Fig. 2

Expressions of several critical molecules in GC PDX models. a EGFR expression was evaluated with scores of: 0, 1+, 2+, and 3+. For the FISH assay, the red and green signals represented EGFR and CEN7, respectively. Scale bar represents 100 μm. b HER3 expression was evaluated with scores of: 0, 1+, 2+, and 3+. Scale bar represents 100 μm. c MET expression was evaluated with H-scores. Scale bar represents 100 μm. d EBV infection status was detected by EBV-encoded RNA in situ hybridization. EBER-positive cells were observed in 20% or more of the tumor cells. Scale bar represents 100 μm. e PD-L1 expression was detected in the placenta (positive control), normal gastric tissue (negative control), and PDX models. Patterns with ≥ 5% positive tumor cells or immune cells was considered to be PDL-1 positive. Scale bar represents 100 μm