EBV-positive ARL cases have a distinct host gene expression signature. (A) HSPA7 is an example of a gene that is more highly expressed in EBV⁺ samples (above) compared with EBV⁻ samples (below). (B) Genes consistently up- and downregulated in the presence of EBV are shown in DLBCL cases. Axes show log₂(x + 1), where x is the gene expression level in units of RPKM as quantified by cufflinks. (C) EBV-associated host gene expression changes are significantly similar in AIDS-related BL and DLBCL. Significantly differentially expressed upregulated (upper) and downregulated (lower) genes in EBV-positive samples are part of the EBV signature in both BL and DLBCL (hypergeometric test). (D) EBV-associated host gene expression changes cluster into pathways, including plasma cell differentiation, maintenance of hematopoietic stem cells, and genes dysregulated in primary effusion lymphoma. Heatmap shows pathways (y-axis) enriched for host expression signatures associated with EBV in a variety of cellular and host settings (x-axis), including HIV-negative sBL, AR BL, AR DLBCL, and LCLs derived from whole peripheral blood infected with high titers of EBV. Enrichment significance is determined by 1-sided Kolmogorov-Smirnov tests.