KLF4 and Burkitt lymphoma: Nevertheless, CHOP expression (at a similar level to that expressed in EBV-infected NOKs) did not induce lytic EBV reactivation in the EBV-positive Burkitt lymphoma lines, Mutu I (Fig 10E) and Raji (S8 Fig), and as expected did not activate expression of epithelial cell differentiation proteins such as BLIMP1 and KLF4 in B cells (Figs 10F and S8).