Résumé
MicroRNA(miRNA) is one of the non-coding RNAs with approximate 21 nucleotides in size,which can target messenger RNA (mRNA) to silence gene expression post-transcriptionally.Recent studies have shown that miRNAs play important roles in many physiological and pathological processes,including signal transduction,stem cell differentiation,tumor genesis and development,infection and immunity.Circulating miRNAs are ubiquitous and highly stable,and their profiles are specifically deregulated in different disease processes,thus having the potent to be novel biomarkers for disease diagnosis,prognosis evaluation and treatment assessment.At the same time,it will be the challengc to explore disease-associated miRNA profiles for the development of future molecular diagnostics,as well as to establish standard procedures in detection and effective external quality assessment.