CD274 and neoplasm: While the fraction of PD-L1+ tumor cells (PDL1Tum) and PD-L1+ immune cells (PDL1Imm) measured by mIF with the E1L3N anti-PD-L1 antibody correlated with each other, neither cell population was significantly correlated with expression of the PD-L1 gene (CD274), nor with RPPA results from several anti-PD-L1 antibodies (22C3, SP142, E1L3N, 28.8, atezolizumab [Atezo]) (Figure S1M).