MicroRNA-Mediated Post-Transcriptional Regulation of Epithelial to Mesenchymal Transition in Cancer

Epithelial to mesenchymal transition (EMT) program participates in tissue repair, embryogenesis and numerous pathological conditions, particularly cancer progression and tumor metastasis. A highly complex and strongly controlled post-transcriptionally regulated network of microRNAs (miRNAs) regulates the EMT process. miRNAs are critical parts of the post-transcriptional regulation of gene expression. A set of miRNAs target multiple components of major signaling pathways and downstream effectors of EMT. miRNAs associated with this process are involved in controlling tumor progression and invasiveness either as oncogenes or as tumor suppressors. Since several miRNAs directly affect EMT-related master regulators, they have been discovered to have the potential to be used as biomarkers or targets in EMT-based pathological conditions such as cancer. Therefore, comprehensive understanding of miRNA-EMT correlation with tumor metastatic spread may provide improvements to diagnostic tools or therapeutics for cancer. This review summarizes our current knowledge about some of these important miRNAs and focuses on their specific roles in regulation of the EMT process in cancer.