Gastric cancer cases with SOX2 protein expression (A and C) can present with or without
amplification (B and D, respectively) determined by FISH. Green labeled probes target SOX2, whereas red labeled probes target the 3p arm. Nuclei are stained with DAPI (blue). (E) Sixty-two gDNA gastric cancer samples were assessed for SOX2 copy number status and compared to normal gastric mucosa (calibrator). (F) SOX2 copy number was significantly associated with protein expression, determined by IHC (p < 0.05).