title: Using DNA aptamer probe for immunostaining of cancer frozen tissues.
abstract: Tissue immunostaining is critically important in clinical applications, and antibodies have been used extensively as the molecular probes. Recently, aptamer, as a new class of probes, have attracted much attention for their potential clinical and research value. Epithelial cell adhesion molecule (EpCAM) is a specific biomarker which is overexpressed in many cancers of epithelial origin. Here, a DNA-based EpCAM aptamer SYL3C is reported as a probe for the immunostaining of frozen and paraffin-embedded sections of colorectal cancer tissues. Commercialized EpCAM antibodies were also used as a standard control. EpCAM aptamer SYL3C specifically recognized and immunostained cancer nests of colorectal tumor sections, but it neither reacted with background cells within tumor sites nor exhibited cross-reaction to the benign lesions or inflammation of colorectal tissues. No cross-linking to EpCAM-negative malignant tumor sections occurred. Compared with standard antibody staining, our EpCAM aptamer SYL3C protocol is simpler to implement with a shorter reaction time. Moreover, SYL3C can specifically bind with either frozen or paraffin-embedded tissue sections. Since the histopathology of frozen tissue is closer to that of fresh tissue and since frozen sections can be produced more quickly than paraffin-embedded sections, SYL3C immunostaining of frozen sections is a quick protocol that is easy to implement.
authors.affiliation: Xiangya Hospital, Central South University , Changsha, Hunan 410008, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Pu
authors.forename: Zhenxu
authors.initials: Z
authors.lastname: Liu
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.forename: Peng
authors.initials: P
authors.lastname: Yuan
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.forename: Guodong
authors.initials: G
authors.lastname: Wang
authors.forename: Chaoyong James
authors.initials: CJ
authors.lastname: Yang
authors.forename: Huixia
authors.initials: H
authors.lastname: Liu
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000032:analysis*; D052157:Aptamers, Nucleotide; D015815:Cell Adhesion Molecules / Q000032:analysis*; D003106:Colon / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D000071858:Epithelial Cell Adhesion Molecule; D005629:Frozen Sections; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D016612:Paraffin Embedding; D012007:Rectum / Q000473:pathology*
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D052157:Aptamers, Nucleotide; D015815:Cell Adhesion Molecules; D000071858:Epithelial Cell Adhesion Molecule