LAG-3 interacts with its ligand major histocompatibility complex II (MHC II) on tumor cells, as well as other emerging and less characterized ligands including fibrinogen-like protein 1 (FGL-1), α-synuclein fibrils (α-syn), galectin-3 (Gal-3) and lymph node sinusoidal endothelial cell C-type lectin (LSECtin), to negatively regulate T-cell function and the immune response.1 The gene discussed is LGALS3; the disease is neoplasm.