title: SELEX aptamer used as a probe to detect circulating tumor cells in peripheral blood of pancreatic cancer patients.
abstract: Many studies have shown that the quantity and dynamics of circulating tumor cells (CTCs) in peripheral blood of patients afflicted with solid tumours have great relevance in therapeutic efficacy and prognosis. Different methods based on various strategies have been developed to isolate and identify CTCs, but their efficacy needs to be improved because of the rarity and complexity of CTCs. This study was designed to examine the possibility of using a SELEX aptamer (BC-15) as a probe to identify rare CTCs out of background nucleated cells. Aptamer BC-15 was selected from a random oligonucleotide library screened against human breast cancer tissue. Fluorescence staining showed that BC-15 had a high affinity for nuclei of human cancer cell lines of various origins as well as CTCs isolated from pancreatic cancer patients, whereas its binding capacity for non-tumor breast epithelial cells and leukocytes was almost undetectable. BC-15+/CD45- cells in cancer patient blood were also found to be cytokeratins 18-positive and aneuploid by immunofluorescence staining and fluorescent in situ hybridization, respectively. Finally, the aptamer method was compared with the well-established anti-cytokeratin method using 15 pancreatic cancer patient blood samples, and enumeration indicated no difference between these two methods. Our study establishes a novel way to identify CTCs by using a synthetic aptamer probe. This new approach is comparable with the anti-cytokeratin-based CTC identification method.
authors: State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors: Jinqiang
authors: J
authors: Zhang
authors: Department of Biochemistry and Molecular Biology, Beijing Institute of Basic Medical Sciences, Beijing, China.
authors: Shaohua
authors: S
authors: Li
authors: State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors: Fang
authors: F
authors: Liu
authors: State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors: Lanping
authors: L
authors: Zhou
authors: Department of Biochemistry and Molecular Biology, Beijing Institute of Basic Medical Sciences, Beijing, China.
authors: Ningsheng
authors: N
authors: Shao
authors: State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors: Xiaohang
authors: X
authors: Zhao
mesh_terms: D000328:Adult; D000368:Aged; D052157:Aptamers, Nucleotide / Q000378:metabolism; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D005260:Female; D006801:Humans; D007633:Keratins / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000473:pathology*; D052156:SELEX Aptamer Technique
chemical_list: D052157:Aptamers, Nucleotide; D007633:Keratins