microRNA profiling of EBV-positive vs. EBV-negative BL cases. (a) Heatmap of miRNA differential expression in EBV-positive BL versus EBV-negative BL cases. 12 EBV-negative and 6 EBV-positive BL cases were compared in terms of viral and human miRNA expression using the Agilent® microRNA expression microarray technology. While each column represents a BL case, rows represent human miRNAs differentially expressed in two groups or viral miRNAs expressed in EBV-positive cases. We recognized 8 out of 470 cellular miRNA deregulated in EBV-positive and -negative BLs (FDR < 0.05). Indeed 13 out of 46 EBV miRNAs were found to be expressed in EBV-positive BL cases. (b) Validation by RT-qPCR of the array results on the cellular miRNAs differentially expressed between EBV-positive and EBV-negative BL cases. The graph is representative of three different qRT-PCR experiments. Error bars represent standard deviation between duplicates.