miRNAs as important drivers of glioblastomas: a no-brainer?

There is no debate on the relevance of miRNAs in the pathogenesis of cancer. Numerous miRNAs with oncogenic and tumor-suppressive properties have been identified in glioblastoma multiforme (GBM), an aggressive type of brain tumor with dismal prognosis. Differential expression of these biomolecules in several cancer models makes them attractive therapeutic targets for the development of miRNA-based cancer treatments despite the hurdles associated with such an approach. In addition, systemic release of miRNAs also positions them as attractive tools for non-invasive cancer diagnosis and prognosis. This review initially looks at differentially expressed miRNAs in GBMs. Our focus will next be directed towards circulating miRNAs and how these molecules could be leveraged for cancer diagnosis as well as for the assessment of patient response to chemotherapeutic treatments. Finally, we discuss the primary strategies utilized in the development of miRNA-focused therapeutics and summarize preclinical results gathered in GBMs to date.