CD274 and renal cell carcinoma: In particular, RCC PDX models demonstrating high transcript expression of immune checkpoint ligands, e.g., as seen for Ren11175K and PD-L1 or Ren11122E for FLG1 and TNFRSF14, might be considered for future establishment of humanized RCC PDX models and response evaluation to current and/or future ICIs (Figure 3E).