The roles of microRNAs in sarcomas.

MicroRNAs are a class of small regulatory RNAs that influence the stabilities and translational efficiencies of target mRNAs. They have been implicated in an increasing number of biological processes, including carcinogenesis. A huge body of literature exists documenting up- or down-regulation of specific microRNAs during carcinogenesis and identifying molecular pathways by which these microRNAs influence every aspect of cancer development, including proliferation, angiogenesis, and metastasis. These studies have provided many insights into basic cancer biology as well as allowing identification of novel biomarkers and potential drug targets. However, the vast bulk of this literature concerns solid epithelial tumours, while sarcomas remain relatively under-studied. The purpose of this article is to review the roles of microRNAs in sarcomas and to highlight microRNAs or related molecular pathways that demonstrate consistent roles within individual or across sarcoma subtypes, with a view to identifying the key regulatory molecules. Further insights into sarcoma biology may be particularly valuable since sarcomas represent a tumour group with a particularly poor prognosis and rather limited treatment options.