Published online Aug 26, 2015. doi: 10.4331/wjbc.v6.i3.162
Peer-review started: April 12, 2014
First decision: May 14, 2014
Revised: May 8, 2015
Accepted: May 27, 2015
Article in press: May 28, 2015
Published online: August 26, 2015
MicroRNAs are small non-coding RNAs that participate in different biological processes, providing subtle combinational regulation of cellular pathways, often by regulating components of signalling pathways. Aberrant expression of miRNAs is an important factor in the development and progression of disease. The canonical myomiRs (miR-1, -133 and -206) are central to the development and health of mammalian skeletal and cardiac muscles, but new findings show they have regulatory roles in the development of other mammalian non-muscle tissues, including nerve, brain structures, adipose and some specialised immunological cells. Moreover, the deregulation of myomiR expression is associated with a variety of different cancers, where typically they have tumor suppressor functions, although examples of an oncogenic role illustrate their diverse function in different cell environments. This review examines the involvement of the related myomiRs at the crossroads between cell development/tissue regeneration/tissue inflammation responses, and cancer development.
Core tip: The roles of the canonical muscle-associated microRNAs are reviewed, including microRNA families miR-1 and miR-133, and single miR-206, which are collectively known as the “myomiRs”. The myomiRs act at the crossroads of the molecular regulation of muscle cells, linking between pathways for cell differentiation, development and maintenance, but also potentiate aberrant cell growth in numerous non-muscle cancers. Typically myomiRs are downregulated in cancers, but some myomiRs are upregulated in a few cancers, yet each dysregulation event advances tumor progression. The review examines normal and disease-linked molecular changes associated with the myomiRs, and collates the extensive literature into accessible tables.