title: Highly-sensitive amplification-free analysis of multiple miRNAs by capillary electrophoresis.
abstract: Sets of deregulated microRNAs (miRNAs), termed miRNA signatures, are promising biomarkers for cancer. Validation of miRNA signatures requires a technique that is accurate, sensitive, capable of detecting multiple miRNAs, fast, robust, and not cost-prohibitive. Direct quantitative analysis of multiple miRNAs (DQAMmiR) is a capillary electrophoresis (CE)-based hybridization assay that was suggested as a methodological platform for validation and clinical use of miRNA signatures. While satisfying the other requirements, DQAMmiR is not sufficiently sensitive to detect low-abundance miRNAs. Here, we solve this problem by combining DQAMmiR with the preconcentration technique, isotachophoresis (ITP). The sensitivity improved 100 times (to 1 pM) allowing us to detect low-abundance miRNAs in an RNA extract. Importantly, ITP-DQAMmiR can be performed in a fully automated mode using a commercial CE instrument making it suitable for practical applications.
authors.affiliation: Department of Chemistry and Centre for Research on Biomolecular Interactions, York University , 4700 Keele Street, Toronto, Ontario M3J 1P3, Canada.
authors.forename: David W
authors.initials: DW
authors.lastname: Wegman
authors.forename: Farhad
authors.initials: F
authors.lastname: Ghasemi
authors.forename: Anna
authors.initials: A
authors.lastname: Khorshidi
authors.forename: Burton B
authors.initials: BB
authors.lastname: Yang
authors.forename: Stanley K
authors.initials: SK
authors.lastname: Liu
authors.forename: George M
authors.initials: GM
authors.lastname: Yousef
authors.forename: Sergey N
authors.initials: SN
authors.lastname: Krylov
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D045744:Cell Line, Tumor; D019075:Electrophoresis, Capillary / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D057625:Isotachophoresis / Q000379:methods*; D035683:MicroRNAs / Q000032:analysis*; D009369:Neoplasms / Q000235:genetics; D009693:Nucleic Acid Hybridization
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs