Min Xuehong, Xia Lei, Zhuang Yuan, Wang Xudong, Du Jie, Zhang Xiaojin, Lou Xiaoding, Xia Fan
Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
College of Materials and Chemistry Engineering, Hainan University, Haikou 570228, China.
Sci Bull (Beijing). 2017 Jul 30;62(14):997-1003. doi: 10.1016/j.scib.2017.06.008. Epub 2017 Jun 23.
Monitoring telomerase activity with high sensitive and reliable is of great importance to cancer analysis. In this paper, we report a sensitive and facile method to detect telomerase activity using AIEgens modified probe (TPE-Py-DNA) as a fluorescence reporter and exonuclease III (Exo III) as a signal amplifier. With the aid of telomerase, repeat units (TTAGGG)n are extended from the end of template substrate oligonucleotides (TS primer) that form duplex DNAs with TPE-Py-DNA. Then, Exo III catalyzes the digestion of duplex DNAs, liberating elongation product and releasing hydrophobic TPE-Py. The released hydrophobic TPE-Py aggregate together and produce a telomerase-activity-related fluorescence signal. The liberated product hybridizes with another TPE-Py-DNA probe, starting the second cycle. Finally, we obtain the target-to-signal amplification ratio of 1:N. This strategy exhibits good performance for detecting clinical urine samples (distinguishing 15 cancer patients' samples from 8 healthy ones) and checking intracellular telomerase activity (differentiating cell lines including HeLa, MDA-MB-231, MCF-7, A375, HLF and MRC-5 from the cells pretreated with telomerase-related drug), which shows its potential in clinical diagnosis as well as therapeutic monitoring of cancer.
高灵敏度和高可靠性地监测端粒酶活性对癌症分析至关重要。在本文中，我们报道了一种灵敏且简便的方法来检测端粒酶活性，该方法使用聚集诱导发光（AIE）分子修饰的探针（TPE-Py-DNA）作为荧光报告分子，并以外切核酸酶III（Exo III）作为信号放大器。在端粒酶的作用下，重复单元（TTAGGG）n从模板底物寡核苷酸（TS引物）的末端延伸，TS引物与TPE-Py-DNA形成双链DNA。然后，Exo III催化双链DNA的消化，释放延伸产物并释放疏水性的TPE-Py。释放出的疏水性TPE-Py聚集在一起并产生与端粒酶活性相关的荧光信号。释放的产物与另一个TPE-Py-DNA探针杂交，开始第二个循环。最后，我们获得了1:N的靶标与信号放大比。该策略在检测临床尿液样本（区分15例癌症患者样本和8例健康样本）以及检测细胞内端粒酶活性（区分包括HeLa、MDA-MB-231、MCF-7、A375、HLF和MRC-5等细胞系与经端粒酶相关药物预处理的细胞）方面表现出良好的性能，这表明其在癌症临床诊断以及治疗监测方面具有潜力。
