miR-451抑制肝癌HepG2细胞增殖及其在肝癌诊断和预后中的作用

Inhibitory effect of miR-451 on proliferation of hepatic carcinoma HepG2 cells and its prospect in hepatic carcinoma diagnosis and prognosis

目的:寻找用于肝癌诊断的miRNA分子靶标,探讨其在肝癌细胞增殖及细胞周期中的作用及其机制。方法:通过对TCGA数据库中377例肝癌样本和37例癌旁样本的miRNAs表达数据资料进行统计分析,得到一组包含33个差异表达的miRNA。对差异表达的miRNA采用受试者工作特征曲线(ROC曲线)和Kaplan-Meier生存分析进行进一步的筛选,同时结合现有文献最终选择miR-451作为研究目标。向人肝癌细胞株Hep G2转染p LVX-sh RNA2-miR-451,使之过表达miR-451,通过CCK-8细胞增殖实验检测其对Hep G2细胞增殖能力的影响,用流式细胞术观察对Hep G2细胞细胞周期的影响。结果:miR-451在肝癌组织中的表达水平明显低于癌旁组织[(473.40±390.24)vs(1 990.47±2 118.04),P<0.05],且可以作为肝癌诊断的标志物,ROC值为0.91(敏感度0.89,特异性0.87)。体外实验结果表明,过表达miR-451后肝癌Hep G2细胞增殖能力明显降低[48 h:(0.69±0.04)vs(1.08±0.05);72 h:(0.76±0.07)vs(1.52±0.02);均P<0.01],大量细胞被阻滞于S期(P<0.05)。结论:miR-451不但可以作为诊断肝癌和指示预后的生物标志物,还具有抑制肝癌细胞增殖的作用。

Objective： To explore the mRNA molecular targets for diagnosis of hepatic carcionoma and to investigate their functional roles in proliferation and cell cycle of hepatic cancer cells. Methods： Based on the statistical analysis of miRNA expression data from377 hepatic carcionoma samples and 37 adjacent non-cancerous samples in TCGA database, a group of 33 differentially expressed miRNAs were identified. A further screen of these differentially expressed miRNAs was performed using the receiver operating characteristic curve（ROC curve） and Kaplan-Meier survival analysis; and with referring to the current publications, miR-451 was screened as the study subject. Hep G2 cells were transfected with p LVX-sh RNA2-miR-451 to over-express miR-451. The effect of miR-451 over-expression on the proliferation of Hep G2 cell was determined by CCK-8 assay; while the effect on cell cycles was detected by flow cytometry. Results： The expression of miR-451 in the adjacent non-cancerous tissues was significantly lower than that in cancer tissues（[473.40 ± 390.24] vs [1 990.47 ± 2 118.04], P〈0.05）. Mi R-451 could be used as an early diagnostic biomarker of hepatic carcionoma,with a high ROC value of 0.91（sensitivity 0.89, specificity 0.87）. The results of in vitro experiments showed that the proliferation of Hep G2 cells was significantly decreased after miR-451 over-expression（48 h： [0.69±0.04] vs [1.08±0.05]; 72 h： [0.76±0.07] vs [1.52±0.02]; all P〈0.01）, and a large number of cells were blocked in S phase（P〈0.05）. Conclusion： miR-451 has the potential to be used as a biomarker for hepatic carcionoma diagnosis and prognosis; moreover, it also exhibits the inhibitory effect on proliferation of hepatic cancer cells.