Regulatory miRNAs in Colorectal Carcinogenesis and Metastasis

Abstract

Colorectal cancer is one of the most common malignancies and is the second-leading cause of cancer-related death world-wide, which is linked to genetic mutations, epigenetic alterations, and oncogenic signaling activation. MicroRNAs, one of the categories of epigenetics, have been demonstrated significant roles in carcinogenesis and progression through regulating of oncogenic signaling pathways, stem cells, epithelial-mesenchymal transition, and metastasis. This review summarizes the roles of microRNAs in the regulating of Wnt, Ras, TGF-β, and inflammatory signaling pathways, stemness, and epithelial-mesenchymal transition, for carcinogenesis and metastasis in colorectal cancer. Improving our understanding of the mechanisms of regulatory interactions of microRNAs with signaling pathways in colorectal cancer formation and progression will aid in determining the genes responsible for colorectal cancer initiation, progression, metastasis, and recurrence and, finally, in developing personalized approaches for cancer prevention and therapy.

Keywords: cancer stem cells; colorectal cancer; epithelial-mesenchymal transition (EMT); metastasis; miRNA.

Figure 1

Scheme of the regulatory miRNAs and signaling pathways in colorectal cancer. There is a regulatory network linked to miRNAs and their targets, such as miRNAs regulating Wnt, Ras, transforming growth factor β (TGF-β),inflammatory, cytokine and chenmokines, cancer stem cells, epithelial-mesenchymal (EMT), and metastasis signaling pathways (in different colors). In addition, these signaling pathways are linked and regulated by each other.