下调UHRF1的表达在抑制肝癌进展中的作用

目的 探讨UHRF1的异常表达在肝癌（hepatocellular carcinoma, HCC）进展中的作用机制。方法 采用RT-PCR和Western blot法检测UHRF1在20例HCC标本中的mRNA和蛋白表达水平， Western blot法检测不同转移潜能的肝癌细胞HepG2、SMMC7721、MHCC97L和HCCLM3中的UHRF1 的表达水平；siRNA技术干扰HCCLM3细胞中UHRF1表达后，MTT法检测细胞增殖，Western blot 法检测BAX和BCL-2表达水平的改变，流式细胞术检测HCCLM3细胞周期和细胞凋亡的变化。结 果 UHRF1在肺癌组织中的表达水平较癌旁组织显著上调（P<0.05），随着肝癌细胞转移潜能升高而UHRF1表达水平也依次升高（P<0.01）；siRNA技术干扰HCCLM3细胞中UHRF1表达后，HCCLM3细胞生长速度明显下降（P＜0.05），HCCLM3细胞的促凋亡蛋白BAX表达水平明显上升，而抑凋亡蛋白BCL-2表达水平明显下降；UHRF1-siRNA干扰HCCLM3细胞48 h时，细胞周期分布无明显影响（P＞0.05）；但UHRF1表达下调有促凋亡作用，与对照组相比，干扰组的细胞凋亡率显著升高，差异有统计学意义（P＜0.05）。结论 UHRF1基因在肝癌组织中表达上调，下调UHRF1的表达能够抑制肝癌进展，可能是通过诱导肿瘤细胞凋亡来实现的。

Down-regulating UHRF1 Expression could Inhibit Progression of Hepatocellular Carcinoma

Objective To explore the role and mechanism of UHRF1 abnormal expression in the invasion and metastasis of hepatocellular carcinoma(HCC). Methods The mRNA and protein levels of UHRF1 in 20 cases of HCC tissues were detected by real-time RT-PCR and Western blot. Western blot assay was cond ucted to detect UHRF1 expression in HepG2 and SMMC7721 with low metastasis potency, as well as in MHCC97L and HCCLM3 with high metastasis potency. After siRNA was successfully performed in HCCLM3 cells to down-expression, cell proliferation was assayed by MTT method. Expression of Bax and Bcl-2 were detected by Western blot. Cell cycle and apoptosis of HCCLM3 cells were assayed by FCM. Results UHRF1 expression was overexpressed in human HCC tissues compared with the matched adjacent non-tumorous hepatic tissues(P<0.05). UHRF1 expression in MHCC97L and HCCLM3 groups with high metastasis potency were higher than those in HepG2 and SMMC7721 groups with lowmetastasis potency(P<0.01). After siRNA was successfully performed in HCCLM3 cells to down-ulate UHRF1 expression, the growth speed of HCCLM3 cells in HCCLM3-UHRF1- siRNA groups was faster than those in HCCLM3 and HCCLM3-Neg-siRNA groups(P<0.05). UHRF1 depletion triggered apoptotic pathways by promoting the expression of BAX and by suppressing BCL-2 expression in HCCLM3 cells. Conclusion UHRF1 gene expression was significantly upregulated in HCC tissues. Down-regulating UHRF1 expression could suppress the growth of HCC cells through inducing cell apoptosis.