CD274 and neoplasm: Compared to monotherapy anti-PDL1 or isotype IgG, the addition of 16 Gy IR resulted in observable tumor regression and a growth delay (anti-PDL1 p = 0.003, IgG p = 0.001; median time to endpoint anti-PDL1 8.5 days, 16 Gy + anti-PDL1 35 days, IgG 9 days, 16 Gy + IgG 40 days) (Figure 4b).