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Identification of DNA aptamers toward epithelial cell adhesion molecule via cell-SELEX.

ABSTRACT: The epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is specifically detected in most adenocarcinomas and cancer stem cells. In this study, we performed a Cell systematic evolution of ligands by exponential enrichment (SELEX) experiment to isolate the aptamers against EpCAM. After seven round of Cell SELEX, we identified several aptamer candidates. Among the selected aptamers, EP166 specifically binds to cells expressing EpCAM with an equilibrium dissociation constant (Kd) in a micromolar range. On the other hand, it did not bind to negative control cells. Moreover, EP166 binds to J1ES cells, a mouse embryonic stem cell line. Therefore, the isolated aptamers against EpCAM could be used as a stem cell marker or in other applications in both stem cell and cancer studies.

SUBMITTER: Kim JW

PROVIDER: S-EPMC4213765 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Identification of DNA aptamers toward epithelial cell adhesion molecule via cell-SELEX.

Kim Ji Won JW Kim Eun Young EY Kim Sun Young SY Byun Sang Kyung SK Lee Dasom D Oh Kyoung-Jin KJ Kim Won Kon WK Han Baek Soo BS Chi Seung-Wook SW Lee Sang Chul SC Bae Kwang-Hee KH

Molecules and cells 20140929 10

The epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is specifically detected in most adenocarcinomas and cancer stem cells. In this study, we performed a Cell systematic evolution of ligands by exponential enrichment (SELEX) experiment to isolate the aptamers against EpCAM. After seven round of Cell SELEX, we identified several aptamer candidates. Among the selected aptamers, EP166 specifically binds to cells expressing EpCAM with an equilibriu ...[more]

PMID: 25266702

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