基于cell-SELEX技术筛选高转移胃癌细胞系HGC-27核酸适配体

Cell-SELEX-based selection of aptamers for targeting high metastatic gastric canceetastatic gastric cancer cells (HGC-27)

目的筛选针对高转移胃癌细胞(HGC-27)的核酸适配体。方法以HGC-27为靶细胞,以AGS为反筛细胞,利用Cell-SELEX技术逐轮次筛选,从文库中挑选能与HGC-27结合的核酸适配体LW-25。用流式细胞术检测核酸适配体测富集程度,核酸适配体与HGC-27的亲和力及特异性。结果流式细胞仪显示随着筛选轮数的增加,次级文库与靶细胞结合的荧光强度增强。从次级文库中成功挑选出一条能与HGC-27结合的核酸适配体LW-25。并且LW-25能特异性识别HGC-27。胰蛋白酶处理HGC-27后,LW-25与HGC-27的结合能力较处理前明显下降。结论核酸适配体LW-25能特异性识别HGC-27,是潜在具有诊断胃癌转移的分子探针。

Objective To screen aptamers binding highly metastatic gastric cancer cells(HGC-27). Methods HGC-27 cells were selected as targeted cells and AGS cells were selected as negative cells.A DNA aptamer named LW-25 was successfully selected against HGC-27 cells by using the cell-based systematic evolution of ligands by exponential enrichment (SELEX) method.Flow cytometry was used to monitor the enrichment of the selected DNA pool,and to evaluate the selectivity and the binding affinities of LW-25. Results The subpools binding against HGC-27 cells increased along with selection rounds.We successfully selected a aptamer named LW-25 which could specifically bind against HGC-27 cells.Furthermore,trypsin treatment greatly reduced the binding of LW-25 to HGC-27 cells. Conclusion These studies demonstrated that this HGC-27 specific aptamer LW-25 may be a potential molecular probe to recognize metastatic gastric cancer cells.