Recently, microRNAs (miRNAs) have received increasing attention in the field of cancer research. miRNAs play important roles in many normal biological processes; however, the aberrant miRNA expression and its correlation with the development and progression of cancers is an emerging field. Therefore, miRNAs could be used as biomarkers for diagnosis of cancer and prediction of prognosis. Importantly, some miRNAs could regulate the formation of cancer stem cells and the acquisition of epithelial–mesenchymal...