肝癌组织中miR-433表达及其对多西他赛化疗耐药的机制研究

Mechanisms of the docetaxel on the differential expression of miR433 in liver cancer tissue and its effect on the chemoresistance

目的研究肝癌组织中miR-433表达及其对多西他赛(DOC)化疗耐药机制。方法常规培养人肝癌细胞株(HepG2)的DOC耐药的肝癌细胞(HepG2/DOC)。将实验分为3组:正常组、对照组(miR433-NC2)和实验组(miR-433-mimics)。以实时定量聚合酶链反应法测定miR-433基因在肝癌和癌周组织的表达,用Hoechst33342/PI染色法测定细胞凋亡率,用蛋白质印迹法检测cAMP反应元件结合蛋白(CREB1)表达;用荧光素酶报告基因分析miR-433和CREB1的关系。结果 miR-433基因在癌旁组织、肝癌组织中的表达分别为0.98±0.03和0.30±0.14,miR-433与CREB1具有靶向调控关系。正常组、对照组和实验组的细胞的凋亡率分别为(45±8)%,(43±11)%和(78±15)%;这3组的CREB1表达量分别为0.99±0.08,0.95±1.01和4.78±0.57。上述指标:实验组与正常组和对照组相比,差异均有统计学意义(均P<0.05)。结论过表达miR-433能够明显抑制HepG2/DOC增殖,并通过调控CREB1的表达来增强细胞对DOC的敏感性。

Objective To study the expression of miR433 in liver cancer tissue and its effect on the chemoresistance to docetaxel(DOC).Methods DOC-resistant liver cancer cells(HepG2/DOC)were conventionally cultured and divided into three groups:normal group,control group(miR433-NC2)and test group(miR-433-mimics).The expression of miR-433 was detected by real time quantitative-polymerase chain reaction in liver cancer and paracancer tissues.The apoptosis rate and the expression of cAMP response element binding protein(CREB1)were detected by Hoechst33342/PI staining and Western blot,respectively.The relationship between miR-433 and CREB1 was analyzed by prime enzyme reporter gene analysis.Results The expression of miR-433 in adjacent tissues and liver cancer tissues was 0.98±0.03 and 0.30±0.14.miR-433 and CREB1 had a targeted regulation relationship.The apoptosis rates in normal group,control group and test group were(45±8)%,(43±11)%,(78±15)%,respectively;the expression of CREB1 in the three groups were 0.99±0.08,0.95±1.01,4.78±0.57.The differences of the factors were statistically significant between test group and normal group,control group(all P<0.05).Conclusion Overexpression of miR-433 significantly inhibited the proliferation of HepG2/DOC and enhanced the cell sensitivity to DOC by regulating CREB1 expression.