MicroRNA-129-5p在卵巢癌中表达的光声成像研究

Photoacoustic imaging of MicroRNA-129-5p expression inovarian cancer

目的探究基于酪氨酸酶报告基因CMV/TYR-3xTS的光声成像监测卵巢癌中miR-129-5p的表达。方法采用分光光度计测量黑色素含量和酪氨酸酶活性;采用光声成像检测细胞和小鼠中的光声信号;采用实时定量PCR检测细胞和小鼠皮下组织中的miR-129-5p的表达。结果细胞中黑色素含量和酪氨酸酶活性随着CMV/TYR-3xTS质粒浓度的升高(0、1、2、4μg)而呈剂量依赖性升高,并随着外源导入的miR-129-5p浓度升高(0、5、10、20、40nmol/L)而逐渐降低。在卵巢癌细胞SKOV3中用不同浓度的甲基化药物5-Aza-dC(0、0.5、1.0、2.0μmol/L)处理后,miR-129-5p的表达被激活,黑色素含量、酪氨酸酶活性和光声信号呈剂量依赖性逐渐降低。在动物水平上,用5-Aza-dC处理后,小鼠移植CMV/TYR-3xTS处的光声信号显著减少,而作为内参的生物发光信号没有明显的变化。结论酪氨酸酶报告基因CMV/TYR-3xTS可作为新的miRNA成像探针在细胞和动物水平监测miRNA的动态表达。

Objective To investigate the expression of miR-129-5 p in ovarian cancer by photoacoustic imaging using tyrosinase reporter CMV/TYR-3 xTS.Methods The melanin content and tyrosinase activity were measured using a spectrophotometer.Photoacoustic imaging was used to detect the photoacoustic signals in cells and mice.Real-time quantitative PCR was used to detect the expression of miR-129-5 p in cells and subcutaneous tissues of mice.Results The melanin content and tyrosinase activity in the cells increased in a dose-dependent manner with the increase of CMV/TYR-3 xTS plasmid concentration(0,1,2,4μg),and gradually decreased with the increase of exogenously introduced miR-129-5 p concentration(0,5,10,20,40 nmol/L).After treatment with the methylated drug 5-Aza-dC(0,0.5,1,2μmol/L)in ovarian cancer cell SKOV3,the expression of miR-129-5 p was activated,and the melanin content,tyrosinase activity and photoacoustic signal gradually decreased in a dose-dependent manner.At the animal level,after treatment with 5-Aza-dC,the photoacoustic signal at the CMV/TYR-3 xTS was significantly reduced,whereas the bioluminescence signal as an internal reference did not change significantly.Conclusion The tyrosinase reporter gene CMV/TYR-3 xTS can be used as a novel miRNA imaging probe to monitor the dynamic expression of miRNA at the cellular and animal levels.