Similarly, enforced expression of MNK1-AA mutant (MNK1-phosphonull) that cannot be phosphorylated for downstream activity caused significant cell death in GM02184, a non-malignant B-cell line, and to a much higher degree in DLBCL cell lines Pfeiffer (GCB-DLBCL) and HLY-1 (ABC-DLBCL) (Fig. 1i), suggesting that expression of an inactive MNK (MNK1-AA) acts as a dominant negative mutant in both MNK1- or MNK2-expressing cells, reaffirming a common or competitive role for both MNKs. This evidence concerns the gene ATP7A and diffuse large B-cell lymphoma.