For instance, netrin-1, a classic bifunctional guidance cue, is capable of attracting or repelling axon projection by differentially interacting with its receptors, deleted in colorectal cancer (DCC) [27, 28], neogenin [28, 29], uncoordinated-5 (UNC5) [30, 31], and Down syndrome cell adhesion molecule (DSCAM) [32, 33]. The gene discussed is DSCAM; the disease is cancer.