Evaluating The Clinical Application Potential Of Tumor Related Aptamers And Screening A Novel SsDNA Aptamer Against Extracellular Domain Of Mucin 16 Using CE-SELEX

Objective:Nucleic acid aptamers are single-stranded(ss)oligonucleotides with unique intramolecular conformations and specific recognition abilities to targets.Currently,there has been a great deal of studies about preparation of aptamers towards tumor specific proteins,such as CEA,EpCAM,Mucinl.The purpose of this study is to further verify the tumor targeting abilities and to evaluate the clinical application potential of these aptamers.CA125 has been proven closely related to peritoneal metastasis of gastric cancer.This study was aimed to screening and identifying a novel ssDNAAptamer against extracellular domain of Mucin 16.Methods:Using confocal laser imaging method for evaluation of ability of CEA、Mucin1、Epcam aptamers target to cancer tissues.Using CE-SELEX to screen the aptamers of Mucin 16 ectodomain-synthetic peptide,while quantitative determination Kd values of each round and obtained aptamers.Also,using confocal laser imaging method for evaluation of ability of aptamers target to cancer cells.Results:The aptamers of CEA EpCAM,Mucin 1 performed abilities of alone or simultaneously targeting to the cancer tissues,but not with to adjacent tissues.After five cycles screening,cloning and sequencing,affinity and cell binding ability measuring,we successfully confirmed an aptamer,specifically targeting the peptide of Mucin16 extracellular domain.Conclusion:The aptamers of CEA,Mucinl,EpCAM have potential on clinical applications.The aptamer we confirmed could be used as a new agent in diagnosis and treatment on peritoneal metastasis of gastric cancer.