State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 22 Hankou Road, Nanjing, Jiangsu 210093, China.
Anal Chem. 2015 Apr 7;87(7):3736-45. doi: 10.1021/ac504230j. Epub 2015 Mar 12.
We fabricated a multifunctional theragnostic agent Ag-Sgc8-FAM for apoptosis-based cancer therapy and fluorescence-enhanced cell imaging. For cancer therapy, aptamers Sgc8 and TDO5 acted as recognizing molecules to bind CCRF-CEM and Ramos cells specifically. It was found that aptamer-silver conjugates (Ag-Sgc8, Ag-TDO5) could be internalized into cells by receptor-mediated endocytosis, inducing specific apoptosis of CCRF-CEM and Ramos cells. The apoptosis of cells depended on the concentration of aptamer-silver conjugates, as well as the incubation time between cells and aptamer-silver conjugates. The apoptotic effects on CCRF-CEM and Ramos cells were different. Annexin V/PI staining, AO/PI staining, MTT assays and ROS (reactive oxygen species) detection demonstrated the specific apoptosis of CCRF-CEM and Ramos cells. For fluorescence-enhanced cell imaging, Ag-Sgc8-FAM was prepared. Compared to Sgc8-FAM molecules, Ag-Sgc8-FAM was an excellent imaging agent as numerous Sgc8-FAM molecules were enriched on the surface of AgNPs for multiple binding with CCRF-CEM cells and signal amplification. Moreover, AgNPs could increase the fluorescence intensity of FAM by metal-enhanced fluorescence (MEF) effect. Therefore, aptamer-silver conjugates can be potential theragnostic agents for inducing specific apoptosis of cells and achieving cells imaging in real time.
我们制备了一种多功能治疗与诊断一体化试剂 Ag-Sgc8-FAM，用于基于细胞凋亡的癌症治疗和荧光增强细胞成像。在癌症治疗方面，适体 Sgc8 和 TDO5 作为识别分子，特异性地与 CCRF-CEM 和 Ramos 细胞结合。研究发现，适体-银缀合物（Ag-Sgc8、Ag-TDO5）可以通过受体介导的内吞作用被细胞内化，诱导 CCRF-CEM 和 Ramos 细胞的特异性细胞凋亡。细胞的凋亡取决于适体-银缀合物的浓度以及细胞与适体-银缀合物孵育的时间。对 CCRF-CEM 和 Ramos 细胞的凋亡作用不同。Annexin V/PI 染色、AO/PI 染色、MTT 测定和 ROS（活性氧）检测表明 CCRF-CEM 和 Ramos 细胞的特异性凋亡。对于荧光增强细胞成像，制备了 Ag-Sgc8-FAM。与 Sgc8-FAM 分子相比，Ag-Sgc8-FAM 是一种出色的成像剂，因为大量的 Sgc8-FAM 分子富集在 AgNPs 表面，可与 CCRF-CEM 细胞进行多次结合并实现信号放大。此外，AgNPs 可以通过金属增强荧光（MEF）效应增加 FAM 的荧光强度。因此，适体-银缀合物可作为潜在的治疗与诊断一体化试剂，用于诱导细胞的特异性凋亡，并实现实时细胞成像。
