TP53 and Burkitt lymphoma: We first examined the levels of ARF-BP1 protein expressed by BL cell lines mutant for p53, EBV-transformed lymphoblastoid cells (LCL) lines with wild type (wt) p53, centroblastic (CB) and immunoblastic (IB) diffuse large B cell lymphomas (DLBCL), and the epithelial cell line, MCF 10A (Figure 1A).