目的：探讨肝细胞癌（HCC）中miR-376c的表达情况、临床意义及作用机制。方法：用real-time PCR检测miR-376c在HCC组织与癌旁组织、以及不同HCC细胞系与正常肝细胞中的表达，分析miR-376c的表达与HCC患者临床病理特征及预后的关系；将HCC细胞分别转染miR-376c模拟物和阴性对照组序列后，用Transwell法和划痕实验检测细胞的迁移及侵袭，Western blot检测miR-376c可能的靶点高迁移率族蛋白A2（HMGA2）的表达；用免疫组化检测HCC组织中HMGA2的表达，并分析miR-376c与HMGA2之间的相关性。结果： 与癌旁组织或正常肝细胞比较，miR-376c在HCC组织及不同HCC细胞中的表达均明显下调（均P<0.05），miR-376c的低表达与门静脉侵犯（P=0.019）、TNM分期（P=0.012）及Edmondson分级（P=0.009）有关；miR-376c低表达的患者3年生存率明显低于其高表达的患者（P=0.0081）。与转染阴性对照序列的HCC细胞比较，转染miR-376c模拟物的HCC细胞的迁移及侵袭数（56.00 vs. 26.00；45.33 vs. 18.33）明显减少、划痕愈合率明显减低（95.33% vs. 60.00%）、HMGA2的表达明显下调（均P<0.05）；miR-376c高表达的HCC组织中HMGA2表达量明显低于miR-376c低表达的HCC组织（P<0.05），HCC组织中miR-376c与HMGA2的表达呈负相关（r=-0.541，P<0.01）。结论：miR-376c可能是一种抑癌因子，其在HCC中表达降低，从而削弱了对HMGA2的抑制、促进了HCC细胞的迁移与侵袭。
Expression of miR-376c in hepatocellular carcinoma cells and its relation with high mobility group A2
Objective: To investigate the miR-376c expression in hepatocellular carcinoma (HCC) and its clinical significance and action mechanism. Methods: The miR-376c expressions in HCC tissues and tumor adjacent tissues as well as in different HCC cell lines and normal hepatic cells were determined by real-time PCR, and the relations of miR-376c expression with the clinicopathologic features and prognosis of HCC patients were analyzed. After the HCC cells were transfected with miR-376c mimics or negative control sequence, the cell migration and invasion were measured by Transwell assay and wound healing assay respectively, and the protein expression of high mobility group A2 (HMGA2), a potential downstream target of miR-376c, was measured by Western blot analysis. The protein expressions of HMGA2 in HCC tissues were also examined by immunohistochemical staining, and then the correlation between miR-376c and HMGA2 expressions was analyzed. Results: Compared with tumor adjacent tissues or normal hepatic cells, the miR-376c expressions in HCC tissue and different types of HCC cells were significantly down-regulated (all P<0.05); the miR-376c expression was significantly related with the portal vein infiltration (P=0.019), advanced TNM stage (P=0.012) and advanced Edmondson degree (P=0.009); the 3-year survival rate in patients with low miR-376c expression was significantly lower than that in those with high miR-376c expression (P=0.0081). In HCC cells compared with HCC cells transfected with negative control sequence, the numbers of migrating and invading cells (56.00 vs. 26.00; 45.33 vs. 18.33) and wound healing rate (95.3% vs. 60%) were significantly reduced, and the HMGA2 protein expression was significantly down-regulated (all P<0.05); the HMGA2 protein expression in HCC tissues with high miR-376c expression was significantly lower than that in those with low miR-376c expression (P<0.05), and the miR-376c expression was negatively correlated with HMGA2 expression in HCC tissues (r=–0.541, P<0.01). Conclusion: MiR-376c is probably a tumor suppressor, and is down-regulated in HCC, which thereby weakens the inhibition on HMGA2 and promotes the migration and invasion of HCC cells.