SELPLG and cancer: Heparin binds to P-selectin glycoprotein ligand-1 (PSGL-1) and blocks platelets to bind to cancer cells via mucin ligands on the cell surface of cancer cells, thus blocking their subsequent interaction with endothelium and reducing metastasis and tumor colonization (Mousa and Mohamed, 2004; Wahrenbrock et al., 2003; Borsig et al., 2001).