Validation of gene expression profiling by immunohistochemistry. Representative NKTCLs disclosed cytoplasmic staining of neoplastic cells for (A) gzm H, (B) EBI3, (C) VEGFA, nuclear localization of (D) pSTAT3, (E) pAKT, cytoplasmic and nuclear staining of (F) RelA, and positivity for (G) PDGFRα and (H) pPDGFRα. Images were captured with a Zeiss Axioskop2 microscope (Zeiss). Photographs were taken with an Olympus DP70 camera. Image acquisition was performed with Olympus DP Controller 2002, and images were processed with Adobe Photoshop Version 7.0 (Adobe Systems). Original magnification, ×400 (A-H).