Exploiting the therapeutic potential of microRNAs in human cancer.

Dysregulation of microRNAs (miRNAs) has been widely shown to be associated with the development and progression of cancer. Recent studies discovered a handful of miRNAs with great potential to act as therapeutic targets in various human cancers. Inhibition or overexpression of these oncomirs may regulate the expressions of their associated genes, which in turn represses the proliferation or metastasis of different cancers. Some miRNAs can reverse the phenotype of epithelial-mesenchymal transition, while others can be utilized to sensitize cells to DNA-damaging drugs. Most of their anticancer abilities have been validated in preclinical animal models. A merit of miRNA-based therapy is that it can target plenty of genes in different signaling pathways, but this also comes with the drawback of many unknown off-target effects. In addition, successful delivery is also a major obstacle to effective miRNA-based therapeutics. Nevertheless, new findings from recent studies and the rapid advances in systemic drug delivery systems provide an optimistic perspective on the evolution of the field.