MicroRNAs and other non-coding RNAs: Implications for cancer patients

The discovery of microRNAs (miRNAs) has shed new light on the role of RNA in gene regulation. MiRNAs are small molecules (size, 19-22 nucleotides) that do not encode proteins but interfere with translation and transcription, thereby regulating gene expression. Multiple miRNAs are dysregulated in human cancer, supporting the hypothesis that miRNAs are involved in the initiation and progression of cancer. Prototypic malignancies in which a role for miRNAs has been demonstrated include chronic lymphocytic leukemia, multiple myeloma, cutaneous T-cell lymphoma and mantle cell lymphoma. More research is necessary, but miRNAs have already improved our understanding of the pathogenesis of cancer. MiRNAs measured in bodily fluids, especially plasma, may be useful as biomarkers for cancer. Beyond miRNAs, several thousand other non-coding (also called ultraconserved) RNAs may be important in the pathogenesis and prognosis of cancer. Some ultraconserved non-coding RNAs interfere with signal transduction by modifying chromatin structures, but most are not yet well characterized. MiRNAs and other non-coding RNAs may be useful for the gene therapy of cancer.