Regulatory mechanisms and clinical perspectives of miR-34a in cancer.

MicroRNAs (miRNAs) are evolutionarily conserved, endogenous, noncoding RNA molecules of about 22-24 nucleotides in length that repress gene expression at the posttranscriptional level. MiR-34a plays an important role in the initiation, progression, and therapy of cancer. In addition, the miR-34a expression has also been identified as a diagnostic and prognostic cancer signature. This article introduces the roles of miR-34a in cancer development, metastasis as well as its mechanism of actions on target genes and the functional outcomes of its actions on radio-sensitivity. The paper ends with a brief perspective to the future of miR-34a.