MicroRNA as a novel drug target for cancer therapy.

INTRODUCTION: MicroRNAs (miRNAs), a class of small, regulatory and non-coding RNA molecules, display aberrant expression patterns and functional abnormalities in all kinds of human diseases including cancers. As important emerging modulators in cellular pathways, miRNAs play a key role in tumorigenesis. Correcting these miRNA deficiencies by either up-regulating or down-regulating miRNA function may provide a therapeutic benefit. AREAS COVERED: We herein provide a brief review of miRNA in the following aspects: their possible role of miRNA as oncogenes or tumor suppressors in the pathogenesis of cancer, the abnormally expressed miRNAs in various types of human common cancers, novel drug targets and therapeutic tools for diagnosis, prognosis and treatments of human cancers was also discussed. Finally, we comment on the difficulties and challenges of miRNAs in clinical practice, and the bright perspective for future application. EXPERT OPINION: Targeting of these ectopically miRNAs could provide an important diagnostic or therapeutic strategy for human cancer in the future.