MicroRNAs (miRNAs) are small non-coding RNAs found in eukaryotic organisms that regulate gene expression. Dismissed as “junk” until about a decade ago, it is now widely accepted that they play an important functional role in a wide array of cellular processes.
MiRNAs regulate gene expression by targeting individual or multiple messenger RNAs (mRNAs). Perfect or partial base pairing with the target mRNA promotes cleavage of the RNA in plants and inhibition of protein translation in animals. Many studies have demonstrated that dysregulation of these miRNAs is associated with various diseases suggesting there is potential for use of miRNAs in diagnosis and treatment.
Much of the study of miRNA and disease has focused on cancer and neurological disorders. Not surprising since cancer is the leading cause of death worldwide in 2010 and it is estimated that neurological disorders may affect as many as a billion people. There are urgent needs for early diagnosis and treatment in both areas.
Several miRNAs have been linked with various types of cancer due to their regulatory role in cellular development, including: differentiation, proliferation, and apoptosis. Neural miRNAs are known to be involved at various stages of synaptic development, including: dendritogenesis, synapse formation and synapse maturation. Since miRNAs exhibit specific expression profiles in tissues and tumor cells it makes sense that they could serve as biomarkers for these and other diseases. (read more… )