title: The Yin and Yang of microRNA Assay Methods.
abstract: microRNA assessments in biological samples can be performed by different methods that mainly rely on hybridization process, qPCR or RNA sequencing. With the aim to detect and validate microRNA biomarkers in tumor samples, we challenged the consistency of the quantitative results obtained with the different methods.
  
  
  
  We measured microRNA concentrations in several biological samples such as cultured tumor cells or tumor tissues (frozen tissues or FFPE samples) using different microRNA assay methods, in particular hybridization to AffymetrixTM arrays, qPCR and digital droplet qPCR (BioradTM) based on Taqman microRNA assays (Life TechnologiesTM). We also compared our results to other data that have been obtained with different technical approaches and available in the literature.
  
  
  
  We found poor consistency for the microRNA amounts measured in the samples assayed by the different methods. Both technical platforms and microRNA assays protocols may be responsible for the observed inconsistencies.
  
  
  
  When assaying microRNAs for clinical purpose or fundamental researches it seems necessary to keep in mind the specific pitfalls of all the microRNA detection methods such as those we disclose here. Obviously, valid inter sample comparisons and meaningful multicenter studies can only be obtained when microRNA assessments are strictly performed with identical technical approaches and reagents.
authors.affiliation: Grenoble Institut des Neurosciences, Chemin Fortune Ferrini, F-38000 Grenoble, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Guttin
authors.forename: Helene
authors.initials: H
authors.lastname: Ipas
authors.forename: Maud
authors.initials: M
authors.lastname: Barbado
authors.forename: Catherine
authors.initials: C
authors.lastname: Mouret
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Garcion
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Issartel
mesh_terms: D001483:Base Sequence; D045744:Cell Line, Tumor; D020869:Gene Expression Profiling / Q000379:methods*; D005909:Glioblastoma / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics; D046228:Microarray Analysis / Q000379:methods; D060888:Real-Time Polymerase Chain Reaction; D017423:Sequence Analysis, RNA / Q000379:methods
chemical_list: C524940:MIRN21 microRNA, human; C543800:MIRN210 microRNA, human; D035683:MicroRNAs; C487931:mirnlet7 microRNA, human