Fig. 3

EBV infection and CHAF1A protein expression. A: EBER staining by in situ hybridizations and paired CHAF1A staining by IHC in five EBV-positive GC samples (No.1–5) and in one typical EBV-negative GC sample (No.6), respectively (typical micrograph at 200 × magnification). Because EBER was detected previously, the slice sections or the sampling tissues for CHAF1A detection are not the same as EBER. B: IHC score of CHAF1A between EBV + and EBV- samples. C: The ROC curve for EBV infection prediction by CHAF1A IHC score. D: Positive rate of EBV infection according to CHAF1A expression level. Based on the optimal threshold of CHAF1A IHC score for the maximum ROC curve values, the patients are dichotomized into high and low subgroups. E: EBV infection improves CHAF1A protein expression. F: Quantization results of grayscale values in (E). IHC immunohistochemistry, ROC receiver operating characteristic curve, AUC the areas under the ROC curves