The tumour suppressor effects and regulation of cancer stem cells by macrophage migration inhibitory factor targeted miR-451 in colon cancer

Background: This study aimed to investigate the impact of miR-451 on the biological behaviours of colon cancer cells along with its targets interactions. Method: The levels of miR-451 were tested in colon cancer cell lines (SW480 and SW48). Multiple functional and immunological assays were performed to analyse miR-451 induced growth changes in-vitro and downstream effects on target proteins. Results: Overexpression of miR-451 in colon cancer cells led to reduced cell proliferation, increased apoptosis and decrease accumulation of the cells at the GO/G1 phase of the cell cycle. In addition, a significant increase in the number of the cells was noted in the G2-M phase of cell cycle. Moreover, miR-451 reduced the expression of Oct-4, Sox-2 and Snail indicating its role in stem cell and epithelial-mesenchymal transition (EMT) regulation. An inverse correlation between miR-451 and macrophage migration inhibitory protein (MIF) protein expression occurred in colon cancer cells. Furthermore, restoration the level of miR-451 in colon cancer cells inhibits tumour spheres formation. Conclusion: miR-451 has tumour suppressor effects in vitro, which can inhibit the cancer-related signalling pathways in colon cancer.