PDCD1LG2 and neoplasm: Importantly, the expression of immune checkpoint inhibitor genes (PDCD1 for the PD1 receptor; CD274 for programmed death ligand (PDL)-1; PDCD1LG2 for PD-L2; HAVCR2 for TIM3, LAG3, and CTLA4) was also greater in the S4high group (Figure 6B and Figure S10), suggesting a relationship with a more immunologically activated tumor microenvironment [33].