C groups）, universal scrambled negative control siRNA group （NC group） and Blank group. Three CDCA5-siRNAs with different sequences were transfected into HepG2 cells respectively. Western blotting method was used to measure expressions of CDCA5 protein levels at 72h af- ter transfection. The cell proliferation was assessed by CCK-8 at 24, 48, 72, 96 and 120h after transfection. The Annexin V-FITC/PI double-labeled flow cytometry was employed to measure the apoptosis at 48h after transfection. Results The expressions of CDCA5 protein significantly decreased in the CDCA5-siRNA groups （A, B and C groups） compared with NC group and Blank group（ P〈0. 05 ）. Group B had the lowest expression rate and highest inhibition rate（ 89. 3% ）. The relative proliferation rate of group B was significantly lower than those of NC group and Blank group since 48 hours after transfection（P〈O. 05）, and the lowest proliferation rate was （66. 58±2.58）% at 72h in group B. The early and late apoptosis rates were （17.43±2.31） % and （22.37±2.21） % in B group, higher than those of other two groups （ P〈0. 05 ）. Conclusion siRNA down-regulating the expression of CDCA5 gene in human hepatocarcino- ma cell line HeoG2 can inhibit cell nroliferation and increase cell aooDtosis.