PD-1, a type I transmembrane glycoprotein bound by glycoproteins PD-L1 (B7-H1, CD274) and PD-L2 (B7-DC, CD273) [15, 16] can promote tumor growth by preventing activation of cytotoxic T-cells [13, 14]. The gene discussed is PDCD1LG2; the disease is neoplasm.