Identification of an aptamer targeting hnRNP A1 by tissue slide‐based SELEX
- 17 February 2009
- journal article
- research article
- Published by Wiley in The Journal of Pathology
- Vol. 218 (3), 327-336
- https://doi.org/10.1002/path.2543
Abstract
We report a new in situ tissue slide‐based SELEX strategy targeting neoplastic tissues from breast cancer patients. The methodology, using the molecular differences between clinical specimens, can evolve aptamers to all fractions of tissue. The aptamers may be used as new molecular probes for pathological diagnosis and tumour imaging, and also to reveal the molecular differences that are responsible for the diseases. The specific aptamers were enriched by unequal length strand PCR employing a structured (−) strand primer. After 12 rounds of selection, using the paraffin tissue sections from infiltrating ductal carcinomas as targets, and using the adjacent normal tissue from the same case as controls, one of the enriched ssDNA aptamers, BC15, was selected from a nucleic acid library and characterized as recognizing breast cancer cells either within the tissue sections or from the culture medium, but only weakly binding to adjacent normal cells or immortalized breast cell line MCF10A. The calculated equilibrium dissociation constants (Kd) of BC15 bound to MCF7 cells was 111.0 ± 36.9 nM. Through streptavidin magnetic beads mediated affinity purification assay followed by mass spectrometry identification and western blot confirmation, the target of BC15 was characterized to be hnRNP A1, which was further verified to be specifically and highly expressed in cancerous tissues of breast by hnRNP A1 antibody immunostaining as well as western blot. BC15 aptamer was also used to probe cancer cells in tissues from other pathological types of breast cancers including lobular carcinoma, ductal carcinoma complicated with lobular carcinoma, comedo carcinoma, and lymph node metastasis of breast ductal carcinoma origin or breast lobular carcinoma origin. Therefore, tissue slide‐based SELEX holds promise in identifying tumour markers and developing specific molecular probes for cancer diagnosis. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.This publication has 22 references indexed in Scilit:
- Molecular Recognition of Small‐Cell Lung Cancer Cells Using AptamersChemMedChem, 2008
- Aptamers Evolved from Cultured Cancer Cells Reveal Molecular Differences of Cancer Cells in Patient SamplesClinical Chemistry, 2007
- Aptamers evolved from live cells as effective molecular probes for cancer studyProceedings of the National Academy of Sciences of the United States of America, 2006
- The roles of heterogeneous nuclear ribonucleoproteins in tumour development and progressionBiochimica et Biophysica Acta (BBA) - Reviews on Cancer, 2006
- hnRNP A1 associates with telomere ends and stimulates telomerase activityRNA, 2006
- Relative amounts of antagonistic splicing factors, hnRNP A1 and ASF/SF2, change during neoplastic lung growth: Implications for pre‐mRNA processingMolecular Carcinogenesis, 2004
- hnRNP A1 Nucleocytoplasmic Shuttling Activity Is Required for Normal Myelopoiesis and BCR/ABL LeukemogenesisMolecular and Cellular Biology, 2002
- Heterogeneous Nuclear Ribonucleoprotein A1 and UP1 Protect Mammalian Telomeric Repeats and Modulate Telomere Replication in VitroOnline Journal of Public Health Informatics, 2000
- In vitro selection of RNA molecules that bind specific ligandsNature, 1990
- Systematic Evolution of Ligands by Exponential Enrichment: RNA Ligands to Bacteriophage T4 DNA PolymeraseScience, 1990