KRAS and colonic neoplasm: Nussinov and colleagues proposed that the N-RAS-like state of K-RAS4A (i.e., palmitoylated and farnesylated) could influence its high expression in melanoma, and that the K-RAS4B-like state of K-RAS4A (i.e., farnesylated) could contribute to the high expression levels seen in colon cancer (Nussinov et al., 2016).