靶向下调Cep55表达水平对肝癌细胞增殖能力的影响
Effect of knockdown of centrosomal protein 55ku on the proliferation of human hepatocellular carcinoma cells

摘要：目的 通过siRNA干扰技术下调中心体相关蛋白Cep55的表达水平，并检测对肝癌HepG2和Hep3B细胞增殖能力的影响，为原发性肝癌的基因靶向治疗提供理论依据。方法 应用Cep55特异性siRNA转染肝癌HepG2和Hep3B细胞，采用Real-time PCR和Western blot方法分别从mRNA和蛋白质水平检测Cep55 siRNA对Cep55基因的干扰效果，MTT法检测下调Cep55表达水平时细胞增殖能力的变化，流式细胞仪检测细胞周期分布变化。结果 与阴性对照组比较，干扰siRNA组Cep55的mRNA及蛋白表达水平均出现明显降低(P<0.05)；MTT检测结果显示下调Cep55表达水平能够显著抑制肝癌细胞增殖(P<0.05)；流式细胞仪检测显示下调Cep55表达水平能够增加G1期细胞的比例，同时降低G2-M期细胞的比例，出现明显的G2期阻滞。结论 下调Cep55表达水平能够显著抑制肝癌细胞的增殖能力，并出现G2期阻滞，提示Cep55可能成为原发性肝癌的有效治疗靶点。
ABSTRACT: Objective To investigate the effects of small interfering RNA (siRNA) knockdown of centrosomal protein 55ku (Cep55) on the proliferation capacity of human hepatocellular carcinoma cells HepG2 and Hep3B in vitro so as to provide theoretical evidence for gene-targeted therapy for human hepatocellular carcinoma. Methods Cep55 siRNA was transfected into human hepatocellular carcinoma cells HepG2 and Hep3B with Lipofectamine 2000. Real-time PCR and Western blotting were used to detect the expression of Cep55 at mRNA and protein levels. Cell proliferation was evaluated by MTT assay and cell cycle analysis was performed by flow cytometry. Results Cep55 siRNA was successfully transfected into HepG2 and Hep3B cells, resulting in the significant inhibition of Cep55 mRNA and protein expressions (P<0.05). Downregulation of Cep55 significantly decreased the proliferation of HepG2 and Hep3B cells (P<0.05) and induced G2 cell cycle arrest. Conclusion Downregulating the expression of Cep 55 can inhibit the proliferation of hepatocellular carcinoma cells and induce G2 cell cycle arrest, which indicates that Cep 55 may be a potential target for primary hepatocellular carcinoma therapy