KLF4 and Burkitt lymphoma: Nevertheless, overexpression of KLF4 in both the Raji and Jijoye latently infected, EBV-positive, Burkitt lymphoma cell lines was sufficient to induce the expression of the EBV immediate-early proteins, Z and R, as well as the early lytic protein, BMRF1 (Figs 11B and 11C and S8).