Consistent with this notion, Petre et al. [28] have previously shown that MDM2 mRNA levels are highly expressed in PEL tumor samples as compared to that in other B-cell tumors including Burkitt’s lymphoma and different types of diffuse large B-cell lymphoma, after the examination of transcriptional profiles from over 60 B-cell tumors. The gene discussed is MDM2; the disease is diffuse large B-cell lymphoma.