Interestingly PTPRJ is one of 46 proteins we previously identified using 1,3,4-O-Bu3ManNAz (an azide-modified analog of 1,3,4-O-Bu3ManNAc) in the SW1990 pancreatic cancer line (Tian et al., 2015), indicating that this oncoprotein is responsive to flux through the sialic acid pathway across cancer and ManNAc analog types. Here, PTPRJ is linked to cancer.