title: Cell-SELEX based selection and optimization of DNA aptamers for specific recognition of human cholangiocarcinoma QBC-939 cells.
abstract: Cholangiocarcinoma (CCA) is a very aggressive biliary tract malignancy with no efficient early diagnosis and therapeutics available, so there is a call for effective molecular probes. Herein, we performed cell-based systematic evolution of ligands by exponential enrichment (cell-SELEX) to obtain aptamers for the specific recognition of human cholangiocarcinoma QBC-939 cells. By coordinating sequence homology analysis and secondary structure analysis, we successfully obtained two aptamers with dissociation constants (Kd) in the low nanomolar range. A 23 nt truncated sequence was identified after further analysis on the secondary structure. More importantly, because hepatocellular carcinoma SMMC-7721 cells were employed as the control in the counter selection, the obtained aptamers demonstrated excellent specificity to the target cells, and no binding to several other hepatocellular carcinoma cell lines was observed. Moreover, the aptamers were initially found to recognize membrane proteins, giving them great potential in the field of biomarker discovery. These newly generated aptamers may play a key role in the early diagnosis and clinical treatment of CCA.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of biology, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. kmwang@hnu.edu.cn guoqping@126.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Wan
authors.forename: Ling
authors.initials: L
authors.lastname: Ye
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Yang
authors.forename: Qiuping
authors.initials: Q
authors.lastname: Guo
authors.forename: Kemin
authors.initials: K
authors.lastname: Wang
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Huang
authors.forename: Yuyu
authors.initials: Y
authors.lastname: Tan
authors.forename: Baoyin
authors.initials: B
authors.lastname: Yuan
authors.forename: Qin
authors.initials: Q
authors.lastname: Xie
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D001483:Base Sequence; D001650:Bile Duct Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D018281:Cholangiocarcinoma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D005434:Flow Cytometry; D015723:Gene Library; D006801:Humans; D018613:Microscopy, Confocal; D015335:Molecular Probes / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D052156:SELEX Aptamer Technique
chemical_list: D052157:Aptamers, Nucleotide; D015335:Molecular Probes