Circulating microRNAs as Promising Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is one of the most common cancers and a leading cause of cancer-related deaths worldwide. Despite numerous advances in therapeutic approaches, this cancer has a poor prognosis when it is diagnosed at late stages. Therefore, the scientific effort is nowadays directed towards the development of new non-invasive and dynamic biomarkers to improve the survival expectancy of CRC patients. In this sense, deregulated expression of many miRNAs has been shown to play an important role for CRC carcinogenesis and dissemination. Noticeably, an increasing number of studies highlight that circulating miRNAs, including those traveling inside exosomes or those released by tumor cells into circulation, constitute a promising tool for early detection, prognosis and therapy selection of CRC. Therefore, in this review we focus on the clinical potential of blood circulating miRNAs as emerging biomarkers with high value to improve the clinical management of CRC patients, providing a deep and complete perspective of the realities and challenges to translate these biomarkers to the clinical context.