MCAM and colorectal cancer: The biological roles of Netrin is mediated through two well-recognized receptor families, namely, the deleted receptors in colorectal cancer (DCC) and the uncoordinated 5 (UNC5) receptors [27, 28], but added receptors such as CD146, also termed melanoma cell adhesion molecule and Down syndrome cell adhesion molecule, might also be involved [29, 30].