CD274 and brain neoplasm: The ex vivo biodistribution of 89Zr-DFO-Atezolizumab revealed significantly higher uptake in U87-MGvIII and GL261 brain tumors compared to NTB mice (U87-MGvIII vs NTB brains: 1.4 ± 0.2 %ID/g vs 0.2 ± 0.1 %ID/g, p = 0.0012; GL261 vs NTB brains: 1.0 ± 0.2 %ID/g vs 0.3 ± 0.1 %ID/g, p = 0.0032) or mice-bearing PD-L1 negative tumors (GL261 vs GL261PD-L1KO: 1.0 ± 0.2 %ID/g vs 0.3 ± 0.1 %ID/g,  p = 0.0026) (Figure 2D andSupplementary Figure S3C).