MicroRNAs Implications in the Onset, Diagnosis, and Prognosis of Osteosarcoma

Osteosarcoma (OS) is a primary bone malignancy, which has a high incidence in children and adolescents. The affected cells and tissues show the properties of drug-resistance and the prognosis remains poor in OS; therefore, there is an essential need for novel therapeutic approaches. MicroRNAs (miRNAs) expression pattern has been established to be involved in the pathogenesis of OS. miRNAs are small non-coding RNA molecules, which negatively regulate gene expression at the post-transcriptional level. There are copious miRNAs that have a critical role in the onset of the disease, modulation of disease progression, and response to treatment. At the moment, the recently launched version 3.0 of Human MicroRNA Disease Database (HMDD v3.0) reports that 194 miRNAs are dysregulated in OS that might be involved in proliferation, migration, invasion, and epithelial-mesenchymal transition of tumor cells. The balance between oncogene and tumor suppressor miRNAs has vital importance in the final fate of the cell behaviors in OS. Additionally, networks of miRNAs may act in concert to induce oncogenic or tumor-suppressing properties during the initiation or the progression of OS. Up or down-regulation of these miRNAs affect the status of the disease during or after therapy. To date, over 40 miRNAs have been identified in OS disease that possess oncogenic or tumor-suppressing properties, and treatment approaches are trying to establish a proper level of such miRNAs in favor of OS therapy. The role of miRNAs involved in the pathogenesis of OS and their therapeutic potential are the reference points in this review article.